<?xml version="1.0" encoding="US-ASCII"?>
<!--XBRL Document Created with Wdesk from Workiva-->
<!-- -->
<link:linkbase xsi:schemaLocation="http://www.xbrl.org/2003/linkbase http://www.xbrl.org/2003/xbrl-linkbase-2003-12-31.xsd" xmlns:link="http://www.xbrl.org/2003/linkbase" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
  <link:roleRef roleURI="http://www.xbrl.org/2009/role/negatedPeriodStartLabel" xlink:href="http://www.xbrl.org/lrr/role/negated-2009-12-16.xsd#negatedPeriodStartLabel" xlink:type="simple" />
  <link:roleRef roleURI="http://www.xbrl.org/2009/role/netLabel" xlink:href="http://www.xbrl.org/lrr/role/net-2009-12-16.xsd#netLabel" xlink:type="simple" />
  <link:roleRef roleURI="http://www.xbrl.org/2009/role/negatedNetLabel" xlink:href="http://www.xbrl.org/lrr/role/negated-2009-12-16.xsd#negatedNetLabel" xlink:type="simple" />
  <link:roleRef roleURI="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:href="http://www.xbrl.org/lrr/role/negated-2009-12-16.xsd#negatedTerseLabel" xlink:type="simple" />
  <link:roleRef roleURI="http://www.xbrl.org/2009/role/negatedPeriodEndLabel" xlink:href="http://www.xbrl.org/lrr/role/negated-2009-12-16.xsd#negatedPeriodEndLabel" xlink:type="simple" />
  <link:roleRef roleURI="http://www.xbrl.org/2009/role/negatedLabel" xlink:href="http://www.xbrl.org/lrr/role/negated-2009-12-16.xsd#negatedLabel" xlink:type="simple" />
  <link:roleRef roleURI="http://www.xbrl.org/2009/role/negatedTotalLabel" xlink:href="http://www.xbrl.org/lrr/role/negated-2009-12-16.xsd#negatedTotalLabel" xlink:type="simple" />
  <link:labelLink xlink:role="http://www.xbrl.org/2003/role/link" xlink:type="extended">
    <link:label id="lab_us-gaap_CompensationAndRetirementDisclosureAbstract_E9A882BB97393A27E8B607D5A20A0AC8_label_en-US" xlink:label="lab_us-gaap_CompensationAndRetirementDisclosureAbstract_E9A882BB97393A27E8B607D5A20A0AC8" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Retirement Benefits [Abstract]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_CompensationAndRetirementDisclosureAbstract" xlink:label="loc_us-gaap_CompensationAndRetirementDisclosureAbstract_E9A882BB97393A27E8B607D5A20A0AC8" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CompensationAndRetirementDisclosureAbstract_E9A882BB97393A27E8B607D5A20A0AC8" xlink:to="lab_us-gaap_CompensationAndRetirementDisclosureAbstract_E9A882BB97393A27E8B607D5A20A0AC8" xlink:type="arc" />
    <link:label id="lab_us-gaap_ScheduleOfDefinedBenefitPlansDisclosuresTable_6E0928008DC29508A41207D5A20B1F5F_terseLabel_en-US" xlink:label="lab_us-gaap_ScheduleOfDefinedBenefitPlansDisclosuresTable_6E0928008DC29508A41207D5A20B1F5F" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Schedule of Defined Benefit Plans Disclosures [Table]</link:label>
    <link:label id="lab_us-gaap_ScheduleOfDefinedBenefitPlansDisclosuresTable_6E0928008DC29508A41207D5A20B1F5F_label_en-US" xlink:label="lab_us-gaap_ScheduleOfDefinedBenefitPlansDisclosuresTable_6E0928008DC29508A41207D5A20B1F5F" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Schedule of Defined Benefit Plans Disclosures [Table]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ScheduleOfDefinedBenefitPlansDisclosuresTable" xlink:label="loc_us-gaap_ScheduleOfDefinedBenefitPlansDisclosuresTable_6E0928008DC29508A41207D5A20B1F5F" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfDefinedBenefitPlansDisclosuresTable_6E0928008DC29508A41207D5A20B1F5F" xlink:to="lab_us-gaap_ScheduleOfDefinedBenefitPlansDisclosuresTable_6E0928008DC29508A41207D5A20B1F5F" xlink:type="arc" />
    <link:label id="lab_srt_CounterpartyNameAxis_DEF48C46E23519EAEDF307E4D1EB0A42_terseLabel_en-US" xlink:label="lab_srt_CounterpartyNameAxis_DEF48C46E23519EAEDF307E4D1EB0A42" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Counterparty Name [Axis]</link:label>
    <link:label id="lab_srt_CounterpartyNameAxis_DEF48C46E23519EAEDF307E4D1EB0A42_label_en-US" xlink:label="lab_srt_CounterpartyNameAxis_DEF48C46E23519EAEDF307E4D1EB0A42" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Counterparty Name [Axis]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_CounterpartyNameAxis" xlink:label="loc_srt_CounterpartyNameAxis_DEF48C46E23519EAEDF307E4D1EB0A42" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_srt_CounterpartyNameAxis_DEF48C46E23519EAEDF307E4D1EB0A42" xlink:to="lab_srt_CounterpartyNameAxis_DEF48C46E23519EAEDF307E4D1EB0A42" xlink:type="arc" />
    <link:label id="lab_srt_RepurchaseAgreementCounterpartyNameDomain_12E5D20311180DCCD9FD07E4D1F2BED0_terseLabel_en-US" xlink:label="lab_srt_RepurchaseAgreementCounterpartyNameDomain_12E5D20311180DCCD9FD07E4D1F2BED0" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Counterparty Name [Domain]</link:label>
    <link:label id="lab_srt_RepurchaseAgreementCounterpartyNameDomain_12E5D20311180DCCD9FD07E4D1F2BED0_label_en-US" xlink:label="lab_srt_RepurchaseAgreementCounterpartyNameDomain_12E5D20311180DCCD9FD07E4D1F2BED0" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Counterparty Name [Domain]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_RepurchaseAgreementCounterpartyNameDomain" xlink:label="loc_srt_RepurchaseAgreementCounterpartyNameDomain_12E5D20311180DCCD9FD07E4D1F2BED0" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_srt_RepurchaseAgreementCounterpartyNameDomain_12E5D20311180DCCD9FD07E4D1F2BED0" xlink:to="lab_srt_RepurchaseAgreementCounterpartyNameDomain_12E5D20311180DCCD9FD07E4D1F2BED0" xlink:type="arc" />
    <link:label id="lab_arnc_PensionBenefitGuarantyCorporationMember_CB4F8DF435A65F273E2107E551B283D7_terseLabel_en-US" xlink:label="lab_arnc_PensionBenefitGuarantyCorporationMember_CB4F8DF435A65F273E2107E551B283D7" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Pension Benefit Guaranty Corporation</link:label>
    <link:label id="lab_arnc_PensionBenefitGuarantyCorporationMember_CB4F8DF435A65F273E2107E551B283D7_label_en-US" xlink:label="lab_arnc_PensionBenefitGuarantyCorporationMember_CB4F8DF435A65F273E2107E551B283D7" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Pension Benefit Guaranty Corporation [Member]</link:label>
    <link:label id="lab_arnc_PensionBenefitGuarantyCorporationMember_CB4F8DF435A65F273E2107E551B283D7_documentation_en-US" xlink:label="lab_arnc_PensionBenefitGuarantyCorporationMember_CB4F8DF435A65F273E2107E551B283D7" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Pension Benefit Guaranty Corporation [Member]</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_PensionBenefitGuarantyCorporationMember" xlink:label="loc_arnc_PensionBenefitGuarantyCorporationMember_CB4F8DF435A65F273E2107E551B283D7" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_PensionBenefitGuarantyCorporationMember_CB4F8DF435A65F273E2107E551B283D7" xlink:to="lab_arnc_PensionBenefitGuarantyCorporationMember_CB4F8DF435A65F273E2107E551B283D7" xlink:type="arc" />
    <link:label id="lab_us-gaap_StatementScenarioAxis_2C3011A1522629FB687607D5A20BA5B7_terseLabel_en-US" xlink:label="lab_us-gaap_StatementScenarioAxis_2C3011A1522629FB687607D5A20BA5B7" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Scenario [Axis]</link:label>
    <link:label id="lab_us-gaap_StatementScenarioAxis_2C3011A1522629FB687607D5A20BA5B7_label_en-US" xlink:label="lab_us-gaap_StatementScenarioAxis_2C3011A1522629FB687607D5A20BA5B7" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Scenario [Axis]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_StatementScenarioAxis" xlink:label="loc_us-gaap_StatementScenarioAxis_2C3011A1522629FB687607D5A20BA5B7" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_StatementScenarioAxis_2C3011A1522629FB687607D5A20BA5B7" xlink:to="lab_us-gaap_StatementScenarioAxis_2C3011A1522629FB687607D5A20BA5B7" xlink:type="arc" />
    <link:label id="lab_us-gaap_ScenarioUnspecifiedDomain_0E4BE1772E05572AA45507D5A20B8D10_terseLabel_en-US" xlink:label="lab_us-gaap_ScenarioUnspecifiedDomain_0E4BE1772E05572AA45507D5A20B8D10" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Scenario, Unspecified [Domain]</link:label>
    <link:label id="lab_us-gaap_ScenarioUnspecifiedDomain_0E4BE1772E05572AA45507D5A20B8D10_label_en-US" xlink:label="lab_us-gaap_ScenarioUnspecifiedDomain_0E4BE1772E05572AA45507D5A20B8D10" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Scenario, Unspecified [Domain]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ScenarioUnspecifiedDomain" xlink:label="loc_us-gaap_ScenarioUnspecifiedDomain_0E4BE1772E05572AA45507D5A20B8D10" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScenarioUnspecifiedDomain_0E4BE1772E05572AA45507D5A20B8D10" xlink:to="lab_us-gaap_ScenarioUnspecifiedDomain_0E4BE1772E05572AA45507D5A20B8D10" xlink:type="arc" />
    <link:label id="lab_us-gaap_ScenarioForecastMember_C8A049DE4111B5CAA71407D5A20CB988_terseLabel_en-US" xlink:label="lab_us-gaap_ScenarioForecastMember_C8A049DE4111B5CAA71407D5A20CB988" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Scenario, Forecast</link:label>
    <link:label id="lab_us-gaap_ScenarioForecastMember_C8A049DE4111B5CAA71407D5A20CB988_label_en-US" xlink:label="lab_us-gaap_ScenarioForecastMember_C8A049DE4111B5CAA71407D5A20CB988" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Scenario, Forecast [Member]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ScenarioForecastMember" xlink:label="loc_us-gaap_ScenarioForecastMember_C8A049DE4111B5CAA71407D5A20CB988" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScenarioForecastMember_C8A049DE4111B5CAA71407D5A20CB988" xlink:to="lab_us-gaap_ScenarioForecastMember_C8A049DE4111B5CAA71407D5A20CB988" xlink:type="arc" />
    <link:label id="lab_us-gaap_RetirementPlanSponsorLocationAxis_410D343EC9553495F9AC07D5A20CB481_terseLabel_en-US" xlink:label="lab_us-gaap_RetirementPlanSponsorLocationAxis_410D343EC9553495F9AC07D5A20CB481" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Retirement Plan Sponsor Location [Axis]</link:label>
    <link:label id="lab_us-gaap_RetirementPlanSponsorLocationAxis_410D343EC9553495F9AC07D5A20CB481_label_en-US" xlink:label="lab_us-gaap_RetirementPlanSponsorLocationAxis_410D343EC9553495F9AC07D5A20CB481" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Retirement Plan Sponsor Location [Axis]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RetirementPlanSponsorLocationAxis" xlink:label="loc_us-gaap_RetirementPlanSponsorLocationAxis_410D343EC9553495F9AC07D5A20CB481" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RetirementPlanSponsorLocationAxis_410D343EC9553495F9AC07D5A20CB481" xlink:to="lab_us-gaap_RetirementPlanSponsorLocationAxis_410D343EC9553495F9AC07D5A20CB481" xlink:type="arc" />
    <link:label id="lab_us-gaap_RetirementPlanSponsorLocationDomain_8A10E43F6295EFF72F4B07D5A20C83BE_terseLabel_en-US" xlink:label="lab_us-gaap_RetirementPlanSponsorLocationDomain_8A10E43F6295EFF72F4B07D5A20C83BE" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Retirement Plan Sponsor Location [Domain]</link:label>
    <link:label id="lab_us-gaap_RetirementPlanSponsorLocationDomain_8A10E43F6295EFF72F4B07D5A20C83BE_label_en-US" xlink:label="lab_us-gaap_RetirementPlanSponsorLocationDomain_8A10E43F6295EFF72F4B07D5A20C83BE" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Retirement Plan Sponsor Location [Domain]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RetirementPlanSponsorLocationDomain" xlink:label="loc_us-gaap_RetirementPlanSponsorLocationDomain_8A10E43F6295EFF72F4B07D5A20C83BE" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RetirementPlanSponsorLocationDomain_8A10E43F6295EFF72F4B07D5A20C83BE" xlink:to="lab_us-gaap_RetirementPlanSponsorLocationDomain_8A10E43F6295EFF72F4B07D5A20C83BE" xlink:type="arc" />
    <link:label id="lab_country_US_397C924B7C8CFF740DEF07D5A20DF064_terseLabel_en-US" xlink:label="lab_country_US_397C924B7C8CFF740DEF07D5A20DF064" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">United States</link:label>
    <link:label id="lab_country_US_397C924B7C8CFF740DEF07D5A20DF064_label_en-US" xlink:label="lab_country_US_397C924B7C8CFF740DEF07D5A20DF064" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">UNITED STATES</link:label>
    <link:loc xlink:href="http://xbrl.sec.gov/country/2017/country-2017-01-31.xsd#country_US" xlink:label="loc_country_US_397C924B7C8CFF740DEF07D5A20DF064" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_country_US_397C924B7C8CFF740DEF07D5A20DF064" xlink:to="lab_country_US_397C924B7C8CFF740DEF07D5A20DF064" xlink:type="arc" />
    <link:label id="lab_us-gaap_RetirementPlanTypeAxis_755C209935232E6FACDC07D5A20D45E9_terseLabel_en-US" xlink:label="lab_us-gaap_RetirementPlanTypeAxis_755C209935232E6FACDC07D5A20D45E9" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Retirement Plan Type [Axis]</link:label>
    <link:label id="lab_us-gaap_RetirementPlanTypeAxis_755C209935232E6FACDC07D5A20D45E9_label_en-US" xlink:label="lab_us-gaap_RetirementPlanTypeAxis_755C209935232E6FACDC07D5A20D45E9" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Retirement Plan Type [Axis]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RetirementPlanTypeAxis" xlink:label="loc_us-gaap_RetirementPlanTypeAxis_755C209935232E6FACDC07D5A20D45E9" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RetirementPlanTypeAxis_755C209935232E6FACDC07D5A20D45E9" xlink:to="lab_us-gaap_RetirementPlanTypeAxis_755C209935232E6FACDC07D5A20D45E9" xlink:type="arc" />
    <link:label id="lab_us-gaap_RetirementPlanTypeDomain_E3FC3188EEE678A627C007D5A20D86F8_terseLabel_en-US" xlink:label="lab_us-gaap_RetirementPlanTypeDomain_E3FC3188EEE678A627C007D5A20D86F8" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Retirement Plan Type [Domain]</link:label>
    <link:label id="lab_us-gaap_RetirementPlanTypeDomain_E3FC3188EEE678A627C007D5A20D86F8_label_en-US" xlink:label="lab_us-gaap_RetirementPlanTypeDomain_E3FC3188EEE678A627C007D5A20D86F8" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Retirement Plan Type [Domain]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RetirementPlanTypeDomain" xlink:label="loc_us-gaap_RetirementPlanTypeDomain_E3FC3188EEE678A627C007D5A20D86F8" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RetirementPlanTypeDomain_E3FC3188EEE678A627C007D5A20D86F8" xlink:to="lab_us-gaap_RetirementPlanTypeDomain_E3FC3188EEE678A627C007D5A20D86F8" xlink:type="arc" />
    <link:label id="lab_us-gaap_PensionPlansDefinedBenefitMember_FD9CDD772817445E5D5F07D5A20E47A0_terseLabel_en-US" xlink:label="lab_us-gaap_PensionPlansDefinedBenefitMember_FD9CDD772817445E5D5F07D5A20E47A0" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Pension benefits paid</link:label>
    <link:label id="lab_us-gaap_PensionPlansDefinedBenefitMember_FD9CDD772817445E5D5F07D5A20E47A0_label_en-US" xlink:label="lab_us-gaap_PensionPlansDefinedBenefitMember_FD9CDD772817445E5D5F07D5A20E47A0" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Pension Plan [Member]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PensionPlansDefinedBenefitMember" xlink:label="loc_us-gaap_PensionPlansDefinedBenefitMember_FD9CDD772817445E5D5F07D5A20E47A0" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PensionPlansDefinedBenefitMember_FD9CDD772817445E5D5F07D5A20E47A0" xlink:to="lab_us-gaap_PensionPlansDefinedBenefitMember_FD9CDD772817445E5D5F07D5A20E47A0" xlink:type="arc" />
    <link:label id="lab_arnc_GrossPostretirementDefinedBenefitPlanMember_A6C4E38004AC7B7CB29707D5A20E40BC_terseLabel_en-US" xlink:label="lab_arnc_GrossPostretirementDefinedBenefitPlanMember_A6C4E38004AC7B7CB29707D5A20E40BC" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Gross Other post- retirement benefits</link:label>
    <link:label id="lab_arnc_GrossPostretirementDefinedBenefitPlanMember_A6C4E38004AC7B7CB29707D5A20E40BC_label_en-US" xlink:label="lab_arnc_GrossPostretirementDefinedBenefitPlanMember_A6C4E38004AC7B7CB29707D5A20E40BC" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Gross Postretirement Defined Benefit Plan [Member]</link:label>
    <link:label id="lab_arnc_GrossPostretirementDefinedBenefitPlanMember_A6C4E38004AC7B7CB29707D5A20E40BC_documentation_en-US" xlink:label="lab_arnc_GrossPostretirementDefinedBenefitPlanMember_A6C4E38004AC7B7CB29707D5A20E40BC" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Gross Postretirement Defined Benefit Plan [Member]</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_GrossPostretirementDefinedBenefitPlanMember" xlink:label="loc_arnc_GrossPostretirementDefinedBenefitPlanMember_A6C4E38004AC7B7CB29707D5A20E40BC" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_GrossPostretirementDefinedBenefitPlanMember_A6C4E38004AC7B7CB29707D5A20E40BC" xlink:to="lab_arnc_GrossPostretirementDefinedBenefitPlanMember_A6C4E38004AC7B7CB29707D5A20E40BC" xlink:type="arc" />
    <link:label id="lab_arnc_MedicarePartDSubsidyReceiptsMember_4B0F916FAD6EC701734B07D5A20E7FC1_terseLabel_en-US" xlink:label="lab_arnc_MedicarePartDSubsidyReceiptsMember_4B0F916FAD6EC701734B07D5A20E7FC1" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Medicare Part D subsidy receipts</link:label>
    <link:label id="lab_arnc_MedicarePartDSubsidyReceiptsMember_4B0F916FAD6EC701734B07D5A20E7FC1_label_en-US" xlink:label="lab_arnc_MedicarePartDSubsidyReceiptsMember_4B0F916FAD6EC701734B07D5A20E7FC1" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Medicare Part D Subsidy Receipts [Member]</link:label>
    <link:label id="lab_arnc_MedicarePartDSubsidyReceiptsMember_4B0F916FAD6EC701734B07D5A20E7FC1_documentation_en-US" xlink:label="lab_arnc_MedicarePartDSubsidyReceiptsMember_4B0F916FAD6EC701734B07D5A20E7FC1" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Medicare Part D Subsidy Receipts [Member]</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_MedicarePartDSubsidyReceiptsMember" xlink:label="loc_arnc_MedicarePartDSubsidyReceiptsMember_4B0F916FAD6EC701734B07D5A20E7FC1" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_MedicarePartDSubsidyReceiptsMember_4B0F916FAD6EC701734B07D5A20E7FC1" xlink:to="lab_arnc_MedicarePartDSubsidyReceiptsMember_4B0F916FAD6EC701734B07D5A20E7FC1" xlink:type="arc" />
    <link:label id="lab_arnc_NetOtherPostRetirementBenefitsMember_674D5E8E6EF58E019EE107D5A20E3927_terseLabel_en-US" xlink:label="lab_arnc_NetOtherPostRetirementBenefitsMember_674D5E8E6EF58E019EE107D5A20E3927" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Net Other post- retirement benefits</link:label>
    <link:label id="lab_arnc_NetOtherPostRetirementBenefitsMember_674D5E8E6EF58E019EE107D5A20E3927_label_en-US" xlink:label="lab_arnc_NetOtherPostRetirementBenefitsMember_674D5E8E6EF58E019EE107D5A20E3927" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Net Other Post Retirement Benefits [Member]</link:label>
    <link:label id="lab_arnc_NetOtherPostRetirementBenefitsMember_674D5E8E6EF58E019EE107D5A20E3927_documentation_en-US" xlink:label="lab_arnc_NetOtherPostRetirementBenefitsMember_674D5E8E6EF58E019EE107D5A20E3927" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Net Other Post-Retirement Benefits [Member]</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_NetOtherPostRetirementBenefitsMember" xlink:label="loc_arnc_NetOtherPostRetirementBenefitsMember_674D5E8E6EF58E019EE107D5A20E3927" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_NetOtherPostRetirementBenefitsMember_674D5E8E6EF58E019EE107D5A20E3927" xlink:to="lab_arnc_NetOtherPostRetirementBenefitsMember_674D5E8E6EF58E019EE107D5A20E3927" xlink:type="arc" />
    <link:label id="lab_us-gaap_DefinedBenefitPlanDisclosureLineItems_CACA2297C6612D82FED707D5A20FBF74_terseLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanDisclosureLineItems_CACA2297C6612D82FED707D5A20FBF74" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan Disclosure [Line Items]</link:label>
    <link:label id="lab_us-gaap_DefinedBenefitPlanDisclosureLineItems_CACA2297C6612D82FED707D5A20FBF74_label_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanDisclosureLineItems_CACA2297C6612D82FED707D5A20FBF74" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan Disclosure [Line Items]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DefinedBenefitPlanDisclosureLineItems" xlink:label="loc_us-gaap_DefinedBenefitPlanDisclosureLineItems_CACA2297C6612D82FED707D5A20FBF74" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanDisclosureLineItems_CACA2297C6612D82FED707D5A20FBF74" xlink:to="lab_us-gaap_DefinedBenefitPlanDisclosureLineItems_CACA2297C6612D82FED707D5A20FBF74" xlink:type="arc" />
    <link:label id="lab_us-gaap_PensionContributions_6FC5BEB7A8C12CBBB89C07D5A20FE366_terseLabel_en-US" xlink:label="lab_us-gaap_PensionContributions_6FC5BEB7A8C12CBBB89C07D5A20FE366" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Payment for pension benefits</link:label>
    <link:label id="lab_us-gaap_PensionContributions_6FC5BEB7A8C12CBBB89C07D5A20FE366_label_en-US" xlink:label="lab_us-gaap_PensionContributions_6FC5BEB7A8C12CBBB89C07D5A20FE366" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Payment for Pension Benefits</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PensionContributions" xlink:label="loc_us-gaap_PensionContributions_6FC5BEB7A8C12CBBB89C07D5A20FE366" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PensionContributions_6FC5BEB7A8C12CBBB89C07D5A20FE366" xlink:to="lab_us-gaap_PensionContributions_6FC5BEB7A8C12CBBB89C07D5A20FE366" xlink:type="arc" />
    <link:label id="lab_arnc_PaymentForPensionBenefitPlanInExcessOfMinimumRequired_422A93778F6DFDD25A2507D5A20F74C4_terseLabel_en-US" xlink:label="lab_arnc_PaymentForPensionBenefitPlanInExcessOfMinimumRequired_422A93778F6DFDD25A2507D5A20F74C4" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Payment for pension benefit plan in excess of minimum required</link:label>
    <link:label id="lab_arnc_PaymentForPensionBenefitPlanInExcessOfMinimumRequired_422A93778F6DFDD25A2507D5A20F74C4_label_en-US" xlink:label="lab_arnc_PaymentForPensionBenefitPlanInExcessOfMinimumRequired_422A93778F6DFDD25A2507D5A20F74C4" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Payment For Pension Benefit Plan In Excess Of Minimum Required</link:label>
    <link:label id="lab_arnc_PaymentForPensionBenefitPlanInExcessOfMinimumRequired_422A93778F6DFDD25A2507D5A20F74C4_documentation_en-US" xlink:label="lab_arnc_PaymentForPensionBenefitPlanInExcessOfMinimumRequired_422A93778F6DFDD25A2507D5A20F74C4" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Payment For Pension Benefit Plan In Excess Of Minimum Required</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_PaymentForPensionBenefitPlanInExcessOfMinimumRequired" xlink:label="loc_arnc_PaymentForPensionBenefitPlanInExcessOfMinimumRequired_422A93778F6DFDD25A2507D5A20F74C4" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_PaymentForPensionBenefitPlanInExcessOfMinimumRequired_422A93778F6DFDD25A2507D5A20F74C4" xlink:to="lab_arnc_PaymentForPensionBenefitPlanInExcessOfMinimumRequired_422A93778F6DFDD25A2507D5A20F74C4" xlink:type="arc" />
    <link:label id="lab_us-gaap_DefinedBenefitPlanExpectedFutureEmployerContributionsNextFiscalYear_5612789F91A993EDBE5C07E29F3DCA00_terseLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanExpectedFutureEmployerContributionsNextFiscalYear_5612789F91A993EDBE5C07E29F3DCA00" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Contribution next fiscal year</link:label>
    <link:label id="lab_us-gaap_DefinedBenefitPlanExpectedFutureEmployerContributionsNextFiscalYear_5612789F91A993EDBE5C07E29F3DCA00_label_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanExpectedFutureEmployerContributionsNextFiscalYear_5612789F91A993EDBE5C07E29F3DCA00" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Expected Future Employer Contributions, Next Fiscal Year</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DefinedBenefitPlanExpectedFutureEmployerContributionsNextFiscalYear" xlink:label="loc_us-gaap_DefinedBenefitPlanExpectedFutureEmployerContributionsNextFiscalYear_5612789F91A993EDBE5C07E29F3DCA00" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanExpectedFutureEmployerContributionsNextFiscalYear_5612789F91A993EDBE5C07E29F3DCA00" xlink:to="lab_us-gaap_DefinedBenefitPlanExpectedFutureEmployerContributionsNextFiscalYear_5612789F91A993EDBE5C07E29F3DCA00" xlink:type="arc" />
    <link:label id="lab_arnc_MinimumRequiredCashContributionToPensionPlan_15579800C7AD416A068307D5A20F5C4E_terseLabel_en-US" xlink:label="lab_arnc_MinimumRequiredCashContributionToPensionPlan_15579800C7AD416A068307D5A20F5C4E" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Minimum required cash contribution to pension plan</link:label>
    <link:label id="lab_arnc_MinimumRequiredCashContributionToPensionPlan_15579800C7AD416A068307D5A20F5C4E_label_en-US" xlink:label="lab_arnc_MinimumRequiredCashContributionToPensionPlan_15579800C7AD416A068307D5A20F5C4E" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Minimum Required Cash Contribution To Pension Plan</link:label>
    <link:label id="lab_arnc_MinimumRequiredCashContributionToPensionPlan_15579800C7AD416A068307D5A20F5C4E_documentation_en-US" xlink:label="lab_arnc_MinimumRequiredCashContributionToPensionPlan_15579800C7AD416A068307D5A20F5C4E" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Minimum required cash contribution to pension plan.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_MinimumRequiredCashContributionToPensionPlan" xlink:label="loc_arnc_MinimumRequiredCashContributionToPensionPlan_15579800C7AD416A068307D5A20F5C4E" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_MinimumRequiredCashContributionToPensionPlan_15579800C7AD416A068307D5A20F5C4E" xlink:to="lab_arnc_MinimumRequiredCashContributionToPensionPlan_15579800C7AD416A068307D5A20F5C4E" xlink:type="arc" />
    <link:label id="lab_arnc_CashContributionTermToPensionPlan_D5805FBE9CA7740F13B707D5A210A688_terseLabel_en-US" xlink:label="lab_arnc_CashContributionTermToPensionPlan_D5805FBE9CA7740F13B707D5A210A688" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Cash contribution term to pension plan</link:label>
    <link:label id="lab_arnc_CashContributionTermToPensionPlan_D5805FBE9CA7740F13B707D5A210A688_label_en-US" xlink:label="lab_arnc_CashContributionTermToPensionPlan_D5805FBE9CA7740F13B707D5A210A688" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Cash Contribution Term To Pension Plan</link:label>
    <link:label id="lab_arnc_CashContributionTermToPensionPlan_D5805FBE9CA7740F13B707D5A210A688_documentation_en-US" xlink:label="lab_arnc_CashContributionTermToPensionPlan_D5805FBE9CA7740F13B707D5A210A688" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Cash contribution term to pension plan.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_CashContributionTermToPensionPlan" xlink:label="loc_arnc_CashContributionTermToPensionPlan_D5805FBE9CA7740F13B707D5A210A688" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_CashContributionTermToPensionPlan_D5805FBE9CA7740F13B707D5A210A688" xlink:to="lab_arnc_CashContributionTermToPensionPlan_D5805FBE9CA7740F13B707D5A210A688" xlink:type="arc" />
    <link:label id="lab_arnc_NumberOfInstallmentMadeForCashContributionToPensionPlan_7BEE18B309DEBCEDDB3F07D5A2100D62_terseLabel_en-US" xlink:label="lab_arnc_NumberOfInstallmentMadeForCashContributionToPensionPlan_7BEE18B309DEBCEDDB3F07D5A2100D62" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Number of installment made for cash contribution to pension plan</link:label>
    <link:label id="lab_arnc_NumberOfInstallmentMadeForCashContributionToPensionPlan_7BEE18B309DEBCEDDB3F07D5A2100D62_label_en-US" xlink:label="lab_arnc_NumberOfInstallmentMadeForCashContributionToPensionPlan_7BEE18B309DEBCEDDB3F07D5A2100D62" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Number Of Installment made for cash contribution to pension plan</link:label>
    <link:label id="lab_arnc_NumberOfInstallmentMadeForCashContributionToPensionPlan_7BEE18B309DEBCEDDB3F07D5A2100D62_documentation_en-US" xlink:label="lab_arnc_NumberOfInstallmentMadeForCashContributionToPensionPlan_7BEE18B309DEBCEDDB3F07D5A2100D62" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Number of installment made for cash contribution to pension plan.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_NumberOfInstallmentMadeForCashContributionToPensionPlan" xlink:label="loc_arnc_NumberOfInstallmentMadeForCashContributionToPensionPlan_7BEE18B309DEBCEDDB3F07D5A2100D62" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_NumberOfInstallmentMadeForCashContributionToPensionPlan_7BEE18B309DEBCEDDB3F07D5A2100D62" xlink:to="lab_arnc_NumberOfInstallmentMadeForCashContributionToPensionPlan_7BEE18B309DEBCEDDB3F07D5A2100D62" xlink:type="arc" />
    <link:label id="lab_arnc_AggregateCashContributionToPensionPlan_E652176838C803FFE87907D5A210856F_terseLabel_en-US" xlink:label="lab_arnc_AggregateCashContributionToPensionPlan_E652176838C803FFE87907D5A210856F" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Aggregate cash contribution to pension plan</link:label>
    <link:label id="lab_arnc_AggregateCashContributionToPensionPlan_E652176838C803FFE87907D5A210856F_label_en-US" xlink:label="lab_arnc_AggregateCashContributionToPensionPlan_E652176838C803FFE87907D5A210856F" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Aggregate Cash Contribution To Pension Plan</link:label>
    <link:label id="lab_arnc_AggregateCashContributionToPensionPlan_E652176838C803FFE87907D5A210856F_documentation_en-US" xlink:label="lab_arnc_AggregateCashContributionToPensionPlan_E652176838C803FFE87907D5A210856F" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Aggregate cash contribution to pension plan.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_AggregateCashContributionToPensionPlan" xlink:label="loc_arnc_AggregateCashContributionToPensionPlan_E652176838C803FFE87907D5A210856F" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_AggregateCashContributionToPensionPlan_E652176838C803FFE87907D5A210856F" xlink:to="lab_arnc_AggregateCashContributionToPensionPlan_E652176838C803FFE87907D5A210856F" xlink:type="arc" />
    <link:label id="lab_us-gaap_PensionAndOtherPostretirementBenefitContributions_1776552A5E87FC02DE5507D5A21079DB_terseLabel_en-US" xlink:label="lab_us-gaap_PensionAndOtherPostretirementBenefitContributions_1776552A5E87FC02DE5507D5A21079DB" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Payment for pension and other postretirement benefits</link:label>
    <link:label id="lab_us-gaap_PensionAndOtherPostretirementBenefitContributions_1776552A5E87FC02DE5507D5A21079DB_label_en-US" xlink:label="lab_us-gaap_PensionAndOtherPostretirementBenefitContributions_1776552A5E87FC02DE5507D5A21079DB" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Payment for Pension and Other Postretirement Benefits</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PensionAndOtherPostretirementBenefitContributions" xlink:label="loc_us-gaap_PensionAndOtherPostretirementBenefitContributions_1776552A5E87FC02DE5507D5A21079DB" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PensionAndOtherPostretirementBenefitContributions_1776552A5E87FC02DE5507D5A21079DB" xlink:to="lab_us-gaap_PensionAndOtherPostretirementBenefitContributions_1776552A5E87FC02DE5507D5A21079DB" xlink:type="arc" />
    <link:label id="lab_us-gaap_DefinedBenefitPlanEstimatedFutureBenefitPaymentsAbstract_833192FC92E9CF401F9507D5A2111B4D_terseLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanEstimatedFutureBenefitPaymentsAbstract_833192FC92E9CF401F9507D5A2111B4D" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Expected Future Benefit Payment [Abstract]</link:label>
    <link:label id="lab_us-gaap_DefinedBenefitPlanEstimatedFutureBenefitPaymentsAbstract_833192FC92E9CF401F9507D5A2111B4D_label_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanEstimatedFutureBenefitPaymentsAbstract_833192FC92E9CF401F9507D5A2111B4D" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Expected Future Benefit Payment [Abstract]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DefinedBenefitPlanEstimatedFutureBenefitPaymentsAbstract" xlink:label="loc_us-gaap_DefinedBenefitPlanEstimatedFutureBenefitPaymentsAbstract_833192FC92E9CF401F9507D5A2111B4D" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanEstimatedFutureBenefitPaymentsAbstract_833192FC92E9CF401F9507D5A2111B4D" xlink:to="lab_us-gaap_DefinedBenefitPlanEstimatedFutureBenefitPaymentsAbstract_833192FC92E9CF401F9507D5A2111B4D" xlink:type="arc" />
    <link:label id="lab_us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsNextTwelveMonths_5EF097955242F5EA013407D5A21104AB_terseLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsNextTwelveMonths_5EF097955242F5EA013407D5A21104AB" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">2019</link:label>
    <link:label id="lab_us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsNextTwelveMonths_5EF097955242F5EA013407D5A21104AB_label_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsNextTwelveMonths_5EF097955242F5EA013407D5A21104AB" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Expected Future Benefit Payment, Next Twelve Months</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsNextTwelveMonths" xlink:label="loc_us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsNextTwelveMonths_5EF097955242F5EA013407D5A21104AB" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsNextTwelveMonths_5EF097955242F5EA013407D5A21104AB" xlink:to="lab_us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsNextTwelveMonths_5EF097955242F5EA013407D5A21104AB" xlink:type="arc" />
    <link:label id="lab_us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearTwo_8DC8FE93EE6D5AD5D19D07D5A211FBC4_terseLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearTwo_8DC8FE93EE6D5AD5D19D07D5A211FBC4" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">2020</link:label>
    <link:label id="lab_us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearTwo_8DC8FE93EE6D5AD5D19D07D5A211FBC4_label_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearTwo_8DC8FE93EE6D5AD5D19D07D5A211FBC4" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Expected Future Benefit Payment, Year Two</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearTwo" xlink:label="loc_us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearTwo_8DC8FE93EE6D5AD5D19D07D5A211FBC4" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearTwo_8DC8FE93EE6D5AD5D19D07D5A211FBC4" xlink:to="lab_us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearTwo_8DC8FE93EE6D5AD5D19D07D5A211FBC4" xlink:type="arc" />
    <link:label id="lab_us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearThree_E976AD422C35665602AA07D5A211BB35_terseLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearThree_E976AD422C35665602AA07D5A211BB35" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">2021</link:label>
    <link:label id="lab_us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearThree_E976AD422C35665602AA07D5A211BB35_label_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearThree_E976AD422C35665602AA07D5A211BB35" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Expected Future Benefit Payment, Year Three</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearThree" xlink:label="loc_us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearThree_E976AD422C35665602AA07D5A211BB35" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearThree_E976AD422C35665602AA07D5A211BB35" xlink:to="lab_us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearThree_E976AD422C35665602AA07D5A211BB35" xlink:type="arc" />
    <link:label id="lab_us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFour_01A633057E475EAED6F707D5A2129C15_terseLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFour_01A633057E475EAED6F707D5A2129C15" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">2022</link:label>
    <link:label id="lab_us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFour_01A633057E475EAED6F707D5A2129C15_label_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFour_01A633057E475EAED6F707D5A2129C15" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Expected Future Benefit Payment, Year Four</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFour" xlink:label="loc_us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFour_01A633057E475EAED6F707D5A2129C15" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFour_01A633057E475EAED6F707D5A2129C15" xlink:to="lab_us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFour_01A633057E475EAED6F707D5A2129C15" xlink:type="arc" />
    <link:label id="lab_us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFive_6FA8140D76A99867EE7607D5A212EF40_terseLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFive_6FA8140D76A99867EE7607D5A212EF40" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">2023</link:label>
    <link:label id="lab_us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFive_6FA8140D76A99867EE7607D5A212EF40_label_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFive_6FA8140D76A99867EE7607D5A212EF40" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Expected Future Benefit Payment, Year Five</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFive" xlink:label="loc_us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFive_6FA8140D76A99867EE7607D5A212EF40" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFive_6FA8140D76A99867EE7607D5A212EF40" xlink:to="lab_us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFive_6FA8140D76A99867EE7607D5A212EF40" xlink:type="arc" />
    <link:label id="lab_us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsFiveFiscalYearsThereafter_BEFE273564B80C9B0F0E07D5A2123D8D_terseLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsFiveFiscalYearsThereafter_BEFE273564B80C9B0F0E07D5A2123D8D" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Thereafter</link:label>
    <link:label id="lab_us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsFiveFiscalYearsThereafter_BEFE273564B80C9B0F0E07D5A2123D8D_label_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsFiveFiscalYearsThereafter_BEFE273564B80C9B0F0E07D5A2123D8D" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Expected Future Benefit Payment, Five Fiscal Years Thereafter</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsFiveFiscalYearsThereafter" xlink:label="loc_us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsFiveFiscalYearsThereafter_BEFE273564B80C9B0F0E07D5A2123D8D" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsFiveFiscalYearsThereafter_BEFE273564B80C9B0F0E07D5A2123D8D" xlink:to="lab_us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsFiveFiscalYearsThereafter_BEFE273564B80C9B0F0E07D5A2123D8D" xlink:type="arc" />
    <link:label id="lab_arnc_DefinedBenefitPlanExpectedFutureBenefitPayments_FC15BC81A1C194966C9E07D5A212F3B4_totalLabel_en-US" xlink:label="lab_arnc_DefinedBenefitPlanExpectedFutureBenefitPayments_FC15BC81A1C194966C9E07D5A212F3B4" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Total benefit payments</link:label>
    <link:label id="lab_arnc_DefinedBenefitPlanExpectedFutureBenefitPayments_FC15BC81A1C194966C9E07D5A212F3B4_label_en-US" xlink:label="lab_arnc_DefinedBenefitPlanExpectedFutureBenefitPayments_FC15BC81A1C194966C9E07D5A212F3B4" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan Expected Future Benefit Payments</link:label>
    <link:label id="lab_arnc_DefinedBenefitPlanExpectedFutureBenefitPayments_FC15BC81A1C194966C9E07D5A212F3B4_documentation_en-US" xlink:label="lab_arnc_DefinedBenefitPlanExpectedFutureBenefitPayments_FC15BC81A1C194966C9E07D5A212F3B4" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Defined benefit plan expected future benefit payments.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_DefinedBenefitPlanExpectedFutureBenefitPayments" xlink:label="loc_arnc_DefinedBenefitPlanExpectedFutureBenefitPayments_FC15BC81A1C194966C9E07D5A212F3B4" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_DefinedBenefitPlanExpectedFutureBenefitPayments_FC15BC81A1C194966C9E07D5A212F3B4" xlink:to="lab_arnc_DefinedBenefitPlanExpectedFutureBenefitPayments_FC15BC81A1C194966C9E07D5A212F3B4" xlink:type="arc" />
    <link:label id="lab_us-gaap_DefinedContributionPlanCostRecognized_BED3A68AED19E94F334607D5A212FF48_terseLabel_en-US" xlink:label="lab_us-gaap_DefinedContributionPlanCostRecognized_BED3A68AED19E94F334607D5A212FF48" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Expenses related to defined contribution plan</link:label>
    <link:label id="lab_us-gaap_DefinedContributionPlanCostRecognized_BED3A68AED19E94F334607D5A212FF48_label_en-US" xlink:label="lab_us-gaap_DefinedContributionPlanCostRecognized_BED3A68AED19E94F334607D5A212FF48" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Contribution Plan, Cost</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DefinedContributionPlanCostRecognized" xlink:label="loc_us-gaap_DefinedContributionPlanCostRecognized_BED3A68AED19E94F334607D5A212FF48" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedContributionPlanCostRecognized_BED3A68AED19E94F334607D5A212FF48" xlink:to="lab_us-gaap_DefinedContributionPlanCostRecognized_BED3A68AED19E94F334607D5A212FF48" xlink:type="arc" />
    <link:label id="lab_us-gaap_DebtDisclosureAbstract_C7414622DD56D079DE669A1859AB0677_label_en-US" xlink:label="lab_us-gaap_DebtDisclosureAbstract_C7414622DD56D079DE669A1859AB0677" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Debt Disclosure [Abstract]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DebtDisclosureAbstract" xlink:label="loc_us-gaap_DebtDisclosureAbstract_C7414622DD56D079DE669A1859AB0677" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DebtDisclosureAbstract_C7414622DD56D079DE669A1859AB0677" xlink:to="lab_us-gaap_DebtDisclosureAbstract_C7414622DD56D079DE669A1859AB0677" xlink:type="arc" />
    <link:label id="lab_arnc_InterestCostComponentsDisclosureTextBlock_C5189578DEA673488CFE9A1859ABDCB8_terseLabel_en-US" xlink:label="lab_arnc_InterestCostComponentsDisclosureTextBlock_C5189578DEA673488CFE9A1859ABDCB8" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Interest Cost Components</link:label>
    <link:label id="lab_arnc_InterestCostComponentsDisclosureTextBlock_C5189578DEA673488CFE9A1859ABDCB8_label_en-US" xlink:label="lab_arnc_InterestCostComponentsDisclosureTextBlock_C5189578DEA673488CFE9A1859ABDCB8" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Interest Cost Components Disclosure [Text Block]</link:label>
    <link:label id="lab_arnc_InterestCostComponentsDisclosureTextBlock_C5189578DEA673488CFE9A1859ABDCB8_documentation_en-US" xlink:label="lab_arnc_InterestCostComponentsDisclosureTextBlock_C5189578DEA673488CFE9A1859ABDCB8" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Interest Cost Components Disclosure [Text Block]</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_InterestCostComponentsDisclosureTextBlock" xlink:label="loc_arnc_InterestCostComponentsDisclosureTextBlock_C5189578DEA673488CFE9A1859ABDCB8" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_InterestCostComponentsDisclosureTextBlock_C5189578DEA673488CFE9A1859ABDCB8" xlink:to="lab_arnc_InterestCostComponentsDisclosureTextBlock_C5189578DEA673488CFE9A1859ABDCB8" xlink:type="arc" />
    <link:label id="lab_us-gaap_PensionPlansDefinedBenefitMember_B76149DC8CAEE4EA9C1F06E20DA8F4F1_verboseLabel_en-US" xlink:label="lab_us-gaap_PensionPlansDefinedBenefitMember_B76149DC8CAEE4EA9C1F06E20DA8F4F1" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Pension benefits</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PensionPlansDefinedBenefitMember" xlink:label="loc_us-gaap_PensionPlansDefinedBenefitMember_B76149DC8CAEE4EA9C1F06E20DA8F4F1" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PensionPlansDefinedBenefitMember_B76149DC8CAEE4EA9C1F06E20DA8F4F1" xlink:to="lab_us-gaap_PensionPlansDefinedBenefitMember_B76149DC8CAEE4EA9C1F06E20DA8F4F1" xlink:type="arc" />
    <link:label id="lab_us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember_52B96A4B66F7A022ACED06E20DA80697_terseLabel_en-US" xlink:label="lab_us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember_52B96A4B66F7A022ACED06E20DA80697" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Other postretirement benefits</link:label>
    <link:label id="lab_us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember_52B96A4B66F7A022ACED06E20DA80697_label_en-US" xlink:label="lab_us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember_52B96A4B66F7A022ACED06E20DA80697" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Other Postretirement Benefits Plan [Member]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember" xlink:label="loc_us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember_52B96A4B66F7A022ACED06E20DA80697" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember_52B96A4B66F7A022ACED06E20DA80697" xlink:to="lab_us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember_52B96A4B66F7A022ACED06E20DA80697" xlink:type="arc" />
    <link:label id="lab_us-gaap_DefinedBenefitPlanChangeInBenefitObligationRollForward_48572CB2486835193BAA06E20DA9C7FE_terseLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanChangeInBenefitObligationRollForward_48572CB2486835193BAA06E20DA9C7FE" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Change in benefit obligation</link:label>
    <link:label id="lab_us-gaap_DefinedBenefitPlanChangeInBenefitObligationRollForward_48572CB2486835193BAA06E20DA9C7FE_label_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanChangeInBenefitObligationRollForward_48572CB2486835193BAA06E20DA9C7FE" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DefinedBenefitPlanChangeInBenefitObligationRollForward" xlink:label="loc_us-gaap_DefinedBenefitPlanChangeInBenefitObligationRollForward_48572CB2486835193BAA06E20DA9C7FE" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanChangeInBenefitObligationRollForward_48572CB2486835193BAA06E20DA9C7FE" xlink:to="lab_us-gaap_DefinedBenefitPlanChangeInBenefitObligationRollForward_48572CB2486835193BAA06E20DA9C7FE" xlink:type="arc" />
    <link:label id="lab_us-gaap_DefinedBenefitPlanBenefitObligation_D42853578AF359A6E93606E20DA9A7B4_periodStartLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanBenefitObligation_D42853578AF359A6E93606E20DA9A7B4" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel" xlink:type="resource" xml:lang="en-US">Benefit obligation at beginning of year</link:label>
    <link:label id="lab_us-gaap_DefinedBenefitPlanBenefitObligation_D42853578AF359A6E93606E20DA9A7B4_label_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanBenefitObligation_D42853578AF359A6E93606E20DA9A7B4" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Benefit Obligation</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DefinedBenefitPlanBenefitObligation" xlink:label="loc_us-gaap_DefinedBenefitPlanBenefitObligation_D42853578AF359A6E93606E20DA9A7B4" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanBenefitObligation_D42853578AF359A6E93606E20DA9A7B4" xlink:to="lab_us-gaap_DefinedBenefitPlanBenefitObligation_D42853578AF359A6E93606E20DA9A7B4" xlink:type="arc" />
    <link:label id="lab_us-gaap_DefinedBenefitPlanServiceCost_BB5AA2948BE8028EFD4D06E20DA95518_terseLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanServiceCost_BB5AA2948BE8028EFD4D06E20DA95518" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Service cost</link:label>
    <link:label id="lab_us-gaap_DefinedBenefitPlanServiceCost_BB5AA2948BE8028EFD4D06E20DA95518_label_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanServiceCost_BB5AA2948BE8028EFD4D06E20DA95518" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Service Cost</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DefinedBenefitPlanServiceCost" xlink:label="loc_us-gaap_DefinedBenefitPlanServiceCost_BB5AA2948BE8028EFD4D06E20DA95518" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanServiceCost_BB5AA2948BE8028EFD4D06E20DA95518" xlink:to="lab_us-gaap_DefinedBenefitPlanServiceCost_BB5AA2948BE8028EFD4D06E20DA95518" xlink:type="arc" />
    <link:label id="lab_us-gaap_DefinedBenefitPlanInterestCost_34301B94F251FBD1811E06E20DA94E68_terseLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanInterestCost_34301B94F251FBD1811E06E20DA94E68" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Interest cost</link:label>
    <link:label id="lab_us-gaap_DefinedBenefitPlanInterestCost_34301B94F251FBD1811E06E20DA94E68_label_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanInterestCost_34301B94F251FBD1811E06E20DA94E68" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Interest Cost</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DefinedBenefitPlanInterestCost" xlink:label="loc_us-gaap_DefinedBenefitPlanInterestCost_34301B94F251FBD1811E06E20DA94E68" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanInterestCost_34301B94F251FBD1811E06E20DA94E68" xlink:to="lab_us-gaap_DefinedBenefitPlanInterestCost_34301B94F251FBD1811E06E20DA94E68" xlink:type="arc" />
    <link:label id="lab_us-gaap_DefinedBenefitPlanPlanAmendments_AB26C63D99C3A1EA32AC06E20DAA6BB9_terseLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanPlanAmendments_AB26C63D99C3A1EA32AC06E20DAA6BB9" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Amendments</link:label>
    <link:label id="lab_us-gaap_DefinedBenefitPlanPlanAmendments_AB26C63D99C3A1EA32AC06E20DAA6BB9_label_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanPlanAmendments_AB26C63D99C3A1EA32AC06E20DAA6BB9" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Benefit Obligation, Increase (Decrease) for Plan Amendment</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DefinedBenefitPlanPlanAmendments" xlink:label="loc_us-gaap_DefinedBenefitPlanPlanAmendments_AB26C63D99C3A1EA32AC06E20DAA6BB9" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanPlanAmendments_AB26C63D99C3A1EA32AC06E20DAA6BB9" xlink:to="lab_us-gaap_DefinedBenefitPlanPlanAmendments_AB26C63D99C3A1EA32AC06E20DAA6BB9" xlink:type="arc" />
    <link:label id="lab_us-gaap_DefinedBenefitPlanActuarialGainLoss_995B09D5A48D7D265ABC06E20DAA0C5C_negatedTerseLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanActuarialGainLoss_995B09D5A48D7D265ABC06E20DAA0C5C" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:type="resource" xml:lang="en-US">Actuarial (gains) losses</link:label>
    <link:label id="lab_us-gaap_DefinedBenefitPlanActuarialGainLoss_995B09D5A48D7D265ABC06E20DAA0C5C_label_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanActuarialGainLoss_995B09D5A48D7D265ABC06E20DAA0C5C" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Benefit Obligation, Actuarial Gain (Loss)</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DefinedBenefitPlanActuarialGainLoss" xlink:label="loc_us-gaap_DefinedBenefitPlanActuarialGainLoss_995B09D5A48D7D265ABC06E20DAA0C5C" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanActuarialGainLoss_995B09D5A48D7D265ABC06E20DAA0C5C" xlink:to="lab_us-gaap_DefinedBenefitPlanActuarialGainLoss_995B09D5A48D7D265ABC06E20DAA0C5C" xlink:type="arc" />
    <link:label id="lab_us-gaap_DefinedBenefitPlanSettlementsBenefitObligation_92BB1A75FEEBD53A3CBF06E20DAA1CE7_negatedLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanSettlementsBenefitObligation_92BB1A75FEEBD53A3CBF06E20DAA1CE7" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xml:lang="en-US">Settlements</link:label>
    <link:label id="lab_us-gaap_DefinedBenefitPlanSettlementsBenefitObligation_92BB1A75FEEBD53A3CBF06E20DAA1CE7_label_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanSettlementsBenefitObligation_92BB1A75FEEBD53A3CBF06E20DAA1CE7" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Benefit Obligation, (Increase) Decrease for Settlement</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DefinedBenefitPlanSettlementsBenefitObligation" xlink:label="loc_us-gaap_DefinedBenefitPlanSettlementsBenefitObligation_92BB1A75FEEBD53A3CBF06E20DAA1CE7" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanSettlementsBenefitObligation_92BB1A75FEEBD53A3CBF06E20DAA1CE7" xlink:to="lab_us-gaap_DefinedBenefitPlanSettlementsBenefitObligation_92BB1A75FEEBD53A3CBF06E20DAA1CE7" xlink:type="arc" />
    <link:label id="lab_us-gaap_DefinedBenefitPlanCurtailments_2D3FF2FB6F7C1D5A27FF06E20DAA32A5_negatedTerseLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanCurtailments_2D3FF2FB6F7C1D5A27FF06E20DAA32A5" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:type="resource" xml:lang="en-US">Curtailments</link:label>
    <link:label id="lab_us-gaap_DefinedBenefitPlanCurtailments_2D3FF2FB6F7C1D5A27FF06E20DAA32A5_label_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanCurtailments_2D3FF2FB6F7C1D5A27FF06E20DAA32A5" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Benefit Obligation, (Increase) Decrease for Curtailment</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DefinedBenefitPlanCurtailments" xlink:label="loc_us-gaap_DefinedBenefitPlanCurtailments_2D3FF2FB6F7C1D5A27FF06E20DAA32A5" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanCurtailments_2D3FF2FB6F7C1D5A27FF06E20DAA32A5" xlink:to="lab_us-gaap_DefinedBenefitPlanCurtailments_2D3FF2FB6F7C1D5A27FF06E20DAA32A5" xlink:type="arc" />
    <link:label id="lab_us-gaap_DefinedBenefitPlanBenefitObligationBenefitsPaid_D4EB8AD3DE8275F8FAD906E20DAAC24A_negatedLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanBenefitObligationBenefitsPaid_D4EB8AD3DE8275F8FAD906E20DAAC24A" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xml:lang="en-US">Benefits paid</link:label>
    <link:label id="lab_us-gaap_DefinedBenefitPlanBenefitObligationBenefitsPaid_D4EB8AD3DE8275F8FAD906E20DAAC24A_label_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanBenefitObligationBenefitsPaid_D4EB8AD3DE8275F8FAD906E20DAAC24A" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Benefit Obligation, Benefits Paid</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DefinedBenefitPlanBenefitObligationBenefitsPaid" xlink:label="loc_us-gaap_DefinedBenefitPlanBenefitObligationBenefitsPaid_D4EB8AD3DE8275F8FAD906E20DAAC24A" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanBenefitObligationBenefitsPaid_D4EB8AD3DE8275F8FAD906E20DAAC24A" xlink:to="lab_us-gaap_DefinedBenefitPlanBenefitObligationBenefitsPaid_D4EB8AD3DE8275F8FAD906E20DAAC24A" xlink:type="arc" />
    <link:label id="lab_us-gaap_DefinedBenefitPlanBenefitObligationPrescriptionDrugSubsidyReceipt_0057C859058E5717947206E20DAABCDC_terseLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanBenefitObligationPrescriptionDrugSubsidyReceipt_0057C859058E5717947206E20DAABCDC" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Medicare Part D subsidy receipts</link:label>
    <link:label id="lab_us-gaap_DefinedBenefitPlanBenefitObligationPrescriptionDrugSubsidyReceipt_0057C859058E5717947206E20DAABCDC_label_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanBenefitObligationPrescriptionDrugSubsidyReceipt_0057C859058E5717947206E20DAABCDC" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Benefit Obligation, Prescription Drug Subsidy Receipt</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DefinedBenefitPlanBenefitObligationPrescriptionDrugSubsidyReceipt" xlink:label="loc_us-gaap_DefinedBenefitPlanBenefitObligationPrescriptionDrugSubsidyReceipt_0057C859058E5717947206E20DAABCDC" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanBenefitObligationPrescriptionDrugSubsidyReceipt_0057C859058E5717947206E20DAABCDC" xlink:to="lab_us-gaap_DefinedBenefitPlanBenefitObligationPrescriptionDrugSubsidyReceipt_0057C859058E5717947206E20DAABCDC" xlink:type="arc" />
    <link:label id="lab_us-gaap_DefinedBenefitPlanForeignCurrencyExchangeRateChangesBenefitObligation_D071A5FFA61289EB5B1D06E20DABE0B8_negatedLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanForeignCurrencyExchangeRateChangesBenefitObligation_D071A5FFA61289EB5B1D06E20DABE0B8" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xml:lang="en-US">Foreign currency translation impact</link:label>
    <link:label id="lab_us-gaap_DefinedBenefitPlanForeignCurrencyExchangeRateChangesBenefitObligation_D071A5FFA61289EB5B1D06E20DABE0B8_label_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanForeignCurrencyExchangeRateChangesBenefitObligation_D071A5FFA61289EB5B1D06E20DABE0B8" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Benefit Obligation, Foreign Currency Translation Gain (Loss)</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DefinedBenefitPlanForeignCurrencyExchangeRateChangesBenefitObligation" xlink:label="loc_us-gaap_DefinedBenefitPlanForeignCurrencyExchangeRateChangesBenefitObligation_D071A5FFA61289EB5B1D06E20DABE0B8" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanForeignCurrencyExchangeRateChangesBenefitObligation_D071A5FFA61289EB5B1D06E20DABE0B8" xlink:to="lab_us-gaap_DefinedBenefitPlanForeignCurrencyExchangeRateChangesBenefitObligation_D071A5FFA61289EB5B1D06E20DABE0B8" xlink:type="arc" />
    <link:label id="lab_us-gaap_DefinedBenefitPlanBenefitObligation_824514CCA5A5D813E8B506E20DAB081F_periodEndLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanBenefitObligation_824514CCA5A5D813E8B506E20DAB081F" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel" xlink:type="resource" xml:lang="en-US">Benefit obligation at end of year</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DefinedBenefitPlanBenefitObligation" xlink:label="loc_us-gaap_DefinedBenefitPlanBenefitObligation_824514CCA5A5D813E8B506E20DAB081F" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanBenefitObligation_824514CCA5A5D813E8B506E20DAB081F" xlink:to="lab_us-gaap_DefinedBenefitPlanBenefitObligation_824514CCA5A5D813E8B506E20DAB081F" xlink:type="arc" />
    <link:label id="lab_us-gaap_DefinedBenefitPlanChangeInFairValueOfPlanAssetsRollForward_C4F2B4B493FDD5D4773306E20DAB4985_terseLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanChangeInFairValueOfPlanAssetsRollForward_C4F2B4B493FDD5D4773306E20DAB4985" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Change in plan assets</link:label>
    <link:label id="lab_us-gaap_DefinedBenefitPlanChangeInFairValueOfPlanAssetsRollForward_C4F2B4B493FDD5D4773306E20DAB4985_label_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanChangeInFairValueOfPlanAssetsRollForward_C4F2B4B493FDD5D4773306E20DAB4985" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DefinedBenefitPlanChangeInFairValueOfPlanAssetsRollForward" xlink:label="loc_us-gaap_DefinedBenefitPlanChangeInFairValueOfPlanAssetsRollForward_C4F2B4B493FDD5D4773306E20DAB4985" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanChangeInFairValueOfPlanAssetsRollForward_C4F2B4B493FDD5D4773306E20DAB4985" xlink:to="lab_us-gaap_DefinedBenefitPlanChangeInFairValueOfPlanAssetsRollForward_C4F2B4B493FDD5D4773306E20DAB4985" xlink:type="arc" />
    <link:label id="lab_us-gaap_DefinedBenefitPlanFairValueOfPlanAssets_83196F814070078B096406E20DAB9A23_periodStartLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanFairValueOfPlanAssets_83196F814070078B096406E20DAB9A23" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel" xlink:type="resource" xml:lang="en-US">Fair value of plan assets at beginning of year</link:label>
    <link:label id="lab_us-gaap_DefinedBenefitPlanFairValueOfPlanAssets_83196F814070078B096406E20DAB9A23_label_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanFairValueOfPlanAssets_83196F814070078B096406E20DAB9A23" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Plan Assets, Amount</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DefinedBenefitPlanFairValueOfPlanAssets" xlink:label="loc_us-gaap_DefinedBenefitPlanFairValueOfPlanAssets_83196F814070078B096406E20DAB9A23" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanFairValueOfPlanAssets_83196F814070078B096406E20DAB9A23" xlink:to="lab_us-gaap_DefinedBenefitPlanFairValueOfPlanAssets_83196F814070078B096406E20DAB9A23" xlink:type="arc" />
    <link:label id="lab_us-gaap_DefinedBenefitPlanActualReturnOnPlanAssets_365A7DED608E289728F706E20DAB10AD_terseLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanActualReturnOnPlanAssets_365A7DED608E289728F706E20DAB10AD" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Actual return on plan assets</link:label>
    <link:label id="lab_us-gaap_DefinedBenefitPlanActualReturnOnPlanAssets_365A7DED608E289728F706E20DAB10AD_label_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanActualReturnOnPlanAssets_365A7DED608E289728F706E20DAB10AD" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Plan Assets, Increase (Decrease) for Actual Return (Loss)</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DefinedBenefitPlanActualReturnOnPlanAssets" xlink:label="loc_us-gaap_DefinedBenefitPlanActualReturnOnPlanAssets_365A7DED608E289728F706E20DAB10AD" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanActualReturnOnPlanAssets_365A7DED608E289728F706E20DAB10AD" xlink:to="lab_us-gaap_DefinedBenefitPlanActualReturnOnPlanAssets_365A7DED608E289728F706E20DAB10AD" xlink:type="arc" />
    <link:label id="lab_us-gaap_DefinedBenefitPlanContributionsByEmployer_83B566B281A512E992D606E20DABA636_terseLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanContributionsByEmployer_83B566B281A512E992D606E20DABA636" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Employer contributions</link:label>
    <link:label id="lab_us-gaap_DefinedBenefitPlanContributionsByEmployer_83B566B281A512E992D606E20DABA636_label_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanContributionsByEmployer_83B566B281A512E992D606E20DABA636" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Plan Assets, Contributions by Employer</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DefinedBenefitPlanContributionsByEmployer" xlink:label="loc_us-gaap_DefinedBenefitPlanContributionsByEmployer_83B566B281A512E992D606E20DABA636" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanContributionsByEmployer_83B566B281A512E992D606E20DABA636" xlink:to="lab_us-gaap_DefinedBenefitPlanContributionsByEmployer_83B566B281A512E992D606E20DABA636" xlink:type="arc" />
    <link:label id="lab_us-gaap_DefinedBenefitPlanPlanAssetsBenefitsPaid_DC1BC81809BEA6DCE8B906E20DAC4BC6_negatedLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanPlanAssetsBenefitsPaid_DC1BC81809BEA6DCE8B906E20DAC4BC6" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xml:lang="en-US">Benefits paid</link:label>
    <link:label id="lab_us-gaap_DefinedBenefitPlanPlanAssetsBenefitsPaid_DC1BC81809BEA6DCE8B906E20DAC4BC6_label_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanPlanAssetsBenefitsPaid_DC1BC81809BEA6DCE8B906E20DAC4BC6" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Plan Assets, Benefits Paid</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DefinedBenefitPlanPlanAssetsBenefitsPaid" xlink:label="loc_us-gaap_DefinedBenefitPlanPlanAssetsBenefitsPaid_DC1BC81809BEA6DCE8B906E20DAC4BC6" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanPlanAssetsBenefitsPaid_DC1BC81809BEA6DCE8B906E20DAC4BC6" xlink:to="lab_us-gaap_DefinedBenefitPlanPlanAssetsBenefitsPaid_DC1BC81809BEA6DCE8B906E20DAC4BC6" xlink:type="arc" />
    <link:label id="lab_us-gaap_DefinedBenefitPlanAdministrationExpenses_C68DB1F1D403C87CC8AA06E20DAC439F_negatedLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanAdministrationExpenses_C68DB1F1D403C87CC8AA06E20DAC439F" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xml:lang="en-US">Administrative expenses</link:label>
    <link:label id="lab_us-gaap_DefinedBenefitPlanAdministrationExpenses_C68DB1F1D403C87CC8AA06E20DAC439F_label_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanAdministrationExpenses_C68DB1F1D403C87CC8AA06E20DAC439F" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Plan Assets, Administration Expense</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DefinedBenefitPlanAdministrationExpenses" xlink:label="loc_us-gaap_DefinedBenefitPlanAdministrationExpenses_C68DB1F1D403C87CC8AA06E20DAC439F" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanAdministrationExpenses_C68DB1F1D403C87CC8AA06E20DAC439F" xlink:to="lab_us-gaap_DefinedBenefitPlanAdministrationExpenses_C68DB1F1D403C87CC8AA06E20DAC439F" xlink:type="arc" />
    <link:label id="lab_us-gaap_DefinedBenefitPlanSettlementsPlanAssets_0042EF151327C90C59B506E20DAC90EB_negatedLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanSettlementsPlanAssets_0042EF151327C90C59B506E20DAC90EB" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xml:lang="en-US">Settlements</link:label>
    <link:label id="lab_us-gaap_DefinedBenefitPlanSettlementsPlanAssets_0042EF151327C90C59B506E20DAC90EB_label_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanSettlementsPlanAssets_0042EF151327C90C59B506E20DAC90EB" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Plan Assets, Payment for Settlement</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DefinedBenefitPlanSettlementsPlanAssets" xlink:label="loc_us-gaap_DefinedBenefitPlanSettlementsPlanAssets_0042EF151327C90C59B506E20DAC90EB" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanSettlementsPlanAssets_0042EF151327C90C59B506E20DAC90EB" xlink:to="lab_us-gaap_DefinedBenefitPlanSettlementsPlanAssets_0042EF151327C90C59B506E20DAC90EB" xlink:type="arc" />
    <link:label id="lab_us-gaap_DefinedBenefitPlanPlanAssetsForeignCurrencyTranslationGainLoss_26FE67C65E8A9C3DBB2406E20DACACFA_negatedLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanPlanAssetsForeignCurrencyTranslationGainLoss_26FE67C65E8A9C3DBB2406E20DACACFA" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xml:lang="en-US">Foreign currency translation impact</link:label>
    <link:label id="lab_us-gaap_DefinedBenefitPlanPlanAssetsForeignCurrencyTranslationGainLoss_26FE67C65E8A9C3DBB2406E20DACACFA_label_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanPlanAssetsForeignCurrencyTranslationGainLoss_26FE67C65E8A9C3DBB2406E20DACACFA" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Plan Assets, Foreign Currency Translation Gain (Loss)</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DefinedBenefitPlanPlanAssetsForeignCurrencyTranslationGainLoss" xlink:label="loc_us-gaap_DefinedBenefitPlanPlanAssetsForeignCurrencyTranslationGainLoss_26FE67C65E8A9C3DBB2406E20DACACFA" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanPlanAssetsForeignCurrencyTranslationGainLoss_26FE67C65E8A9C3DBB2406E20DACACFA" xlink:to="lab_us-gaap_DefinedBenefitPlanPlanAssetsForeignCurrencyTranslationGainLoss_26FE67C65E8A9C3DBB2406E20DACACFA" xlink:type="arc" />
    <link:label id="lab_us-gaap_DefinedBenefitPlanFairValueOfPlanAssets_7E191BC382D9C9300E1106E20DAC2D8D_periodEndLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanFairValueOfPlanAssets_7E191BC382D9C9300E1106E20DAC2D8D" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel" xlink:type="resource" xml:lang="en-US">Fair value of plan assets at end of year</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DefinedBenefitPlanFairValueOfPlanAssets" xlink:label="loc_us-gaap_DefinedBenefitPlanFairValueOfPlanAssets_7E191BC382D9C9300E1106E20DAC2D8D" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanFairValueOfPlanAssets_7E191BC382D9C9300E1106E20DAC2D8D" xlink:to="lab_us-gaap_DefinedBenefitPlanFairValueOfPlanAssets_7E191BC382D9C9300E1106E20DAC2D8D" xlink:type="arc" />
    <link:label id="lab_us-gaap_DefinedBenefitPlanFundedStatusOfPlanAbstract_54AB17092106C176EC3406E20DAD3B80_terseLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanFundedStatusOfPlanAbstract_54AB17092106C176EC3406E20DAD3B80" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Funded (Unfunded) Status of Plan [Abstract]</link:label>
    <link:label id="lab_us-gaap_DefinedBenefitPlanFundedStatusOfPlanAbstract_54AB17092106C176EC3406E20DAD3B80_label_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanFundedStatusOfPlanAbstract_54AB17092106C176EC3406E20DAD3B80" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Funded (Unfunded) Status of Plan [Abstract]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DefinedBenefitPlanFundedStatusOfPlanAbstract" xlink:label="loc_us-gaap_DefinedBenefitPlanFundedStatusOfPlanAbstract_54AB17092106C176EC3406E20DAD3B80" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanFundedStatusOfPlanAbstract_54AB17092106C176EC3406E20DAD3B80" xlink:to="lab_us-gaap_DefinedBenefitPlanFundedStatusOfPlanAbstract_54AB17092106C176EC3406E20DAD3B80" xlink:type="arc" />
    <link:label id="lab_arnc_DefinedBenefitPlanNetFundedStatus_BCB43C9907E693FA6A7E06E20DAD7A69_totalLabel_en-US" xlink:label="lab_arnc_DefinedBenefitPlanNetFundedStatus_BCB43C9907E693FA6A7E06E20DAD7A69" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Net funded status</link:label>
    <link:label id="lab_arnc_DefinedBenefitPlanNetFundedStatus_BCB43C9907E693FA6A7E06E20DAD7A69_label_en-US" xlink:label="lab_arnc_DefinedBenefitPlanNetFundedStatus_BCB43C9907E693FA6A7E06E20DAD7A69" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan Net Funded Status</link:label>
    <link:label id="lab_arnc_DefinedBenefitPlanNetFundedStatus_BCB43C9907E693FA6A7E06E20DAD7A69_documentation_en-US" xlink:label="lab_arnc_DefinedBenefitPlanNetFundedStatus_BCB43C9907E693FA6A7E06E20DAD7A69" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Defined benefit plan net funded status.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_DefinedBenefitPlanNetFundedStatus" xlink:label="loc_arnc_DefinedBenefitPlanNetFundedStatus_BCB43C9907E693FA6A7E06E20DAD7A69" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_DefinedBenefitPlanNetFundedStatus_BCB43C9907E693FA6A7E06E20DAD7A69" xlink:to="lab_arnc_DefinedBenefitPlanNetFundedStatus_BCB43C9907E693FA6A7E06E20DAD7A69" xlink:type="arc" />
    <link:label id="lab_us-gaap_DefinedBenefitPlanAmountsRecognizedInBalanceSheetAbstract_D1E57363F999270E5CAA06E20DAD7AB0_terseLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanAmountsRecognizedInBalanceSheetAbstract_D1E57363F999270E5CAA06E20DAD7AB0" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Amounts recognized in the Consolidated Balance Sheet consist of:</link:label>
    <link:label id="lab_us-gaap_DefinedBenefitPlanAmountsRecognizedInBalanceSheetAbstract_D1E57363F999270E5CAA06E20DAD7AB0_label_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanAmountsRecognizedInBalanceSheetAbstract_D1E57363F999270E5CAA06E20DAD7AB0" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Amounts for Asset (Liability) Recognized in Statement of Financial Position [Abstract]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DefinedBenefitPlanAmountsRecognizedInBalanceSheetAbstract" xlink:label="loc_us-gaap_DefinedBenefitPlanAmountsRecognizedInBalanceSheetAbstract_D1E57363F999270E5CAA06E20DAD7AB0" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanAmountsRecognizedInBalanceSheetAbstract_D1E57363F999270E5CAA06E20DAD7AB0" xlink:to="lab_us-gaap_DefinedBenefitPlanAmountsRecognizedInBalanceSheetAbstract_D1E57363F999270E5CAA06E20DAD7AB0" xlink:type="arc" />
    <link:label id="lab_us-gaap_DefinedBenefitPlanAssetsForPlanBenefitsNoncurrent_41007C2E2C4F9DDA68D706E20DAD13C1_terseLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanAssetsForPlanBenefitsNoncurrent_41007C2E2C4F9DDA68D706E20DAD13C1" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Noncurrent assets</link:label>
    <link:label id="lab_us-gaap_DefinedBenefitPlanAssetsForPlanBenefitsNoncurrent_41007C2E2C4F9DDA68D706E20DAD13C1_label_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanAssetsForPlanBenefitsNoncurrent_41007C2E2C4F9DDA68D706E20DAD13C1" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Assets for Plan Benefits, Defined Benefit Plan</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DefinedBenefitPlanAssetsForPlanBenefitsNoncurrent" xlink:label="loc_us-gaap_DefinedBenefitPlanAssetsForPlanBenefitsNoncurrent_41007C2E2C4F9DDA68D706E20DAD13C1" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanAssetsForPlanBenefitsNoncurrent_41007C2E2C4F9DDA68D706E20DAD13C1" xlink:to="lab_us-gaap_DefinedBenefitPlanAssetsForPlanBenefitsNoncurrent_41007C2E2C4F9DDA68D706E20DAD13C1" xlink:type="arc" />
    <link:label id="lab_us-gaap_PensionAndOtherPostretirementDefinedBenefitPlansCurrentLiabilities_59BCD0DB05EE01E04D2B06E20DAD2594_negatedLabel_en-US" xlink:label="lab_us-gaap_PensionAndOtherPostretirementDefinedBenefitPlansCurrentLiabilities_59BCD0DB05EE01E04D2B06E20DAD2594" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xml:lang="en-US">Current liabilities</link:label>
    <link:label id="lab_us-gaap_PensionAndOtherPostretirementDefinedBenefitPlansCurrentLiabilities_59BCD0DB05EE01E04D2B06E20DAD2594_label_en-US" xlink:label="lab_us-gaap_PensionAndOtherPostretirementDefinedBenefitPlansCurrentLiabilities_59BCD0DB05EE01E04D2B06E20DAD2594" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Liability, Defined Benefit Plan, Current</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PensionAndOtherPostretirementDefinedBenefitPlansCurrentLiabilities" xlink:label="loc_us-gaap_PensionAndOtherPostretirementDefinedBenefitPlansCurrentLiabilities_59BCD0DB05EE01E04D2B06E20DAD2594" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PensionAndOtherPostretirementDefinedBenefitPlansCurrentLiabilities_59BCD0DB05EE01E04D2B06E20DAD2594" xlink:to="lab_us-gaap_PensionAndOtherPostretirementDefinedBenefitPlansCurrentLiabilities_59BCD0DB05EE01E04D2B06E20DAD2594" xlink:type="arc" />
    <link:label id="lab_us-gaap_PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent_808402761A3FC338FF1B06E20DAD2981_negatedLabel_en-US" xlink:label="lab_us-gaap_PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent_808402761A3FC338FF1B06E20DAD2981" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xml:lang="en-US">Noncurrent liabilities</link:label>
    <link:label id="lab_us-gaap_PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent_808402761A3FC338FF1B06E20DAD2981_label_en-US" xlink:label="lab_us-gaap_PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent_808402761A3FC338FF1B06E20DAD2981" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Liability, Defined Benefit Plan, Noncurrent</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent" xlink:label="loc_us-gaap_PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent_808402761A3FC338FF1B06E20DAD2981" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent_808402761A3FC338FF1B06E20DAD2981" xlink:to="lab_us-gaap_PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent_808402761A3FC338FF1B06E20DAD2981" xlink:type="arc" />
    <link:label id="lab_us-gaap_DefinedBenefitPlanAmountsRecognizedInBalanceSheet_3FFE7025E6A9B6F13EFA06E20DAEFB25_totalLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanAmountsRecognizedInBalanceSheet_3FFE7025E6A9B6F13EFA06E20DAEFB25" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Net amount recognized</link:label>
    <link:label id="lab_us-gaap_DefinedBenefitPlanAmountsRecognizedInBalanceSheet_3FFE7025E6A9B6F13EFA06E20DAEFB25_label_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanAmountsRecognizedInBalanceSheet_3FFE7025E6A9B6F13EFA06E20DAEFB25" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Amounts for Asset (Liability) Recognized in Statement of Financial Position</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DefinedBenefitPlanAmountsRecognizedInBalanceSheet" xlink:label="loc_us-gaap_DefinedBenefitPlanAmountsRecognizedInBalanceSheet_3FFE7025E6A9B6F13EFA06E20DAEFB25" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanAmountsRecognizedInBalanceSheet_3FFE7025E6A9B6F13EFA06E20DAEFB25" xlink:to="lab_us-gaap_DefinedBenefitPlanAmountsRecognizedInBalanceSheet_3FFE7025E6A9B6F13EFA06E20DAEFB25" xlink:type="arc" />
    <link:label id="lab_us-gaap_DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeBeforeTaxAbstract_455DDC57FFDABED0813406E20DAEEE5F_terseLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeBeforeTaxAbstract_455DDC57FFDABED0813406E20DAEEE5F" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Amounts recognized in Accumulated Other Comprehensive Loss consist of:</link:label>
    <link:label id="lab_us-gaap_DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeBeforeTaxAbstract_455DDC57FFDABED0813406E20DAEEE5F_label_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeBeforeTaxAbstract_455DDC57FFDABED0813406E20DAEEE5F" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Accumulated Other Comprehensive (Income) Loss, before Tax [Abstract]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeBeforeTaxAbstract" xlink:label="loc_us-gaap_DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeBeforeTaxAbstract_455DDC57FFDABED0813406E20DAEEE5F" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeBeforeTaxAbstract_455DDC57FFDABED0813406E20DAEEE5F" xlink:to="lab_us-gaap_DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeBeforeTaxAbstract_455DDC57FFDABED0813406E20DAEEE5F" xlink:type="arc" />
    <link:label id="lab_us-gaap_DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeNetGainsLossesBeforeTax_70DFDAEBBA0C1517EED206E20DAEE0F4_negatedLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeNetGainsLossesBeforeTax_70DFDAEBBA0C1517EED206E20DAEE0F4" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xml:lang="en-US">Net actuarial loss</link:label>
    <link:label id="lab_us-gaap_DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeNetGainsLossesBeforeTax_70DFDAEBBA0C1517EED206E20DAEE0F4_label_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeNetGainsLossesBeforeTax_70DFDAEBBA0C1517EED206E20DAEE0F4" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Accumulated Other Comprehensive Income (Loss), Gain (Loss), before Tax</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeNetGainsLossesBeforeTax" xlink:label="loc_us-gaap_DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeNetGainsLossesBeforeTax_70DFDAEBBA0C1517EED206E20DAEE0F4" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeNetGainsLossesBeforeTax_70DFDAEBBA0C1517EED206E20DAEE0F4" xlink:to="lab_us-gaap_DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeNetGainsLossesBeforeTax_70DFDAEBBA0C1517EED206E20DAEE0F4" xlink:type="arc" />
    <link:label id="lab_us-gaap_DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeNetPriorServiceCostCreditBeforeTax_F7506A9DD3209DC0EA1106E20DAEA8F4_terseLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeNetPriorServiceCostCreditBeforeTax_F7506A9DD3209DC0EA1106E20DAEA8F4" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Prior service cost (benefit)</link:label>
    <link:label id="lab_us-gaap_DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeNetPriorServiceCostCreditBeforeTax_F7506A9DD3209DC0EA1106E20DAEA8F4_label_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeNetPriorServiceCostCreditBeforeTax_F7506A9DD3209DC0EA1106E20DAEA8F4" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Accumulated Other Comprehensive (Income) Loss, Prior Service Cost (Credit), before Tax</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeNetPriorServiceCostCreditBeforeTax" xlink:label="loc_us-gaap_DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeNetPriorServiceCostCreditBeforeTax_F7506A9DD3209DC0EA1106E20DAEA8F4" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeNetPriorServiceCostCreditBeforeTax_F7506A9DD3209DC0EA1106E20DAEA8F4" xlink:to="lab_us-gaap_DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeNetPriorServiceCostCreditBeforeTax_F7506A9DD3209DC0EA1106E20DAEA8F4" xlink:type="arc" />
    <link:label id="lab_arnc_DefinedBenefitPlanNetAmountRecognizedBeforeTaxEffect_1A004FA6767AB03EB2A206E20DAE3B7A_totalLabel_en-US" xlink:label="lab_arnc_DefinedBenefitPlanNetAmountRecognizedBeforeTaxEffect_1A004FA6767AB03EB2A206E20DAE3B7A" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Net amount recognized, before tax effect</link:label>
    <link:label id="lab_arnc_DefinedBenefitPlanNetAmountRecognizedBeforeTaxEffect_1A004FA6767AB03EB2A206E20DAE3B7A_label_en-US" xlink:label="lab_arnc_DefinedBenefitPlanNetAmountRecognizedBeforeTaxEffect_1A004FA6767AB03EB2A206E20DAE3B7A" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan Net Amount Recognized Before Tax Effect</link:label>
    <link:label id="lab_arnc_DefinedBenefitPlanNetAmountRecognizedBeforeTaxEffect_1A004FA6767AB03EB2A206E20DAE3B7A_documentation_en-US" xlink:label="lab_arnc_DefinedBenefitPlanNetAmountRecognizedBeforeTaxEffect_1A004FA6767AB03EB2A206E20DAE3B7A" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan Net Amount Recognized Before Tax Effect</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_DefinedBenefitPlanNetAmountRecognizedBeforeTaxEffect" xlink:label="loc_arnc_DefinedBenefitPlanNetAmountRecognizedBeforeTaxEffect_1A004FA6767AB03EB2A206E20DAE3B7A" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_DefinedBenefitPlanNetAmountRecognizedBeforeTaxEffect_1A004FA6767AB03EB2A206E20DAE3B7A" xlink:to="lab_arnc_DefinedBenefitPlanNetAmountRecognizedBeforeTaxEffect_1A004FA6767AB03EB2A206E20DAE3B7A" xlink:type="arc" />
    <link:label id="lab_us-gaap_DefinedBenefitPlanAmountsRecognizedInOtherComprehensiveIncomeAbstract_8764A67F08246155CE4E06E20DAFAAE7_terseLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanAmountsRecognizedInOtherComprehensiveIncomeAbstract_8764A67F08246155CE4E06E20DAFAAE7" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Other changes in plan assets and benefit obligations recognized in Other Comprehensive Loss consist of:</link:label>
    <link:label id="lab_us-gaap_DefinedBenefitPlanAmountsRecognizedInOtherComprehensiveIncomeAbstract_8764A67F08246155CE4E06E20DAFAAE7_label_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanAmountsRecognizedInOtherComprehensiveIncomeAbstract_8764A67F08246155CE4E06E20DAFAAE7" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Amounts Recognized in Other Comprehensive Income (Loss) [Abstract]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DefinedBenefitPlanAmountsRecognizedInOtherComprehensiveIncomeAbstract" xlink:label="loc_us-gaap_DefinedBenefitPlanAmountsRecognizedInOtherComprehensiveIncomeAbstract_8764A67F08246155CE4E06E20DAFAAE7" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanAmountsRecognizedInOtherComprehensiveIncomeAbstract_8764A67F08246155CE4E06E20DAFAAE7" xlink:to="lab_us-gaap_DefinedBenefitPlanAmountsRecognizedInOtherComprehensiveIncomeAbstract_8764A67F08246155CE4E06E20DAFAAE7" xlink:type="arc" />
    <link:label id="lab_us-gaap_OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansNetUnamortizedGainLossArisingDuringPeriodBeforeTax_1A577E35651D96E4E80606E20DAF7174_negatedTerseLabel_en-US" xlink:label="lab_us-gaap_OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansNetUnamortizedGainLossArisingDuringPeriodBeforeTax_1A577E35651D96E4E80606E20DAF7174" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:type="resource" xml:lang="en-US">Net actuarial (gain) loss</link:label>
    <link:label id="lab_us-gaap_OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansNetUnamortizedGainLossArisingDuringPeriodBeforeTax_1A577E35651D96E4E80606E20DAF7174_label_en-US" xlink:label="lab_us-gaap_OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansNetUnamortizedGainLossArisingDuringPeriodBeforeTax_1A577E35651D96E4E80606E20DAF7174" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Other Comprehensive Income (Loss), Defined Benefit Plan, Gain (Loss) Arising During Period, before Tax</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansNetUnamortizedGainLossArisingDuringPeriodBeforeTax" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansNetUnamortizedGainLossArisingDuringPeriodBeforeTax_1A577E35651D96E4E80606E20DAF7174" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansNetUnamortizedGainLossArisingDuringPeriodBeforeTax_1A577E35651D96E4E80606E20DAF7174" xlink:to="lab_us-gaap_OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansNetUnamortizedGainLossArisingDuringPeriodBeforeTax_1A577E35651D96E4E80606E20DAF7174" xlink:type="arc" />
    <link:label id="lab_us-gaap_OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetGainLossBeforeTax_F4BFF90B6136DA0B0DEC06E20DAF0760_terseLabel_en-US" xlink:label="lab_us-gaap_OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetGainLossBeforeTax_F4BFF90B6136DA0B0DEC06E20DAF0760" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Amortization of accumulated net actuarial loss</link:label>
    <link:label id="lab_us-gaap_OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetGainLossBeforeTax_F4BFF90B6136DA0B0DEC06E20DAF0760_label_en-US" xlink:label="lab_us-gaap_OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetGainLossBeforeTax_F4BFF90B6136DA0B0DEC06E20DAF0760" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Other Comprehensive Income (Loss), Defined Benefit Plan, Gain (Loss), Reclassification Adjustment from AOCI, before Tax</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetGainLossBeforeTax" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetGainLossBeforeTax_F4BFF90B6136DA0B0DEC06E20DAF0760" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetGainLossBeforeTax_F4BFF90B6136DA0B0DEC06E20DAF0760" xlink:to="lab_us-gaap_OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetGainLossBeforeTax_F4BFF90B6136DA0B0DEC06E20DAF0760" xlink:type="arc" />
    <link:label id="lab_us-gaap_OtherComprehensiveIncomeDefinedBenefitPlanNetPriorServiceCostCreditArisingDuringPeriodBeforeTax_331C5B4F04825849A49C06E20DAF3495_terseLabel_en-US" xlink:label="lab_us-gaap_OtherComprehensiveIncomeDefinedBenefitPlanNetPriorServiceCostCreditArisingDuringPeriodBeforeTax_331C5B4F04825849A49C06E20DAF3495" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Prior service cost (benefit)</link:label>
    <link:label id="lab_us-gaap_OtherComprehensiveIncomeDefinedBenefitPlanNetPriorServiceCostCreditArisingDuringPeriodBeforeTax_331C5B4F04825849A49C06E20DAF3495_label_en-US" xlink:label="lab_us-gaap_OtherComprehensiveIncomeDefinedBenefitPlanNetPriorServiceCostCreditArisingDuringPeriodBeforeTax_331C5B4F04825849A49C06E20DAF3495" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Other Comprehensive (Income) Loss, Defined Benefit Plan, Prior Service Cost (Credit), before Tax</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_OtherComprehensiveIncomeDefinedBenefitPlanNetPriorServiceCostCreditArisingDuringPeriodBeforeTax" xlink:label="loc_us-gaap_OtherComprehensiveIncomeDefinedBenefitPlanNetPriorServiceCostCreditArisingDuringPeriodBeforeTax_331C5B4F04825849A49C06E20DAF3495" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OtherComprehensiveIncomeDefinedBenefitPlanNetPriorServiceCostCreditArisingDuringPeriodBeforeTax_331C5B4F04825849A49C06E20DAF3495" xlink:to="lab_us-gaap_OtherComprehensiveIncomeDefinedBenefitPlanNetPriorServiceCostCreditArisingDuringPeriodBeforeTax_331C5B4F04825849A49C06E20DAF3495" xlink:type="arc" />
    <link:label id="lab_us-gaap_OtherComprehensiveIncomeLossAmortizationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetPriorServiceCostCreditBeforeTax_8194B727D74EAA39E28E06E20DB0DABC_negatedLabel_en-US" xlink:label="lab_us-gaap_OtherComprehensiveIncomeLossAmortizationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetPriorServiceCostCreditBeforeTax_8194B727D74EAA39E28E06E20DB0DABC" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xml:lang="en-US">Amortization of prior service (cost) benefit</link:label>
    <link:label id="lab_us-gaap_OtherComprehensiveIncomeLossAmortizationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetPriorServiceCostCreditBeforeTax_8194B727D74EAA39E28E06E20DB0DABC_label_en-US" xlink:label="lab_us-gaap_OtherComprehensiveIncomeLossAmortizationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetPriorServiceCostCreditBeforeTax_8194B727D74EAA39E28E06E20DB0DABC" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Other Comprehensive (Income) Loss, Defined Benefit Plan, Prior Service Cost (Credit), Reclassification Adjustment from AOCI, before Tax</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_OtherComprehensiveIncomeLossAmortizationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetPriorServiceCostCreditBeforeTax" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossAmortizationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetPriorServiceCostCreditBeforeTax_8194B727D74EAA39E28E06E20DB0DABC" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OtherComprehensiveIncomeLossAmortizationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetPriorServiceCostCreditBeforeTax_8194B727D74EAA39E28E06E20DB0DABC" xlink:to="lab_us-gaap_OtherComprehensiveIncomeLossAmortizationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetPriorServiceCostCreditBeforeTax_8194B727D74EAA39E28E06E20DB0DABC" xlink:type="arc" />
    <link:label id="lab_arnc_OtherComprehensiveIncomeDefinedBenefitPlanNetAmountRecognizedBeforeTaxEffect_6B7A3CBF8839C2707A5706E20DB0DF00_totalLabel_en-US" xlink:label="lab_arnc_OtherComprehensiveIncomeDefinedBenefitPlanNetAmountRecognizedBeforeTaxEffect_6B7A3CBF8839C2707A5706E20DB0DF00" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Net amount recognized, before tax effect</link:label>
    <link:label id="lab_arnc_OtherComprehensiveIncomeDefinedBenefitPlanNetAmountRecognizedBeforeTaxEffect_6B7A3CBF8839C2707A5706E20DB0DF00_label_en-US" xlink:label="lab_arnc_OtherComprehensiveIncomeDefinedBenefitPlanNetAmountRecognizedBeforeTaxEffect_6B7A3CBF8839C2707A5706E20DB0DF00" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Other Comprehensive Income Defined Benefit Plan Net Amount Recognized Before Tax Effect</link:label>
    <link:label id="lab_arnc_OtherComprehensiveIncomeDefinedBenefitPlanNetAmountRecognizedBeforeTaxEffect_6B7A3CBF8839C2707A5706E20DB0DF00_documentation_en-US" xlink:label="lab_arnc_OtherComprehensiveIncomeDefinedBenefitPlanNetAmountRecognizedBeforeTaxEffect_6B7A3CBF8839C2707A5706E20DB0DF00" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Other comprehensive income defined benefit plan net amount recognized before tax effect.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_OtherComprehensiveIncomeDefinedBenefitPlanNetAmountRecognizedBeforeTaxEffect" xlink:label="loc_arnc_OtherComprehensiveIncomeDefinedBenefitPlanNetAmountRecognizedBeforeTaxEffect_6B7A3CBF8839C2707A5706E20DB0DF00" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_OtherComprehensiveIncomeDefinedBenefitPlanNetAmountRecognizedBeforeTaxEffect_6B7A3CBF8839C2707A5706E20DB0DF00" xlink:to="lab_arnc_OtherComprehensiveIncomeDefinedBenefitPlanNetAmountRecognizedBeforeTaxEffect_6B7A3CBF8839C2707A5706E20DB0DF00" xlink:type="arc" />
    <link:label id="lab_us-gaap_DefinedBenefitPlanFundedStatusOfPlan_9305E4F6753F79E817FF06E20DB0F6B1_terseLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanFundedStatusOfPlan_9305E4F6753F79E817FF06E20DB0F6B1" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Funded status for U.S. pension plans</link:label>
    <link:label id="lab_us-gaap_DefinedBenefitPlanFundedStatusOfPlan_9305E4F6753F79E817FF06E20DB0F6B1_label_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanFundedStatusOfPlan_9305E4F6753F79E817FF06E20DB0F6B1" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Funded (Unfunded) Status of Plan</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DefinedBenefitPlanFundedStatusOfPlan" xlink:label="loc_us-gaap_DefinedBenefitPlanFundedStatusOfPlan_9305E4F6753F79E817FF06E20DB0F6B1" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanFundedStatusOfPlan_9305E4F6753F79E817FF06E20DB0F6B1" xlink:to="lab_us-gaap_DefinedBenefitPlanFundedStatusOfPlan_9305E4F6753F79E817FF06E20DB0F6B1" xlink:type="arc" />
    <link:label id="lab_us-gaap_BusinessCombinationsAbstract_0C7B4D0E249D9B2D468C0735D4AD65D9_label_en-US" xlink:label="lab_us-gaap_BusinessCombinationsAbstract_0C7B4D0E249D9B2D468C0735D4AD65D9" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Business Combinations [Abstract]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_BusinessCombinationsAbstract" xlink:label="loc_us-gaap_BusinessCombinationsAbstract_0C7B4D0E249D9B2D468C0735D4AD65D9" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_BusinessCombinationsAbstract_0C7B4D0E249D9B2D468C0735D4AD65D9" xlink:to="lab_us-gaap_BusinessCombinationsAbstract_0C7B4D0E249D9B2D468C0735D4AD65D9" xlink:type="arc" />
    <link:label id="lab_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_0CF186A16230324AF9310735D4AD5965_terseLabel_en-US" xlink:label="lab_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_0CF186A16230324AF9310735D4AD5965" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Schedule of Business Acquisitions, by Acquisition [Table]</link:label>
    <link:label id="lab_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_0CF186A16230324AF9310735D4AD5965_label_en-US" xlink:label="lab_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_0CF186A16230324AF9310735D4AD5965" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Schedule of Business Acquisitions, by Acquisition [Table]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable" xlink:label="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_0CF186A16230324AF9310735D4AD5965" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_0CF186A16230324AF9310735D4AD5965" xlink:to="lab_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_0CF186A16230324AF9310735D4AD5965" xlink:type="arc" />
    <link:label id="lab_dei_LegalEntityAxis_6102F5165AA522BD45B50735D4ADFEF0_terseLabel_en-US" xlink:label="lab_dei_LegalEntityAxis_6102F5165AA522BD45B50735D4ADFEF0" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Legal Entity [Axis]</link:label>
    <link:label id="lab_dei_LegalEntityAxis_6102F5165AA522BD45B50735D4ADFEF0_label_en-US" xlink:label="lab_dei_LegalEntityAxis_6102F5165AA522BD45B50735D4ADFEF0" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Legal Entity [Axis]</link:label>
    <link:loc xlink:href="https://xbrl.sec.gov/dei/2018/dei-2018-01-31.xsd#dei_LegalEntityAxis" xlink:label="loc_dei_LegalEntityAxis_6102F5165AA522BD45B50735D4ADFEF0" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_dei_LegalEntityAxis_6102F5165AA522BD45B50735D4ADFEF0" xlink:to="lab_dei_LegalEntityAxis_6102F5165AA522BD45B50735D4ADFEF0" xlink:type="arc" />
    <link:label id="lab_dei_EntityDomain_0FC89AA3E4448B78E5EF0735D4ADE7FC_terseLabel_en-US" xlink:label="lab_dei_EntityDomain_0FC89AA3E4448B78E5EF0735D4ADE7FC" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Entity [Domain]</link:label>
    <link:label id="lab_dei_EntityDomain_0FC89AA3E4448B78E5EF0735D4ADE7FC_label_en-US" xlink:label="lab_dei_EntityDomain_0FC89AA3E4448B78E5EF0735D4ADE7FC" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Entity [Domain]</link:label>
    <link:loc xlink:href="https://xbrl.sec.gov/dei/2018/dei-2018-01-31.xsd#dei_EntityDomain" xlink:label="loc_dei_EntityDomain_0FC89AA3E4448B78E5EF0735D4ADE7FC" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_dei_EntityDomain_0FC89AA3E4448B78E5EF0735D4ADE7FC" xlink:to="lab_dei_EntityDomain_0FC89AA3E4448B78E5EF0735D4ADE7FC" xlink:type="arc" />
    <link:label id="lab_arnc_TaChenInternationalInc.Member_CE996E59F1EFC9F432D90735D4ADB79E_terseLabel_en-US" xlink:label="lab_arnc_TaChenInternationalInc.Member_CE996E59F1EFC9F432D90735D4ADB79E" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Ta Chen International, Inc.</link:label>
    <link:label id="lab_arnc_TaChenInternationalInc.Member_CE996E59F1EFC9F432D90735D4ADB79E_label_en-US" xlink:label="lab_arnc_TaChenInternationalInc.Member_CE996E59F1EFC9F432D90735D4ADB79E" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Ta Chen International, Inc. [Member]</link:label>
    <link:label id="lab_arnc_TaChenInternationalInc.Member_CE996E59F1EFC9F432D90735D4ADB79E_documentation_en-US" xlink:label="lab_arnc_TaChenInternationalInc.Member_CE996E59F1EFC9F432D90735D4ADB79E" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Ta Chen International, Inc. [Member]</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_TaChenInternationalInc.Member" xlink:label="loc_arnc_TaChenInternationalInc.Member_CE996E59F1EFC9F432D90735D4ADB79E" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_TaChenInternationalInc.Member_CE996E59F1EFC9F432D90735D4ADB79E" xlink:to="lab_arnc_TaChenInternationalInc.Member_CE996E59F1EFC9F432D90735D4ADB79E" xlink:type="arc" />
    <link:label id="lab_us-gaap_StatementBusinessSegmentsAxis_865A6176FB08875A6B670735D4ADC067_terseLabel_en-US" xlink:label="lab_us-gaap_StatementBusinessSegmentsAxis_865A6176FB08875A6B670735D4ADC067" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Segments [Axis]</link:label>
    <link:label id="lab_us-gaap_StatementBusinessSegmentsAxis_865A6176FB08875A6B670735D4ADC067_label_en-US" xlink:label="lab_us-gaap_StatementBusinessSegmentsAxis_865A6176FB08875A6B670735D4ADC067" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Segments [Axis]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_StatementBusinessSegmentsAxis" xlink:label="loc_us-gaap_StatementBusinessSegmentsAxis_865A6176FB08875A6B670735D4ADC067" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_865A6176FB08875A6B670735D4ADC067" xlink:to="lab_us-gaap_StatementBusinessSegmentsAxis_865A6176FB08875A6B670735D4ADC067" xlink:type="arc" />
    <link:label id="lab_us-gaap_SegmentDomain_4EDD459DA9ADDE74990A0735D4AD3134_terseLabel_en-US" xlink:label="lab_us-gaap_SegmentDomain_4EDD459DA9ADDE74990A0735D4AD3134" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Segments [Domain]</link:label>
    <link:label id="lab_us-gaap_SegmentDomain_4EDD459DA9ADDE74990A0735D4AD3134_label_en-US" xlink:label="lab_us-gaap_SegmentDomain_4EDD459DA9ADDE74990A0735D4AD3134" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Segments [Domain]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_SegmentDomain" xlink:label="loc_us-gaap_SegmentDomain_4EDD459DA9ADDE74990A0735D4AD3134" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SegmentDomain_4EDD459DA9ADDE74990A0735D4AD3134" xlink:to="lab_us-gaap_SegmentDomain_4EDD459DA9ADDE74990A0735D4AD3134" xlink:type="arc" />
    <link:label id="lab_arnc_TransportationAndConstructionSolutionsMember_AE32EDB4A37199999E3A0735D4ADE40E_terseLabel_en-US" xlink:label="lab_arnc_TransportationAndConstructionSolutionsMember_AE32EDB4A37199999E3A0735D4ADE40E" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Transportation and Construction Solutions</link:label>
    <link:label id="lab_arnc_TransportationAndConstructionSolutionsMember_AE32EDB4A37199999E3A0735D4ADE40E_label_en-US" xlink:label="lab_arnc_TransportationAndConstructionSolutionsMember_AE32EDB4A37199999E3A0735D4ADE40E" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Transportation And Construction Solutions [Member]</link:label>
    <link:label id="lab_arnc_TransportationAndConstructionSolutionsMember_AE32EDB4A37199999E3A0735D4ADE40E_documentation_en-US" xlink:label="lab_arnc_TransportationAndConstructionSolutionsMember_AE32EDB4A37199999E3A0735D4ADE40E" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Transportation and construction solutions.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_TransportationAndConstructionSolutionsMember" xlink:label="loc_arnc_TransportationAndConstructionSolutionsMember_AE32EDB4A37199999E3A0735D4ADE40E" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_TransportationAndConstructionSolutionsMember_AE32EDB4A37199999E3A0735D4ADE40E" xlink:to="lab_arnc_TransportationAndConstructionSolutionsMember_AE32EDB4A37199999E3A0735D4ADE40E" xlink:type="arc" />
    <link:label id="lab_arnc_BuildingandConstructionSystemsMember_888C776706780551F5200735D4ADDE75_terseLabel_en-US" xlink:label="lab_arnc_BuildingandConstructionSystemsMember_888C776706780551F5200735D4ADDE75" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Building and Construction Systems</link:label>
    <link:label id="lab_arnc_BuildingandConstructionSystemsMember_888C776706780551F5200735D4ADDE75_label_en-US" xlink:label="lab_arnc_BuildingandConstructionSystemsMember_888C776706780551F5200735D4ADDE75" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Building and Construction Systems [Member]</link:label>
    <link:label id="lab_arnc_BuildingandConstructionSystemsMember_888C776706780551F5200735D4ADDE75_documentation_en-US" xlink:label="lab_arnc_BuildingandConstructionSystemsMember_888C776706780551F5200735D4ADDE75" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Building and Construction Systems [Member]</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_BuildingandConstructionSystemsMember" xlink:label="loc_arnc_BuildingandConstructionSystemsMember_888C776706780551F5200735D4ADDE75" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_BuildingandConstructionSystemsMember_888C776706780551F5200735D4ADDE75" xlink:to="lab_arnc_BuildingandConstructionSystemsMember_888C776706780551F5200735D4ADDE75" xlink:type="arc" />
    <link:label id="lab_arnc_EngineeredProductsAndSolutionsMember_CBC7D5F421320C1E8CDA0735D4AD0987_terseLabel_en-US" xlink:label="lab_arnc_EngineeredProductsAndSolutionsMember_CBC7D5F421320C1E8CDA0735D4AD0987" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Engineered Products and Solutions</link:label>
    <link:label id="lab_arnc_EngineeredProductsAndSolutionsMember_CBC7D5F421320C1E8CDA0735D4AD0987_label_en-US" xlink:label="lab_arnc_EngineeredProductsAndSolutionsMember_CBC7D5F421320C1E8CDA0735D4AD0987" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Engineered Products And Solutions [Member]</link:label>
    <link:label id="lab_arnc_EngineeredProductsAndSolutionsMember_CBC7D5F421320C1E8CDA0735D4AD0987_documentation_en-US" xlink:label="lab_arnc_EngineeredProductsAndSolutionsMember_CBC7D5F421320C1E8CDA0735D4AD0987" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Engineered products and solutions.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_EngineeredProductsAndSolutionsMember" xlink:label="loc_arnc_EngineeredProductsAndSolutionsMember_CBC7D5F421320C1E8CDA0735D4AD0987" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_EngineeredProductsAndSolutionsMember_CBC7D5F421320C1E8CDA0735D4AD0987" xlink:to="lab_arnc_EngineeredProductsAndSolutionsMember_CBC7D5F421320C1E8CDA0735D4AD0987" xlink:type="arc" />
    <link:label id="lab_arnc_ThirdPartySalesMember_303EAB37B3BA51C248D50735D4B1A0D8_terseLabel_en-US" xlink:label="lab_arnc_ThirdPartySalesMember_303EAB37B3BA51C248D50735D4B1A0D8" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Third-Party Sales</link:label>
    <link:label id="lab_arnc_ThirdPartySalesMember_303EAB37B3BA51C248D50735D4B1A0D8_label_en-US" xlink:label="lab_arnc_ThirdPartySalesMember_303EAB37B3BA51C248D50735D4B1A0D8" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Third Party Sales [Member]</link:label>
    <link:label id="lab_arnc_ThirdPartySalesMember_303EAB37B3BA51C248D50735D4B1A0D8_documentation_en-US" xlink:label="lab_arnc_ThirdPartySalesMember_303EAB37B3BA51C248D50735D4B1A0D8" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Third party sales.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_ThirdPartySalesMember" xlink:label="loc_arnc_ThirdPartySalesMember_303EAB37B3BA51C248D50735D4B1A0D8" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_ThirdPartySalesMember_303EAB37B3BA51C248D50735D4B1A0D8" xlink:to="lab_arnc_ThirdPartySalesMember_303EAB37B3BA51C248D50735D4B1A0D8" xlink:type="arc" />
    <link:label id="lab_us-gaap_RestructuringCostAndReserveAxis_C18AD58AA8E6C870A9EA0735D4B1A494_terseLabel_en-US" xlink:label="lab_us-gaap_RestructuringCostAndReserveAxis_C18AD58AA8E6C870A9EA0735D4B1A494" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Restructuring Type [Axis]</link:label>
    <link:label id="lab_us-gaap_RestructuringCostAndReserveAxis_C18AD58AA8E6C870A9EA0735D4B1A494_label_en-US" xlink:label="lab_us-gaap_RestructuringCostAndReserveAxis_C18AD58AA8E6C870A9EA0735D4B1A494" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Restructuring Type [Axis]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RestructuringCostAndReserveAxis" xlink:label="loc_us-gaap_RestructuringCostAndReserveAxis_C18AD58AA8E6C870A9EA0735D4B1A494" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RestructuringCostAndReserveAxis_C18AD58AA8E6C870A9EA0735D4B1A494" xlink:to="lab_us-gaap_RestructuringCostAndReserveAxis_C18AD58AA8E6C870A9EA0735D4B1A494" xlink:type="arc" />
    <link:label id="lab_us-gaap_TypeOfRestructuringDomain_8BA84AE363522C7719280735D4B1EBB9_terseLabel_en-US" xlink:label="lab_us-gaap_TypeOfRestructuringDomain_8BA84AE363522C7719280735D4B1EBB9" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Type of Restructuring [Domain]</link:label>
    <link:label id="lab_us-gaap_TypeOfRestructuringDomain_8BA84AE363522C7719280735D4B1EBB9_label_en-US" xlink:label="lab_us-gaap_TypeOfRestructuringDomain_8BA84AE363522C7719280735D4B1EBB9" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Type of Restructuring [Domain]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_TypeOfRestructuringDomain" xlink:label="loc_us-gaap_TypeOfRestructuringDomain_8BA84AE363522C7719280735D4B1EBB9" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_TypeOfRestructuringDomain_8BA84AE363522C7719280735D4B1EBB9" xlink:to="lab_us-gaap_TypeOfRestructuringDomain_8BA84AE363522C7719280735D4B1EBB9" xlink:type="arc" />
    <link:label id="lab_arnc_DivestedBusinessesMember_32D67D0D420DF53679FE0735D4B1494C_terseLabel_en-US" xlink:label="lab_arnc_DivestedBusinessesMember_32D67D0D420DF53679FE0735D4B1494C" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Divested Businesses</link:label>
    <link:label id="lab_arnc_DivestedBusinessesMember_32D67D0D420DF53679FE0735D4B1494C_label_en-US" xlink:label="lab_arnc_DivestedBusinessesMember_32D67D0D420DF53679FE0735D4B1494C" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Divested Businesses [Member]</link:label>
    <link:label id="lab_arnc_DivestedBusinessesMember_32D67D0D420DF53679FE0735D4B1494C_documentation_en-US" xlink:label="lab_arnc_DivestedBusinessesMember_32D67D0D420DF53679FE0735D4B1494C" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Divested businesses</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_DivestedBusinessesMember" xlink:label="loc_arnc_DivestedBusinessesMember_32D67D0D420DF53679FE0735D4B1494C" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_DivestedBusinessesMember_32D67D0D420DF53679FE0735D4B1494C" xlink:to="lab_arnc_DivestedBusinessesMember_32D67D0D420DF53679FE0735D4B1494C" xlink:type="arc" />
    <link:label id="lab_us-gaap_DisposalGroupClassificationAxis_7BF1F177D5BFA51507C20735D4B17F9B_terseLabel_en-US" xlink:label="lab_us-gaap_DisposalGroupClassificationAxis_7BF1F177D5BFA51507C20735D4B17F9B" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Disposal Group Classification [Axis]</link:label>
    <link:label id="lab_us-gaap_DisposalGroupClassificationAxis_7BF1F177D5BFA51507C20735D4B17F9B_label_en-US" xlink:label="lab_us-gaap_DisposalGroupClassificationAxis_7BF1F177D5BFA51507C20735D4B17F9B" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Disposal Group Classification [Axis]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DisposalGroupClassificationAxis" xlink:label="loc_us-gaap_DisposalGroupClassificationAxis_7BF1F177D5BFA51507C20735D4B17F9B" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DisposalGroupClassificationAxis_7BF1F177D5BFA51507C20735D4B17F9B" xlink:to="lab_us-gaap_DisposalGroupClassificationAxis_7BF1F177D5BFA51507C20735D4B17F9B" xlink:type="arc" />
    <link:label id="lab_us-gaap_DisposalGroupClassificationDomain_FAEA8088E9418BA355C70735D4B17836_terseLabel_en-US" xlink:label="lab_us-gaap_DisposalGroupClassificationDomain_FAEA8088E9418BA355C70735D4B17836" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Disposal Group Classification [Domain]</link:label>
    <link:label id="lab_us-gaap_DisposalGroupClassificationDomain_FAEA8088E9418BA355C70735D4B17836_label_en-US" xlink:label="lab_us-gaap_DisposalGroupClassificationDomain_FAEA8088E9418BA355C70735D4B17836" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Disposal Group Classification [Domain]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DisposalGroupClassificationDomain" xlink:label="loc_us-gaap_DisposalGroupClassificationDomain_FAEA8088E9418BA355C70735D4B17836" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DisposalGroupClassificationDomain_FAEA8088E9418BA355C70735D4B17836" xlink:to="lab_us-gaap_DisposalGroupClassificationDomain_FAEA8088E9418BA355C70735D4B17836" xlink:type="arc" />
    <link:label id="lab_us-gaap_DisposalGroupDisposedOfBySaleNotDiscontinuedOperationsMember_5589D9892566C1A517BE0735D4B1C9E3_terseLabel_en-US" xlink:label="lab_us-gaap_DisposalGroupDisposedOfBySaleNotDiscontinuedOperationsMember_5589D9892566C1A517BE0735D4B1C9E3" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Disposed of by Sale</link:label>
    <link:label id="lab_us-gaap_DisposalGroupDisposedOfBySaleNotDiscontinuedOperationsMember_5589D9892566C1A517BE0735D4B1C9E3_label_en-US" xlink:label="lab_us-gaap_DisposalGroupDisposedOfBySaleNotDiscontinuedOperationsMember_5589D9892566C1A517BE0735D4B1C9E3" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Disposal Group, Disposed of by Sale, Not Discontinued Operations [Member]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DisposalGroupDisposedOfBySaleNotDiscontinuedOperationsMember" xlink:label="loc_us-gaap_DisposalGroupDisposedOfBySaleNotDiscontinuedOperationsMember_5589D9892566C1A517BE0735D4B1C9E3" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DisposalGroupDisposedOfBySaleNotDiscontinuedOperationsMember_5589D9892566C1A517BE0735D4B1C9E3" xlink:to="lab_us-gaap_DisposalGroupDisposedOfBySaleNotDiscontinuedOperationsMember_5589D9892566C1A517BE0735D4B1C9E3" xlink:type="arc" />
    <link:label id="lab_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis_E809E0C1264CA54147AA0735D4B5DE17_terseLabel_en-US" xlink:label="lab_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis_E809E0C1264CA54147AA0735D4B5DE17" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Disposal Group Name [Axis]</link:label>
    <link:label id="lab_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis_E809E0C1264CA54147AA0735D4B5DE17_label_en-US" xlink:label="lab_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis_E809E0C1264CA54147AA0735D4B5DE17" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Disposal Group Name [Axis]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis" xlink:label="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis_E809E0C1264CA54147AA0735D4B5DE17" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis_E809E0C1264CA54147AA0735D4B5DE17" xlink:to="lab_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis_E809E0C1264CA54147AA0735D4B5DE17" xlink:type="arc" />
    <link:label id="lab_us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain_A38AAFCA046E452D696D0735D4B53217_terseLabel_en-US" xlink:label="lab_us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain_A38AAFCA046E452D696D0735D4B53217" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Disposal Group Name [Domain]</link:label>
    <link:label id="lab_us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain_A38AAFCA046E452D696D0735D4B53217_label_en-US" xlink:label="lab_us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain_A38AAFCA046E452D696D0735D4B53217" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Disposal Group Name [Domain]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain" xlink:label="loc_us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain_A38AAFCA046E452D696D0735D4B53217" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain_A38AAFCA046E452D696D0735D4B53217" xlink:to="lab_us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain_A38AAFCA046E452D696D0735D4B53217" xlink:type="arc" />
    <link:label id="lab_arnc_LatinAmericaExtrusionsLAEMember_3008FE6EA7D20C206F0D0735D4B51C12_terseLabel_en-US" xlink:label="lab_arnc_LatinAmericaExtrusionsLAEMember_3008FE6EA7D20C206F0D0735D4B51C12" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Latin America Extrusions (LAE)</link:label>
    <link:label id="lab_arnc_LatinAmericaExtrusionsLAEMember_3008FE6EA7D20C206F0D0735D4B51C12_label_en-US" xlink:label="lab_arnc_LatinAmericaExtrusionsLAEMember_3008FE6EA7D20C206F0D0735D4B51C12" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Latin America Extrusions (LAE) [Member]</link:label>
    <link:label id="lab_arnc_LatinAmericaExtrusionsLAEMember_3008FE6EA7D20C206F0D0735D4B51C12_documentation_en-US" xlink:label="lab_arnc_LatinAmericaExtrusionsLAEMember_3008FE6EA7D20C206F0D0735D4B51C12" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Latin America Extrusions (LAE) [Member]</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_LatinAmericaExtrusionsLAEMember" xlink:label="loc_arnc_LatinAmericaExtrusionsLAEMember_3008FE6EA7D20C206F0D0735D4B51C12" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_LatinAmericaExtrusionsLAEMember_3008FE6EA7D20C206F0D0735D4B51C12" xlink:to="lab_arnc_LatinAmericaExtrusionsLAEMember_3008FE6EA7D20C206F0D0735D4B51C12" xlink:type="arc" />
    <link:label id="lab_arnc_TexarkanaTexasRollingMillAndCastHouseMember_131E117462C9B11849070735D4B503A7_terseLabel_en-US" xlink:label="lab_arnc_TexarkanaTexasRollingMillAndCastHouseMember_131E117462C9B11849070735D4B503A7" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Texarkana, Texas Rolling Mill And Cast House</link:label>
    <link:label id="lab_arnc_TexarkanaTexasRollingMillAndCastHouseMember_131E117462C9B11849070735D4B503A7_label_en-US" xlink:label="lab_arnc_TexarkanaTexasRollingMillAndCastHouseMember_131E117462C9B11849070735D4B503A7" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Texarkana, Texas Rolling Mill And Cast House [Member]</link:label>
    <link:label id="lab_arnc_TexarkanaTexasRollingMillAndCastHouseMember_131E117462C9B11849070735D4B503A7_documentation_en-US" xlink:label="lab_arnc_TexarkanaTexasRollingMillAndCastHouseMember_131E117462C9B11849070735D4B503A7" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Texarkana, Texas Rolling Mill And Cast House [Member]</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_TexarkanaTexasRollingMillAndCastHouseMember" xlink:label="loc_arnc_TexarkanaTexasRollingMillAndCastHouseMember_131E117462C9B11849070735D4B503A7" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_TexarkanaTexasRollingMillAndCastHouseMember_131E117462C9B11849070735D4B503A7" xlink:to="lab_arnc_TexarkanaTexasRollingMillAndCastHouseMember_131E117462C9B11849070735D4B503A7" xlink:type="arc" />
    <link:label id="lab_arnc_EgerMember_5FBE9B39F2AF805C83C20735D4B9253F_terseLabel_en-US" xlink:label="lab_arnc_EgerMember_5FBE9B39F2AF805C83C20735D4B9253F" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Eger</link:label>
    <link:label id="lab_arnc_EgerMember_5FBE9B39F2AF805C83C20735D4B9253F_label_en-US" xlink:label="lab_arnc_EgerMember_5FBE9B39F2AF805C83C20735D4B9253F" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Eger [Member]</link:label>
    <link:label id="lab_arnc_EgerMember_5FBE9B39F2AF805C83C20735D4B9253F_documentation_en-US" xlink:label="lab_arnc_EgerMember_5FBE9B39F2AF805C83C20735D4B9253F" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Eger [Member]</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_EgerMember" xlink:label="loc_arnc_EgerMember_5FBE9B39F2AF805C83C20735D4B9253F" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_EgerMember_5FBE9B39F2AF805C83C20735D4B9253F" xlink:to="lab_arnc_EgerMember_5FBE9B39F2AF805C83C20735D4B9253F" xlink:type="arc" />
    <link:label id="lab_us-gaap_BusinessAcquisitionLineItems_3EA343294FB5BD2C3F900735D4B9682B_terseLabel_en-US" xlink:label="lab_us-gaap_BusinessAcquisitionLineItems_3EA343294FB5BD2C3F900735D4B9682B" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Business Acquisition [Line Items]</link:label>
    <link:label id="lab_us-gaap_BusinessAcquisitionLineItems_3EA343294FB5BD2C3F900735D4B9682B_label_en-US" xlink:label="lab_us-gaap_BusinessAcquisitionLineItems_3EA343294FB5BD2C3F900735D4B9682B" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Business Acquisition [Line Items]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_BusinessAcquisitionLineItems" xlink:label="loc_us-gaap_BusinessAcquisitionLineItems_3EA343294FB5BD2C3F900735D4B9682B" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_3EA343294FB5BD2C3F900735D4B9682B" xlink:to="lab_us-gaap_BusinessAcquisitionLineItems_3EA343294FB5BD2C3F900735D4B9682B" xlink:type="arc" />
    <link:label id="lab_us-gaap_ProceedsFromDivestitureOfBusinesses_FFAE667E19181791642F0735D4B94A77_terseLabel_en-US" xlink:label="lab_us-gaap_ProceedsFromDivestitureOfBusinesses_FFAE667E19181791642F0735D4B94A77" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Proceeds from divestiture of businesses</link:label>
    <link:label id="lab_us-gaap_ProceedsFromDivestitureOfBusinesses_FFAE667E19181791642F0735D4B94A77_label_en-US" xlink:label="lab_us-gaap_ProceedsFromDivestitureOfBusinesses_FFAE667E19181791642F0735D4B94A77" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Proceeds from Divestiture of Businesses</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ProceedsFromDivestitureOfBusinesses" xlink:label="loc_us-gaap_ProceedsFromDivestitureOfBusinesses_FFAE667E19181791642F0735D4B94A77" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ProceedsFromDivestitureOfBusinesses_FFAE667E19181791642F0735D4B94A77" xlink:to="lab_us-gaap_ProceedsFromDivestitureOfBusinesses_FFAE667E19181791642F0735D4B94A77" xlink:type="arc" />
    <link:label id="lab_us-gaap_RestructuringCharges_9CAE7473431A16638FB20735D4B945AD_verboseLabel_en-US" xlink:label="lab_us-gaap_RestructuringCharges_9CAE7473431A16638FB20735D4B945AD" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Restructuring and other charges</link:label>
    <link:label id="lab_us-gaap_RestructuringCharges_9CAE7473431A16638FB20735D4B945AD_label_en-US" xlink:label="lab_us-gaap_RestructuringCharges_9CAE7473431A16638FB20735D4B945AD" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Restructuring Charges</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RestructuringCharges" xlink:label="loc_us-gaap_RestructuringCharges_9CAE7473431A16638FB20735D4B945AD" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RestructuringCharges_9CAE7473431A16638FB20735D4B945AD" xlink:to="lab_us-gaap_RestructuringCharges_9CAE7473431A16638FB20735D4B945AD" xlink:type="arc" />
    <link:label id="lab_us-gaap_BusinessAcquisitionsPurchasePriceAllocationSubsequentYearsRemainingAdjustments_E723DED8040A429F359C0735D4B9B276_terseLabel_en-US" xlink:label="lab_us-gaap_BusinessAcquisitionsPurchasePriceAllocationSubsequentYearsRemainingAdjustments_E723DED8040A429F359C0735D4B9B276" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Balance sheet adjustment</link:label>
    <link:label id="lab_us-gaap_BusinessAcquisitionsPurchasePriceAllocationSubsequentYearsRemainingAdjustments_E723DED8040A429F359C0735D4B9B276_label_en-US" xlink:label="lab_us-gaap_BusinessAcquisitionsPurchasePriceAllocationSubsequentYearsRemainingAdjustments_E723DED8040A429F359C0735D4B9B276" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Business Acquisitions, Purchase Price Allocation, Subsequent Years, Remaining Adjustments</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_BusinessAcquisitionsPurchasePriceAllocationSubsequentYearsRemainingAdjustments" xlink:label="loc_us-gaap_BusinessAcquisitionsPurchasePriceAllocationSubsequentYearsRemainingAdjustments_E723DED8040A429F359C0735D4B9B276" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_BusinessAcquisitionsPurchasePriceAllocationSubsequentYearsRemainingAdjustments_E723DED8040A429F359C0735D4B9B276" xlink:to="lab_us-gaap_BusinessAcquisitionsPurchasePriceAllocationSubsequentYearsRemainingAdjustments_E723DED8040A429F359C0735D4B9B276" xlink:type="arc" />
    <link:label id="lab_us-gaap_DisposalGroupIncludingDiscontinuedOperationRevenue_29A52D148FCF79A780140735D4B9DBD3_verboseLabel_en-US" xlink:label="lab_us-gaap_DisposalGroupIncludingDiscontinuedOperationRevenue_29A52D148FCF79A780140735D4B9DBD3" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Sales</link:label>
    <link:label id="lab_us-gaap_DisposalGroupIncludingDiscontinuedOperationRevenue_29A52D148FCF79A780140735D4B9DBD3_label_en-US" xlink:label="lab_us-gaap_DisposalGroupIncludingDiscontinuedOperationRevenue_29A52D148FCF79A780140735D4B9DBD3" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Disposal Group, Including Discontinued Operation, Revenue</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DisposalGroupIncludingDiscontinuedOperationRevenue" xlink:label="loc_us-gaap_DisposalGroupIncludingDiscontinuedOperationRevenue_29A52D148FCF79A780140735D4B9DBD3" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DisposalGroupIncludingDiscontinuedOperationRevenue_29A52D148FCF79A780140735D4B9DBD3" xlink:to="lab_us-gaap_DisposalGroupIncludingDiscontinuedOperationRevenue_29A52D148FCF79A780140735D4B9DBD3" xlink:type="arc" />
    <link:label id="lab_arnc_NumberOfEmployees_4AB6C9E2F770C13D06090735D4B9BED5_terseLabel_en-US" xlink:label="lab_arnc_NumberOfEmployees_4AB6C9E2F770C13D06090735D4B9BED5" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Number of employees</link:label>
    <link:label id="lab_arnc_NumberOfEmployees_4AB6C9E2F770C13D06090735D4B9BED5_label_en-US" xlink:label="lab_arnc_NumberOfEmployees_4AB6C9E2F770C13D06090735D4B9BED5" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Number Of Employees</link:label>
    <link:label id="lab_arnc_NumberOfEmployees_4AB6C9E2F770C13D06090735D4B9BED5_documentation_en-US" xlink:label="lab_arnc_NumberOfEmployees_4AB6C9E2F770C13D06090735D4B9BED5" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Number of employees.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_NumberOfEmployees" xlink:label="loc_arnc_NumberOfEmployees_4AB6C9E2F770C13D06090735D4B9BED5" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_NumberOfEmployees_4AB6C9E2F770C13D06090735D4B9BED5" xlink:to="lab_arnc_NumberOfEmployees_4AB6C9E2F770C13D06090735D4B9BED5" xlink:type="arc" />
    <link:label id="lab_us-gaap_DisposalGroupIncludingDiscontinuedOperationConsideration_D2D40F108E9D54C4D30F0735D4B96210_terseLabel_en-US" xlink:label="lab_us-gaap_DisposalGroupIncludingDiscontinuedOperationConsideration_D2D40F108E9D54C4D30F0735D4B96210" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Consideration</link:label>
    <link:label id="lab_us-gaap_DisposalGroupIncludingDiscontinuedOperationConsideration_D2D40F108E9D54C4D30F0735D4B96210_label_en-US" xlink:label="lab_us-gaap_DisposalGroupIncludingDiscontinuedOperationConsideration_D2D40F108E9D54C4D30F0735D4B96210" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Disposal Group, Including Discontinued Operation, Consideration</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DisposalGroupIncludingDiscontinuedOperationConsideration" xlink:label="loc_us-gaap_DisposalGroupIncludingDiscontinuedOperationConsideration_D2D40F108E9D54C4D30F0735D4B96210" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DisposalGroupIncludingDiscontinuedOperationConsideration_D2D40F108E9D54C4D30F0735D4B96210" xlink:to="lab_us-gaap_DisposalGroupIncludingDiscontinuedOperationConsideration_D2D40F108E9D54C4D30F0735D4B96210" xlink:type="arc" />
    <link:label id="lab_arnc_DisposalGroupIncludingDiscontinuedOperationConsiderationConsiderationAssets_191F3641C5A2162E6DE40735D4B9E532_terseLabel_en-US" xlink:label="lab_arnc_DisposalGroupIncludingDiscontinuedOperationConsiderationConsiderationAssets_191F3641C5A2162E6DE40735D4B9E532" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Additional contingent consideration</link:label>
    <link:label id="lab_arnc_DisposalGroupIncludingDiscontinuedOperationConsiderationConsiderationAssets_191F3641C5A2162E6DE40735D4B9E532_label_en-US" xlink:label="lab_arnc_DisposalGroupIncludingDiscontinuedOperationConsiderationConsiderationAssets_191F3641C5A2162E6DE40735D4B9E532" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Disposal Group, Including Discontinued Operation, Consideration Consideration, Assets</link:label>
    <link:label id="lab_arnc_DisposalGroupIncludingDiscontinuedOperationConsiderationConsiderationAssets_191F3641C5A2162E6DE40735D4B9E532_documentation_en-US" xlink:label="lab_arnc_DisposalGroupIncludingDiscontinuedOperationConsiderationConsiderationAssets_191F3641C5A2162E6DE40735D4B9E532" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Disposal Group, Including Discontinued Operation, Consideration Consideration, Assets</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_DisposalGroupIncludingDiscontinuedOperationConsiderationConsiderationAssets" xlink:label="loc_arnc_DisposalGroupIncludingDiscontinuedOperationConsiderationConsiderationAssets_191F3641C5A2162E6DE40735D4B9E532" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_DisposalGroupIncludingDiscontinuedOperationConsiderationConsiderationAssets_191F3641C5A2162E6DE40735D4B9E532" xlink:to="lab_arnc_DisposalGroupIncludingDiscontinuedOperationConsiderationConsiderationAssets_191F3641C5A2162E6DE40735D4B9E532" xlink:type="arc" />
    <link:label id="lab_arnc_PeriodofOperationalizingRollingMillEquipmentofTransactionClosingDate_008844ACA850C5D2F2570735D4B9B4F7_terseLabel_en-US" xlink:label="lab_arnc_PeriodofOperationalizingRollingMillEquipmentofTransactionClosingDate_008844ACA850C5D2F2570735D4B9B4F7" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Period of operationalizing rolling mill equipment of transaction closing date</link:label>
    <link:label id="lab_arnc_PeriodofOperationalizingRollingMillEquipmentofTransactionClosingDate_008844ACA850C5D2F2570735D4B9B4F7_label_en-US" xlink:label="lab_arnc_PeriodofOperationalizingRollingMillEquipmentofTransactionClosingDate_008844ACA850C5D2F2570735D4B9B4F7" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Period of Operationalizing Rolling Mill Equipment of Transaction Closing Date</link:label>
    <link:label id="lab_arnc_PeriodofOperationalizingRollingMillEquipmentofTransactionClosingDate_008844ACA850C5D2F2570735D4B9B4F7_documentation_en-US" xlink:label="lab_arnc_PeriodofOperationalizingRollingMillEquipmentofTransactionClosingDate_008844ACA850C5D2F2570735D4B9B4F7" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Period of Operationalizing Rolling Mill Equipment of Transaction Closing Date</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_PeriodofOperationalizingRollingMillEquipmentofTransactionClosingDate" xlink:label="loc_arnc_PeriodofOperationalizingRollingMillEquipmentofTransactionClosingDate_008844ACA850C5D2F2570735D4B9B4F7" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_PeriodofOperationalizingRollingMillEquipmentofTransactionClosingDate_008844ACA850C5D2F2570735D4B9B4F7" xlink:to="lab_arnc_PeriodofOperationalizingRollingMillEquipmentofTransactionClosingDate_008844ACA850C5D2F2570735D4B9B4F7" xlink:type="arc" />
    <link:label id="lab_arnc_MinimumRequiredTermsofLeasesonCastHouseBuildingandEquipment_A2ED474233E86335C9AE0735D4B90ADF_terseLabel_en-US" xlink:label="lab_arnc_MinimumRequiredTermsofLeasesonCastHouseBuildingandEquipment_A2ED474233E86335C9AE0735D4B90ADF" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Minimum required terms of leases on cast house building and equipment</link:label>
    <link:label id="lab_arnc_MinimumRequiredTermsofLeasesonCastHouseBuildingandEquipment_A2ED474233E86335C9AE0735D4B90ADF_label_en-US" xlink:label="lab_arnc_MinimumRequiredTermsofLeasesonCastHouseBuildingandEquipment_A2ED474233E86335C9AE0735D4B90ADF" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Minimum Required Terms of Leases on Cast House Building and Equipment</link:label>
    <link:label id="lab_arnc_MinimumRequiredTermsofLeasesonCastHouseBuildingandEquipment_A2ED474233E86335C9AE0735D4B90ADF_documentation_en-US" xlink:label="lab_arnc_MinimumRequiredTermsofLeasesonCastHouseBuildingandEquipment_A2ED474233E86335C9AE0735D4B90ADF" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Minimum Required Terms of Leases on Cast House Building and Equipment</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_MinimumRequiredTermsofLeasesonCastHouseBuildingandEquipment" xlink:label="loc_arnc_MinimumRequiredTermsofLeasesonCastHouseBuildingandEquipment_A2ED474233E86335C9AE0735D4B90ADF" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_MinimumRequiredTermsofLeasesonCastHouseBuildingandEquipment_A2ED474233E86335C9AE0735D4B90ADF" xlink:to="lab_arnc_MinimumRequiredTermsofLeasesonCastHouseBuildingandEquipment_A2ED474233E86335C9AE0735D4B90ADF" xlink:type="arc" />
    <link:label id="lab_arnc_PeriodofServicesPerformedProcessingofMetal_AE373FC543C86F623E960735D4B9E77D_terseLabel_en-US" xlink:label="lab_arnc_PeriodofServicesPerformedProcessingofMetal_AE373FC543C86F623E960735D4B9E77D" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Period of services performed, processing of metal</link:label>
    <link:label id="lab_arnc_PeriodofServicesPerformedProcessingofMetal_AE373FC543C86F623E960735D4B9E77D_label_en-US" xlink:label="lab_arnc_PeriodofServicesPerformedProcessingofMetal_AE373FC543C86F623E960735D4B9E77D" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Period of Services Performed, Processing of Metal</link:label>
    <link:label id="lab_arnc_PeriodofServicesPerformedProcessingofMetal_AE373FC543C86F623E960735D4B9E77D_documentation_en-US" xlink:label="lab_arnc_PeriodofServicesPerformedProcessingofMetal_AE373FC543C86F623E960735D4B9E77D" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Period of Services Performed, Processing of Metal</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_PeriodofServicesPerformedProcessingofMetal" xlink:label="loc_arnc_PeriodofServicesPerformedProcessingofMetal_AE373FC543C86F623E960735D4B9E77D" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_PeriodofServicesPerformedProcessingofMetal_AE373FC543C86F623E960735D4B9E77D" xlink:to="lab_arnc_PeriodofServicesPerformedProcessingofMetal_AE373FC543C86F623E960735D4B9E77D" xlink:type="arc" />
    <link:label id="lab_arnc_PeriodofSupplywithAluminum_324A80E139A7B4C1FF2A0735D4B9EC8C_terseLabel_en-US" xlink:label="lab_arnc_PeriodofSupplywithAluminum_324A80E139A7B4C1FF2A0735D4B9EC8C" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Period of supply with aluminum</link:label>
    <link:label id="lab_arnc_PeriodofSupplywithAluminum_324A80E139A7B4C1FF2A0735D4B9EC8C_label_en-US" xlink:label="lab_arnc_PeriodofSupplywithAluminum_324A80E139A7B4C1FF2A0735D4B9EC8C" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Period of Supply with Aluminum</link:label>
    <link:label id="lab_arnc_PeriodofSupplywithAluminum_324A80E139A7B4C1FF2A0735D4B9EC8C_documentation_en-US" xlink:label="lab_arnc_PeriodofSupplywithAluminum_324A80E139A7B4C1FF2A0735D4B9EC8C" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Period of Supply with Aluminum</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_PeriodofSupplywithAluminum" xlink:label="loc_arnc_PeriodofSupplywithAluminum_324A80E139A7B4C1FF2A0735D4B9EC8C" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_PeriodofSupplywithAluminum_324A80E139A7B4C1FF2A0735D4B9EC8C" xlink:to="lab_arnc_PeriodofSupplywithAluminum_324A80E139A7B4C1FF2A0735D4B9EC8C" xlink:type="arc" />
    <link:label id="lab_us-gaap_GainLossOnSaleOfBusiness_0A4B10B831A3C175A8C60735D4B9C083_terseLabel_en-US" xlink:label="lab_us-gaap_GainLossOnSaleOfBusiness_0A4B10B831A3C175A8C60735D4B9C083" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Gain (loss) on disposition of business</link:label>
    <link:label id="lab_us-gaap_GainLossOnSaleOfBusiness_0A4B10B831A3C175A8C60735D4B9C083_label_en-US" xlink:label="lab_us-gaap_GainLossOnSaleOfBusiness_0A4B10B831A3C175A8C60735D4B9C083" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Gain (Loss) on Disposition of Business</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_GainLossOnSaleOfBusiness" xlink:label="loc_us-gaap_GainLossOnSaleOfBusiness_0A4B10B831A3C175A8C60735D4B9C083" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_GainLossOnSaleOfBusiness_0A4B10B831A3C175A8C60735D4B9C083" xlink:to="lab_us-gaap_GainLossOnSaleOfBusiness_0A4B10B831A3C175A8C60735D4B9C083" xlink:type="arc" />
    <link:label id="lab_us-gaap_BusinessCombinationContingentConsiderationAsset_7D2D97D3208B6A351CF40735D4B93A0B_terseLabel_en-US" xlink:label="lab_us-gaap_BusinessCombinationContingentConsiderationAsset_7D2D97D3208B6A351CF40735D4B93A0B" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Contingent consideration</link:label>
    <link:label id="lab_us-gaap_BusinessCombinationContingentConsiderationAsset_7D2D97D3208B6A351CF40735D4B93A0B_label_en-US" xlink:label="lab_us-gaap_BusinessCombinationContingentConsiderationAsset_7D2D97D3208B6A351CF40735D4B93A0B" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Business Combination, Contingent Consideration, Asset</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_BusinessCombinationContingentConsiderationAsset" xlink:label="loc_us-gaap_BusinessCombinationContingentConsiderationAsset_7D2D97D3208B6A351CF40735D4B93A0B" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_BusinessCombinationContingentConsiderationAsset_7D2D97D3208B6A351CF40735D4B93A0B" xlink:to="lab_us-gaap_BusinessCombinationContingentConsiderationAsset_7D2D97D3208B6A351CF40735D4B93A0B" xlink:type="arc" />
    <link:label id="lab_us-gaap_DeferredGainOnSaleOfProperty_51F559B4E60D752C1F120735D4B9128D_terseLabel_en-US" xlink:label="lab_us-gaap_DeferredGainOnSaleOfProperty_51F559B4E60D752C1F120735D4B9128D" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Deferred gain on sale of property</link:label>
    <link:label id="lab_us-gaap_DeferredGainOnSaleOfProperty_51F559B4E60D752C1F120735D4B9128D_label_en-US" xlink:label="lab_us-gaap_DeferredGainOnSaleOfProperty_51F559B4E60D752C1F120735D4B9128D" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Deferred Gain on Sale of Property</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DeferredGainOnSaleOfProperty" xlink:label="loc_us-gaap_DeferredGainOnSaleOfProperty_51F559B4E60D752C1F120735D4B9128D" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DeferredGainOnSaleOfProperty_51F559B4E60D752C1F120735D4B9128D" xlink:to="lab_us-gaap_DeferredGainOnSaleOfProperty_51F559B4E60D752C1F120735D4B9128D" xlink:type="arc" />
    <link:label id="lab_us-gaap_DiscontinuedOperationsAndDisposalGroupsAbstract_CC571A66CB1909243A42E244A8B65CD8_label_en-US" xlink:label="lab_us-gaap_DiscontinuedOperationsAndDisposalGroupsAbstract_CC571A66CB1909243A42E244A8B65CD8" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Discontinued Operations and Disposal Groups [Abstract]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DiscontinuedOperationsAndDisposalGroupsAbstract" xlink:label="loc_us-gaap_DiscontinuedOperationsAndDisposalGroupsAbstract_CC571A66CB1909243A42E244A8B65CD8" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DiscontinuedOperationsAndDisposalGroupsAbstract_CC571A66CB1909243A42E244A8B65CD8" xlink:to="lab_us-gaap_DiscontinuedOperationsAndDisposalGroupsAbstract_CC571A66CB1909243A42E244A8B65CD8" xlink:type="arc" />
    <link:label id="lab_us-gaap_ScheduleOfDisposalGroupsIncludingDiscontinuedOperationsIncomeStatementBalanceSheetAndAdditionalDisclosuresTextBlock_1FC2D0FFFFF81E0EBF97E244A8BAB9C1_terseLabel_en-US" xlink:label="lab_us-gaap_ScheduleOfDisposalGroupsIncludingDiscontinuedOperationsIncomeStatementBalanceSheetAndAdditionalDisclosuresTextBlock_1FC2D0FFFFF81E0EBF97E244A8BAB9C1" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Summary of Discontinued Operations in Financial Statements</link:label>
    <link:label id="lab_us-gaap_ScheduleOfDisposalGroupsIncludingDiscontinuedOperationsIncomeStatementBalanceSheetAndAdditionalDisclosuresTextBlock_1FC2D0FFFFF81E0EBF97E244A8BAB9C1_label_en-US" xlink:label="lab_us-gaap_ScheduleOfDisposalGroupsIncludingDiscontinuedOperationsIncomeStatementBalanceSheetAndAdditionalDisclosuresTextBlock_1FC2D0FFFFF81E0EBF97E244A8BAB9C1" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Disposal Groups, Including Discontinued Operations [Table Text Block]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ScheduleOfDisposalGroupsIncludingDiscontinuedOperationsIncomeStatementBalanceSheetAndAdditionalDisclosuresTextBlock" xlink:label="loc_us-gaap_ScheduleOfDisposalGroupsIncludingDiscontinuedOperationsIncomeStatementBalanceSheetAndAdditionalDisclosuresTextBlock_1FC2D0FFFFF81E0EBF97E244A8BAB9C1" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfDisposalGroupsIncludingDiscontinuedOperationsIncomeStatementBalanceSheetAndAdditionalDisclosuresTextBlock_1FC2D0FFFFF81E0EBF97E244A8BAB9C1" xlink:to="lab_us-gaap_ScheduleOfDisposalGroupsIncludingDiscontinuedOperationsIncomeStatementBalanceSheetAndAdditionalDisclosuresTextBlock_1FC2D0FFFFF81E0EBF97E244A8BAB9C1" xlink:type="arc" />
    <link:label id="lab_arnc_DisposalGroupsIncludingDiscontinuedOperationsScheduleOfDepreciationDepletionAndAmortizationTableTextBlock_862ABAFA5D5EB2D9E2B5E244A8BA09DD_terseLabel_en-US" xlink:label="lab_arnc_DisposalGroupsIncludingDiscontinuedOperationsScheduleOfDepreciationDepletionAndAmortizationTableTextBlock_862ABAFA5D5EB2D9E2B5E244A8BA09DD" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Disposal Groups, Including Discontinued Operations, Schedule Of Depreciation, Depletion, And Amortization</link:label>
    <link:label id="lab_arnc_DisposalGroupsIncludingDiscontinuedOperationsScheduleOfDepreciationDepletionAndAmortizationTableTextBlock_862ABAFA5D5EB2D9E2B5E244A8BA09DD_label_en-US" xlink:label="lab_arnc_DisposalGroupsIncludingDiscontinuedOperationsScheduleOfDepreciationDepletionAndAmortizationTableTextBlock_862ABAFA5D5EB2D9E2B5E244A8BA09DD" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Disposal Groups, Including Discontinued Operations, Schedule Of Depreciation, Depletion, And Amortization [Table Text Block]</link:label>
    <link:label id="lab_arnc_DisposalGroupsIncludingDiscontinuedOperationsScheduleOfDepreciationDepletionAndAmortizationTableTextBlock_862ABAFA5D5EB2D9E2B5E244A8BA09DD_documentation_en-US" xlink:label="lab_arnc_DisposalGroupsIncludingDiscontinuedOperationsScheduleOfDepreciationDepletionAndAmortizationTableTextBlock_862ABAFA5D5EB2D9E2B5E244A8BA09DD" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Disposal Groups, Including Discontinued Operations, Schedule Of Depreciation, Depletion, And Amortization [Table Text Block]</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_DisposalGroupsIncludingDiscontinuedOperationsScheduleOfDepreciationDepletionAndAmortizationTableTextBlock" xlink:label="loc_arnc_DisposalGroupsIncludingDiscontinuedOperationsScheduleOfDepreciationDepletionAndAmortizationTableTextBlock_862ABAFA5D5EB2D9E2B5E244A8BA09DD" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_DisposalGroupsIncludingDiscontinuedOperationsScheduleOfDepreciationDepletionAndAmortizationTableTextBlock_862ABAFA5D5EB2D9E2B5E244A8BA09DD" xlink:to="lab_arnc_DisposalGroupsIncludingDiscontinuedOperationsScheduleOfDepreciationDepletionAndAmortizationTableTextBlock_862ABAFA5D5EB2D9E2B5E244A8BA09DD" xlink:type="arc" />
    <link:label id="lab_us-gaap_MergersAcquisitionsAndDispositionsDisclosuresTextBlock_EF292E0AF7B7774325D6E244A93EDED9_terseLabel_en-US" xlink:label="lab_us-gaap_MergersAcquisitionsAndDispositionsDisclosuresTextBlock_EF292E0AF7B7774325D6E244A93EDED9" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Acquisitions and Divestitures</link:label>
    <link:label id="lab_us-gaap_MergersAcquisitionsAndDispositionsDisclosuresTextBlock_EF292E0AF7B7774325D6E244A93EDED9_label_en-US" xlink:label="lab_us-gaap_MergersAcquisitionsAndDispositionsDisclosuresTextBlock_EF292E0AF7B7774325D6E244A93EDED9" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Mergers, Acquisitions and Dispositions Disclosures [Text Block]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_MergersAcquisitionsAndDispositionsDisclosuresTextBlock" xlink:label="loc_us-gaap_MergersAcquisitionsAndDispositionsDisclosuresTextBlock_EF292E0AF7B7774325D6E244A93EDED9" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_MergersAcquisitionsAndDispositionsDisclosuresTextBlock_EF292E0AF7B7774325D6E244A93EDED9" xlink:to="lab_us-gaap_MergersAcquisitionsAndDispositionsDisclosuresTextBlock_EF292E0AF7B7774325D6E244A93EDED9" xlink:type="arc" />
    <link:label id="lab_us-gaap_FairValueByAssetClassAxis_1EC204460C5808DC49B0E244A91EB9FA_terseLabel_en-US" xlink:label="lab_us-gaap_FairValueByAssetClassAxis_1EC204460C5808DC49B0E244A91EB9FA" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Asset Class [Axis]</link:label>
    <link:label id="lab_us-gaap_FairValueByAssetClassAxis_1EC204460C5808DC49B0E244A91EB9FA_label_en-US" xlink:label="lab_us-gaap_FairValueByAssetClassAxis_1EC204460C5808DC49B0E244A91EB9FA" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Asset Class [Axis]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_FairValueByAssetClassAxis" xlink:label="loc_us-gaap_FairValueByAssetClassAxis_1EC204460C5808DC49B0E244A91EB9FA" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FairValueByAssetClassAxis_1EC204460C5808DC49B0E244A91EB9FA" xlink:to="lab_us-gaap_FairValueByAssetClassAxis_1EC204460C5808DC49B0E244A91EB9FA" xlink:type="arc" />
    <link:label id="lab_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain_A3AB2F31B51A9A4E7F81E244A91E0758_terseLabel_en-US" xlink:label="lab_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain_A3AB2F31B51A9A4E7F81E244A91E0758" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Asset Class [Domain]</link:label>
    <link:label id="lab_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain_A3AB2F31B51A9A4E7F81E244A91E0758_label_en-US" xlink:label="lab_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain_A3AB2F31B51A9A4E7F81E244A91E0758" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Asset Class [Domain]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain" xlink:label="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain_A3AB2F31B51A9A4E7F81E244A91E0758" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain_A3AB2F31B51A9A4E7F81E244A91E0758" xlink:to="lab_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain_A3AB2F31B51A9A4E7F81E244A91E0758" xlink:type="arc" />
    <link:label id="lab_us-gaap_GoodwillMember_1FCE12D5F09CFB045528E244A91E0FC9_terseLabel_en-US" xlink:label="lab_us-gaap_GoodwillMember_1FCE12D5F09CFB045528E244A91E0FC9" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Goodwill</link:label>
    <link:label id="lab_us-gaap_GoodwillMember_1FCE12D5F09CFB045528E244A91E0FC9_label_en-US" xlink:label="lab_us-gaap_GoodwillMember_1FCE12D5F09CFB045528E244A91E0FC9" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Goodwill [Member]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_GoodwillMember" xlink:label="loc_us-gaap_GoodwillMember_1FCE12D5F09CFB045528E244A91E0FC9" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_GoodwillMember_1FCE12D5F09CFB045528E244A91E0FC9" xlink:to="lab_us-gaap_GoodwillMember_1FCE12D5F09CFB045528E244A91E0FC9" xlink:type="arc" />
    <link:label id="lab_us-gaap_BusinessAcquisitionAxis_F485BD51316D00AABF07E244A91E0DFB_terseLabel_en-US" xlink:label="lab_us-gaap_BusinessAcquisitionAxis_F485BD51316D00AABF07E244A91E0DFB" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Business Acquisition [Axis]</link:label>
    <link:label id="lab_us-gaap_BusinessAcquisitionAxis_F485BD51316D00AABF07E244A91E0DFB_label_en-US" xlink:label="lab_us-gaap_BusinessAcquisitionAxis_F485BD51316D00AABF07E244A91E0DFB" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Business Acquisition [Axis]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_BusinessAcquisitionAxis" xlink:label="loc_us-gaap_BusinessAcquisitionAxis_F485BD51316D00AABF07E244A91E0DFB" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_BusinessAcquisitionAxis_F485BD51316D00AABF07E244A91E0DFB" xlink:to="lab_us-gaap_BusinessAcquisitionAxis_F485BD51316D00AABF07E244A91E0DFB" xlink:type="arc" />
    <link:label id="lab_us-gaap_BusinessAcquisitionAcquireeDomain_12586F13BB0A11972692E244A91E0220_terseLabel_en-US" xlink:label="lab_us-gaap_BusinessAcquisitionAcquireeDomain_12586F13BB0A11972692E244A91E0220" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Business Acquisition, Acquiree [Domain]</link:label>
    <link:label id="lab_us-gaap_BusinessAcquisitionAcquireeDomain_12586F13BB0A11972692E244A91E0220_label_en-US" xlink:label="lab_us-gaap_BusinessAcquisitionAcquireeDomain_12586F13BB0A11972692E244A91E0220" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Business Acquisition, Acquiree [Domain]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_BusinessAcquisitionAcquireeDomain" xlink:label="loc_us-gaap_BusinessAcquisitionAcquireeDomain_12586F13BB0A11972692E244A91E0220" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_BusinessAcquisitionAcquireeDomain_12586F13BB0A11972692E244A91E0220" xlink:to="lab_us-gaap_BusinessAcquisitionAcquireeDomain_12586F13BB0A11972692E244A91E0220" xlink:type="arc" />
    <link:label id="lab_arnc_RTIMember_B7A5780B5C5014B5EE37E244A91E5202_terseLabel_en-US" xlink:label="lab_arnc_RTIMember_B7A5780B5C5014B5EE37E244A91E5202" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">RTI</link:label>
    <link:label id="lab_arnc_RTIMember_B7A5780B5C5014B5EE37E244A91E5202_label_en-US" xlink:label="lab_arnc_RTIMember_B7A5780B5C5014B5EE37E244A91E5202" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">RTI [Member]</link:label>
    <link:label id="lab_arnc_RTIMember_B7A5780B5C5014B5EE37E244A91E5202_documentation_en-US" xlink:label="lab_arnc_RTIMember_B7A5780B5C5014B5EE37E244A91E5202" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">RTI [Member]</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_RTIMember" xlink:label="loc_arnc_RTIMember_B7A5780B5C5014B5EE37E244A91E5202" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_RTIMember_B7A5780B5C5014B5EE37E244A91E5202" xlink:to="lab_arnc_RTIMember_B7A5780B5C5014B5EE37E244A91E5202" xlink:type="arc" />
    <link:label id="lab_arnc_LisiMedicalMember_AA5953BF767C959120FCE244A9227052_terseLabel_en-US" xlink:label="lab_arnc_LisiMedicalMember_AA5953BF767C959120FCE244A9227052" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">LISI MEDICAL</link:label>
    <link:label id="lab_arnc_LisiMedicalMember_AA5953BF767C959120FCE244A9227052_label_en-US" xlink:label="lab_arnc_LisiMedicalMember_AA5953BF767C959120FCE244A9227052" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">LISI MEDICAL [Member]</link:label>
    <link:label id="lab_arnc_LisiMedicalMember_AA5953BF767C959120FCE244A9227052_documentation_en-US" xlink:label="lab_arnc_LisiMedicalMember_AA5953BF767C959120FCE244A9227052" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">LISI MEDICAL.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_LisiMedicalMember" xlink:label="loc_arnc_LisiMedicalMember_AA5953BF767C959120FCE244A9227052" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_LisiMedicalMember_AA5953BF767C959120FCE244A9227052" xlink:to="lab_arnc_LisiMedicalMember_AA5953BF767C959120FCE244A9227052" xlink:type="arc" />
    <link:label id="lab_us-gaap_ProceedsFromDivestitureOfBusinesses_C27A9FDB0131DD9E7DD3E244A92230CD_verboseLabel_en-US" xlink:label="lab_us-gaap_ProceedsFromDivestitureOfBusinesses_C27A9FDB0131DD9E7DD3E244A92230CD" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Proceeds from divestiture of businesses</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ProceedsFromDivestitureOfBusinesses" xlink:label="loc_us-gaap_ProceedsFromDivestitureOfBusinesses_C27A9FDB0131DD9E7DD3E244A92230CD" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ProceedsFromDivestitureOfBusinesses_C27A9FDB0131DD9E7DD3E244A92230CD" xlink:to="lab_us-gaap_ProceedsFromDivestitureOfBusinesses_C27A9FDB0131DD9E7DD3E244A92230CD" xlink:type="arc" />
    <link:label id="lab_us-gaap_DisposalGroupIncludingDiscontinuedOperationConsideration_387E854F361827B285E3E244A9225CFD_verboseLabel_en-US" xlink:label="lab_us-gaap_DisposalGroupIncludingDiscontinuedOperationConsideration_387E854F361827B285E3E244A9225CFD" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Proceeds from divestiture of businesses net of transaction costs</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DisposalGroupIncludingDiscontinuedOperationConsideration" xlink:label="loc_us-gaap_DisposalGroupIncludingDiscontinuedOperationConsideration_387E854F361827B285E3E244A9225CFD" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DisposalGroupIncludingDiscontinuedOperationConsideration_387E854F361827B285E3E244A9225CFD" xlink:to="lab_us-gaap_DisposalGroupIncludingDiscontinuedOperationConsideration_387E854F361827B285E3E244A9225CFD" xlink:type="arc" />
    <link:label id="lab_us-gaap_DisposalGroupDeferredGainOnDisposal_ABB11E581C6F01FD7437E244A92246F7_verboseLabel_en-US" xlink:label="lab_us-gaap_DisposalGroupDeferredGainOnDisposal_ABB11E581C6F01FD7437E244A92246F7" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Disposal group, deferred gain on disposal</link:label>
    <link:label id="lab_us-gaap_DisposalGroupDeferredGainOnDisposal_ABB11E581C6F01FD7437E244A92246F7_label_en-US" xlink:label="lab_us-gaap_DisposalGroupDeferredGainOnDisposal_ABB11E581C6F01FD7437E244A92246F7" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Disposal Group, Deferred Gain on Disposal</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DisposalGroupDeferredGainOnDisposal" xlink:label="loc_us-gaap_DisposalGroupDeferredGainOnDisposal_ABB11E581C6F01FD7437E244A92246F7" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DisposalGroupDeferredGainOnDisposal_ABB11E581C6F01FD7437E244A92246F7" xlink:to="lab_us-gaap_DisposalGroupDeferredGainOnDisposal_ABB11E581C6F01FD7437E244A92246F7" xlink:type="arc" />
    <link:label id="lab_us-gaap_BusinessCombinationProvisionalInformationInitialAccountingIncompleteAdjustmentIntangibles_EFD8124EBFDD18BAC66FE244A922A714_terseLabel_en-US" xlink:label="lab_us-gaap_BusinessCombinationProvisionalInformationInitialAccountingIncompleteAdjustmentIntangibles_EFD8124EBFDD18BAC66FE244A922A714" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Increase (decrease) intangible assets</link:label>
    <link:label id="lab_us-gaap_BusinessCombinationProvisionalInformationInitialAccountingIncompleteAdjustmentIntangibles_EFD8124EBFDD18BAC66FE244A922A714_label_en-US" xlink:label="lab_us-gaap_BusinessCombinationProvisionalInformationInitialAccountingIncompleteAdjustmentIntangibles_EFD8124EBFDD18BAC66FE244A922A714" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Intangibles</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_BusinessCombinationProvisionalInformationInitialAccountingIncompleteAdjustmentIntangibles" xlink:label="loc_us-gaap_BusinessCombinationProvisionalInformationInitialAccountingIncompleteAdjustmentIntangibles_EFD8124EBFDD18BAC66FE244A922A714" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_BusinessCombinationProvisionalInformationInitialAccountingIncompleteAdjustmentIntangibles_EFD8124EBFDD18BAC66FE244A922A714" xlink:to="lab_us-gaap_BusinessCombinationProvisionalInformationInitialAccountingIncompleteAdjustmentIntangibles_EFD8124EBFDD18BAC66FE244A922A714" xlink:type="arc" />
    <link:label id="lab_us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_4F7DA8CC26F38B957BE7E244A9220142_verboseLabel_en-US" xlink:label="lab_us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_4F7DA8CC26F38B957BE7E244A9220142" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Sales</link:label>
    <link:label id="lab_us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_4F7DA8CC26F38B957BE7E244A9220142_label_en-US" xlink:label="lab_us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_4F7DA8CC26F38B957BE7E244A9220142" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Revenue from Contract with Customer, Excluding Assessed Tax</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax" xlink:label="loc_us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_4F7DA8CC26F38B957BE7E244A9220142" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_4F7DA8CC26F38B957BE7E244A9220142" xlink:to="lab_us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_4F7DA8CC26F38B957BE7E244A9220142" xlink:type="arc" />
    <link:label id="lab_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsTable_29E9B272AAB62DF1EE83E244A89A8BEB_terseLabel_en-US" xlink:label="lab_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsTable_29E9B272AAB62DF1EE83E244A89A8BEB" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Disposal Groups, Including Discontinued Operations [Table]</link:label>
    <link:label id="lab_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsTable_29E9B272AAB62DF1EE83E244A89A8BEB_label_en-US" xlink:label="lab_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsTable_29E9B272AAB62DF1EE83E244A89A8BEB" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Disposal Groups, Including Discontinued Operations [Table]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsTable" xlink:label="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsTable_29E9B272AAB62DF1EE83E244A89A8BEB" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsTable_29E9B272AAB62DF1EE83E244A89A8BEB" xlink:to="lab_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsTable_29E9B272AAB62DF1EE83E244A89A8BEB" xlink:type="arc" />
    <link:label id="lab_arnc_AlcoaCorporationMember_37BE3D1C36FE14CA5233E244A89A0694_terseLabel_en-US" xlink:label="lab_arnc_AlcoaCorporationMember_37BE3D1C36FE14CA5233E244A89A0694" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Alcoa Corporation</link:label>
    <link:label id="lab_arnc_AlcoaCorporationMember_37BE3D1C36FE14CA5233E244A89A0694_label_en-US" xlink:label="lab_arnc_AlcoaCorporationMember_37BE3D1C36FE14CA5233E244A89A0694" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Alcoa Corporation [Member]</link:label>
    <link:label id="lab_arnc_AlcoaCorporationMember_37BE3D1C36FE14CA5233E244A89A0694_documentation_en-US" xlink:label="lab_arnc_AlcoaCorporationMember_37BE3D1C36FE14CA5233E244A89A0694" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Alcoa corporation.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_AlcoaCorporationMember" xlink:label="loc_arnc_AlcoaCorporationMember_37BE3D1C36FE14CA5233E244A89A0694" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_AlcoaCorporationMember_37BE3D1C36FE14CA5233E244A89A0694" xlink:to="lab_arnc_AlcoaCorporationMember_37BE3D1C36FE14CA5233E244A89A0694" xlink:type="arc" />
    <link:label id="lab_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems_BCFA575A7C4244532EBEE244A89AB7EA_terseLabel_en-US" xlink:label="lab_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems_BCFA575A7C4244532EBEE244A89AB7EA" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]</link:label>
    <link:label id="lab_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems_BCFA575A7C4244532EBEE244A89AB7EA_label_en-US" xlink:label="lab_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems_BCFA575A7C4244532EBEE244A89AB7EA" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems" xlink:label="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems_BCFA575A7C4244532EBEE244A89AB7EA" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems_BCFA575A7C4244532EBEE244A89AB7EA" xlink:to="lab_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems_BCFA575A7C4244532EBEE244A89AB7EA" xlink:type="arc" />
    <link:label id="lab_us-gaap_DepreciationAndAmortizationDiscontinuedOperations_6BB890B5999388283D38E244A89AB7FB_terseLabel_en-US" xlink:label="lab_us-gaap_DepreciationAndAmortizationDiscontinuedOperations_6BB890B5999388283D38E244A89AB7FB" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Depreciation, depletion and amortization</link:label>
    <link:label id="lab_us-gaap_DepreciationAndAmortizationDiscontinuedOperations_6BB890B5999388283D38E244A89AB7FB_label_en-US" xlink:label="lab_us-gaap_DepreciationAndAmortizationDiscontinuedOperations_6BB890B5999388283D38E244A89AB7FB" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Depreciation and Amortization, Discontinued Operations</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DepreciationAndAmortizationDiscontinuedOperations" xlink:label="loc_us-gaap_DepreciationAndAmortizationDiscontinuedOperations_6BB890B5999388283D38E244A89AB7FB" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DepreciationAndAmortizationDiscontinuedOperations_6BB890B5999388283D38E244A89AB7FB" xlink:to="lab_us-gaap_DepreciationAndAmortizationDiscontinuedOperations_6BB890B5999388283D38E244A89AB7FB" xlink:type="arc" />
    <link:label id="lab_arnc_RestructuringAndOtherChargesForDiscontinuedOperations_9A6687F7CA74F50C8173E244A89E9902_terseLabel_en-US" xlink:label="lab_arnc_RestructuringAndOtherChargesForDiscontinuedOperations_9A6687F7CA74F50C8173E244A89E9902" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Restructuring and other charges</link:label>
    <link:label id="lab_arnc_RestructuringAndOtherChargesForDiscontinuedOperations_9A6687F7CA74F50C8173E244A89E9902_label_en-US" xlink:label="lab_arnc_RestructuringAndOtherChargesForDiscontinuedOperations_9A6687F7CA74F50C8173E244A89E9902" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Restructuring And Other Charges For Discontinued Operations</link:label>
    <link:label id="lab_arnc_RestructuringAndOtherChargesForDiscontinuedOperations_9A6687F7CA74F50C8173E244A89E9902_documentation_en-US" xlink:label="lab_arnc_RestructuringAndOtherChargesForDiscontinuedOperations_9A6687F7CA74F50C8173E244A89E9902" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Restructuring and other charges for discontinued operations.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_RestructuringAndOtherChargesForDiscontinuedOperations" xlink:label="loc_arnc_RestructuringAndOtherChargesForDiscontinuedOperations_9A6687F7CA74F50C8173E244A89E9902" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_RestructuringAndOtherChargesForDiscontinuedOperations_9A6687F7CA74F50C8173E244A89E9902" xlink:to="lab_arnc_RestructuringAndOtherChargesForDiscontinuedOperations_9A6687F7CA74F50C8173E244A89E9902" xlink:type="arc" />
    <link:label id="lab_us-gaap_CapitalExpenditureDiscontinuedOperations_C03786C72AF75378896FE244A89EC6E4_terseLabel_en-US" xlink:label="lab_us-gaap_CapitalExpenditureDiscontinuedOperations_C03786C72AF75378896FE244A89EC6E4" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Capital expenditures</link:label>
    <link:label id="lab_us-gaap_CapitalExpenditureDiscontinuedOperations_C03786C72AF75378896FE244A89EC6E4_label_en-US" xlink:label="lab_us-gaap_CapitalExpenditureDiscontinuedOperations_C03786C72AF75378896FE244A89EC6E4" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Capital Expenditure, Discontinued Operations</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_CapitalExpenditureDiscontinuedOperations" xlink:label="loc_us-gaap_CapitalExpenditureDiscontinuedOperations_C03786C72AF75378896FE244A89EC6E4" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CapitalExpenditureDiscontinuedOperations_C03786C72AF75378896FE244A89EC6E4" xlink:to="lab_us-gaap_CapitalExpenditureDiscontinuedOperations_C03786C72AF75378896FE244A89EC6E4" xlink:type="arc" />
    <link:label id="lab_us-gaap_IncomeTaxDisclosureAbstract_72110479FA237531E9657C362EA91FD9_label_en-US" xlink:label="lab_us-gaap_IncomeTaxDisclosureAbstract_72110479FA237531E9657C362EA91FD9" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Income Tax Disclosure [Abstract]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_IncomeTaxDisclosureAbstract" xlink:label="loc_us-gaap_IncomeTaxDisclosureAbstract_72110479FA237531E9657C362EA91FD9" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncomeTaxDisclosureAbstract_72110479FA237531E9657C362EA91FD9" xlink:to="lab_us-gaap_IncomeTaxDisclosureAbstract_72110479FA237531E9657C362EA91FD9" xlink:type="arc" />
    <link:label id="lab_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic_DEB7FD7A5077B5FF329F7C362EA925DE_terseLabel_en-US" xlink:label="lab_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic_DEB7FD7A5077B5FF329F7C362EA925DE" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">United States</link:label>
    <link:label id="lab_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic_DEB7FD7A5077B5FF329F7C362EA925DE_label_en-US" xlink:label="lab_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic_DEB7FD7A5077B5FF329F7C362EA925DE" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Income (Loss) from Continuing Operations before Income Taxes, Domestic</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic" xlink:label="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic_DEB7FD7A5077B5FF329F7C362EA925DE" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic_DEB7FD7A5077B5FF329F7C362EA925DE" xlink:to="lab_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic_DEB7FD7A5077B5FF329F7C362EA925DE" xlink:type="arc" />
    <link:label id="lab_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesForeign_BA9C1AD37374646468967C362EA9E9D4_terseLabel_en-US" xlink:label="lab_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesForeign_BA9C1AD37374646468967C362EA9E9D4" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Foreign</link:label>
    <link:label id="lab_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesForeign_BA9C1AD37374646468967C362EA9E9D4_label_en-US" xlink:label="lab_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesForeign_BA9C1AD37374646468967C362EA9E9D4" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Income (Loss) from Continuing Operations before Income Taxes, Foreign</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesForeign" xlink:label="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesForeign_BA9C1AD37374646468967C362EA9E9D4" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesForeign_BA9C1AD37374646468967C362EA9E9D4" xlink:to="lab_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesForeign_BA9C1AD37374646468967C362EA9E9D4" xlink:type="arc" />
    <link:label id="lab_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments_4C0824CA511E6D71CBDE7C362EA9BD40_totalLabel_en-US" xlink:label="lab_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments_4C0824CA511E6D71CBDE7C362EA9BD40" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Income from continuing operations before income taxes</link:label>
    <link:label id="lab_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments_4C0824CA511E6D71CBDE7C362EA9BD40_label_en-US" xlink:label="lab_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments_4C0824CA511E6D71CBDE7C362EA9BD40" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Income (Loss) from Continuing Operations before Equity Method Investments, Income Taxes, Noncontrolling Interest</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments" xlink:label="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments_4C0824CA511E6D71CBDE7C362EA9BD40" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments_4C0824CA511E6D71CBDE7C362EA9BD40" xlink:to="lab_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments_4C0824CA511E6D71CBDE7C362EA9BD40" xlink:type="arc" />
    <link:label id="lab_us-gaap_SegmentReportingAbstract_A4A8AD09DF496390D61D7C36305E22AA_label_en-US" xlink:label="lab_us-gaap_SegmentReportingAbstract_A4A8AD09DF496390D61D7C36305E22AA" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Segment Reporting [Abstract]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_SegmentReportingAbstract" xlink:label="loc_us-gaap_SegmentReportingAbstract_A4A8AD09DF496390D61D7C36305E22AA" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SegmentReportingAbstract_A4A8AD09DF496390D61D7C36305E22AA" xlink:to="lab_us-gaap_SegmentReportingAbstract_A4A8AD09DF496390D61D7C36305E22AA" xlink:type="arc" />
    <link:label id="lab_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTextBlock_D148ED465EB1B372938B7C36305E33CB_terseLabel_en-US" xlink:label="lab_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTextBlock_D148ED465EB1B372938B7C36305E33CB" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Schedule of Operating Results and Assets of Arconic's Reportable Segments</link:label>
    <link:label id="lab_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTextBlock_D148ED465EB1B372938B7C36305E33CB_label_en-US" xlink:label="lab_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTextBlock_D148ED465EB1B372938B7C36305E33CB" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Schedule of Segment Reporting Information, by Segment [Table Text Block]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ScheduleOfSegmentReportingInformationBySegmentTextBlock" xlink:label="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTextBlock_D148ED465EB1B372938B7C36305E33CB" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTextBlock_D148ED465EB1B372938B7C36305E33CB" xlink:to="lab_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTextBlock_D148ED465EB1B372938B7C36305E33CB" xlink:type="arc" />
    <link:label id="lab_us-gaap_ReconciliationOfRevenueFromSegmentsToConsolidatedTextBlock_645545DE884462D1681A7C36305E419A_terseLabel_en-US" xlink:label="lab_us-gaap_ReconciliationOfRevenueFromSegmentsToConsolidatedTextBlock_645545DE884462D1681A7C36305E419A" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Schedule of Reconciliation of Certain Segment Information to Consolidated Totals</link:label>
    <link:label id="lab_us-gaap_ReconciliationOfRevenueFromSegmentsToConsolidatedTextBlock_645545DE884462D1681A7C36305E419A_label_en-US" xlink:label="lab_us-gaap_ReconciliationOfRevenueFromSegmentsToConsolidatedTextBlock_645545DE884462D1681A7C36305E419A" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Reconciliation of Revenue from Segments to Consolidated [Table Text Block]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ReconciliationOfRevenueFromSegmentsToConsolidatedTextBlock" xlink:label="loc_us-gaap_ReconciliationOfRevenueFromSegmentsToConsolidatedTextBlock_645545DE884462D1681A7C36305E419A" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ReconciliationOfRevenueFromSegmentsToConsolidatedTextBlock_645545DE884462D1681A7C36305E419A" xlink:to="lab_us-gaap_ReconciliationOfRevenueFromSegmentsToConsolidatedTextBlock_645545DE884462D1681A7C36305E419A" xlink:type="arc" />
    <link:label id="lab_arnc_ScheduleOfSegmentReportingInformationToConsolidateNetIncomeLossAttributableToParentTextBlock_2C80426160D6A476A6827C36305E6CAE_terseLabel_en-US" xlink:label="lab_arnc_ScheduleOfSegmentReportingInformationToConsolidateNetIncomeLossAttributableToParentTextBlock_2C80426160D6A476A6827C36305E6CAE" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Schedule of Segment ATOI to Consolidated Net (Loss) Income Attributable to Arconic</link:label>
    <link:label id="lab_arnc_ScheduleOfSegmentReportingInformationToConsolidateNetIncomeLossAttributableToParentTextBlock_2C80426160D6A476A6827C36305E6CAE_label_en-US" xlink:label="lab_arnc_ScheduleOfSegmentReportingInformationToConsolidateNetIncomeLossAttributableToParentTextBlock_2C80426160D6A476A6827C36305E6CAE" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Schedule Of Segment Reporting Information To Consolidate Net Income Loss Attributable To Parent [Text Block]</link:label>
    <link:label id="lab_arnc_ScheduleOfSegmentReportingInformationToConsolidateNetIncomeLossAttributableToParentTextBlock_2C80426160D6A476A6827C36305E6CAE_documentation_en-US" xlink:label="lab_arnc_ScheduleOfSegmentReportingInformationToConsolidateNetIncomeLossAttributableToParentTextBlock_2C80426160D6A476A6827C36305E6CAE" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Schedule Of Segment Reporting Information To Consolidate Net Income Loss Attributable To Parent [Text Block]</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_ScheduleOfSegmentReportingInformationToConsolidateNetIncomeLossAttributableToParentTextBlock" xlink:label="loc_arnc_ScheduleOfSegmentReportingInformationToConsolidateNetIncomeLossAttributableToParentTextBlock_2C80426160D6A476A6827C36305E6CAE" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_ScheduleOfSegmentReportingInformationToConsolidateNetIncomeLossAttributableToParentTextBlock_2C80426160D6A476A6827C36305E6CAE" xlink:to="lab_arnc_ScheduleOfSegmentReportingInformationToConsolidateNetIncomeLossAttributableToParentTextBlock_2C80426160D6A476A6827C36305E6CAE" xlink:type="arc" />
    <link:label id="lab_us-gaap_ReconciliationOfAssetsFromSegmentToConsolidatedTextBlock_176012208CB5597D8DB47C36305E91CF_terseLabel_en-US" xlink:label="lab_us-gaap_ReconciliationOfAssetsFromSegmentToConsolidatedTextBlock_176012208CB5597D8DB47C36305E91CF" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Schedule of Segment Reporting Information to Consolidated Assets</link:label>
    <link:label id="lab_us-gaap_ReconciliationOfAssetsFromSegmentToConsolidatedTextBlock_176012208CB5597D8DB47C36305E91CF_label_en-US" xlink:label="lab_us-gaap_ReconciliationOfAssetsFromSegmentToConsolidatedTextBlock_176012208CB5597D8DB47C36305E91CF" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Reconciliation of Assets from Segment to Consolidated [Table Text Block]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ReconciliationOfAssetsFromSegmentToConsolidatedTextBlock" xlink:label="loc_us-gaap_ReconciliationOfAssetsFromSegmentToConsolidatedTextBlock_176012208CB5597D8DB47C36305E91CF" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ReconciliationOfAssetsFromSegmentToConsolidatedTextBlock_176012208CB5597D8DB47C36305E91CF" xlink:to="lab_us-gaap_ReconciliationOfAssetsFromSegmentToConsolidatedTextBlock_176012208CB5597D8DB47C36305E91CF" xlink:type="arc" />
    <link:label id="lab_us-gaap_ScheduleOfProductInformationTableTextBlock_D03CA5023DA1257A9B127C36305ED053_terseLabel_en-US" xlink:label="lab_us-gaap_ScheduleOfProductInformationTableTextBlock_D03CA5023DA1257A9B127C36305ED053" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Sales by Major Product Grouping</link:label>
    <link:label id="lab_us-gaap_ScheduleOfProductInformationTableTextBlock_D03CA5023DA1257A9B127C36305ED053_label_en-US" xlink:label="lab_us-gaap_ScheduleOfProductInformationTableTextBlock_D03CA5023DA1257A9B127C36305ED053" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Schedule of Product Information [Table Text Block]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ScheduleOfProductInformationTableTextBlock" xlink:label="loc_us-gaap_ScheduleOfProductInformationTableTextBlock_D03CA5023DA1257A9B127C36305ED053" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfProductInformationTableTextBlock_D03CA5023DA1257A9B127C36305ED053" xlink:to="lab_us-gaap_ScheduleOfProductInformationTableTextBlock_D03CA5023DA1257A9B127C36305ED053" xlink:type="arc" />
    <link:label id="lab_us-gaap_ScheduleOfRevenuesFromExternalCustomersAndLongLivedAssetsByGeographicalAreasTableTextBlock_9B9C995B88F62BD1CA6D7C36305E1F52_terseLabel_en-US" xlink:label="lab_us-gaap_ScheduleOfRevenuesFromExternalCustomersAndLongLivedAssetsByGeographicalAreasTableTextBlock_9B9C995B88F62BD1CA6D7C36305E1F52" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Schedule of Geographic Information for Sales</link:label>
    <link:label id="lab_us-gaap_ScheduleOfRevenuesFromExternalCustomersAndLongLivedAssetsByGeographicalAreasTableTextBlock_9B9C995B88F62BD1CA6D7C36305E1F52_label_en-US" xlink:label="lab_us-gaap_ScheduleOfRevenuesFromExternalCustomersAndLongLivedAssetsByGeographicalAreasTableTextBlock_9B9C995B88F62BD1CA6D7C36305E1F52" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Schedule of Revenue from External Customers and Long-Lived Assets, by Geographical Areas [Table Text Block]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ScheduleOfRevenuesFromExternalCustomersAndLongLivedAssetsByGeographicalAreasTableTextBlock" xlink:label="loc_us-gaap_ScheduleOfRevenuesFromExternalCustomersAndLongLivedAssetsByGeographicalAreasTableTextBlock_9B9C995B88F62BD1CA6D7C36305E1F52" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfRevenuesFromExternalCustomersAndLongLivedAssetsByGeographicalAreasTableTextBlock_9B9C995B88F62BD1CA6D7C36305E1F52" xlink:to="lab_us-gaap_ScheduleOfRevenuesFromExternalCustomersAndLongLivedAssetsByGeographicalAreasTableTextBlock_9B9C995B88F62BD1CA6D7C36305E1F52" xlink:type="arc" />
    <link:label id="lab_us-gaap_ScheduleOfEntityWideDisclosureOnGeographicAreasLongLivedAssetsInIndividualForeignCountriesByCountryTextBlock_E0F53C6A77249327AE627C36305E3009_terseLabel_en-US" xlink:label="lab_us-gaap_ScheduleOfEntityWideDisclosureOnGeographicAreasLongLivedAssetsInIndividualForeignCountriesByCountryTextBlock_E0F53C6A77249327AE627C36305E3009" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Schedule of Geographic Information for Long-Lived Assets</link:label>
    <link:label id="lab_us-gaap_ScheduleOfEntityWideDisclosureOnGeographicAreasLongLivedAssetsInIndividualForeignCountriesByCountryTextBlock_E0F53C6A77249327AE627C36305E3009_label_en-US" xlink:label="lab_us-gaap_ScheduleOfEntityWideDisclosureOnGeographicAreasLongLivedAssetsInIndividualForeignCountriesByCountryTextBlock_E0F53C6A77249327AE627C36305E3009" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Schedule of Disclosure on Geographic Areas, Long-Lived Assets in Individual Foreign Countries by Country [Table Text Block]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ScheduleOfEntityWideDisclosureOnGeographicAreasLongLivedAssetsInIndividualForeignCountriesByCountryTextBlock" xlink:label="loc_us-gaap_ScheduleOfEntityWideDisclosureOnGeographicAreasLongLivedAssetsInIndividualForeignCountriesByCountryTextBlock_E0F53C6A77249327AE627C36305E3009" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfEntityWideDisclosureOnGeographicAreasLongLivedAssetsInIndividualForeignCountriesByCountryTextBlock_E0F53C6A77249327AE627C36305E3009" xlink:to="lab_us-gaap_ScheduleOfEntityWideDisclosureOnGeographicAreasLongLivedAssetsInIndividualForeignCountriesByCountryTextBlock_E0F53C6A77249327AE627C36305E3009" xlink:type="arc" />
    <link:label id="lab_us-gaap_RestructuringAndRelatedActivitiesAbstract_B4967135AB1B948DEC04E248CDC8BAC6_label_en-US" xlink:label="lab_us-gaap_RestructuringAndRelatedActivitiesAbstract_B4967135AB1B948DEC04E248CDC8BAC6" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Restructuring and Related Activities [Abstract]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RestructuringAndRelatedActivitiesAbstract" xlink:label="loc_us-gaap_RestructuringAndRelatedActivitiesAbstract_B4967135AB1B948DEC04E248CDC8BAC6" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RestructuringAndRelatedActivitiesAbstract_B4967135AB1B948DEC04E248CDC8BAC6" xlink:to="lab_us-gaap_RestructuringAndRelatedActivitiesAbstract_B4967135AB1B948DEC04E248CDC8BAC6" xlink:type="arc" />
    <link:label id="lab_us-gaap_ScheduleOfRestructuringAndRelatedCostsTextBlock_C09821AF141FAC5B0AEDE248CDC845B0_terseLabel_en-US" xlink:label="lab_us-gaap_ScheduleOfRestructuringAndRelatedCostsTextBlock_C09821AF141FAC5B0AEDE248CDC845B0" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Schedule of Restructuring and Other Charges</link:label>
    <link:label id="lab_us-gaap_ScheduleOfRestructuringAndRelatedCostsTextBlock_C09821AF141FAC5B0AEDE248CDC845B0_label_en-US" xlink:label="lab_us-gaap_ScheduleOfRestructuringAndRelatedCostsTextBlock_C09821AF141FAC5B0AEDE248CDC845B0" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Restructuring and Related Costs [Table Text Block]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ScheduleOfRestructuringAndRelatedCostsTextBlock" xlink:label="loc_us-gaap_ScheduleOfRestructuringAndRelatedCostsTextBlock_C09821AF141FAC5B0AEDE248CDC845B0" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfRestructuringAndRelatedCostsTextBlock_C09821AF141FAC5B0AEDE248CDC845B0" xlink:to="lab_us-gaap_ScheduleOfRestructuringAndRelatedCostsTextBlock_C09821AF141FAC5B0AEDE248CDC845B0" xlink:type="arc" />
    <link:label id="lab_arnc_ScheduleOfProFormaRestructuringChargesByReportableSegmentBeforeIncomeTaxTableTextBlock_E85DEAFDA6D011632BBCE248CDC8632C_terseLabel_en-US" xlink:label="lab_arnc_ScheduleOfProFormaRestructuringChargesByReportableSegmentBeforeIncomeTaxTableTextBlock_E85DEAFDA6D011632BBCE248CDC8632C" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Schedule of Restructuring and Other Charges by Reportable Segments, Pretax</link:label>
    <link:label id="lab_arnc_ScheduleOfProFormaRestructuringChargesByReportableSegmentBeforeIncomeTaxTableTextBlock_E85DEAFDA6D011632BBCE248CDC8632C_label_en-US" xlink:label="lab_arnc_ScheduleOfProFormaRestructuringChargesByReportableSegmentBeforeIncomeTaxTableTextBlock_E85DEAFDA6D011632BBCE248CDC8632C" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Schedule Of Pro Forma Restructuring Charges By Reportable Segment Before Income Tax [Table Text Block]</link:label>
    <link:label id="lab_arnc_ScheduleOfProFormaRestructuringChargesByReportableSegmentBeforeIncomeTaxTableTextBlock_E85DEAFDA6D011632BBCE248CDC8632C_documentation_en-US" xlink:label="lab_arnc_ScheduleOfProFormaRestructuringChargesByReportableSegmentBeforeIncomeTaxTableTextBlock_E85DEAFDA6D011632BBCE248CDC8632C" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Tabular disclosure of the entity restructuring charges before income tax by reportable segment had such charges been included in the entity's segment results.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_ScheduleOfProFormaRestructuringChargesByReportableSegmentBeforeIncomeTaxTableTextBlock" xlink:label="loc_arnc_ScheduleOfProFormaRestructuringChargesByReportableSegmentBeforeIncomeTaxTableTextBlock_E85DEAFDA6D011632BBCE248CDC8632C" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_ScheduleOfProFormaRestructuringChargesByReportableSegmentBeforeIncomeTaxTableTextBlock_E85DEAFDA6D011632BBCE248CDC8632C" xlink:to="lab_arnc_ScheduleOfProFormaRestructuringChargesByReportableSegmentBeforeIncomeTaxTableTextBlock_E85DEAFDA6D011632BBCE248CDC8632C" xlink:type="arc" />
    <link:label id="lab_us-gaap_IncomeTaxDisclosureTextBlock_5F60483E4827771E4C537C362EB81F77_terseLabel_en-US" xlink:label="lab_us-gaap_IncomeTaxDisclosureTextBlock_5F60483E4827771E4C537C362EB81F77" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Income Taxes</link:label>
    <link:label id="lab_us-gaap_IncomeTaxDisclosureTextBlock_5F60483E4827771E4C537C362EB81F77_label_en-US" xlink:label="lab_us-gaap_IncomeTaxDisclosureTextBlock_5F60483E4827771E4C537C362EB81F77" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Income Tax Disclosure [Text Block]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_IncomeTaxDisclosureTextBlock" xlink:label="loc_us-gaap_IncomeTaxDisclosureTextBlock_5F60483E4827771E4C537C362EB81F77" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncomeTaxDisclosureTextBlock_5F60483E4827771E4C537C362EB81F77" xlink:to="lab_us-gaap_IncomeTaxDisclosureTextBlock_5F60483E4827771E4C537C362EB81F77" xlink:type="arc" />
    <link:label id="lab_us-gaap_ReconciliationOfRevenueFromSegmentsToConsolidatedTable_DEADD198A43EF2E51552C968C31EB129_terseLabel_en-US" xlink:label="lab_us-gaap_ReconciliationOfRevenueFromSegmentsToConsolidatedTable_DEADD198A43EF2E51552C968C31EB129" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Reconciliation of Revenue from Segments to Consolidated [Table]</link:label>
    <link:label id="lab_us-gaap_ReconciliationOfRevenueFromSegmentsToConsolidatedTable_DEADD198A43EF2E51552C968C31EB129_label_en-US" xlink:label="lab_us-gaap_ReconciliationOfRevenueFromSegmentsToConsolidatedTable_DEADD198A43EF2E51552C968C31EB129" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Reconciliation of Revenue from Segments to Consolidated [Table]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ReconciliationOfRevenueFromSegmentsToConsolidatedTable" xlink:label="loc_us-gaap_ReconciliationOfRevenueFromSegmentsToConsolidatedTable_DEADD198A43EF2E51552C968C31EB129" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ReconciliationOfRevenueFromSegmentsToConsolidatedTable_DEADD198A43EF2E51552C968C31EB129" xlink:to="lab_us-gaap_ReconciliationOfRevenueFromSegmentsToConsolidatedTable_DEADD198A43EF2E51552C968C31EB129" xlink:type="arc" />
    <link:label id="lab_srt_ConsolidationItemsAxis_E3DAF30E4210486E4656C968C31FF2DD_terseLabel_en-US" xlink:label="lab_srt_ConsolidationItemsAxis_E3DAF30E4210486E4656C968C31FF2DD" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Consolidation Items [Axis]</link:label>
    <link:label id="lab_srt_ConsolidationItemsAxis_E3DAF30E4210486E4656C968C31FF2DD_label_en-US" xlink:label="lab_srt_ConsolidationItemsAxis_E3DAF30E4210486E4656C968C31FF2DD" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Consolidation Items [Axis]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_ConsolidationItemsAxis" xlink:label="loc_srt_ConsolidationItemsAxis_E3DAF30E4210486E4656C968C31FF2DD" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_srt_ConsolidationItemsAxis_E3DAF30E4210486E4656C968C31FF2DD" xlink:to="lab_srt_ConsolidationItemsAxis_E3DAF30E4210486E4656C968C31FF2DD" xlink:type="arc" />
    <link:label id="lab_srt_ConsolidationItemsDomain_7CE61C7F688D424E8C81C968C31F0534_terseLabel_en-US" xlink:label="lab_srt_ConsolidationItemsDomain_7CE61C7F688D424E8C81C968C31F0534" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Consolidation Items [Domain]</link:label>
    <link:label id="lab_srt_ConsolidationItemsDomain_7CE61C7F688D424E8C81C968C31F0534_label_en-US" xlink:label="lab_srt_ConsolidationItemsDomain_7CE61C7F688D424E8C81C968C31F0534" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Consolidation Items [Domain]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_ConsolidationItemsDomain" xlink:label="loc_srt_ConsolidationItemsDomain_7CE61C7F688D424E8C81C968C31F0534" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_srt_ConsolidationItemsDomain_7CE61C7F688D424E8C81C968C31F0534" xlink:to="lab_srt_ConsolidationItemsDomain_7CE61C7F688D424E8C81C968C31F0534" xlink:type="arc" />
    <link:label id="lab_us-gaap_OperatingSegmentsMember_8543E4935C09AF9911C5C968C31FAD30_terseLabel_en-US" xlink:label="lab_us-gaap_OperatingSegmentsMember_8543E4935C09AF9911C5C968C31FAD30" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Total segment sales</link:label>
    <link:label id="lab_us-gaap_OperatingSegmentsMember_8543E4935C09AF9911C5C968C31FAD30_label_en-US" xlink:label="lab_us-gaap_OperatingSegmentsMember_8543E4935C09AF9911C5C968C31FAD30" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Operating Segments [Member]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_OperatingSegmentsMember" xlink:label="loc_us-gaap_OperatingSegmentsMember_8543E4935C09AF9911C5C968C31FAD30" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OperatingSegmentsMember_8543E4935C09AF9911C5C968C31FAD30" xlink:to="lab_us-gaap_OperatingSegmentsMember_8543E4935C09AF9911C5C968C31FAD30" xlink:type="arc" />
    <link:label id="lab_us-gaap_IntersegmentEliminationMember_917C4FA658A516D7A637C968C320831C_verboseLabel_en-US" xlink:label="lab_us-gaap_IntersegmentEliminationMember_917C4FA658A516D7A637C968C320831C" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Elimination of intersegment sales</link:label>
    <link:label id="lab_us-gaap_IntersegmentEliminationMember_917C4FA658A516D7A637C968C320831C_label_en-US" xlink:label="lab_us-gaap_IntersegmentEliminationMember_917C4FA658A516D7A637C968C320831C" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Intersegment Eliminations [Member]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_IntersegmentEliminationMember" xlink:label="loc_us-gaap_IntersegmentEliminationMember_917C4FA658A516D7A637C968C320831C" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IntersegmentEliminationMember_917C4FA658A516D7A637C968C320831C" xlink:to="lab_us-gaap_IntersegmentEliminationMember_917C4FA658A516D7A637C968C320831C" xlink:type="arc" />
    <link:label id="lab_us-gaap_CorporateNonSegmentMember_DC6A8B387284ADFB9354C968C320A588_terseLabel_en-US" xlink:label="lab_us-gaap_CorporateNonSegmentMember_DC6A8B387284ADFB9354C968C320A588" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Corporate</link:label>
    <link:label id="lab_us-gaap_CorporateNonSegmentMember_DC6A8B387284ADFB9354C968C320A588_label_en-US" xlink:label="lab_us-gaap_CorporateNonSegmentMember_DC6A8B387284ADFB9354C968C320A588" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Corporate, Non-Segment [Member]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_CorporateNonSegmentMember" xlink:label="loc_us-gaap_CorporateNonSegmentMember_DC6A8B387284ADFB9354C968C320A588" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CorporateNonSegmentMember_DC6A8B387284ADFB9354C968C320A588" xlink:to="lab_us-gaap_CorporateNonSegmentMember_DC6A8B387284ADFB9354C968C320A588" xlink:type="arc" />
    <link:label id="lab_us-gaap_SegmentReportingRevenueReconcilingItemLineItems_BA63C7443E1E9683435CC968C320E09E_terseLabel_en-US" xlink:label="lab_us-gaap_SegmentReportingRevenueReconcilingItemLineItems_BA63C7443E1E9683435CC968C320E09E" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Segment Reporting, Revenue Reconciling Item [Line Items]</link:label>
    <link:label id="lab_us-gaap_SegmentReportingRevenueReconcilingItemLineItems_BA63C7443E1E9683435CC968C320E09E_label_en-US" xlink:label="lab_us-gaap_SegmentReportingRevenueReconcilingItemLineItems_BA63C7443E1E9683435CC968C320E09E" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Segment Reporting, Revenue Reconciling Item [Line Items]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_SegmentReportingRevenueReconcilingItemLineItems" xlink:label="loc_us-gaap_SegmentReportingRevenueReconcilingItemLineItems_BA63C7443E1E9683435CC968C320E09E" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SegmentReportingRevenueReconcilingItemLineItems_BA63C7443E1E9683435CC968C320E09E" xlink:to="lab_us-gaap_SegmentReportingRevenueReconcilingItemLineItems_BA63C7443E1E9683435CC968C320E09E" xlink:type="arc" />
    <link:label id="lab_us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_2D7C940397FBE79CD49CC9BED5C0D2EB_terseLabel_en-US" xlink:label="lab_us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_2D7C940397FBE79CD49CC9BED5C0D2EB" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Sales (B and C)</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax" xlink:label="loc_us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_2D7C940397FBE79CD49CC9BED5C0D2EB" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_2D7C940397FBE79CD49CC9BED5C0D2EB" xlink:to="lab_us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_2D7C940397FBE79CD49CC9BED5C0D2EB" xlink:type="arc" />
    <link:label id="lab_us-gaap_DefinedBenefitPlanExpectedReturnOnPlanAssets_C90568461E7FB2CFD8379F57209D438C_negatedLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanExpectedReturnOnPlanAssets_C90568461E7FB2CFD8379F57209D438C" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xml:lang="en-US">Expected return on plan assets</link:label>
    <link:label id="lab_us-gaap_DefinedBenefitPlanExpectedReturnOnPlanAssets_C90568461E7FB2CFD8379F57209D438C_label_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanExpectedReturnOnPlanAssets_C90568461E7FB2CFD8379F57209D438C" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Expected Return (Loss) on Plan Assets</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DefinedBenefitPlanExpectedReturnOnPlanAssets" xlink:label="loc_us-gaap_DefinedBenefitPlanExpectedReturnOnPlanAssets_C90568461E7FB2CFD8379F57209D438C" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanExpectedReturnOnPlanAssets_C90568461E7FB2CFD8379F57209D438C" xlink:to="lab_us-gaap_DefinedBenefitPlanExpectedReturnOnPlanAssets_C90568461E7FB2CFD8379F57209D438C" xlink:type="arc" />
    <link:label id="lab_us-gaap_DefinedBenefitPlanAmortizationOfGainsLosses_F61E7927F6979C479AEE9F57209D107F_negatedTerseLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanAmortizationOfGainsLosses_F61E7927F6979C479AEE9F57209D107F" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:type="resource" xml:lang="en-US">Recognized net actuarial loss</link:label>
    <link:label id="lab_us-gaap_DefinedBenefitPlanAmortizationOfGainsLosses_F61E7927F6979C479AEE9F57209D107F_label_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanAmortizationOfGainsLosses_F61E7927F6979C479AEE9F57209D107F" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Amortization of Gain (Loss)</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DefinedBenefitPlanAmortizationOfGainsLosses" xlink:label="loc_us-gaap_DefinedBenefitPlanAmortizationOfGainsLosses_F61E7927F6979C479AEE9F57209D107F" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanAmortizationOfGainsLosses_F61E7927F6979C479AEE9F57209D107F" xlink:to="lab_us-gaap_DefinedBenefitPlanAmortizationOfGainsLosses_F61E7927F6979C479AEE9F57209D107F" xlink:type="arc" />
    <link:label id="lab_us-gaap_DefinedBenefitPlanAmortizationOfPriorServiceCostCredit_2806E3418B6CC613EE9C9F57209D7CDB_terseLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanAmortizationOfPriorServiceCostCredit_2806E3418B6CC613EE9C9F57209D7CDB" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Amortization of prior service cost (benefit)</link:label>
    <link:label id="lab_us-gaap_DefinedBenefitPlanAmortizationOfPriorServiceCostCredit_2806E3418B6CC613EE9C9F57209D7CDB_label_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanAmortizationOfPriorServiceCostCredit_2806E3418B6CC613EE9C9F57209D7CDB" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Amortization of Prior Service Cost (Credit)</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DefinedBenefitPlanAmortizationOfPriorServiceCostCredit" xlink:label="loc_us-gaap_DefinedBenefitPlanAmortizationOfPriorServiceCostCredit_2806E3418B6CC613EE9C9F57209D7CDB" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanAmortizationOfPriorServiceCostCredit_2806E3418B6CC613EE9C9F57209D7CDB" xlink:to="lab_us-gaap_DefinedBenefitPlanAmortizationOfPriorServiceCostCredit_2806E3418B6CC613EE9C9F57209D7CDB" xlink:type="arc" />
    <link:label id="lab_us-gaap_DefinedBenefitPlanRecognizedNetGainLossDueToSettlements1_B35FB3CD5C435A9E6E869F57209DC0E7_negatedLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanRecognizedNetGainLossDueToSettlements1_B35FB3CD5C435A9E6E869F57209DC0E7" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xml:lang="en-US">Settlements</link:label>
    <link:label id="lab_us-gaap_DefinedBenefitPlanRecognizedNetGainLossDueToSettlements1_B35FB3CD5C435A9E6E869F57209DC0E7_label_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanRecognizedNetGainLossDueToSettlements1_B35FB3CD5C435A9E6E869F57209DC0E7" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Net Periodic Benefit Cost (Credit), Gain (Loss) Due to Settlement</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DefinedBenefitPlanRecognizedNetGainLossDueToSettlements1" xlink:label="loc_us-gaap_DefinedBenefitPlanRecognizedNetGainLossDueToSettlements1_B35FB3CD5C435A9E6E869F57209DC0E7" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanRecognizedNetGainLossDueToSettlements1_B35FB3CD5C435A9E6E869F57209DC0E7" xlink:to="lab_us-gaap_DefinedBenefitPlanRecognizedNetGainLossDueToSettlements1_B35FB3CD5C435A9E6E869F57209DC0E7" xlink:type="arc" />
    <link:label id="lab_us-gaap_DefinedBenefitPlanRecognizedNetGainLossDueToCurtailments_F11E9C2AFE9D288F07799F57209D7F55_negatedLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanRecognizedNetGainLossDueToCurtailments_F11E9C2AFE9D288F07799F57209D7F55" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xml:lang="en-US">Curtailments</link:label>
    <link:label id="lab_us-gaap_DefinedBenefitPlanRecognizedNetGainLossDueToCurtailments_F11E9C2AFE9D288F07799F57209D7F55_label_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanRecognizedNetGainLossDueToCurtailments_F11E9C2AFE9D288F07799F57209D7F55" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Net Periodic Benefit Cost (Credit), Gain (Loss) Due to Curtailment</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DefinedBenefitPlanRecognizedNetGainLossDueToCurtailments" xlink:label="loc_us-gaap_DefinedBenefitPlanRecognizedNetGainLossDueToCurtailments_F11E9C2AFE9D288F07799F57209D7F55" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanRecognizedNetGainLossDueToCurtailments_F11E9C2AFE9D288F07799F57209D7F55" xlink:to="lab_us-gaap_DefinedBenefitPlanRecognizedNetGainLossDueToCurtailments_F11E9C2AFE9D288F07799F57209D7F55" xlink:type="arc" />
    <link:label id="lab_us-gaap_DefinedBenefitPlanCostOfProvidingSpecialOrContractualTerminationBenefitRecognizedDuringPeriod_06FABD805EDBE961FFDB9F57209D55E3_terseLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanCostOfProvidingSpecialOrContractualTerminationBenefitRecognizedDuringPeriod_06FABD805EDBE961FFDB9F57209D55E3" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Special termination benefits</link:label>
    <link:label id="lab_us-gaap_DefinedBenefitPlanCostOfProvidingSpecialOrContractualTerminationBenefitRecognizedDuringPeriod_06FABD805EDBE961FFDB9F57209D55E3_label_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanCostOfProvidingSpecialOrContractualTerminationBenefitRecognizedDuringPeriod_06FABD805EDBE961FFDB9F57209D55E3" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Cost of Providing Special and Contractual Termination Benefits</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DefinedBenefitPlanCostOfProvidingSpecialOrContractualTerminationBenefitRecognizedDuringPeriod" xlink:label="loc_us-gaap_DefinedBenefitPlanCostOfProvidingSpecialOrContractualTerminationBenefitRecognizedDuringPeriod_06FABD805EDBE961FFDB9F57209D55E3" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanCostOfProvidingSpecialOrContractualTerminationBenefitRecognizedDuringPeriod_06FABD805EDBE961FFDB9F57209D55E3" xlink:to="lab_us-gaap_DefinedBenefitPlanCostOfProvidingSpecialOrContractualTerminationBenefitRecognizedDuringPeriod_06FABD805EDBE961FFDB9F57209D55E3" xlink:type="arc" />
    <link:label id="lab_us-gaap_DefinedBenefitPlanNetPeriodicBenefitCost_F70F4EB6F83DA0CC5BB69F57209D043D_totalLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanNetPeriodicBenefitCost_F70F4EB6F83DA0CC5BB69F57209D043D" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Net periodic benefit cost</link:label>
    <link:label id="lab_us-gaap_DefinedBenefitPlanNetPeriodicBenefitCost_F70F4EB6F83DA0CC5BB69F57209D043D_label_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanNetPeriodicBenefitCost_F70F4EB6F83DA0CC5BB69F57209D043D" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Net Periodic Benefit Cost (Credit)</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DefinedBenefitPlanNetPeriodicBenefitCost" xlink:label="loc_us-gaap_DefinedBenefitPlanNetPeriodicBenefitCost_F70F4EB6F83DA0CC5BB69F57209D043D" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanNetPeriodicBenefitCost_F70F4EB6F83DA0CC5BB69F57209D043D" xlink:to="lab_us-gaap_DefinedBenefitPlanNetPeriodicBenefitCost_F70F4EB6F83DA0CC5BB69F57209D043D" xlink:type="arc" />
    <link:label id="lab_arnc_DefinedBenefitPlanNetPeriodicBenefitCostDiscontinuedOperations_FFFBD9C2B671858CD8B79F57209D11A6_negatedTerseLabel_en-US" xlink:label="lab_arnc_DefinedBenefitPlanNetPeriodicBenefitCostDiscontinuedOperations_FFFBD9C2B671858CD8B79F57209D11A6" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:type="resource" xml:lang="en-US">Discontinued operations</link:label>
    <link:label id="lab_arnc_DefinedBenefitPlanNetPeriodicBenefitCostDiscontinuedOperations_FFFBD9C2B671858CD8B79F57209D11A6_label_en-US" xlink:label="lab_arnc_DefinedBenefitPlanNetPeriodicBenefitCostDiscontinuedOperations_FFFBD9C2B671858CD8B79F57209D11A6" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan Net Periodic Benefit Cost Discontinued Operations</link:label>
    <link:label id="lab_arnc_DefinedBenefitPlanNetPeriodicBenefitCostDiscontinuedOperations_FFFBD9C2B671858CD8B79F57209D11A6_documentation_en-US" xlink:label="lab_arnc_DefinedBenefitPlanNetPeriodicBenefitCostDiscontinuedOperations_FFFBD9C2B671858CD8B79F57209D11A6" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Defined benefit plan net periodic benefit cost discontinued operations.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_DefinedBenefitPlanNetPeriodicBenefitCostDiscontinuedOperations" xlink:label="loc_arnc_DefinedBenefitPlanNetPeriodicBenefitCostDiscontinuedOperations_FFFBD9C2B671858CD8B79F57209D11A6" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_DefinedBenefitPlanNetPeriodicBenefitCostDiscontinuedOperations_FFFBD9C2B671858CD8B79F57209D11A6" xlink:to="lab_arnc_DefinedBenefitPlanNetPeriodicBenefitCostDiscontinuedOperations_FFFBD9C2B671858CD8B79F57209D11A6" xlink:type="arc" />
    <link:label id="lab_arnc_DefinedBenefitPlanNetPeriodicBenefitCostContinuedOperation_B2D664C02CC3BBF052A69F57209DBCE5_totalLabel_en-US" xlink:label="lab_arnc_DefinedBenefitPlanNetPeriodicBenefitCostContinuedOperation_B2D664C02CC3BBF052A69F57209DBCE5" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Net amount recognized in Statement of Consolidated Operations</link:label>
    <link:label id="lab_arnc_DefinedBenefitPlanNetPeriodicBenefitCostContinuedOperation_B2D664C02CC3BBF052A69F57209DBCE5_label_en-US" xlink:label="lab_arnc_DefinedBenefitPlanNetPeriodicBenefitCostContinuedOperation_B2D664C02CC3BBF052A69F57209DBCE5" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan Net Periodic Benefit Cost Continued Operation</link:label>
    <link:label id="lab_arnc_DefinedBenefitPlanNetPeriodicBenefitCostContinuedOperation_B2D664C02CC3BBF052A69F57209DBCE5_documentation_en-US" xlink:label="lab_arnc_DefinedBenefitPlanNetPeriodicBenefitCostContinuedOperation_B2D664C02CC3BBF052A69F57209DBCE5" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Defined benefit plan net periodic benefit cost continued operation.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_DefinedBenefitPlanNetPeriodicBenefitCostContinuedOperation" xlink:label="loc_arnc_DefinedBenefitPlanNetPeriodicBenefitCostContinuedOperation_B2D664C02CC3BBF052A69F57209DBCE5" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_DefinedBenefitPlanNetPeriodicBenefitCostContinuedOperation_B2D664C02CC3BBF052A69F57209DBCE5" xlink:to="lab_arnc_DefinedBenefitPlanNetPeriodicBenefitCostContinuedOperation_B2D664C02CC3BBF052A69F57209DBCE5" xlink:type="arc" />
    <link:label id="lab_us-gaap_DefinedBenefitPlanPrescriptionDrugBenefitAccumulatedPostretirementBenefitObligationDecreaseForSubsidy_60759125AF2F84FCE3549F57209DEE38_terseLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanPrescriptionDrugBenefitAccumulatedPostretirementBenefitObligationDecreaseForSubsidy_60759125AF2F84FCE3549F57209DEE38" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Decrease in net periodic benefit cost for the recognition of the federal subsidy awarded under Medicare Part D</link:label>
    <link:label id="lab_us-gaap_DefinedBenefitPlanPrescriptionDrugBenefitAccumulatedPostretirementBenefitObligationDecreaseForSubsidy_60759125AF2F84FCE3549F57209DEE38_label_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanPrescriptionDrugBenefitAccumulatedPostretirementBenefitObligationDecreaseForSubsidy_60759125AF2F84FCE3549F57209DEE38" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Prescription Drug Benefit, Accumulated Postretirement Benefit Obligation, Decrease for Subsidy</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DefinedBenefitPlanPrescriptionDrugBenefitAccumulatedPostretirementBenefitObligationDecreaseForSubsidy" xlink:label="loc_us-gaap_DefinedBenefitPlanPrescriptionDrugBenefitAccumulatedPostretirementBenefitObligationDecreaseForSubsidy_60759125AF2F84FCE3549F57209DEE38" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanPrescriptionDrugBenefitAccumulatedPostretirementBenefitObligationDecreaseForSubsidy_60759125AF2F84FCE3549F57209DEE38" xlink:to="lab_us-gaap_DefinedBenefitPlanPrescriptionDrugBenefitAccumulatedPostretirementBenefitObligationDecreaseForSubsidy_60759125AF2F84FCE3549F57209DEE38" xlink:type="arc" />
    <link:label id="lab_us-gaap_StatementOfFinancialPositionAbstract_D9545935FCBC884F7177BA4BBF5BED22_label_en-US" xlink:label="lab_us-gaap_StatementOfFinancialPositionAbstract_D9545935FCBC884F7177BA4BBF5BED22" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Statement of Financial Position [Abstract]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_StatementOfFinancialPositionAbstract" xlink:label="loc_us-gaap_StatementOfFinancialPositionAbstract_D9545935FCBC884F7177BA4BBF5BED22" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_StatementOfFinancialPositionAbstract_D9545935FCBC884F7177BA4BBF5BED22" xlink:to="lab_us-gaap_StatementOfFinancialPositionAbstract_D9545935FCBC884F7177BA4BBF5BED22" xlink:type="arc" />
    <link:label id="lab_us-gaap_AssetsAbstract_D588C62DB2B0BA1FACA7BA4BBF5B59DB_terseLabel_en-US" xlink:label="lab_us-gaap_AssetsAbstract_D588C62DB2B0BA1FACA7BA4BBF5B59DB" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Assets</link:label>
    <link:label id="lab_us-gaap_AssetsAbstract_D588C62DB2B0BA1FACA7BA4BBF5B59DB_label_en-US" xlink:label="lab_us-gaap_AssetsAbstract_D588C62DB2B0BA1FACA7BA4BBF5B59DB" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Assets [Abstract]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AssetsAbstract" xlink:label="loc_us-gaap_AssetsAbstract_D588C62DB2B0BA1FACA7BA4BBF5B59DB" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AssetsAbstract_D588C62DB2B0BA1FACA7BA4BBF5B59DB" xlink:to="lab_us-gaap_AssetsAbstract_D588C62DB2B0BA1FACA7BA4BBF5B59DB" xlink:type="arc" />
    <link:label id="lab_us-gaap_AssetsCurrentAbstract_B9069E6EAEE25FA62A97BA4BBF5B7EEC_terseLabel_en-US" xlink:label="lab_us-gaap_AssetsCurrentAbstract_B9069E6EAEE25FA62A97BA4BBF5B7EEC" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Current assets:</link:label>
    <link:label id="lab_us-gaap_AssetsCurrentAbstract_B9069E6EAEE25FA62A97BA4BBF5B7EEC_label_en-US" xlink:label="lab_us-gaap_AssetsCurrentAbstract_B9069E6EAEE25FA62A97BA4BBF5B7EEC" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Assets, Current [Abstract]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AssetsCurrentAbstract" xlink:label="loc_us-gaap_AssetsCurrentAbstract_B9069E6EAEE25FA62A97BA4BBF5B7EEC" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AssetsCurrentAbstract_B9069E6EAEE25FA62A97BA4BBF5B7EEC" xlink:to="lab_us-gaap_AssetsCurrentAbstract_B9069E6EAEE25FA62A97BA4BBF5B7EEC" xlink:type="arc" />
    <link:label id="lab_us-gaap_CashAndCashEquivalentsAtCarryingValue_A0505362F254C3C3467BBA4BBF5BF579_verboseLabel_en-US" xlink:label="lab_us-gaap_CashAndCashEquivalentsAtCarryingValue_A0505362F254C3C3467BBA4BBF5BF579" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Cash and cash equivalents</link:label>
    <link:label id="lab_us-gaap_CashAndCashEquivalentsAtCarryingValue_A0505362F254C3C3467BBA4BBF5BF579_label_en-US" xlink:label="lab_us-gaap_CashAndCashEquivalentsAtCarryingValue_A0505362F254C3C3467BBA4BBF5BF579" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Cash and Cash Equivalents, at Carrying Value</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_CashAndCashEquivalentsAtCarryingValue" xlink:label="loc_us-gaap_CashAndCashEquivalentsAtCarryingValue_A0505362F254C3C3467BBA4BBF5BF579" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CashAndCashEquivalentsAtCarryingValue_A0505362F254C3C3467BBA4BBF5BF579" xlink:to="lab_us-gaap_CashAndCashEquivalentsAtCarryingValue_A0505362F254C3C3467BBA4BBF5BF579" xlink:type="arc" />
    <link:label id="lab_us-gaap_AccountsReceivableNetCurrent_2E7353ACAC8BFBB76616BA4BBF5B7386_terseLabel_en-US" xlink:label="lab_us-gaap_AccountsReceivableNetCurrent_2E7353ACAC8BFBB76616BA4BBF5B7386" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Receivables from customers, less allowances of $4 in 2018 and $8 in 2017 (L)</link:label>
    <link:label id="lab_us-gaap_AccountsReceivableNetCurrent_2E7353ACAC8BFBB76616BA4BBF5B7386_label_en-US" xlink:label="lab_us-gaap_AccountsReceivableNetCurrent_2E7353ACAC8BFBB76616BA4BBF5B7386" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Accounts Receivable, Net, Current</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AccountsReceivableNetCurrent" xlink:label="loc_us-gaap_AccountsReceivableNetCurrent_2E7353ACAC8BFBB76616BA4BBF5B7386" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AccountsReceivableNetCurrent_2E7353ACAC8BFBB76616BA4BBF5B7386" xlink:to="lab_us-gaap_AccountsReceivableNetCurrent_2E7353ACAC8BFBB76616BA4BBF5B7386" xlink:type="arc" />
    <link:label id="lab_us-gaap_OtherReceivablesNetCurrent_08BAA3A683CC1FB8671DBA4BBF5B440E_terseLabel_en-US" xlink:label="lab_us-gaap_OtherReceivablesNetCurrent_08BAA3A683CC1FB8671DBA4BBF5B440E" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Other receivables (L)</link:label>
    <link:label id="lab_us-gaap_OtherReceivablesNetCurrent_08BAA3A683CC1FB8671DBA4BBF5B440E_label_en-US" xlink:label="lab_us-gaap_OtherReceivablesNetCurrent_08BAA3A683CC1FB8671DBA4BBF5B440E" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Other Receivables, Net, Current</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_OtherReceivablesNetCurrent" xlink:label="loc_us-gaap_OtherReceivablesNetCurrent_08BAA3A683CC1FB8671DBA4BBF5B440E" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OtherReceivablesNetCurrent_08BAA3A683CC1FB8671DBA4BBF5B440E" xlink:to="lab_us-gaap_OtherReceivablesNetCurrent_08BAA3A683CC1FB8671DBA4BBF5B440E" xlink:type="arc" />
    <link:label id="lab_us-gaap_InventoryNet_4B40488232524F310334BA4BBF5BE386_terseLabel_en-US" xlink:label="lab_us-gaap_InventoryNet_4B40488232524F310334BA4BBF5BE386" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Inventories (M)</link:label>
    <link:label id="lab_us-gaap_InventoryNet_4B40488232524F310334BA4BBF5BE386_label_en-US" xlink:label="lab_us-gaap_InventoryNet_4B40488232524F310334BA4BBF5BE386" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Inventory, Net</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_InventoryNet" xlink:label="loc_us-gaap_InventoryNet_4B40488232524F310334BA4BBF5BE386" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_InventoryNet_4B40488232524F310334BA4BBF5BE386" xlink:to="lab_us-gaap_InventoryNet_4B40488232524F310334BA4BBF5BE386" xlink:type="arc" />
    <link:label id="lab_us-gaap_PrepaidExpenseAndOtherAssetsCurrent_706002D6224F3B90365CBA4BBF5BB918_terseLabel_en-US" xlink:label="lab_us-gaap_PrepaidExpenseAndOtherAssetsCurrent_706002D6224F3B90365CBA4BBF5BB918" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Prepaid expenses and other current assets</link:label>
    <link:label id="lab_us-gaap_PrepaidExpenseAndOtherAssetsCurrent_706002D6224F3B90365CBA4BBF5BB918_label_en-US" xlink:label="lab_us-gaap_PrepaidExpenseAndOtherAssetsCurrent_706002D6224F3B90365CBA4BBF5BB918" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Prepaid Expense and Other Assets, Current</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PrepaidExpenseAndOtherAssetsCurrent" xlink:label="loc_us-gaap_PrepaidExpenseAndOtherAssetsCurrent_706002D6224F3B90365CBA4BBF5BB918" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PrepaidExpenseAndOtherAssetsCurrent_706002D6224F3B90365CBA4BBF5BB918" xlink:to="lab_us-gaap_PrepaidExpenseAndOtherAssetsCurrent_706002D6224F3B90365CBA4BBF5BB918" xlink:type="arc" />
    <link:label id="lab_us-gaap_AssetsCurrent_648E03E37A406FAC8FD4BA4BBF5B0CA0_totalLabel_en-US" xlink:label="lab_us-gaap_AssetsCurrent_648E03E37A406FAC8FD4BA4BBF5B0CA0" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Total current assets</link:label>
    <link:label id="lab_us-gaap_AssetsCurrent_648E03E37A406FAC8FD4BA4BBF5B0CA0_label_en-US" xlink:label="lab_us-gaap_AssetsCurrent_648E03E37A406FAC8FD4BA4BBF5B0CA0" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Assets, Current</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AssetsCurrent" xlink:label="loc_us-gaap_AssetsCurrent_648E03E37A406FAC8FD4BA4BBF5B0CA0" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AssetsCurrent_648E03E37A406FAC8FD4BA4BBF5B0CA0" xlink:to="lab_us-gaap_AssetsCurrent_648E03E37A406FAC8FD4BA4BBF5B0CA0" xlink:type="arc" />
    <link:label id="lab_us-gaap_PropertyPlantAndEquipmentNet_11A73ABA0949E315C2E4BA4BBF5BC7CB_positiveLabel_en-US" xlink:label="lab_us-gaap_PropertyPlantAndEquipmentNet_11A73ABA0949E315C2E4BA4BBF5BC7CB" xlink:role="http://www.xbrl.org/2003/role/positiveLabel" xlink:type="resource" xml:lang="en-US">Properties, plants, and equipment, net (N)</link:label>
    <link:label id="lab_us-gaap_PropertyPlantAndEquipmentNet_11A73ABA0949E315C2E4BA4BBF5BC7CB_label_en-US" xlink:label="lab_us-gaap_PropertyPlantAndEquipmentNet_11A73ABA0949E315C2E4BA4BBF5BC7CB" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Property, Plant and Equipment, Net</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PropertyPlantAndEquipmentNet" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentNet_11A73ABA0949E315C2E4BA4BBF5BC7CB" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentNet_11A73ABA0949E315C2E4BA4BBF5BC7CB" xlink:to="lab_us-gaap_PropertyPlantAndEquipmentNet_11A73ABA0949E315C2E4BA4BBF5BC7CB" xlink:type="arc" />
    <link:label id="lab_us-gaap_Goodwill_0E1658696D8325627191BA4BBF5B6F03_positiveLabel_en-US" xlink:label="lab_us-gaap_Goodwill_0E1658696D8325627191BA4BBF5B6F03" xlink:role="http://www.xbrl.org/2003/role/positiveLabel" xlink:type="resource" xml:lang="en-US">Goodwill (A and O)</link:label>
    <link:label id="lab_us-gaap_Goodwill_0E1658696D8325627191BA4BBF5B6F03_label_en-US" xlink:label="lab_us-gaap_Goodwill_0E1658696D8325627191BA4BBF5B6F03" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Goodwill</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_Goodwill" xlink:label="loc_us-gaap_Goodwill_0E1658696D8325627191BA4BBF5B6F03" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_Goodwill_0E1658696D8325627191BA4BBF5B6F03" xlink:to="lab_us-gaap_Goodwill_0E1658696D8325627191BA4BBF5B6F03" xlink:type="arc" />
    <link:label id="lab_us-gaap_DeferredIncomeTaxAssetsNet_E2E11BD6B886089D79D3BA4BBF5BCBE3_terseLabel_en-US" xlink:label="lab_us-gaap_DeferredIncomeTaxAssetsNet_E2E11BD6B886089D79D3BA4BBF5BCBE3" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Deferred income taxes (H)</link:label>
    <link:label id="lab_us-gaap_DeferredIncomeTaxAssetsNet_E2E11BD6B886089D79D3BA4BBF5BCBE3_label_en-US" xlink:label="lab_us-gaap_DeferredIncomeTaxAssetsNet_E2E11BD6B886089D79D3BA4BBF5BCBE3" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Deferred Income Tax Assets, Net</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DeferredIncomeTaxAssetsNet" xlink:label="loc_us-gaap_DeferredIncomeTaxAssetsNet_E2E11BD6B886089D79D3BA4BBF5BCBE3" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DeferredIncomeTaxAssetsNet_E2E11BD6B886089D79D3BA4BBF5BCBE3" xlink:to="lab_us-gaap_DeferredIncomeTaxAssetsNet_E2E11BD6B886089D79D3BA4BBF5BCBE3" xlink:type="arc" />
    <link:label id="lab_us-gaap_IntangibleAssetsNetExcludingGoodwill_A5BF8C9AA4B491F4A7C0BA4BBF5B32B4_terseLabel_en-US" xlink:label="lab_us-gaap_IntangibleAssetsNetExcludingGoodwill_A5BF8C9AA4B491F4A7C0BA4BBF5B32B4" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Intangibles, net (O)</link:label>
    <link:label id="lab_us-gaap_IntangibleAssetsNetExcludingGoodwill_A5BF8C9AA4B491F4A7C0BA4BBF5B32B4_label_en-US" xlink:label="lab_us-gaap_IntangibleAssetsNetExcludingGoodwill_A5BF8C9AA4B491F4A7C0BA4BBF5B32B4" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Intangible Assets, Net (Excluding Goodwill)</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_IntangibleAssetsNetExcludingGoodwill" xlink:label="loc_us-gaap_IntangibleAssetsNetExcludingGoodwill_A5BF8C9AA4B491F4A7C0BA4BBF5B32B4" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IntangibleAssetsNetExcludingGoodwill_A5BF8C9AA4B491F4A7C0BA4BBF5B32B4" xlink:to="lab_us-gaap_IntangibleAssetsNetExcludingGoodwill_A5BF8C9AA4B491F4A7C0BA4BBF5B32B4" xlink:type="arc" />
    <link:label id="lab_us-gaap_OtherAssetsNoncurrent_5752C086D77F14F72657BA4BBF5B264B_terseLabel_en-US" xlink:label="lab_us-gaap_OtherAssetsNoncurrent_5752C086D77F14F72657BA4BBF5B264B" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Other noncurrent assets</link:label>
    <link:label id="lab_us-gaap_OtherAssetsNoncurrent_5752C086D77F14F72657BA4BBF5B264B_label_en-US" xlink:label="lab_us-gaap_OtherAssetsNoncurrent_5752C086D77F14F72657BA4BBF5B264B" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Other Assets, Noncurrent</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_OtherAssetsNoncurrent" xlink:label="loc_us-gaap_OtherAssetsNoncurrent_5752C086D77F14F72657BA4BBF5B264B" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OtherAssetsNoncurrent_5752C086D77F14F72657BA4BBF5B264B" xlink:to="lab_us-gaap_OtherAssetsNoncurrent_5752C086D77F14F72657BA4BBF5B264B" xlink:type="arc" />
    <link:label id="lab_us-gaap_Assets_1E0FFC2E6C0377189B4FBA4BBF5B5EBE_totalLabel_en-US" xlink:label="lab_us-gaap_Assets_1E0FFC2E6C0377189B4FBA4BBF5B5EBE" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Total assets</link:label>
    <link:label id="lab_us-gaap_Assets_1E0FFC2E6C0377189B4FBA4BBF5B5EBE_label_en-US" xlink:label="lab_us-gaap_Assets_1E0FFC2E6C0377189B4FBA4BBF5B5EBE" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Assets</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_Assets" xlink:label="loc_us-gaap_Assets_1E0FFC2E6C0377189B4FBA4BBF5B5EBE" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_Assets_1E0FFC2E6C0377189B4FBA4BBF5B5EBE" xlink:to="lab_us-gaap_Assets_1E0FFC2E6C0377189B4FBA4BBF5B5EBE" xlink:type="arc" />
    <link:label id="lab_us-gaap_LiabilitiesAbstract_8776C181CDC8496727C1BA4BBF5BFFAD_terseLabel_en-US" xlink:label="lab_us-gaap_LiabilitiesAbstract_8776C181CDC8496727C1BA4BBF5BFFAD" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Liabilities</link:label>
    <link:label id="lab_us-gaap_LiabilitiesAbstract_8776C181CDC8496727C1BA4BBF5BFFAD_label_en-US" xlink:label="lab_us-gaap_LiabilitiesAbstract_8776C181CDC8496727C1BA4BBF5BFFAD" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Liabilities [Abstract]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_LiabilitiesAbstract" xlink:label="loc_us-gaap_LiabilitiesAbstract_8776C181CDC8496727C1BA4BBF5BFFAD" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LiabilitiesAbstract_8776C181CDC8496727C1BA4BBF5BFFAD" xlink:to="lab_us-gaap_LiabilitiesAbstract_8776C181CDC8496727C1BA4BBF5BFFAD" xlink:type="arc" />
    <link:label id="lab_us-gaap_LiabilitiesCurrentAbstract_4E76839D3C21A12E0A7DBA4BBF5BB8E6_terseLabel_en-US" xlink:label="lab_us-gaap_LiabilitiesCurrentAbstract_4E76839D3C21A12E0A7DBA4BBF5BB8E6" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Current liabilities:</link:label>
    <link:label id="lab_us-gaap_LiabilitiesCurrentAbstract_4E76839D3C21A12E0A7DBA4BBF5BB8E6_label_en-US" xlink:label="lab_us-gaap_LiabilitiesCurrentAbstract_4E76839D3C21A12E0A7DBA4BBF5BB8E6" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Liabilities, Current [Abstract]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_LiabilitiesCurrentAbstract" xlink:label="loc_us-gaap_LiabilitiesCurrentAbstract_4E76839D3C21A12E0A7DBA4BBF5BB8E6" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LiabilitiesCurrentAbstract_4E76839D3C21A12E0A7DBA4BBF5BB8E6" xlink:to="lab_us-gaap_LiabilitiesCurrentAbstract_4E76839D3C21A12E0A7DBA4BBF5BB8E6" xlink:type="arc" />
    <link:label id="lab_us-gaap_AccountsPayableCurrent_1179AE647F578D4621C8BA4BBF5B1ACF_terseLabel_en-US" xlink:label="lab_us-gaap_AccountsPayableCurrent_1179AE647F578D4621C8BA4BBF5B1ACF" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Accounts payable, trade</link:label>
    <link:label id="lab_us-gaap_AccountsPayableCurrent_1179AE647F578D4621C8BA4BBF5B1ACF_label_en-US" xlink:label="lab_us-gaap_AccountsPayableCurrent_1179AE647F578D4621C8BA4BBF5B1ACF" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Accounts Payable, Current</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AccountsPayableCurrent" xlink:label="loc_us-gaap_AccountsPayableCurrent_1179AE647F578D4621C8BA4BBF5B1ACF" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AccountsPayableCurrent_1179AE647F578D4621C8BA4BBF5B1ACF" xlink:to="lab_us-gaap_AccountsPayableCurrent_1179AE647F578D4621C8BA4BBF5B1ACF" xlink:type="arc" />
    <link:label id="lab_us-gaap_EmployeeRelatedLiabilitiesCurrent_5F4B08F541B83B6A1D3BBA4BBF5BE1A2_terseLabel_en-US" xlink:label="lab_us-gaap_EmployeeRelatedLiabilitiesCurrent_5F4B08F541B83B6A1D3BBA4BBF5BE1A2" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Accrued compensation and retirement costs</link:label>
    <link:label id="lab_us-gaap_EmployeeRelatedLiabilitiesCurrent_5F4B08F541B83B6A1D3BBA4BBF5BE1A2_label_en-US" xlink:label="lab_us-gaap_EmployeeRelatedLiabilitiesCurrent_5F4B08F541B83B6A1D3BBA4BBF5BE1A2" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Employee-related Liabilities, Current</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_EmployeeRelatedLiabilitiesCurrent" xlink:label="loc_us-gaap_EmployeeRelatedLiabilitiesCurrent_5F4B08F541B83B6A1D3BBA4BBF5BE1A2" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_EmployeeRelatedLiabilitiesCurrent_5F4B08F541B83B6A1D3BBA4BBF5BE1A2" xlink:to="lab_us-gaap_EmployeeRelatedLiabilitiesCurrent_5F4B08F541B83B6A1D3BBA4BBF5BE1A2" xlink:type="arc" />
    <link:label id="lab_us-gaap_TaxesPayableCurrent_896C5DD93EB0B59B44AFBA4BBF5F1FFD_terseLabel_en-US" xlink:label="lab_us-gaap_TaxesPayableCurrent_896C5DD93EB0B59B44AFBA4BBF5F1FFD" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Taxes, including income taxes</link:label>
    <link:label id="lab_us-gaap_TaxesPayableCurrent_896C5DD93EB0B59B44AFBA4BBF5F1FFD_label_en-US" xlink:label="lab_us-gaap_TaxesPayableCurrent_896C5DD93EB0B59B44AFBA4BBF5F1FFD" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Taxes Payable, Current</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_TaxesPayableCurrent" xlink:label="loc_us-gaap_TaxesPayableCurrent_896C5DD93EB0B59B44AFBA4BBF5F1FFD" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_TaxesPayableCurrent_896C5DD93EB0B59B44AFBA4BBF5F1FFD" xlink:to="lab_us-gaap_TaxesPayableCurrent_896C5DD93EB0B59B44AFBA4BBF5F1FFD" xlink:type="arc" />
    <link:label id="lab_us-gaap_InterestPayableCurrent_B138C9CBCB1BB206792FBA4BBF5F2FAA_terseLabel_en-US" xlink:label="lab_us-gaap_InterestPayableCurrent_B138C9CBCB1BB206792FBA4BBF5F2FAA" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Accrued interest payable</link:label>
    <link:label id="lab_us-gaap_InterestPayableCurrent_B138C9CBCB1BB206792FBA4BBF5F2FAA_label_en-US" xlink:label="lab_us-gaap_InterestPayableCurrent_B138C9CBCB1BB206792FBA4BBF5F2FAA" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Interest Payable, Current</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_InterestPayableCurrent" xlink:label="loc_us-gaap_InterestPayableCurrent_B138C9CBCB1BB206792FBA4BBF5F2FAA" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_InterestPayableCurrent_B138C9CBCB1BB206792FBA4BBF5F2FAA" xlink:to="lab_us-gaap_InterestPayableCurrent_B138C9CBCB1BB206792FBA4BBF5F2FAA" xlink:type="arc" />
    <link:label id="lab_us-gaap_OtherLiabilitiesCurrent_6B3A854CA8BC8DBAB903BA4BBF5FC303_terseLabel_en-US" xlink:label="lab_us-gaap_OtherLiabilitiesCurrent_6B3A854CA8BC8DBAB903BA4BBF5FC303" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Other current liabilities</link:label>
    <link:label id="lab_us-gaap_OtherLiabilitiesCurrent_6B3A854CA8BC8DBAB903BA4BBF5FC303_label_en-US" xlink:label="lab_us-gaap_OtherLiabilitiesCurrent_6B3A854CA8BC8DBAB903BA4BBF5FC303" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Other Liabilities, Current</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_OtherLiabilitiesCurrent" xlink:label="loc_us-gaap_OtherLiabilitiesCurrent_6B3A854CA8BC8DBAB903BA4BBF5FC303" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OtherLiabilitiesCurrent_6B3A854CA8BC8DBAB903BA4BBF5FC303" xlink:to="lab_us-gaap_OtherLiabilitiesCurrent_6B3A854CA8BC8DBAB903BA4BBF5FC303" xlink:type="arc" />
    <link:label id="lab_us-gaap_ShortTermBorrowings_1E8FE1A17288C7246C4CBA4BBF5FBE1E_terseLabel_en-US" xlink:label="lab_us-gaap_ShortTermBorrowings_1E8FE1A17288C7246C4CBA4BBF5FBE1E" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Short-term debt (P and R)</link:label>
    <link:label id="lab_us-gaap_ShortTermBorrowings_1E8FE1A17288C7246C4CBA4BBF5FBE1E_label_en-US" xlink:label="lab_us-gaap_ShortTermBorrowings_1E8FE1A17288C7246C4CBA4BBF5FBE1E" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Short-term Debt</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ShortTermBorrowings" xlink:label="loc_us-gaap_ShortTermBorrowings_1E8FE1A17288C7246C4CBA4BBF5FBE1E" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ShortTermBorrowings_1E8FE1A17288C7246C4CBA4BBF5FBE1E" xlink:to="lab_us-gaap_ShortTermBorrowings_1E8FE1A17288C7246C4CBA4BBF5FBE1E" xlink:type="arc" />
    <link:label id="lab_us-gaap_LiabilitiesCurrent_B711EEE7FC93FBEA149CBA4BBF5F2DE9_totalLabel_en-US" xlink:label="lab_us-gaap_LiabilitiesCurrent_B711EEE7FC93FBEA149CBA4BBF5F2DE9" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Total current liabilities</link:label>
    <link:label id="lab_us-gaap_LiabilitiesCurrent_B711EEE7FC93FBEA149CBA4BBF5F2DE9_label_en-US" xlink:label="lab_us-gaap_LiabilitiesCurrent_B711EEE7FC93FBEA149CBA4BBF5F2DE9" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Liabilities, Current</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_LiabilitiesCurrent" xlink:label="loc_us-gaap_LiabilitiesCurrent_B711EEE7FC93FBEA149CBA4BBF5F2DE9" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LiabilitiesCurrent_B711EEE7FC93FBEA149CBA4BBF5F2DE9" xlink:to="lab_us-gaap_LiabilitiesCurrent_B711EEE7FC93FBEA149CBA4BBF5F2DE9" xlink:type="arc" />
    <link:label id="lab_us-gaap_LongTermDebtAndCapitalLeaseObligations_16D0123D7A9280080D51BA4BBF5FAA4E_terseLabel_en-US" xlink:label="lab_us-gaap_LongTermDebtAndCapitalLeaseObligations_16D0123D7A9280080D51BA4BBF5FAA4E" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Long-term debt, less amount due within one year (P and R)</link:label>
    <link:label id="lab_us-gaap_LongTermDebtAndCapitalLeaseObligations_16D0123D7A9280080D51BA4BBF5FAA4E_label_en-US" xlink:label="lab_us-gaap_LongTermDebtAndCapitalLeaseObligations_16D0123D7A9280080D51BA4BBF5FAA4E" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Long-term Debt and Capital Lease Obligations</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_LongTermDebtAndCapitalLeaseObligations" xlink:label="loc_us-gaap_LongTermDebtAndCapitalLeaseObligations_16D0123D7A9280080D51BA4BBF5FAA4E" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LongTermDebtAndCapitalLeaseObligations_16D0123D7A9280080D51BA4BBF5FAA4E" xlink:to="lab_us-gaap_LongTermDebtAndCapitalLeaseObligations_16D0123D7A9280080D51BA4BBF5FAA4E" xlink:type="arc" />
    <link:label id="lab_us-gaap_DefinedBenefitPensionPlanLiabilitiesNoncurrent_84F87860619B9A7D3765BA4BBF5F622C_terseLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPensionPlanLiabilitiesNoncurrent_84F87860619B9A7D3765BA4BBF5F622C" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Accrued pension benefits (G)</link:label>
    <link:label id="lab_us-gaap_DefinedBenefitPensionPlanLiabilitiesNoncurrent_84F87860619B9A7D3765BA4BBF5F622C_label_en-US" xlink:label="lab_us-gaap_DefinedBenefitPensionPlanLiabilitiesNoncurrent_84F87860619B9A7D3765BA4BBF5F622C" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Liability, Defined Benefit Pension Plan, Noncurrent</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DefinedBenefitPensionPlanLiabilitiesNoncurrent" xlink:label="loc_us-gaap_DefinedBenefitPensionPlanLiabilitiesNoncurrent_84F87860619B9A7D3765BA4BBF5F622C" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPensionPlanLiabilitiesNoncurrent_84F87860619B9A7D3765BA4BBF5F622C" xlink:to="lab_us-gaap_DefinedBenefitPensionPlanLiabilitiesNoncurrent_84F87860619B9A7D3765BA4BBF5F622C" xlink:type="arc" />
    <link:label id="lab_us-gaap_OtherPostretirementDefinedBenefitPlanLiabilitiesNoncurrent_C3EC729A7EE7F77B9A0CBA4BBF5F0C51_terseLabel_en-US" xlink:label="lab_us-gaap_OtherPostretirementDefinedBenefitPlanLiabilitiesNoncurrent_C3EC729A7EE7F77B9A0CBA4BBF5F0C51" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Accrued other postretirement benefits (G)</link:label>
    <link:label id="lab_us-gaap_OtherPostretirementDefinedBenefitPlanLiabilitiesNoncurrent_C3EC729A7EE7F77B9A0CBA4BBF5F0C51_label_en-US" xlink:label="lab_us-gaap_OtherPostretirementDefinedBenefitPlanLiabilitiesNoncurrent_C3EC729A7EE7F77B9A0CBA4BBF5F0C51" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Liability, Other Postretirement Defined Benefit Plan, Noncurrent</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_OtherPostretirementDefinedBenefitPlanLiabilitiesNoncurrent" xlink:label="loc_us-gaap_OtherPostretirementDefinedBenefitPlanLiabilitiesNoncurrent_C3EC729A7EE7F77B9A0CBA4BBF5F0C51" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OtherPostretirementDefinedBenefitPlanLiabilitiesNoncurrent_C3EC729A7EE7F77B9A0CBA4BBF5F0C51" xlink:to="lab_us-gaap_OtherPostretirementDefinedBenefitPlanLiabilitiesNoncurrent_C3EC729A7EE7F77B9A0CBA4BBF5F0C51" xlink:type="arc" />
    <link:label id="lab_us-gaap_DeferredCreditsAndOtherLiabilitiesNoncurrent_457695760A6E2CF97DCBBA4BBF5F2618_terseLabel_en-US" xlink:label="lab_us-gaap_DeferredCreditsAndOtherLiabilitiesNoncurrent_457695760A6E2CF97DCBBA4BBF5F2618" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Other noncurrent liabilities and deferred credits (Q)</link:label>
    <link:label id="lab_us-gaap_DeferredCreditsAndOtherLiabilitiesNoncurrent_457695760A6E2CF97DCBBA4BBF5F2618_label_en-US" xlink:label="lab_us-gaap_DeferredCreditsAndOtherLiabilitiesNoncurrent_457695760A6E2CF97DCBBA4BBF5F2618" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Deferred Credits and Other Liabilities, Noncurrent</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DeferredCreditsAndOtherLiabilitiesNoncurrent" xlink:label="loc_us-gaap_DeferredCreditsAndOtherLiabilitiesNoncurrent_457695760A6E2CF97DCBBA4BBF5F2618" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DeferredCreditsAndOtherLiabilitiesNoncurrent_457695760A6E2CF97DCBBA4BBF5F2618" xlink:to="lab_us-gaap_DeferredCreditsAndOtherLiabilitiesNoncurrent_457695760A6E2CF97DCBBA4BBF5F2618" xlink:type="arc" />
    <link:label id="lab_us-gaap_Liabilities_5762D073C8D9BD4A563DBA4BBF5FC90C_totalLabel_en-US" xlink:label="lab_us-gaap_Liabilities_5762D073C8D9BD4A563DBA4BBF5FC90C" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Total liabilities</link:label>
    <link:label id="lab_us-gaap_Liabilities_5762D073C8D9BD4A563DBA4BBF5FC90C_label_en-US" xlink:label="lab_us-gaap_Liabilities_5762D073C8D9BD4A563DBA4BBF5FC90C" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Liabilities</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_Liabilities" xlink:label="loc_us-gaap_Liabilities_5762D073C8D9BD4A563DBA4BBF5FC90C" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_Liabilities_5762D073C8D9BD4A563DBA4BBF5FC90C" xlink:to="lab_us-gaap_Liabilities_5762D073C8D9BD4A563DBA4BBF5FC90C" xlink:type="arc" />
    <link:label id="lab_us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterestAbstract_B94693E2B7BAF93B378DBA4BBF5F7946_terseLabel_en-US" xlink:label="lab_us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterestAbstract_B94693E2B7BAF93B378DBA4BBF5F7946" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Equity</link:label>
    <link:label id="lab_us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterestAbstract_B94693E2B7BAF93B378DBA4BBF5F7946_label_en-US" xlink:label="lab_us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterestAbstract_B94693E2B7BAF93B378DBA4BBF5F7946" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest [Abstract]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterestAbstract" xlink:label="loc_us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterestAbstract_B94693E2B7BAF93B378DBA4BBF5F7946" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterestAbstract_B94693E2B7BAF93B378DBA4BBF5F7946" xlink:to="lab_us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterestAbstract_B94693E2B7BAF93B378DBA4BBF5F7946" xlink:type="arc" />
    <link:label id="lab_us-gaap_StockholdersEquityAbstract_BBC5B792E4DE7A9202FABA4BBF5F43B8_terseLabel_en-US" xlink:label="lab_us-gaap_StockholdersEquityAbstract_BBC5B792E4DE7A9202FABA4BBF5F43B8" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Arconic shareholders&#8217; equity:</link:label>
    <link:label id="lab_us-gaap_StockholdersEquityAbstract_BBC5B792E4DE7A9202FABA4BBF5F43B8_label_en-US" xlink:label="lab_us-gaap_StockholdersEquityAbstract_BBC5B792E4DE7A9202FABA4BBF5F43B8" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Stockholders' Equity Attributable to Parent [Abstract]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_StockholdersEquityAbstract" xlink:label="loc_us-gaap_StockholdersEquityAbstract_BBC5B792E4DE7A9202FABA4BBF5F43B8" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_StockholdersEquityAbstract_BBC5B792E4DE7A9202FABA4BBF5F43B8" xlink:to="lab_us-gaap_StockholdersEquityAbstract_BBC5B792E4DE7A9202FABA4BBF5F43B8" xlink:type="arc" />
    <link:label id="lab_us-gaap_PreferredStockValue_1D5F79F54D5C3BA69B60BA4BBF5FC3B4_terseLabel_en-US" xlink:label="lab_us-gaap_PreferredStockValue_1D5F79F54D5C3BA69B60BA4BBF5FC3B4" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Preferred stock (I)</link:label>
    <link:label id="lab_us-gaap_PreferredStockValue_1D5F79F54D5C3BA69B60BA4BBF5FC3B4_label_en-US" xlink:label="lab_us-gaap_PreferredStockValue_1D5F79F54D5C3BA69B60BA4BBF5FC3B4" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Preferred Stock, Value, Issued</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PreferredStockValue" xlink:label="loc_us-gaap_PreferredStockValue_1D5F79F54D5C3BA69B60BA4BBF5FC3B4" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PreferredStockValue_1D5F79F54D5C3BA69B60BA4BBF5FC3B4" xlink:to="lab_us-gaap_PreferredStockValue_1D5F79F54D5C3BA69B60BA4BBF5FC3B4" xlink:type="arc" />
    <link:label id="lab_us-gaap_CommonStockValue_81B041B41B491E9D40BBBA4BBF5FCE81_terseLabel_en-US" xlink:label="lab_us-gaap_CommonStockValue_81B041B41B491E9D40BBBA4BBF5FCE81" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Common stock (I)</link:label>
    <link:label id="lab_us-gaap_CommonStockValue_81B041B41B491E9D40BBBA4BBF5FCE81_label_en-US" xlink:label="lab_us-gaap_CommonStockValue_81B041B41B491E9D40BBBA4BBF5FCE81" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Common Stock, Value, Issued</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_CommonStockValue" xlink:label="loc_us-gaap_CommonStockValue_81B041B41B491E9D40BBBA4BBF5FCE81" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CommonStockValue_81B041B41B491E9D40BBBA4BBF5FCE81" xlink:to="lab_us-gaap_CommonStockValue_81B041B41B491E9D40BBBA4BBF5FCE81" xlink:type="arc" />
    <link:label id="lab_us-gaap_AdditionalPaidInCapital_D872D47BF1BED97C54FDBA4BBF5F6D9E_terseLabel_en-US" xlink:label="lab_us-gaap_AdditionalPaidInCapital_D872D47BF1BED97C54FDBA4BBF5F6D9E" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Additional capital</link:label>
    <link:label id="lab_us-gaap_AdditionalPaidInCapital_D872D47BF1BED97C54FDBA4BBF5F6D9E_label_en-US" xlink:label="lab_us-gaap_AdditionalPaidInCapital_D872D47BF1BED97C54FDBA4BBF5F6D9E" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Additional Paid in Capital</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AdditionalPaidInCapital" xlink:label="loc_us-gaap_AdditionalPaidInCapital_D872D47BF1BED97C54FDBA4BBF5F6D9E" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AdditionalPaidInCapital_D872D47BF1BED97C54FDBA4BBF5F6D9E" xlink:to="lab_us-gaap_AdditionalPaidInCapital_D872D47BF1BED97C54FDBA4BBF5F6D9E" xlink:type="arc" />
    <link:label id="lab_us-gaap_RetainedEarningsAccumulatedDeficit_F9B1C736021F0E83B1F5BA4BBF5F1F2F_terseLabel_en-US" xlink:label="lab_us-gaap_RetainedEarningsAccumulatedDeficit_F9B1C736021F0E83B1F5BA4BBF5F1F2F" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Accumulated deficit (A)</link:label>
    <link:label id="lab_us-gaap_RetainedEarningsAccumulatedDeficit_F9B1C736021F0E83B1F5BA4BBF5F1F2F_label_en-US" xlink:label="lab_us-gaap_RetainedEarningsAccumulatedDeficit_F9B1C736021F0E83B1F5BA4BBF5F1F2F" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Retained Earnings (Accumulated Deficit)</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RetainedEarningsAccumulatedDeficit" xlink:label="loc_us-gaap_RetainedEarningsAccumulatedDeficit_F9B1C736021F0E83B1F5BA4BBF5F1F2F" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RetainedEarningsAccumulatedDeficit_F9B1C736021F0E83B1F5BA4BBF5F1F2F" xlink:to="lab_us-gaap_RetainedEarningsAccumulatedDeficit_F9B1C736021F0E83B1F5BA4BBF5F1F2F" xlink:type="arc" />
    <link:label id="lab_us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax_9852650B2C556C5D86E9BA4BBF5F61FD_terseLabel_en-US" xlink:label="lab_us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax_9852650B2C556C5D86E9BA4BBF5F61FD" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Accumulated other comprehensive loss (A and K)</link:label>
    <link:label id="lab_us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax_9852650B2C556C5D86E9BA4BBF5F61FD_label_en-US" xlink:label="lab_us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax_9852650B2C556C5D86E9BA4BBF5F61FD" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Accumulated Other Comprehensive Income (Loss), Net of Tax</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax" xlink:label="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax_9852650B2C556C5D86E9BA4BBF5F61FD" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax_9852650B2C556C5D86E9BA4BBF5F61FD" xlink:to="lab_us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax_9852650B2C556C5D86E9BA4BBF5F61FD" xlink:type="arc" />
    <link:label id="lab_us-gaap_StockholdersEquity_033DC498D4F7E80FD4DABA4BBF5FA31F_totalLabel_en-US" xlink:label="lab_us-gaap_StockholdersEquity_033DC498D4F7E80FD4DABA4BBF5FA31F" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Total Arconic shareholders&#8217; equity</link:label>
    <link:label id="lab_us-gaap_StockholdersEquity_033DC498D4F7E80FD4DABA4BBF5FA31F_label_en-US" xlink:label="lab_us-gaap_StockholdersEquity_033DC498D4F7E80FD4DABA4BBF5FA31F" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Stockholders' Equity Attributable to Parent</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_StockholdersEquity" xlink:label="loc_us-gaap_StockholdersEquity_033DC498D4F7E80FD4DABA4BBF5FA31F" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_StockholdersEquity_033DC498D4F7E80FD4DABA4BBF5FA31F" xlink:to="lab_us-gaap_StockholdersEquity_033DC498D4F7E80FD4DABA4BBF5FA31F" xlink:type="arc" />
    <link:label id="lab_us-gaap_MinorityInterest_74A07783E7F3F3D03E1ABA4BBF5F48F0_verboseLabel_en-US" xlink:label="lab_us-gaap_MinorityInterest_74A07783E7F3F3D03E1ABA4BBF5F48F0" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Noncontrolling interests</link:label>
    <link:label id="lab_us-gaap_MinorityInterest_74A07783E7F3F3D03E1ABA4BBF5F48F0_label_en-US" xlink:label="lab_us-gaap_MinorityInterest_74A07783E7F3F3D03E1ABA4BBF5F48F0" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Stockholders' Equity Attributable to Noncontrolling Interest</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_MinorityInterest" xlink:label="loc_us-gaap_MinorityInterest_74A07783E7F3F3D03E1ABA4BBF5F48F0" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_MinorityInterest_74A07783E7F3F3D03E1ABA4BBF5F48F0" xlink:to="lab_us-gaap_MinorityInterest_74A07783E7F3F3D03E1ABA4BBF5F48F0" xlink:type="arc" />
    <link:label id="lab_us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest_00F62A01ACC94B5D6EF0BA4BBF5FE061_totalLabel_en-US" xlink:label="lab_us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest_00F62A01ACC94B5D6EF0BA4BBF5FE061" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Total equity</link:label>
    <link:label id="lab_us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest_00F62A01ACC94B5D6EF0BA4BBF5FE061_label_en-US" xlink:label="lab_us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest_00F62A01ACC94B5D6EF0BA4BBF5FE061" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest" xlink:label="loc_us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest_00F62A01ACC94B5D6EF0BA4BBF5FE061" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest_00F62A01ACC94B5D6EF0BA4BBF5FE061" xlink:to="lab_us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest_00F62A01ACC94B5D6EF0BA4BBF5FE061" xlink:type="arc" />
    <link:label id="lab_us-gaap_LiabilitiesAndStockholdersEquity_DCD80FBF9306591857C0BA4BBF5F2FD3_totalLabel_en-US" xlink:label="lab_us-gaap_LiabilitiesAndStockholdersEquity_DCD80FBF9306591857C0BA4BBF5F2FD3" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Total liabilities and equity</link:label>
    <link:label id="lab_us-gaap_LiabilitiesAndStockholdersEquity_DCD80FBF9306591857C0BA4BBF5F2FD3_label_en-US" xlink:label="lab_us-gaap_LiabilitiesAndStockholdersEquity_DCD80FBF9306591857C0BA4BBF5F2FD3" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Liabilities and Equity</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_LiabilitiesAndStockholdersEquity" xlink:label="loc_us-gaap_LiabilitiesAndStockholdersEquity_DCD80FBF9306591857C0BA4BBF5F2FD3" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LiabilitiesAndStockholdersEquity_DCD80FBF9306591857C0BA4BBF5F2FD3" xlink:to="lab_us-gaap_LiabilitiesAndStockholdersEquity_DCD80FBF9306591857C0BA4BBF5F2FD3" xlink:type="arc" />
    <link:label id="lab_us-gaap_OtherIncomeAndExpensesAbstract_0875ADEF1AB72D907F69EDFC596630DD_label_en-US" xlink:label="lab_us-gaap_OtherIncomeAndExpensesAbstract_0875ADEF1AB72D907F69EDFC596630DD" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Other Income and Expenses [Abstract]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_OtherIncomeAndExpensesAbstract" xlink:label="loc_us-gaap_OtherIncomeAndExpensesAbstract_0875ADEF1AB72D907F69EDFC596630DD" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OtherIncomeAndExpensesAbstract_0875ADEF1AB72D907F69EDFC596630DD" xlink:to="lab_us-gaap_OtherIncomeAndExpensesAbstract_0875ADEF1AB72D907F69EDFC596630DD" xlink:type="arc" />
    <link:label id="lab_arnc_NetPeriodicBenefitCostNonservice_B7C789E2FF9979EE5E47EDFC5967501E_terseLabel_en-US" xlink:label="lab_arnc_NetPeriodicBenefitCostNonservice_B7C789E2FF9979EE5E47EDFC5967501E" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Non-service related net periodic benefit cost</link:label>
    <link:label id="lab_arnc_NetPeriodicBenefitCostNonservice_B7C789E2FF9979EE5E47EDFC5967501E_label_en-US" xlink:label="lab_arnc_NetPeriodicBenefitCostNonservice_B7C789E2FF9979EE5E47EDFC5967501E" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Net Periodic Benefit Cost, Non-service</link:label>
    <link:label id="lab_arnc_NetPeriodicBenefitCostNonservice_B7C789E2FF9979EE5E47EDFC5967501E_documentation_en-US" xlink:label="lab_arnc_NetPeriodicBenefitCostNonservice_B7C789E2FF9979EE5E47EDFC5967501E" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Net Periodic Benefit Cost, Non-service</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_NetPeriodicBenefitCostNonservice" xlink:label="loc_arnc_NetPeriodicBenefitCostNonservice_B7C789E2FF9979EE5E47EDFC5967501E" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_NetPeriodicBenefitCostNonservice_B7C789E2FF9979EE5E47EDFC5967501E" xlink:to="lab_arnc_NetPeriodicBenefitCostNonservice_B7C789E2FF9979EE5E47EDFC5967501E" xlink:type="arc" />
    <link:label id="lab_us-gaap_InterestIncomeExpenseNonoperatingNet_0EFD2AD1567BE9ED43D3EDFC5967E2C9_negatedLabel_en-US" xlink:label="lab_us-gaap_InterestIncomeExpenseNonoperatingNet_0EFD2AD1567BE9ED43D3EDFC5967E2C9" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xml:lang="en-US">Interest income</link:label>
    <link:label id="lab_us-gaap_InterestIncomeExpenseNonoperatingNet_0EFD2AD1567BE9ED43D3EDFC5967E2C9_label_en-US" xlink:label="lab_us-gaap_InterestIncomeExpenseNonoperatingNet_0EFD2AD1567BE9ED43D3EDFC5967E2C9" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Interest Income (Expense), Nonoperating, Net</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_InterestIncomeExpenseNonoperatingNet" xlink:label="loc_us-gaap_InterestIncomeExpenseNonoperatingNet_0EFD2AD1567BE9ED43D3EDFC5967E2C9" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_InterestIncomeExpenseNonoperatingNet_0EFD2AD1567BE9ED43D3EDFC5967E2C9" xlink:to="lab_us-gaap_InterestIncomeExpenseNonoperatingNet_0EFD2AD1567BE9ED43D3EDFC5967E2C9" xlink:type="arc" />
    <link:label id="lab_us-gaap_ForeignCurrencyTransactionGainLossBeforeTax_53B2640B6606DABC145AEDFC596773A0_negatedTerseLabel_en-US" xlink:label="lab_us-gaap_ForeignCurrencyTransactionGainLossBeforeTax_53B2640B6606DABC145AEDFC596773A0" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:type="resource" xml:lang="en-US">Foreign currency losses (gains), net</link:label>
    <link:label id="lab_us-gaap_ForeignCurrencyTransactionGainLossBeforeTax_53B2640B6606DABC145AEDFC596773A0_label_en-US" xlink:label="lab_us-gaap_ForeignCurrencyTransactionGainLossBeforeTax_53B2640B6606DABC145AEDFC596773A0" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Foreign Currency Transaction Gain (Loss), before Tax</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ForeignCurrencyTransactionGainLossBeforeTax" xlink:label="loc_us-gaap_ForeignCurrencyTransactionGainLossBeforeTax_53B2640B6606DABC145AEDFC596773A0" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ForeignCurrencyTransactionGainLossBeforeTax_53B2640B6606DABC145AEDFC596773A0" xlink:to="lab_us-gaap_ForeignCurrencyTransactionGainLossBeforeTax_53B2640B6606DABC145AEDFC596773A0" xlink:type="arc" />
    <link:label id="lab_us-gaap_GainLossOnDispositionOfAssets1_396B16F0C72C0CFEFD0AEDFC59676A7E_negatedTerseLabel_en-US" xlink:label="lab_us-gaap_GainLossOnDispositionOfAssets1_396B16F0C72C0CFEFD0AEDFC59676A7E" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:type="resource" xml:lang="en-US">Net loss (gain) from asset sales</link:label>
    <link:label id="lab_us-gaap_GainLossOnDispositionOfAssets1_396B16F0C72C0CFEFD0AEDFC59676A7E_label_en-US" xlink:label="lab_us-gaap_GainLossOnDispositionOfAssets1_396B16F0C72C0CFEFD0AEDFC59676A7E" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Gain (Loss) on Disposition of Assets</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_GainLossOnDispositionOfAssets1" xlink:label="loc_us-gaap_GainLossOnDispositionOfAssets1_396B16F0C72C0CFEFD0AEDFC59676A7E" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_GainLossOnDispositionOfAssets1_396B16F0C72C0CFEFD0AEDFC59676A7E" xlink:to="lab_us-gaap_GainLossOnDispositionOfAssets1_396B16F0C72C0CFEFD0AEDFC59676A7E" xlink:type="arc" />
    <link:label id="lab_us-gaap_OtherNonoperatingIncomeExpense_449E222A42C3670D6276EDFC59672292_negatedTerseLabel_en-US" xlink:label="lab_us-gaap_OtherNonoperatingIncomeExpense_449E222A42C3670D6276EDFC59672292" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:type="resource" xml:lang="en-US">Other, net</link:label>
    <link:label id="lab_us-gaap_OtherNonoperatingIncomeExpense_449E222A42C3670D6276EDFC59672292_label_en-US" xlink:label="lab_us-gaap_OtherNonoperatingIncomeExpense_449E222A42C3670D6276EDFC59672292" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Other Nonoperating Income (Expense)</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_OtherNonoperatingIncomeExpense" xlink:label="loc_us-gaap_OtherNonoperatingIncomeExpense_449E222A42C3670D6276EDFC59672292" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OtherNonoperatingIncomeExpense_449E222A42C3670D6276EDFC59672292" xlink:to="lab_us-gaap_OtherNonoperatingIncomeExpense_449E222A42C3670D6276EDFC59672292" xlink:type="arc" />
    <link:label id="lab_us-gaap_NonoperatingIncomeExpense_2C13AA4FF5C0B74773FCEDFC5967C7D9_negatedTotalLabel_en-US" xlink:label="lab_us-gaap_NonoperatingIncomeExpense_2C13AA4FF5C0B74773FCEDFC5967C7D9" xlink:role="http://www.xbrl.org/2009/role/negatedTotalLabel" xlink:type="resource" xml:lang="en-US">Other income, net</link:label>
    <link:label id="lab_us-gaap_NonoperatingIncomeExpense_2C13AA4FF5C0B74773FCEDFC5967C7D9_label_en-US" xlink:label="lab_us-gaap_NonoperatingIncomeExpense_2C13AA4FF5C0B74773FCEDFC5967C7D9" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Nonoperating Income (Expense)</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_NonoperatingIncomeExpense" xlink:label="loc_us-gaap_NonoperatingIncomeExpense_2C13AA4FF5C0B74773FCEDFC5967C7D9" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_NonoperatingIncomeExpense_2C13AA4FF5C0B74773FCEDFC5967C7D9" xlink:to="lab_us-gaap_NonoperatingIncomeExpense_2C13AA4FF5C0B74773FCEDFC5967C7D9" xlink:type="arc" />
    <link:label id="lab_us-gaap_ScheduleOfRevenuesFromExternalCustomersAndLongLivedAssetsTable_3AC43085F303A7623E31C968C29FADB0_terseLabel_en-US" xlink:label="lab_us-gaap_ScheduleOfRevenuesFromExternalCustomersAndLongLivedAssetsTable_3AC43085F303A7623E31C968C29FADB0" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Schedule of Revenues from External Customers and Long-Lived Assets [Table]</link:label>
    <link:label id="lab_us-gaap_ScheduleOfRevenuesFromExternalCustomersAndLongLivedAssetsTable_3AC43085F303A7623E31C968C29FADB0_label_en-US" xlink:label="lab_us-gaap_ScheduleOfRevenuesFromExternalCustomersAndLongLivedAssetsTable_3AC43085F303A7623E31C968C29FADB0" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Schedule of Revenues from External Customers and Long-Lived Assets [Table]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ScheduleOfRevenuesFromExternalCustomersAndLongLivedAssetsTable" xlink:label="loc_us-gaap_ScheduleOfRevenuesFromExternalCustomersAndLongLivedAssetsTable_3AC43085F303A7623E31C968C29FADB0" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfRevenuesFromExternalCustomersAndLongLivedAssetsTable_3AC43085F303A7623E31C968C29FADB0" xlink:to="lab_us-gaap_ScheduleOfRevenuesFromExternalCustomersAndLongLivedAssetsTable_3AC43085F303A7623E31C968C29FADB0" xlink:type="arc" />
    <link:label id="lab_srt_StatementGeographicalAxis_BCAA710544A2C4C13F66C968C29F7F4A_terseLabel_en-US" xlink:label="lab_srt_StatementGeographicalAxis_BCAA710544A2C4C13F66C968C29F7F4A" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Geographical [Axis]</link:label>
    <link:label id="lab_srt_StatementGeographicalAxis_BCAA710544A2C4C13F66C968C29F7F4A_label_en-US" xlink:label="lab_srt_StatementGeographicalAxis_BCAA710544A2C4C13F66C968C29F7F4A" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Geographical [Axis]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_StatementGeographicalAxis" xlink:label="loc_srt_StatementGeographicalAxis_BCAA710544A2C4C13F66C968C29F7F4A" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_srt_StatementGeographicalAxis_BCAA710544A2C4C13F66C968C29F7F4A" xlink:to="lab_srt_StatementGeographicalAxis_BCAA710544A2C4C13F66C968C29F7F4A" xlink:type="arc" />
    <link:label id="lab_srt_SegmentGeographicalDomain_2900DF0E13A4F70F68E8C968C2A07088_terseLabel_en-US" xlink:label="lab_srt_SegmentGeographicalDomain_2900DF0E13A4F70F68E8C968C2A07088" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Geographical [Domain]</link:label>
    <link:label id="lab_srt_SegmentGeographicalDomain_2900DF0E13A4F70F68E8C968C2A07088_label_en-US" xlink:label="lab_srt_SegmentGeographicalDomain_2900DF0E13A4F70F68E8C968C2A07088" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Geographical [Domain]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_SegmentGeographicalDomain" xlink:label="loc_srt_SegmentGeographicalDomain_2900DF0E13A4F70F68E8C968C2A07088" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_srt_SegmentGeographicalDomain_2900DF0E13A4F70F68E8C968C2A07088" xlink:to="lab_srt_SegmentGeographicalDomain_2900DF0E13A4F70F68E8C968C2A07088" xlink:type="arc" />
    <link:label id="lab_country_FR_60BEACB1DA249B25CB70C968C2A543D6_terseLabel_en-US" xlink:label="lab_country_FR_60BEACB1DA249B25CB70C968C2A543D6" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">France</link:label>
    <link:label id="lab_country_FR_60BEACB1DA249B25CB70C968C2A543D6_label_en-US" xlink:label="lab_country_FR_60BEACB1DA249B25CB70C968C2A543D6" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">FRANCE</link:label>
    <link:loc xlink:href="http://xbrl.sec.gov/country/2017/country-2017-01-31.xsd#country_FR" xlink:label="loc_country_FR_60BEACB1DA249B25CB70C968C2A543D6" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_country_FR_60BEACB1DA249B25CB70C968C2A543D6" xlink:to="lab_country_FR_60BEACB1DA249B25CB70C968C2A543D6" xlink:type="arc" />
    <link:label id="lab_country_HU_529405D0807814B554FDC968C2A5BE15_terseLabel_en-US" xlink:label="lab_country_HU_529405D0807814B554FDC968C2A5BE15" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Hungary</link:label>
    <link:label id="lab_country_HU_529405D0807814B554FDC968C2A5BE15_label_en-US" xlink:label="lab_country_HU_529405D0807814B554FDC968C2A5BE15" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">HUNGARY</link:label>
    <link:loc xlink:href="http://xbrl.sec.gov/country/2017/country-2017-01-31.xsd#country_HU" xlink:label="loc_country_HU_529405D0807814B554FDC968C2A5BE15" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_country_HU_529405D0807814B554FDC968C2A5BE15" xlink:to="lab_country_HU_529405D0807814B554FDC968C2A5BE15" xlink:type="arc" />
    <link:label id="lab_country_GB_B7EB397F8BF4BEF497D8C968C2A6A2E4_terseLabel_en-US" xlink:label="lab_country_GB_B7EB397F8BF4BEF497D8C968C2A6A2E4" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">United Kingdom</link:label>
    <link:label id="lab_country_GB_B7EB397F8BF4BEF497D8C968C2A6A2E4_label_en-US" xlink:label="lab_country_GB_B7EB397F8BF4BEF497D8C968C2A6A2E4" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">UNITED KINGDOM</link:label>
    <link:loc xlink:href="http://xbrl.sec.gov/country/2017/country-2017-01-31.xsd#country_GB" xlink:label="loc_country_GB_B7EB397F8BF4BEF497D8C968C2A6A2E4" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_country_GB_B7EB397F8BF4BEF497D8C968C2A6A2E4" xlink:to="lab_country_GB_B7EB397F8BF4BEF497D8C968C2A6A2E4" xlink:type="arc" />
    <link:label id="lab_country_CN_E1CAA5D2D14C208B6F53C968C2A6E2CC_terseLabel_en-US" xlink:label="lab_country_CN_E1CAA5D2D14C208B6F53C968C2A6E2CC" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">China</link:label>
    <link:label id="lab_country_CN_E1CAA5D2D14C208B6F53C968C2A6E2CC_label_en-US" xlink:label="lab_country_CN_E1CAA5D2D14C208B6F53C968C2A6E2CC" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">CHINA</link:label>
    <link:loc xlink:href="http://xbrl.sec.gov/country/2017/country-2017-01-31.xsd#country_CN" xlink:label="loc_country_CN_E1CAA5D2D14C208B6F53C968C2A6E2CC" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_country_CN_E1CAA5D2D14C208B6F53C968C2A6E2CC" xlink:to="lab_country_CN_E1CAA5D2D14C208B6F53C968C2A6E2CC" xlink:type="arc" />
    <link:label id="lab_country_RU_CBA160EDC3F6456FBB91C968C2A6FB21_terseLabel_en-US" xlink:label="lab_country_RU_CBA160EDC3F6456FBB91C968C2A6FB21" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Russia</link:label>
    <link:label id="lab_country_RU_CBA160EDC3F6456FBB91C968C2A6FB21_label_en-US" xlink:label="lab_country_RU_CBA160EDC3F6456FBB91C968C2A6FB21" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">RUSSIAN FEDERATION</link:label>
    <link:loc xlink:href="http://xbrl.sec.gov/country/2017/country-2017-01-31.xsd#country_RU" xlink:label="loc_country_RU_CBA160EDC3F6456FBB91C968C2A6FB21" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_country_RU_CBA160EDC3F6456FBB91C968C2A6FB21" xlink:to="lab_country_RU_CBA160EDC3F6456FBB91C968C2A6FB21" xlink:type="arc" />
    <link:label id="lab_country_DE_FDA0166E85569AA423EAC968C2A7FD6F_terseLabel_en-US" xlink:label="lab_country_DE_FDA0166E85569AA423EAC968C2A7FD6F" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Germany</link:label>
    <link:label id="lab_country_DE_FDA0166E85569AA423EAC968C2A7FD6F_label_en-US" xlink:label="lab_country_DE_FDA0166E85569AA423EAC968C2A7FD6F" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">GERMANY</link:label>
    <link:loc xlink:href="http://xbrl.sec.gov/country/2017/country-2017-01-31.xsd#country_DE" xlink:label="loc_country_DE_FDA0166E85569AA423EAC968C2A7FD6F" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_country_DE_FDA0166E85569AA423EAC968C2A7FD6F" xlink:to="lab_country_DE_FDA0166E85569AA423EAC968C2A7FD6F" xlink:type="arc" />
    <link:label id="lab_country_CA_344010348FFCDA821F75C968C2A7C39D_terseLabel_en-US" xlink:label="lab_country_CA_344010348FFCDA821F75C968C2A7C39D" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Canada</link:label>
    <link:label id="lab_country_CA_344010348FFCDA821F75C968C2A7C39D_label_en-US" xlink:label="lab_country_CA_344010348FFCDA821F75C968C2A7C39D" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">CANADA</link:label>
    <link:loc xlink:href="http://xbrl.sec.gov/country/2017/country-2017-01-31.xsd#country_CA" xlink:label="loc_country_CA_344010348FFCDA821F75C968C2A7C39D" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_country_CA_344010348FFCDA821F75C968C2A7C39D" xlink:to="lab_country_CA_344010348FFCDA821F75C968C2A7C39D" xlink:type="arc" />
    <link:label id="lab_country_BR_AEB75B8346AF57A6D525C968C2A7E9C2_terseLabel_en-US" xlink:label="lab_country_BR_AEB75B8346AF57A6D525C968C2A7E9C2" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Brazil</link:label>
    <link:label id="lab_country_BR_AEB75B8346AF57A6D525C968C2A7E9C2_label_en-US" xlink:label="lab_country_BR_AEB75B8346AF57A6D525C968C2A7E9C2" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">BRAZIL</link:label>
    <link:loc xlink:href="http://xbrl.sec.gov/country/2017/country-2017-01-31.xsd#country_BR" xlink:label="loc_country_BR_AEB75B8346AF57A6D525C968C2A7E9C2" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_country_BR_AEB75B8346AF57A6D525C968C2A7E9C2" xlink:to="lab_country_BR_AEB75B8346AF57A6D525C968C2A7E9C2" xlink:type="arc" />
    <link:label id="lab_country_JP_918A7420CF3977A83C3AC968C2A78C50_verboseLabel_en-US" xlink:label="lab_country_JP_918A7420CF3977A83C3AC968C2A78C50" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Japan</link:label>
    <link:label id="lab_country_JP_918A7420CF3977A83C3AC968C2A78C50_label_en-US" xlink:label="lab_country_JP_918A7420CF3977A83C3AC968C2A78C50" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">JAPAN</link:label>
    <link:loc xlink:href="http://xbrl.sec.gov/country/2017/country-2017-01-31.xsd#country_JP" xlink:label="loc_country_JP_918A7420CF3977A83C3AC968C2A78C50" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_country_JP_918A7420CF3977A83C3AC968C2A78C50" xlink:to="lab_country_JP_918A7420CF3977A83C3AC968C2A78C50" xlink:type="arc" />
    <link:label id="lab_arnc_OtherGeographicalRegionsMember_8E6408CD0F9D3D322DA4C968C2A7EEF8_terseLabel_en-US" xlink:label="lab_arnc_OtherGeographicalRegionsMember_8E6408CD0F9D3D322DA4C968C2A7EEF8" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Other</link:label>
    <link:label id="lab_arnc_OtherGeographicalRegionsMember_8E6408CD0F9D3D322DA4C968C2A7EEF8_label_en-US" xlink:label="lab_arnc_OtherGeographicalRegionsMember_8E6408CD0F9D3D322DA4C968C2A7EEF8" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Other Geographical Regions [Member]</link:label>
    <link:label id="lab_arnc_OtherGeographicalRegionsMember_8E6408CD0F9D3D322DA4C968C2A7EEF8_documentation_en-US" xlink:label="lab_arnc_OtherGeographicalRegionsMember_8E6408CD0F9D3D322DA4C968C2A7EEF8" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Other geographical regions.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_OtherGeographicalRegionsMember" xlink:label="loc_arnc_OtherGeographicalRegionsMember_8E6408CD0F9D3D322DA4C968C2A7EEF8" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_OtherGeographicalRegionsMember_8E6408CD0F9D3D322DA4C968C2A7EEF8" xlink:to="lab_arnc_OtherGeographicalRegionsMember_8E6408CD0F9D3D322DA4C968C2A7EEF8" xlink:type="arc" />
    <link:label id="lab_us-gaap_RevenuesFromExternalCustomersAndLongLivedAssetsLineItems_AE8A6349D266829B7FD5C968C2A8F5F9_terseLabel_en-US" xlink:label="lab_us-gaap_RevenuesFromExternalCustomersAndLongLivedAssetsLineItems_AE8A6349D266829B7FD5C968C2A8F5F9" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Revenues from External Customers and Long-Lived Assets [Line Items]</link:label>
    <link:label id="lab_us-gaap_RevenuesFromExternalCustomersAndLongLivedAssetsLineItems_AE8A6349D266829B7FD5C968C2A8F5F9_label_en-US" xlink:label="lab_us-gaap_RevenuesFromExternalCustomersAndLongLivedAssetsLineItems_AE8A6349D266829B7FD5C968C2A8F5F9" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Revenues from External Customers and Long-Lived Assets [Line Items]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RevenuesFromExternalCustomersAndLongLivedAssetsLineItems" xlink:label="loc_us-gaap_RevenuesFromExternalCustomersAndLongLivedAssetsLineItems_AE8A6349D266829B7FD5C968C2A8F5F9" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RevenuesFromExternalCustomersAndLongLivedAssetsLineItems_AE8A6349D266829B7FD5C968C2A8F5F9" xlink:to="lab_us-gaap_RevenuesFromExternalCustomersAndLongLivedAssetsLineItems_AE8A6349D266829B7FD5C968C2A8F5F9" xlink:type="arc" />
    <link:label id="lab_us-gaap_DisposalGroupIncludingDiscontinuedOperationCostsOfGoodsSold_F43314A30B69F820A19506E20A5A5C80_terseLabel_en-US" xlink:label="lab_us-gaap_DisposalGroupIncludingDiscontinuedOperationCostsOfGoodsSold_F43314A30B69F820A19506E20A5A5C80" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Cost of goods sold (exclusive of expenses below)</link:label>
    <link:label id="lab_us-gaap_DisposalGroupIncludingDiscontinuedOperationCostsOfGoodsSold_F43314A30B69F820A19506E20A5A5C80_label_en-US" xlink:label="lab_us-gaap_DisposalGroupIncludingDiscontinuedOperationCostsOfGoodsSold_F43314A30B69F820A19506E20A5A5C80" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Disposal Group, Including Discontinued Operation, Costs of Goods Sold</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DisposalGroupIncludingDiscontinuedOperationCostsOfGoodsSold" xlink:label="loc_us-gaap_DisposalGroupIncludingDiscontinuedOperationCostsOfGoodsSold_F43314A30B69F820A19506E20A5A5C80" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DisposalGroupIncludingDiscontinuedOperationCostsOfGoodsSold_F43314A30B69F820A19506E20A5A5C80" xlink:to="lab_us-gaap_DisposalGroupIncludingDiscontinuedOperationCostsOfGoodsSold_F43314A30B69F820A19506E20A5A5C80" xlink:type="arc" />
    <link:label id="lab_us-gaap_DisposalGroupIncludingDiscontinuedOperationGeneralAndAdministrativeExpense_8806E7AE7999BC7EB5DF06E20A5A201A_terseLabel_en-US" xlink:label="lab_us-gaap_DisposalGroupIncludingDiscontinuedOperationGeneralAndAdministrativeExpense_8806E7AE7999BC7EB5DF06E20A5A201A" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Selling, general administrative, and other expenses</link:label>
    <link:label id="lab_us-gaap_DisposalGroupIncludingDiscontinuedOperationGeneralAndAdministrativeExpense_8806E7AE7999BC7EB5DF06E20A5A201A_label_en-US" xlink:label="lab_us-gaap_DisposalGroupIncludingDiscontinuedOperationGeneralAndAdministrativeExpense_8806E7AE7999BC7EB5DF06E20A5A201A" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Disposal Group, Including Discontinued Operation, General and Administrative Expense</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DisposalGroupIncludingDiscontinuedOperationGeneralAndAdministrativeExpense" xlink:label="loc_us-gaap_DisposalGroupIncludingDiscontinuedOperationGeneralAndAdministrativeExpense_8806E7AE7999BC7EB5DF06E20A5A201A" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DisposalGroupIncludingDiscontinuedOperationGeneralAndAdministrativeExpense_8806E7AE7999BC7EB5DF06E20A5A201A" xlink:to="lab_us-gaap_DisposalGroupIncludingDiscontinuedOperationGeneralAndAdministrativeExpense_8806E7AE7999BC7EB5DF06E20A5A201A" xlink:type="arc" />
    <link:label id="lab_arnc_DisposalGroupIncludingDiscontinuedOperationResearchAndDevelopment_879AA057BFC4D8ACFFEC06E20A5A19C3_terseLabel_en-US" xlink:label="lab_arnc_DisposalGroupIncludingDiscontinuedOperationResearchAndDevelopment_879AA057BFC4D8ACFFEC06E20A5A19C3" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Research and development</link:label>
    <link:label id="lab_arnc_DisposalGroupIncludingDiscontinuedOperationResearchAndDevelopment_879AA057BFC4D8ACFFEC06E20A5A19C3_label_en-US" xlink:label="lab_arnc_DisposalGroupIncludingDiscontinuedOperationResearchAndDevelopment_879AA057BFC4D8ACFFEC06E20A5A19C3" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Disposal Group Including Discontinued Operation Research And Development</link:label>
    <link:label id="lab_arnc_DisposalGroupIncludingDiscontinuedOperationResearchAndDevelopment_879AA057BFC4D8ACFFEC06E20A5A19C3_documentation_en-US" xlink:label="lab_arnc_DisposalGroupIncludingDiscontinuedOperationResearchAndDevelopment_879AA057BFC4D8ACFFEC06E20A5A19C3" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Disposal group including discontinued operation research and development.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_DisposalGroupIncludingDiscontinuedOperationResearchAndDevelopment" xlink:label="loc_arnc_DisposalGroupIncludingDiscontinuedOperationResearchAndDevelopment_879AA057BFC4D8ACFFEC06E20A5A19C3" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_DisposalGroupIncludingDiscontinuedOperationResearchAndDevelopment_879AA057BFC4D8ACFFEC06E20A5A19C3" xlink:to="lab_arnc_DisposalGroupIncludingDiscontinuedOperationResearchAndDevelopment_879AA057BFC4D8ACFFEC06E20A5A19C3" xlink:type="arc" />
    <link:label id="lab_us-gaap_DisposalGroupIncludingDiscontinuedOperationDepreciationAndAmortization_69D04EAA431B73866F6206E20A5B8FE0_terseLabel_en-US" xlink:label="lab_us-gaap_DisposalGroupIncludingDiscontinuedOperationDepreciationAndAmortization_69D04EAA431B73866F6206E20A5B8FE0" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Provision for depreciation, depletion and amortization</link:label>
    <link:label id="lab_us-gaap_DisposalGroupIncludingDiscontinuedOperationDepreciationAndAmortization_69D04EAA431B73866F6206E20A5B8FE0_label_en-US" xlink:label="lab_us-gaap_DisposalGroupIncludingDiscontinuedOperationDepreciationAndAmortization_69D04EAA431B73866F6206E20A5B8FE0" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Disposal Group, Including Discontinued Operation, Depreciation and Amortization</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DisposalGroupIncludingDiscontinuedOperationDepreciationAndAmortization" xlink:label="loc_us-gaap_DisposalGroupIncludingDiscontinuedOperationDepreciationAndAmortization_69D04EAA431B73866F6206E20A5B8FE0" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DisposalGroupIncludingDiscontinuedOperationDepreciationAndAmortization_69D04EAA431B73866F6206E20A5B8FE0" xlink:to="lab_us-gaap_DisposalGroupIncludingDiscontinuedOperationDepreciationAndAmortization_69D04EAA431B73866F6206E20A5B8FE0" xlink:type="arc" />
    <link:label id="lab_arnc_DisposalGroupIncludingDiscontinuedOperationRestructuringAndOtherCharges_B12E53B8340370644B4D06E20A5BCDFE_terseLabel_en-US" xlink:label="lab_arnc_DisposalGroupIncludingDiscontinuedOperationRestructuringAndOtherCharges_B12E53B8340370644B4D06E20A5BCDFE" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Restructuring and other charges</link:label>
    <link:label id="lab_arnc_DisposalGroupIncludingDiscontinuedOperationRestructuringAndOtherCharges_B12E53B8340370644B4D06E20A5BCDFE_label_en-US" xlink:label="lab_arnc_DisposalGroupIncludingDiscontinuedOperationRestructuringAndOtherCharges_B12E53B8340370644B4D06E20A5BCDFE" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Disposal Group Including Discontinued Operation Restructuring And Other Charges</link:label>
    <link:label id="lab_arnc_DisposalGroupIncludingDiscontinuedOperationRestructuringAndOtherCharges_B12E53B8340370644B4D06E20A5BCDFE_documentation_en-US" xlink:label="lab_arnc_DisposalGroupIncludingDiscontinuedOperationRestructuringAndOtherCharges_B12E53B8340370644B4D06E20A5BCDFE" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Disposal group including discontinued operation restructuring and other charges.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_DisposalGroupIncludingDiscontinuedOperationRestructuringAndOtherCharges" xlink:label="loc_arnc_DisposalGroupIncludingDiscontinuedOperationRestructuringAndOtherCharges_B12E53B8340370644B4D06E20A5BCDFE" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_DisposalGroupIncludingDiscontinuedOperationRestructuringAndOtherCharges_B12E53B8340370644B4D06E20A5BCDFE" xlink:to="lab_arnc_DisposalGroupIncludingDiscontinuedOperationRestructuringAndOtherCharges_B12E53B8340370644B4D06E20A5BCDFE" xlink:type="arc" />
    <link:label id="lab_us-gaap_DisposalGroupIncludingDiscontinuedOperationInterestExpense_3FCC0F3411A413FF063606E20A5BC4DC_terseLabel_en-US" xlink:label="lab_us-gaap_DisposalGroupIncludingDiscontinuedOperationInterestExpense_3FCC0F3411A413FF063606E20A5BC4DC" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Interest expense</link:label>
    <link:label id="lab_us-gaap_DisposalGroupIncludingDiscontinuedOperationInterestExpense_3FCC0F3411A413FF063606E20A5BC4DC_label_en-US" xlink:label="lab_us-gaap_DisposalGroupIncludingDiscontinuedOperationInterestExpense_3FCC0F3411A413FF063606E20A5BC4DC" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Disposal Group, Including Discontinued Operation, Interest Expense</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DisposalGroupIncludingDiscontinuedOperationInterestExpense" xlink:label="loc_us-gaap_DisposalGroupIncludingDiscontinuedOperationInterestExpense_3FCC0F3411A413FF063606E20A5BC4DC" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DisposalGroupIncludingDiscontinuedOperationInterestExpense_3FCC0F3411A413FF063606E20A5BC4DC" xlink:to="lab_us-gaap_DisposalGroupIncludingDiscontinuedOperationInterestExpense_3FCC0F3411A413FF063606E20A5BC4DC" xlink:type="arc" />
    <link:label id="lab_arnc_DisposalGroupIncludingDiscontinuedOperationOtherIncomeExpense_AA75C2C0A691732A3D5706E20A5B973F_negatedTerseLabel_en-US" xlink:label="lab_arnc_DisposalGroupIncludingDiscontinuedOperationOtherIncomeExpense_AA75C2C0A691732A3D5706E20A5B973F" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:type="resource" xml:lang="en-US">Other (income) expenses, net</link:label>
    <link:label id="lab_arnc_DisposalGroupIncludingDiscontinuedOperationOtherIncomeExpense_AA75C2C0A691732A3D5706E20A5B973F_label_en-US" xlink:label="lab_arnc_DisposalGroupIncludingDiscontinuedOperationOtherIncomeExpense_AA75C2C0A691732A3D5706E20A5B973F" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Disposal Group Including Discontinued Operation Other Income Expense</link:label>
    <link:label id="lab_arnc_DisposalGroupIncludingDiscontinuedOperationOtherIncomeExpense_AA75C2C0A691732A3D5706E20A5B973F_documentation_en-US" xlink:label="lab_arnc_DisposalGroupIncludingDiscontinuedOperationOtherIncomeExpense_AA75C2C0A691732A3D5706E20A5B973F" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Disposal group including discontinued operation other income expense.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_DisposalGroupIncludingDiscontinuedOperationOtherIncomeExpense" xlink:label="loc_arnc_DisposalGroupIncludingDiscontinuedOperationOtherIncomeExpense_AA75C2C0A691732A3D5706E20A5B973F" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_DisposalGroupIncludingDiscontinuedOperationOtherIncomeExpense_AA75C2C0A691732A3D5706E20A5B973F" xlink:to="lab_arnc_DisposalGroupIncludingDiscontinuedOperationOtherIncomeExpense_AA75C2C0A691732A3D5706E20A5B973F" xlink:type="arc" />
    <link:label id="lab_us-gaap_DiscontinuedOperationIncomeLossFromDiscontinuedOperationBeforeIncomeTax_ECB0FA03D18D6C6424BB06E20A5B9CE1_totalLabel_en-US" xlink:label="lab_us-gaap_DiscontinuedOperationIncomeLossFromDiscontinuedOperationBeforeIncomeTax_ECB0FA03D18D6C6424BB06E20A5B9CE1" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Income from discontinued operations before income taxes</link:label>
    <link:label id="lab_us-gaap_DiscontinuedOperationIncomeLossFromDiscontinuedOperationBeforeIncomeTax_ECB0FA03D18D6C6424BB06E20A5B9CE1_label_en-US" xlink:label="lab_us-gaap_DiscontinuedOperationIncomeLossFromDiscontinuedOperationBeforeIncomeTax_ECB0FA03D18D6C6424BB06E20A5B9CE1" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Discontinued Operation, Income (Loss) from Discontinued Operation, before Income Tax</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DiscontinuedOperationIncomeLossFromDiscontinuedOperationBeforeIncomeTax" xlink:label="loc_us-gaap_DiscontinuedOperationIncomeLossFromDiscontinuedOperationBeforeIncomeTax_ECB0FA03D18D6C6424BB06E20A5B9CE1" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DiscontinuedOperationIncomeLossFromDiscontinuedOperationBeforeIncomeTax_ECB0FA03D18D6C6424BB06E20A5B9CE1" xlink:to="lab_us-gaap_DiscontinuedOperationIncomeLossFromDiscontinuedOperationBeforeIncomeTax_ECB0FA03D18D6C6424BB06E20A5B9CE1" xlink:type="arc" />
    <link:label id="lab_us-gaap_DiscontinuedOperationTaxEffectOfDiscontinuedOperation_2E9F3BA614D7EE1FA58F06E20A5B0B43_terseLabel_en-US" xlink:label="lab_us-gaap_DiscontinuedOperationTaxEffectOfDiscontinuedOperation_2E9F3BA614D7EE1FA58F06E20A5B0B43" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Provision for income taxes</link:label>
    <link:label id="lab_us-gaap_DiscontinuedOperationTaxEffectOfDiscontinuedOperation_2E9F3BA614D7EE1FA58F06E20A5B0B43_label_en-US" xlink:label="lab_us-gaap_DiscontinuedOperationTaxEffectOfDiscontinuedOperation_2E9F3BA614D7EE1FA58F06E20A5B0B43" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Discontinued Operation, Tax Effect of Discontinued Operation</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DiscontinuedOperationTaxEffectOfDiscontinuedOperation" xlink:label="loc_us-gaap_DiscontinuedOperationTaxEffectOfDiscontinuedOperation_2E9F3BA614D7EE1FA58F06E20A5B0B43" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DiscontinuedOperationTaxEffectOfDiscontinuedOperation_2E9F3BA614D7EE1FA58F06E20A5B0B43" xlink:to="lab_us-gaap_DiscontinuedOperationTaxEffectOfDiscontinuedOperation_2E9F3BA614D7EE1FA58F06E20A5B0B43" xlink:type="arc" />
    <link:label id="lab_us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTax_34EEEC77E6CB5027E90206E20A5C4CC8_totalLabel_en-US" xlink:label="lab_us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTax_34EEEC77E6CB5027E90206E20A5C4CC8" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Income from discontinued operations after income taxes</link:label>
    <link:label id="lab_us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTax_34EEEC77E6CB5027E90206E20A5C4CC8_label_en-US" xlink:label="lab_us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTax_34EEEC77E6CB5027E90206E20A5C4CC8" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Income (Loss) from Discontinued Operations, Net of Tax, Including Portion Attributable to Noncontrolling Interest</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTax" xlink:label="loc_us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTax_34EEEC77E6CB5027E90206E20A5C4CC8" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTax_34EEEC77E6CB5027E90206E20A5C4CC8" xlink:to="lab_us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTax_34EEEC77E6CB5027E90206E20A5C4CC8" xlink:type="arc" />
    <link:label id="lab_us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToNoncontrollingInterest_0AB61FA9681E53F22E6D06E20A5CEECC_terseLabel_en-US" xlink:label="lab_us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToNoncontrollingInterest_0AB61FA9681E53F22E6D06E20A5CEECC" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Less: Net income from discontinued operations attributable to noncontrolling interests</link:label>
    <link:label id="lab_us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToNoncontrollingInterest_0AB61FA9681E53F22E6D06E20A5CEECC_label_en-US" xlink:label="lab_us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToNoncontrollingInterest_0AB61FA9681E53F22E6D06E20A5CEECC" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Income (Loss) from Discontinued Operations, Net of Tax, Attributable to Noncontrolling Interest</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToNoncontrollingInterest" xlink:label="loc_us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToNoncontrollingInterest_0AB61FA9681E53F22E6D06E20A5CEECC" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToNoncontrollingInterest_0AB61FA9681E53F22E6D06E20A5CEECC" xlink:to="lab_us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToNoncontrollingInterest_0AB61FA9681E53F22E6D06E20A5CEECC" xlink:type="arc" />
    <link:label id="lab_us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity_67CC4F91FD9B98FA868C06E20A5C09DF_totalLabel_en-US" xlink:label="lab_us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity_67CC4F91FD9B98FA868C06E20A5C09DF" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Net income from discontinued operations</link:label>
    <link:label id="lab_us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity_67CC4F91FD9B98FA868C06E20A5C09DF_label_en-US" xlink:label="lab_us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity_67CC4F91FD9B98FA868C06E20A5C09DF" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Income (Loss) from Discontinued Operations, Net of Tax, Attributable to Parent</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity" xlink:label="loc_us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity_67CC4F91FD9B98FA868C06E20A5C09DF" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity_67CC4F91FD9B98FA868C06E20A5C09DF" xlink:to="lab_us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity_67CC4F91FD9B98FA868C06E20A5C09DF" xlink:type="arc" />
    <link:label id="lab_us-gaap_EquityAbstract_AE0BB5B9FBBA8060C95707196EDC673A_label_en-US" xlink:label="lab_us-gaap_EquityAbstract_AE0BB5B9FBBA8060C95707196EDC673A" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Equity [Abstract]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_EquityAbstract" xlink:label="loc_us-gaap_EquityAbstract_AE0BB5B9FBBA8060C95707196EDC673A" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_EquityAbstract_AE0BB5B9FBBA8060C95707196EDC673A" xlink:to="lab_us-gaap_EquityAbstract_AE0BB5B9FBBA8060C95707196EDC673A" xlink:type="arc" />
    <link:label id="lab_us-gaap_AccumulatedOtherComprehensiveIncomeLossTable_C94FA4A4D89D09197A1807196EDC76EB_terseLabel_en-US" xlink:label="lab_us-gaap_AccumulatedOtherComprehensiveIncomeLossTable_C94FA4A4D89D09197A1807196EDC76EB" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Accumulated Other Comprehensive Income (Loss) [Table]</link:label>
    <link:label id="lab_us-gaap_AccumulatedOtherComprehensiveIncomeLossTable_C94FA4A4D89D09197A1807196EDC76EB_label_en-US" xlink:label="lab_us-gaap_AccumulatedOtherComprehensiveIncomeLossTable_C94FA4A4D89D09197A1807196EDC76EB" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Accumulated Other Comprehensive Income (Loss) [Table]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AccumulatedOtherComprehensiveIncomeLossTable" xlink:label="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossTable_C94FA4A4D89D09197A1807196EDC76EB" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossTable_C94FA4A4D89D09197A1807196EDC76EB" xlink:to="lab_us-gaap_AccumulatedOtherComprehensiveIncomeLossTable_C94FA4A4D89D09197A1807196EDC76EB" xlink:type="arc" />
    <link:label id="lab_us-gaap_AdjustmentsForNewAccountingPronouncementsAxis_509D83FCF7C7D966208607196EDC895B_terseLabel_en-US" xlink:label="lab_us-gaap_AdjustmentsForNewAccountingPronouncementsAxis_509D83FCF7C7D966208607196EDC895B" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Adjustments for New Accounting Pronouncements [Axis]</link:label>
    <link:label id="lab_us-gaap_AdjustmentsForNewAccountingPronouncementsAxis_509D83FCF7C7D966208607196EDC895B_label_en-US" xlink:label="lab_us-gaap_AdjustmentsForNewAccountingPronouncementsAxis_509D83FCF7C7D966208607196EDC895B" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Adjustments for New Accounting Pronouncements [Axis]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AdjustmentsForNewAccountingPronouncementsAxis" xlink:label="loc_us-gaap_AdjustmentsForNewAccountingPronouncementsAxis_509D83FCF7C7D966208607196EDC895B" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AdjustmentsForNewAccountingPronouncementsAxis_509D83FCF7C7D966208607196EDC895B" xlink:to="lab_us-gaap_AdjustmentsForNewAccountingPronouncementsAxis_509D83FCF7C7D966208607196EDC895B" xlink:type="arc" />
    <link:label id="lab_us-gaap_TypeOfAdoptionMember_F818235DA25192D2870107196EDC3756_terseLabel_en-US" xlink:label="lab_us-gaap_TypeOfAdoptionMember_F818235DA25192D2870107196EDC3756" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Type of Adoption [Domain]</link:label>
    <link:label id="lab_us-gaap_TypeOfAdoptionMember_F818235DA25192D2870107196EDC3756_label_en-US" xlink:label="lab_us-gaap_TypeOfAdoptionMember_F818235DA25192D2870107196EDC3756" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Type of Adoption [Domain]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_TypeOfAdoptionMember" xlink:label="loc_us-gaap_TypeOfAdoptionMember_F818235DA25192D2870107196EDC3756" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_TypeOfAdoptionMember_F818235DA25192D2870107196EDC3756" xlink:to="lab_us-gaap_TypeOfAdoptionMember_F818235DA25192D2870107196EDC3756" xlink:type="arc" />
    <link:label id="lab_us-gaap_AccountingStandardsUpdate201707Member_CD52B26B467004AE609807196EDC64E0_terseLabel_en-US" xlink:label="lab_us-gaap_AccountingStandardsUpdate201707Member_CD52B26B467004AE609807196EDC64E0" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">ASU 2017-07</link:label>
    <link:label id="lab_us-gaap_AccountingStandardsUpdate201707Member_CD52B26B467004AE609807196EDC64E0_label_en-US" xlink:label="lab_us-gaap_AccountingStandardsUpdate201707Member_CD52B26B467004AE609807196EDC64E0" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Accounting Standards Update 2017-07 [Member]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AccountingStandardsUpdate201707Member" xlink:label="loc_us-gaap_AccountingStandardsUpdate201707Member_CD52B26B467004AE609807196EDC64E0" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AccountingStandardsUpdate201707Member_CD52B26B467004AE609807196EDC64E0" xlink:to="lab_us-gaap_AccountingStandardsUpdate201707Member_CD52B26B467004AE609807196EDC64E0" xlink:type="arc" />
    <link:label id="lab_us-gaap_AccountingStandardsUpdate201712Member_1D09D17C8CFCD976482207196EDCFAED_terseLabel_en-US" xlink:label="lab_us-gaap_AccountingStandardsUpdate201712Member_1D09D17C8CFCD976482207196EDCFAED" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">ASU 2017-12</link:label>
    <link:label id="lab_us-gaap_AccountingStandardsUpdate201712Member_1D09D17C8CFCD976482207196EDCFAED_label_en-US" xlink:label="lab_us-gaap_AccountingStandardsUpdate201712Member_1D09D17C8CFCD976482207196EDCFAED" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Accounting Standards Update 2017-12 [Member]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AccountingStandardsUpdate201712Member" xlink:label="loc_us-gaap_AccountingStandardsUpdate201712Member_1D09D17C8CFCD976482207196EDCFAED" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AccountingStandardsUpdate201712Member_1D09D17C8CFCD976482207196EDCFAED" xlink:to="lab_us-gaap_AccountingStandardsUpdate201712Member_1D09D17C8CFCD976482207196EDCFAED" xlink:type="arc" />
    <link:label id="lab_us-gaap_StatementEquityComponentsAxis_FAF19E6A8B33C8A80CF207196EDC8D62_terseLabel_en-US" xlink:label="lab_us-gaap_StatementEquityComponentsAxis_FAF19E6A8B33C8A80CF207196EDC8D62" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Equity Components [Axis]</link:label>
    <link:label id="lab_us-gaap_StatementEquityComponentsAxis_FAF19E6A8B33C8A80CF207196EDC8D62_label_en-US" xlink:label="lab_us-gaap_StatementEquityComponentsAxis_FAF19E6A8B33C8A80CF207196EDC8D62" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Equity Components [Axis]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_StatementEquityComponentsAxis" xlink:label="loc_us-gaap_StatementEquityComponentsAxis_FAF19E6A8B33C8A80CF207196EDC8D62" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_StatementEquityComponentsAxis_FAF19E6A8B33C8A80CF207196EDC8D62" xlink:to="lab_us-gaap_StatementEquityComponentsAxis_FAF19E6A8B33C8A80CF207196EDC8D62" xlink:type="arc" />
    <link:label id="lab_us-gaap_EquityComponentDomain_A2E1C43E340592461F2807196EDCA964_terseLabel_en-US" xlink:label="lab_us-gaap_EquityComponentDomain_A2E1C43E340592461F2807196EDCA964" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Equity Component [Domain]</link:label>
    <link:label id="lab_us-gaap_EquityComponentDomain_A2E1C43E340592461F2807196EDCA964_label_en-US" xlink:label="lab_us-gaap_EquityComponentDomain_A2E1C43E340592461F2807196EDCA964" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Equity Component [Domain]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_EquityComponentDomain" xlink:label="loc_us-gaap_EquityComponentDomain_A2E1C43E340592461F2807196EDCA964" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_EquityComponentDomain_A2E1C43E340592461F2807196EDCA964" xlink:to="lab_us-gaap_EquityComponentDomain_A2E1C43E340592461F2807196EDCA964" xlink:type="arc" />
    <link:label id="lab_us-gaap_AccumulatedOtherComprehensiveIncomeMember_7BDB8A44F342A370DB1C07196EDC56A5_verboseLabel_en-US" xlink:label="lab_us-gaap_AccumulatedOtherComprehensiveIncomeMember_7BDB8A44F342A370DB1C07196EDC56A5" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Arconic</link:label>
    <link:label id="lab_us-gaap_AccumulatedOtherComprehensiveIncomeMember_7BDB8A44F342A370DB1C07196EDC56A5_label_en-US" xlink:label="lab_us-gaap_AccumulatedOtherComprehensiveIncomeMember_7BDB8A44F342A370DB1C07196EDC56A5" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">AOCI Attributable to Parent [Member]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AccumulatedOtherComprehensiveIncomeMember" xlink:label="loc_us-gaap_AccumulatedOtherComprehensiveIncomeMember_7BDB8A44F342A370DB1C07196EDC56A5" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AccumulatedOtherComprehensiveIncomeMember_7BDB8A44F342A370DB1C07196EDC56A5" xlink:to="lab_us-gaap_AccumulatedOtherComprehensiveIncomeMember_7BDB8A44F342A370DB1C07196EDC56A5" xlink:type="arc" />
    <link:label id="lab_us-gaap_AccumulatedDefinedBenefitPlansAdjustmentMember_36C61A98C02F6EF8A0A607196EDC3D85_terseLabel_en-US" xlink:label="lab_us-gaap_AccumulatedDefinedBenefitPlansAdjustmentMember_36C61A98C02F6EF8A0A607196EDC3D85" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Pension and other postretirement benefits (G)</link:label>
    <link:label id="lab_us-gaap_AccumulatedDefinedBenefitPlansAdjustmentMember_36C61A98C02F6EF8A0A607196EDC3D85_label_en-US" xlink:label="lab_us-gaap_AccumulatedDefinedBenefitPlansAdjustmentMember_36C61A98C02F6EF8A0A607196EDC3D85" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Accumulated Defined Benefit Plans Adjustment Attributable to Parent [Member]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AccumulatedDefinedBenefitPlansAdjustmentMember" xlink:label="loc_us-gaap_AccumulatedDefinedBenefitPlansAdjustmentMember_36C61A98C02F6EF8A0A607196EDC3D85" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AccumulatedDefinedBenefitPlansAdjustmentMember_36C61A98C02F6EF8A0A607196EDC3D85" xlink:to="lab_us-gaap_AccumulatedDefinedBenefitPlansAdjustmentMember_36C61A98C02F6EF8A0A607196EDC3D85" xlink:type="arc" />
    <link:label id="lab_us-gaap_AccumulatedTranslationAdjustmentMember_5328E6EF2FBE6219757407196EDC5BF8_terseLabel_en-US" xlink:label="lab_us-gaap_AccumulatedTranslationAdjustmentMember_5328E6EF2FBE6219757407196EDC5BF8" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Foreign currency translation</link:label>
    <link:label id="lab_us-gaap_AccumulatedTranslationAdjustmentMember_5328E6EF2FBE6219757407196EDC5BF8_label_en-US" xlink:label="lab_us-gaap_AccumulatedTranslationAdjustmentMember_5328E6EF2FBE6219757407196EDC5BF8" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Accumulated Foreign Currency Adjustment Attributable to Parent [Member]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AccumulatedTranslationAdjustmentMember" xlink:label="loc_us-gaap_AccumulatedTranslationAdjustmentMember_5328E6EF2FBE6219757407196EDC5BF8" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AccumulatedTranslationAdjustmentMember_5328E6EF2FBE6219757407196EDC5BF8" xlink:to="lab_us-gaap_AccumulatedTranslationAdjustmentMember_5328E6EF2FBE6219757407196EDC5BF8" xlink:type="arc" />
    <link:label id="lab_us-gaap_AccumulatedNetUnrealizedInvestmentGainLossMember_E6C162FD6CAB1F88304B07196EE0F2CE_terseLabel_en-US" xlink:label="lab_us-gaap_AccumulatedNetUnrealizedInvestmentGainLossMember_E6C162FD6CAB1F88304B07196EE0F2CE" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Available-for-sale securities</link:label>
    <link:label id="lab_us-gaap_AccumulatedNetUnrealizedInvestmentGainLossMember_E6C162FD6CAB1F88304B07196EE0F2CE_label_en-US" xlink:label="lab_us-gaap_AccumulatedNetUnrealizedInvestmentGainLossMember_E6C162FD6CAB1F88304B07196EE0F2CE" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Accumulated Net Investment Gain (Loss) Attributable to Parent [Member]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AccumulatedNetUnrealizedInvestmentGainLossMember" xlink:label="loc_us-gaap_AccumulatedNetUnrealizedInvestmentGainLossMember_E6C162FD6CAB1F88304B07196EE0F2CE" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AccumulatedNetUnrealizedInvestmentGainLossMember_E6C162FD6CAB1F88304B07196EE0F2CE" xlink:to="lab_us-gaap_AccumulatedNetUnrealizedInvestmentGainLossMember_E6C162FD6CAB1F88304B07196EE0F2CE" xlink:type="arc" />
    <link:label id="lab_us-gaap_AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember_3CBD6E746E27CA03BF6507196EE02155_terseLabel_en-US" xlink:label="lab_us-gaap_AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember_3CBD6E746E27CA03BF6507196EE02155" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Cash flow hedges</link:label>
    <link:label id="lab_us-gaap_AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember_3CBD6E746E27CA03BF6507196EE02155_label_en-US" xlink:label="lab_us-gaap_AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember_3CBD6E746E27CA03BF6507196EE02155" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Accumulated Net Gain (Loss) from Cash Flow Hedges Attributable to Parent [Member]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember" xlink:label="loc_us-gaap_AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember_3CBD6E746E27CA03BF6507196EE02155" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember_3CBD6E746E27CA03BF6507196EE02155" xlink:to="lab_us-gaap_AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember_3CBD6E746E27CA03BF6507196EE02155" xlink:type="arc" />
    <link:label id="lab_us-gaap_AociAttributableToNoncontrollingInterestMember_DEBB070CE8DE5A07786207196EE02227_terseLabel_en-US" xlink:label="lab_us-gaap_AociAttributableToNoncontrollingInterestMember_DEBB070CE8DE5A07786207196EE02227" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Noncontrolling Interests</link:label>
    <link:label id="lab_us-gaap_AociAttributableToNoncontrollingInterestMember_DEBB070CE8DE5A07786207196EE02227_label_en-US" xlink:label="lab_us-gaap_AociAttributableToNoncontrollingInterestMember_DEBB070CE8DE5A07786207196EE02227" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">AOCI Attributable to Noncontrolling Interest [Member]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AociAttributableToNoncontrollingInterestMember" xlink:label="loc_us-gaap_AociAttributableToNoncontrollingInterestMember_DEBB070CE8DE5A07786207196EE02227" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AociAttributableToNoncontrollingInterestMember_DEBB070CE8DE5A07786207196EE02227" xlink:to="lab_us-gaap_AociAttributableToNoncontrollingInterestMember_DEBB070CE8DE5A07786207196EE02227" xlink:type="arc" />
    <link:label id="lab_us-gaap_AccumulatedDefinedBenefitPlansAdjustmentAttributableToNoncontrollingInterestMember_B4B19F925BBDB366E39407196EE05552_terseLabel_en-US" xlink:label="lab_us-gaap_AccumulatedDefinedBenefitPlansAdjustmentAttributableToNoncontrollingInterestMember_B4B19F925BBDB366E39407196EE05552" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Pension and other postretirement benefits (G)</link:label>
    <link:label id="lab_us-gaap_AccumulatedDefinedBenefitPlansAdjustmentAttributableToNoncontrollingInterestMember_B4B19F925BBDB366E39407196EE05552_label_en-US" xlink:label="lab_us-gaap_AccumulatedDefinedBenefitPlansAdjustmentAttributableToNoncontrollingInterestMember_B4B19F925BBDB366E39407196EE05552" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Accumulated Defined Benefit Plans Adjustment Attributable to Noncontrolling Interest [Member]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AccumulatedDefinedBenefitPlansAdjustmentAttributableToNoncontrollingInterestMember" xlink:label="loc_us-gaap_AccumulatedDefinedBenefitPlansAdjustmentAttributableToNoncontrollingInterestMember_B4B19F925BBDB366E39407196EE05552" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AccumulatedDefinedBenefitPlansAdjustmentAttributableToNoncontrollingInterestMember_B4B19F925BBDB366E39407196EE05552" xlink:to="lab_us-gaap_AccumulatedDefinedBenefitPlansAdjustmentAttributableToNoncontrollingInterestMember_B4B19F925BBDB366E39407196EE05552" xlink:type="arc" />
    <link:label id="lab_us-gaap_AccumulatedForeignCurrencyAdjustmentAttributableToNoncontrollingInterestMember_CE46E19F4E9B88C17ADF07196EE0CEB5_terseLabel_en-US" xlink:label="lab_us-gaap_AccumulatedForeignCurrencyAdjustmentAttributableToNoncontrollingInterestMember_CE46E19F4E9B88C17ADF07196EE0CEB5" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Foreign currency translation</link:label>
    <link:label id="lab_us-gaap_AccumulatedForeignCurrencyAdjustmentAttributableToNoncontrollingInterestMember_CE46E19F4E9B88C17ADF07196EE0CEB5_label_en-US" xlink:label="lab_us-gaap_AccumulatedForeignCurrencyAdjustmentAttributableToNoncontrollingInterestMember_CE46E19F4E9B88C17ADF07196EE0CEB5" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Accumulated Foreign Currency Adjustment Attributable to Noncontrolling Interest [Member]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AccumulatedForeignCurrencyAdjustmentAttributableToNoncontrollingInterestMember" xlink:label="loc_us-gaap_AccumulatedForeignCurrencyAdjustmentAttributableToNoncontrollingInterestMember_CE46E19F4E9B88C17ADF07196EE0CEB5" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AccumulatedForeignCurrencyAdjustmentAttributableToNoncontrollingInterestMember_CE46E19F4E9B88C17ADF07196EE0CEB5" xlink:to="lab_us-gaap_AccumulatedForeignCurrencyAdjustmentAttributableToNoncontrollingInterestMember_CE46E19F4E9B88C17ADF07196EE0CEB5" xlink:type="arc" />
    <link:label id="lab_us-gaap_AccumulatedNetInvestmentGainLossAttributableToNoncontrollingInterestMember_8BA1516EFABD3996BBB107196EE0E425_terseLabel_en-US" xlink:label="lab_us-gaap_AccumulatedNetInvestmentGainLossAttributableToNoncontrollingInterestMember_8BA1516EFABD3996BBB107196EE0E425" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Available-for-sale securities</link:label>
    <link:label id="lab_us-gaap_AccumulatedNetInvestmentGainLossAttributableToNoncontrollingInterestMember_8BA1516EFABD3996BBB107196EE0E425_label_en-US" xlink:label="lab_us-gaap_AccumulatedNetInvestmentGainLossAttributableToNoncontrollingInterestMember_8BA1516EFABD3996BBB107196EE0E425" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Accumulated Net Investment Gain (Loss) Attributable to Noncontrolling Interest [Member]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AccumulatedNetInvestmentGainLossAttributableToNoncontrollingInterestMember" xlink:label="loc_us-gaap_AccumulatedNetInvestmentGainLossAttributableToNoncontrollingInterestMember_8BA1516EFABD3996BBB107196EE0E425" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AccumulatedNetInvestmentGainLossAttributableToNoncontrollingInterestMember_8BA1516EFABD3996BBB107196EE0E425" xlink:to="lab_us-gaap_AccumulatedNetInvestmentGainLossAttributableToNoncontrollingInterestMember_8BA1516EFABD3996BBB107196EE0E425" xlink:type="arc" />
    <link:label id="lab_us-gaap_AccumulatedNetGainLossFromCashFlowHedgesAttributableToNoncontrollingInterestMember_73BF3B10E24D27FE2F6D07196EE095B2_terseLabel_en-US" xlink:label="lab_us-gaap_AccumulatedNetGainLossFromCashFlowHedgesAttributableToNoncontrollingInterestMember_73BF3B10E24D27FE2F6D07196EE095B2" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Cash flow hedges</link:label>
    <link:label id="lab_us-gaap_AccumulatedNetGainLossFromCashFlowHedgesAttributableToNoncontrollingInterestMember_73BF3B10E24D27FE2F6D07196EE095B2_label_en-US" xlink:label="lab_us-gaap_AccumulatedNetGainLossFromCashFlowHedgesAttributableToNoncontrollingInterestMember_73BF3B10E24D27FE2F6D07196EE095B2" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Accumulated Net Gain (Loss) from Cash Flow Hedges Attributable to Noncontrolling Interest [Member]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AccumulatedNetGainLossFromCashFlowHedgesAttributableToNoncontrollingInterestMember" xlink:label="loc_us-gaap_AccumulatedNetGainLossFromCashFlowHedgesAttributableToNoncontrollingInterestMember_73BF3B10E24D27FE2F6D07196EE095B2" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AccumulatedNetGainLossFromCashFlowHedgesAttributableToNoncontrollingInterestMember_73BF3B10E24D27FE2F6D07196EE095B2" xlink:to="lab_us-gaap_AccumulatedNetGainLossFromCashFlowHedgesAttributableToNoncontrollingInterestMember_73BF3B10E24D27FE2F6D07196EE095B2" xlink:type="arc" />
    <link:label id="lab_us-gaap_DerivativeInstrumentRiskAxis_3FEB54B72F7BBB4D79AA07196EE00F8B_terseLabel_en-US" xlink:label="lab_us-gaap_DerivativeInstrumentRiskAxis_3FEB54B72F7BBB4D79AA07196EE00F8B" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Derivative Instrument [Axis]</link:label>
    <link:label id="lab_us-gaap_DerivativeInstrumentRiskAxis_3FEB54B72F7BBB4D79AA07196EE00F8B_label_en-US" xlink:label="lab_us-gaap_DerivativeInstrumentRiskAxis_3FEB54B72F7BBB4D79AA07196EE00F8B" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Derivative Instrument [Axis]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DerivativeInstrumentRiskAxis" xlink:label="loc_us-gaap_DerivativeInstrumentRiskAxis_3FEB54B72F7BBB4D79AA07196EE00F8B" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_3FEB54B72F7BBB4D79AA07196EE00F8B" xlink:to="lab_us-gaap_DerivativeInstrumentRiskAxis_3FEB54B72F7BBB4D79AA07196EE00F8B" xlink:type="arc" />
    <link:label id="lab_us-gaap_DerivativeContractTypeDomain_7142A3744A838700349907196EE03894_terseLabel_en-US" xlink:label="lab_us-gaap_DerivativeContractTypeDomain_7142A3744A838700349907196EE03894" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Derivative Contract [Domain]</link:label>
    <link:label id="lab_us-gaap_DerivativeContractTypeDomain_7142A3744A838700349907196EE03894_label_en-US" xlink:label="lab_us-gaap_DerivativeContractTypeDomain_7142A3744A838700349907196EE03894" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Derivative Contract [Domain]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DerivativeContractTypeDomain" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_7142A3744A838700349907196EE03894" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_7142A3744A838700349907196EE03894" xlink:to="lab_us-gaap_DerivativeContractTypeDomain_7142A3744A838700349907196EE03894" xlink:type="arc" />
    <link:label id="lab_arnc_AluminumContractsMember_DB09F9D8A5D7E299078207196EE05427_terseLabel_en-US" xlink:label="lab_arnc_AluminumContractsMember_DB09F9D8A5D7E299078207196EE05427" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Aluminum Contracts</link:label>
    <link:label id="lab_arnc_AluminumContractsMember_DB09F9D8A5D7E299078207196EE05427_label_en-US" xlink:label="lab_arnc_AluminumContractsMember_DB09F9D8A5D7E299078207196EE05427" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Aluminum Contracts [Member]</link:label>
    <link:label id="lab_arnc_AluminumContractsMember_DB09F9D8A5D7E299078207196EE05427_documentation_en-US" xlink:label="lab_arnc_AluminumContractsMember_DB09F9D8A5D7E299078207196EE05427" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Aluminum contracts.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_AluminumContractsMember" xlink:label="loc_arnc_AluminumContractsMember_DB09F9D8A5D7E299078207196EE05427" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_AluminumContractsMember_DB09F9D8A5D7E299078207196EE05427" xlink:to="lab_arnc_AluminumContractsMember_DB09F9D8A5D7E299078207196EE05427" xlink:type="arc" />
    <link:label id="lab_us-gaap_EnergyRelatedDerivativeMember_94F6F0715C91A4D949B207196EE02E22_terseLabel_en-US" xlink:label="lab_us-gaap_EnergyRelatedDerivativeMember_94F6F0715C91A4D949B207196EE02E22" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Energy Contracts</link:label>
    <link:label id="lab_us-gaap_EnergyRelatedDerivativeMember_94F6F0715C91A4D949B207196EE02E22_label_en-US" xlink:label="lab_us-gaap_EnergyRelatedDerivativeMember_94F6F0715C91A4D949B207196EE02E22" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Energy Related Derivative [Member]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_EnergyRelatedDerivativeMember" xlink:label="loc_us-gaap_EnergyRelatedDerivativeMember_94F6F0715C91A4D949B207196EE02E22" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_EnergyRelatedDerivativeMember_94F6F0715C91A4D949B207196EE02E22" xlink:to="lab_us-gaap_EnergyRelatedDerivativeMember_94F6F0715C91A4D949B207196EE02E22" xlink:type="arc" />
    <link:label id="lab_us-gaap_InterestRateContractMember_93BE093F966DCEF0DAF607196EE0B5AC_terseLabel_en-US" xlink:label="lab_us-gaap_InterestRateContractMember_93BE093F966DCEF0DAF607196EE0B5AC" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Interest Rate Contracts</link:label>
    <link:label id="lab_us-gaap_InterestRateContractMember_93BE093F966DCEF0DAF607196EE0B5AC_label_en-US" xlink:label="lab_us-gaap_InterestRateContractMember_93BE093F966DCEF0DAF607196EE0B5AC" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Interest Rate Contract [Member]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_InterestRateContractMember" xlink:label="loc_us-gaap_InterestRateContractMember_93BE093F966DCEF0DAF607196EE0B5AC" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_InterestRateContractMember_93BE093F966DCEF0DAF607196EE0B5AC" xlink:to="lab_us-gaap_InterestRateContractMember_93BE093F966DCEF0DAF607196EE0B5AC" xlink:type="arc" />
    <link:label id="lab_arnc_NickelContractsMember_2806D7CDE1B040FE4FC707196EE0D77A_terseLabel_en-US" xlink:label="lab_arnc_NickelContractsMember_2806D7CDE1B040FE4FC707196EE0D77A" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Nickel Contracts</link:label>
    <link:label id="lab_arnc_NickelContractsMember_2806D7CDE1B040FE4FC707196EE0D77A_label_en-US" xlink:label="lab_arnc_NickelContractsMember_2806D7CDE1B040FE4FC707196EE0D77A" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Nickel Contracts [Member]</link:label>
    <link:label id="lab_arnc_NickelContractsMember_2806D7CDE1B040FE4FC707196EE0D77A_documentation_en-US" xlink:label="lab_arnc_NickelContractsMember_2806D7CDE1B040FE4FC707196EE0D77A" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Nickel Contracts [Member]</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_NickelContractsMember" xlink:label="loc_arnc_NickelContractsMember_2806D7CDE1B040FE4FC707196EE0D77A" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_NickelContractsMember_2806D7CDE1B040FE4FC707196EE0D77A" xlink:to="lab_arnc_NickelContractsMember_2806D7CDE1B040FE4FC707196EE0D77A" xlink:type="arc" />
    <link:label id="lab_us-gaap_AccumulatedOtherComprehensiveIncomeLossLineItems_F7E84253B628E49150B207196EE07061_terseLabel_en-US" xlink:label="lab_us-gaap_AccumulatedOtherComprehensiveIncomeLossLineItems_F7E84253B628E49150B207196EE07061" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Accumulated Other Comprehensive Income (Loss) [Line Items]</link:label>
    <link:label id="lab_us-gaap_AccumulatedOtherComprehensiveIncomeLossLineItems_F7E84253B628E49150B207196EE07061_label_en-US" xlink:label="lab_us-gaap_AccumulatedOtherComprehensiveIncomeLossLineItems_F7E84253B628E49150B207196EE07061" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Accumulated Other Comprehensive Income (Loss) [Line Items]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AccumulatedOtherComprehensiveIncomeLossLineItems" xlink:label="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossLineItems_F7E84253B628E49150B207196EE07061" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossLineItems_F7E84253B628E49150B207196EE07061" xlink:to="lab_us-gaap_AccumulatedOtherComprehensiveIncomeLossLineItems_F7E84253B628E49150B207196EE07061" xlink:type="arc" />
    <link:label id="lab_us-gaap_ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTaxAbstract_43FF264C48772E2A7E4007196EE0F3C1_terseLabel_en-US" xlink:label="lab_us-gaap_ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTaxAbstract_43FF264C48772E2A7E4007196EE0F3C1" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]</link:label>
    <link:label id="lab_us-gaap_ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTaxAbstract_43FF264C48772E2A7E4007196EE0F3C1_label_en-US" xlink:label="lab_us-gaap_ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTaxAbstract_43FF264C48772E2A7E4007196EE0F3C1" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTaxAbstract" xlink:label="loc_us-gaap_ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTaxAbstract_43FF264C48772E2A7E4007196EE0F3C1" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTaxAbstract_43FF264C48772E2A7E4007196EE0F3C1" xlink:to="lab_us-gaap_ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTaxAbstract_43FF264C48772E2A7E4007196EE0F3C1" xlink:type="arc" />
    <link:label id="lab_us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest_6222BBC92D876BC4245907196EE05C6D_periodStartLabel_en-US" xlink:label="lab_us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest_6222BBC92D876BC4245907196EE05C6D" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel" xlink:type="resource" xml:lang="en-US">Balance at beginning of period</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest" xlink:label="loc_us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest_6222BBC92D876BC4245907196EE05C6D" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest_6222BBC92D876BC4245907196EE05C6D" xlink:to="lab_us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest_6222BBC92D876BC4245907196EE05C6D" xlink:type="arc" />
    <link:label id="lab_us-gaap_CumulativeEffectOfNewAccountingPrincipleInPeriodOfAdoption_9E98D38FFBF8FFF1B94B07196EE0EA9A_terseLabel_en-US" xlink:label="lab_us-gaap_CumulativeEffectOfNewAccountingPrincipleInPeriodOfAdoption_9E98D38FFBF8FFF1B94B07196EE0EA9A" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Adoption of accounting standard (A)</link:label>
    <link:label id="lab_us-gaap_CumulativeEffectOfNewAccountingPrincipleInPeriodOfAdoption_9E98D38FFBF8FFF1B94B07196EE0EA9A_label_en-US" xlink:label="lab_us-gaap_CumulativeEffectOfNewAccountingPrincipleInPeriodOfAdoption_9E98D38FFBF8FFF1B94B07196EE0EA9A" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Cumulative Effect of New Accounting Principle in Period of Adoption</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_CumulativeEffectOfNewAccountingPrincipleInPeriodOfAdoption" xlink:label="loc_us-gaap_CumulativeEffectOfNewAccountingPrincipleInPeriodOfAdoption_9E98D38FFBF8FFF1B94B07196EE0EA9A" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CumulativeEffectOfNewAccountingPrincipleInPeriodOfAdoption_9E98D38FFBF8FFF1B94B07196EE0EA9A" xlink:to="lab_us-gaap_CumulativeEffectOfNewAccountingPrincipleInPeriodOfAdoption_9E98D38FFBF8FFF1B94B07196EE0EA9A" xlink:type="arc" />
    <link:label id="lab_us-gaap_OtherComprehensiveIncomeLossBeforeReclassificationsBeforeTax_A0A72FB260041D82B98507196EE8800F_terseLabel_en-US" xlink:label="lab_us-gaap_OtherComprehensiveIncomeLossBeforeReclassificationsBeforeTax_A0A72FB260041D82B98507196EE8800F" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Other comprehensive income (loss), before reclassifications, before tax</link:label>
    <link:label id="lab_us-gaap_OtherComprehensiveIncomeLossBeforeReclassificationsBeforeTax_A0A72FB260041D82B98507196EE8800F_label_en-US" xlink:label="lab_us-gaap_OtherComprehensiveIncomeLossBeforeReclassificationsBeforeTax_A0A72FB260041D82B98507196EE8800F" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Other Comprehensive Income (Loss), before Reclassifications, before Tax</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_OtherComprehensiveIncomeLossBeforeReclassificationsBeforeTax" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossBeforeReclassificationsBeforeTax_A0A72FB260041D82B98507196EE8800F" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OtherComprehensiveIncomeLossBeforeReclassificationsBeforeTax_A0A72FB260041D82B98507196EE8800F" xlink:to="lab_us-gaap_OtherComprehensiveIncomeLossBeforeReclassificationsBeforeTax_A0A72FB260041D82B98507196EE8800F" xlink:type="arc" />
    <link:label id="lab_us-gaap_OtherComprehensiveIncomeLossBeforeReclassificationsTax_610622AD8CEE919B00C707196EE8E97F_negatedTerseLabel_en-US" xlink:label="lab_us-gaap_OtherComprehensiveIncomeLossBeforeReclassificationsTax_610622AD8CEE919B00C707196EE8E97F" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:type="resource" xml:lang="en-US">Other comprehensive income (loss) before reclassifications, tax benefit (expense)</link:label>
    <link:label id="lab_us-gaap_OtherComprehensiveIncomeLossBeforeReclassificationsTax_610622AD8CEE919B00C707196EE8E97F_label_en-US" xlink:label="lab_us-gaap_OtherComprehensiveIncomeLossBeforeReclassificationsTax_610622AD8CEE919B00C707196EE8E97F" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Other Comprehensive Income (Loss) before Reclassifications, Tax</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_OtherComprehensiveIncomeLossBeforeReclassificationsTax" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossBeforeReclassificationsTax_610622AD8CEE919B00C707196EE8E97F" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OtherComprehensiveIncomeLossBeforeReclassificationsTax_610622AD8CEE919B00C707196EE8E97F" xlink:to="lab_us-gaap_OtherComprehensiveIncomeLossBeforeReclassificationsTax_610622AD8CEE919B00C707196EE8E97F" xlink:type="arc" />
    <link:label id="lab_us-gaap_OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax_313A486BBB314A6AC81207196EE896F0_totalLabel_en-US" xlink:label="lab_us-gaap_OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax_313A486BBB314A6AC81207196EE896F0" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Total other comprehensive (loss) income before reclassifications, net of tax</link:label>
    <link:label id="lab_us-gaap_OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax_313A486BBB314A6AC81207196EE896F0_label_en-US" xlink:label="lab_us-gaap_OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax_313A486BBB314A6AC81207196EE896F0" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Other Comprehensive Income (Loss), before Reclassifications, Net of Tax</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax_313A486BBB314A6AC81207196EE896F0" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax_313A486BBB314A6AC81207196EE896F0" xlink:to="lab_us-gaap_OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax_313A486BBB314A6AC81207196EE896F0" xlink:type="arc" />
    <link:label id="lab_us-gaap_ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodBeforeTax_9DE1B66F02B57368E86807196EE82613_negatedTerseLabel_en-US" xlink:label="lab_us-gaap_ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodBeforeTax_9DE1B66F02B57368E86807196EE82613" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:type="resource" xml:lang="en-US">Reclassification from accumulated other comprehensive income, before tax</link:label>
    <link:label id="lab_us-gaap_ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodBeforeTax_9DE1B66F02B57368E86807196EE82613_label_en-US" xlink:label="lab_us-gaap_ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodBeforeTax_9DE1B66F02B57368E86807196EE82613" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Reclassification from Accumulated Other Comprehensive Income, Current Period, before Tax</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodBeforeTax" xlink:label="loc_us-gaap_ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodBeforeTax_9DE1B66F02B57368E86807196EE82613" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodBeforeTax_9DE1B66F02B57368E86807196EE82613" xlink:to="lab_us-gaap_ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodBeforeTax_9DE1B66F02B57368E86807196EE82613" xlink:type="arc" />
    <link:label id="lab_us-gaap_ReclassificationFromAociCurrentPeriodTax_0BF7138ACE103B7C200A07196EE8E098_terseLabel_en-US" xlink:label="lab_us-gaap_ReclassificationFromAociCurrentPeriodTax_0BF7138ACE103B7C200A07196EE8E098" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Reclassification from AOCI, tax benefit (expense)</link:label>
    <link:label id="lab_us-gaap_ReclassificationFromAociCurrentPeriodTax_0BF7138ACE103B7C200A07196EE8E098_label_en-US" xlink:label="lab_us-gaap_ReclassificationFromAociCurrentPeriodTax_0BF7138ACE103B7C200A07196EE8E098" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Reclassification from AOCI, Current Period, Tax</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ReclassificationFromAociCurrentPeriodTax" xlink:label="loc_us-gaap_ReclassificationFromAociCurrentPeriodTax_0BF7138ACE103B7C200A07196EE8E098" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ReclassificationFromAociCurrentPeriodTax_0BF7138ACE103B7C200A07196EE8E098" xlink:to="lab_us-gaap_ReclassificationFromAociCurrentPeriodTax_0BF7138ACE103B7C200A07196EE8E098" xlink:type="arc" />
    <link:label id="lab_us-gaap_ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax_B1C2793F9D38A93E444007196EE86AC4_negatedTotalLabel_en-US" xlink:label="lab_us-gaap_ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax_B1C2793F9D38A93E444007196EE86AC4" xlink:role="http://www.xbrl.org/2009/role/negatedTotalLabel" xlink:type="resource" xml:lang="en-US">Total amount reclassified from accumulated other comprehensive loss, net of tax</link:label>
    <link:label id="lab_us-gaap_ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax_B1C2793F9D38A93E444007196EE86AC4_label_en-US" xlink:label="lab_us-gaap_ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax_B1C2793F9D38A93E444007196EE86AC4" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax" xlink:label="loc_us-gaap_ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax_B1C2793F9D38A93E444007196EE86AC4" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax_B1C2793F9D38A93E444007196EE86AC4" xlink:to="lab_us-gaap_ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax_B1C2793F9D38A93E444007196EE86AC4" xlink:type="arc" />
    <link:label id="lab_us-gaap_OtherComprehensiveIncomeLossNetOfTax_07D36C4825265CEDB79D07196EE8ABB4_totalLabel_en-US" xlink:label="lab_us-gaap_OtherComprehensiveIncomeLossNetOfTax_07D36C4825265CEDB79D07196EE8ABB4" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Total Other comprehensive income (loss), net of tax</link:label>
    <link:label id="lab_us-gaap_OtherComprehensiveIncomeLossNetOfTax_07D36C4825265CEDB79D07196EE8ABB4_label_en-US" xlink:label="lab_us-gaap_OtherComprehensiveIncomeLossNetOfTax_07D36C4825265CEDB79D07196EE8ABB4" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Other Comprehensive Income (Loss), Net of Tax</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_OtherComprehensiveIncomeLossNetOfTax" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTax_07D36C4825265CEDB79D07196EE8ABB4" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTax_07D36C4825265CEDB79D07196EE8ABB4" xlink:to="lab_us-gaap_OtherComprehensiveIncomeLossNetOfTax_07D36C4825265CEDB79D07196EE8ABB4" xlink:type="arc" />
    <link:label id="lab_arnc_OtherComprehensiveIncomeLossAdjustmentTransferredToDiscontinuedOperations_F2B41603475FF305AD5E07196EE88417_terseLabel_en-US" xlink:label="lab_arnc_OtherComprehensiveIncomeLossAdjustmentTransferredToDiscontinuedOperations_F2B41603475FF305AD5E07196EE88417" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Transfer to Alcoa Corporation</link:label>
    <link:label id="lab_arnc_OtherComprehensiveIncomeLossAdjustmentTransferredToDiscontinuedOperations_F2B41603475FF305AD5E07196EE88417_label_en-US" xlink:label="lab_arnc_OtherComprehensiveIncomeLossAdjustmentTransferredToDiscontinuedOperations_F2B41603475FF305AD5E07196EE88417" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Other Comprehensive Income (Loss), Adjustment Transferred To Discontinued Operations</link:label>
    <link:label id="lab_arnc_OtherComprehensiveIncomeLossAdjustmentTransferredToDiscontinuedOperations_F2B41603475FF305AD5E07196EE88417_documentation_en-US" xlink:label="lab_arnc_OtherComprehensiveIncomeLossAdjustmentTransferredToDiscontinuedOperations_F2B41603475FF305AD5E07196EE88417" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Other comprehensive income loss adjustment transferred to discontinued operations.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_OtherComprehensiveIncomeLossAdjustmentTransferredToDiscontinuedOperations" xlink:label="loc_arnc_OtherComprehensiveIncomeLossAdjustmentTransferredToDiscontinuedOperations_F2B41603475FF305AD5E07196EE88417" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_OtherComprehensiveIncomeLossAdjustmentTransferredToDiscontinuedOperations_F2B41603475FF305AD5E07196EE88417" xlink:to="lab_arnc_OtherComprehensiveIncomeLossAdjustmentTransferredToDiscontinuedOperations_F2B41603475FF305AD5E07196EE88417" xlink:type="arc" />
    <link:label id="lab_us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest_ED288E5216F5551997EC07196EE88EF7_periodEndLabel_en-US" xlink:label="lab_us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest_ED288E5216F5551997EC07196EE88EF7" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel" xlink:type="resource" xml:lang="en-US">Balance at end of period</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest" xlink:label="loc_us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest_ED288E5216F5551997EC07196EE88EF7" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest_ED288E5216F5551997EC07196EE88EF7" xlink:to="lab_us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest_ED288E5216F5551997EC07196EE88EF7" xlink:type="arc" />
    <link:label id="lab_us-gaap_AccountingPoliciesAbstract_00EF69E8B1CE48B53B13EE536DD6884A_label_en-US" xlink:label="lab_us-gaap_AccountingPoliciesAbstract_00EF69E8B1CE48B53B13EE536DD6884A" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Accounting Policies [Abstract]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AccountingPoliciesAbstract" xlink:label="loc_us-gaap_AccountingPoliciesAbstract_00EF69E8B1CE48B53B13EE536DD6884A" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AccountingPoliciesAbstract_00EF69E8B1CE48B53B13EE536DD6884A" xlink:to="lab_us-gaap_AccountingPoliciesAbstract_00EF69E8B1CE48B53B13EE536DD6884A" xlink:type="arc" />
    <link:label id="lab_us-gaap_BasisOfAccountingPolicyPolicyTextBlock_DE53597AAD8B5952BC18EE536DD629D9_terseLabel_en-US" xlink:label="lab_us-gaap_BasisOfAccountingPolicyPolicyTextBlock_DE53597AAD8B5952BC18EE536DD629D9" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Basis of presentation</link:label>
    <link:label id="lab_us-gaap_BasisOfAccountingPolicyPolicyTextBlock_DE53597AAD8B5952BC18EE536DD629D9_label_en-US" xlink:label="lab_us-gaap_BasisOfAccountingPolicyPolicyTextBlock_DE53597AAD8B5952BC18EE536DD629D9" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Basis of Accounting, Policy [Policy Text Block]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_BasisOfAccountingPolicyPolicyTextBlock" xlink:label="loc_us-gaap_BasisOfAccountingPolicyPolicyTextBlock_DE53597AAD8B5952BC18EE536DD629D9" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_BasisOfAccountingPolicyPolicyTextBlock_DE53597AAD8B5952BC18EE536DD629D9" xlink:to="lab_us-gaap_BasisOfAccountingPolicyPolicyTextBlock_DE53597AAD8B5952BC18EE536DD629D9" xlink:type="arc" />
    <link:label id="lab_us-gaap_ConsolidationPolicyTextBlock_883745D2F268965F3E63EE536DD65D8A_terseLabel_en-US" xlink:label="lab_us-gaap_ConsolidationPolicyTextBlock_883745D2F268965F3E63EE536DD65D8A" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Principles of consolidation</link:label>
    <link:label id="lab_us-gaap_ConsolidationPolicyTextBlock_883745D2F268965F3E63EE536DD65D8A_label_en-US" xlink:label="lab_us-gaap_ConsolidationPolicyTextBlock_883745D2F268965F3E63EE536DD65D8A" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Consolidation, Policy [Policy Text Block]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ConsolidationPolicyTextBlock" xlink:label="loc_us-gaap_ConsolidationPolicyTextBlock_883745D2F268965F3E63EE536DD65D8A" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ConsolidationPolicyTextBlock_883745D2F268965F3E63EE536DD65D8A" xlink:to="lab_us-gaap_ConsolidationPolicyTextBlock_883745D2F268965F3E63EE536DD65D8A" xlink:type="arc" />
    <link:label id="lab_us-gaap_CashAndCashEquivalentsPolicyTextBlock_316CF2F9C89E13082766EE536DD74D3F_terseLabel_en-US" xlink:label="lab_us-gaap_CashAndCashEquivalentsPolicyTextBlock_316CF2F9C89E13082766EE536DD74D3F" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Cash equivalents</link:label>
    <link:label id="lab_us-gaap_CashAndCashEquivalentsPolicyTextBlock_316CF2F9C89E13082766EE536DD74D3F_label_en-US" xlink:label="lab_us-gaap_CashAndCashEquivalentsPolicyTextBlock_316CF2F9C89E13082766EE536DD74D3F" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Cash and Cash Equivalents, Policy [Policy Text Block]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_CashAndCashEquivalentsPolicyTextBlock" xlink:label="loc_us-gaap_CashAndCashEquivalentsPolicyTextBlock_316CF2F9C89E13082766EE536DD74D3F" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CashAndCashEquivalentsPolicyTextBlock_316CF2F9C89E13082766EE536DD74D3F" xlink:to="lab_us-gaap_CashAndCashEquivalentsPolicyTextBlock_316CF2F9C89E13082766EE536DD74D3F" xlink:type="arc" />
    <link:label id="lab_us-gaap_InventoryPolicyTextBlock_CB6541D2DA7F0E1FA5A9EE536DD7D8DB_terseLabel_en-US" xlink:label="lab_us-gaap_InventoryPolicyTextBlock_CB6541D2DA7F0E1FA5A9EE536DD7D8DB" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Inventory valuation</link:label>
    <link:label id="lab_us-gaap_InventoryPolicyTextBlock_CB6541D2DA7F0E1FA5A9EE536DD7D8DB_label_en-US" xlink:label="lab_us-gaap_InventoryPolicyTextBlock_CB6541D2DA7F0E1FA5A9EE536DD7D8DB" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Inventory, Policy [Policy Text Block]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_InventoryPolicyTextBlock" xlink:label="loc_us-gaap_InventoryPolicyTextBlock_CB6541D2DA7F0E1FA5A9EE536DD7D8DB" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_InventoryPolicyTextBlock_CB6541D2DA7F0E1FA5A9EE536DD7D8DB" xlink:to="lab_us-gaap_InventoryPolicyTextBlock_CB6541D2DA7F0E1FA5A9EE536DD7D8DB" xlink:type="arc" />
    <link:label id="lab_us-gaap_PropertyPlantAndEquipmentPolicyTextBlock_EF6D5A20198A942A0957EE536DD73A56_terseLabel_en-US" xlink:label="lab_us-gaap_PropertyPlantAndEquipmentPolicyTextBlock_EF6D5A20198A942A0957EE536DD73A56" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Properties, plants, and equipment</link:label>
    <link:label id="lab_us-gaap_PropertyPlantAndEquipmentPolicyTextBlock_EF6D5A20198A942A0957EE536DD73A56_label_en-US" xlink:label="lab_us-gaap_PropertyPlantAndEquipmentPolicyTextBlock_EF6D5A20198A942A0957EE536DD73A56" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Property, Plant and Equipment, Policy [Policy Text Block]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PropertyPlantAndEquipmentPolicyTextBlock" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentPolicyTextBlock_EF6D5A20198A942A0957EE536DD73A56" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentPolicyTextBlock_EF6D5A20198A942A0957EE536DD73A56" xlink:to="lab_us-gaap_PropertyPlantAndEquipmentPolicyTextBlock_EF6D5A20198A942A0957EE536DD73A56" xlink:type="arc" />
    <link:label id="lab_us-gaap_GoodwillAndIntangibleAssetsPolicyTextBlock_AFE87DC89BBA0CE817C1EE536DD724DF_terseLabel_en-US" xlink:label="lab_us-gaap_GoodwillAndIntangibleAssetsPolicyTextBlock_AFE87DC89BBA0CE817C1EE536DD724DF" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Goodwill and other intangible assets</link:label>
    <link:label id="lab_us-gaap_GoodwillAndIntangibleAssetsPolicyTextBlock_AFE87DC89BBA0CE817C1EE536DD724DF_label_en-US" xlink:label="lab_us-gaap_GoodwillAndIntangibleAssetsPolicyTextBlock_AFE87DC89BBA0CE817C1EE536DD724DF" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Goodwill and Intangible Assets, Policy [Policy Text Block]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_GoodwillAndIntangibleAssetsPolicyTextBlock" xlink:label="loc_us-gaap_GoodwillAndIntangibleAssetsPolicyTextBlock_AFE87DC89BBA0CE817C1EE536DD724DF" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_GoodwillAndIntangibleAssetsPolicyTextBlock_AFE87DC89BBA0CE817C1EE536DD724DF" xlink:to="lab_us-gaap_GoodwillAndIntangibleAssetsPolicyTextBlock_AFE87DC89BBA0CE817C1EE536DD724DF" xlink:type="arc" />
    <link:label id="lab_us-gaap_RevenueRecognitionPolicyTextBlock_9C3F3FCB144DEC7CBE9FEE536DD74C08_terseLabel_en-US" xlink:label="lab_us-gaap_RevenueRecognitionPolicyTextBlock_9C3F3FCB144DEC7CBE9FEE536DD74C08" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Revenue recognition</link:label>
    <link:label id="lab_us-gaap_RevenueRecognitionPolicyTextBlock_9C3F3FCB144DEC7CBE9FEE536DD74C08_label_en-US" xlink:label="lab_us-gaap_RevenueRecognitionPolicyTextBlock_9C3F3FCB144DEC7CBE9FEE536DD74C08" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Revenue Recognition, Policy [Policy Text Block]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RevenueRecognitionPolicyTextBlock" xlink:label="loc_us-gaap_RevenueRecognitionPolicyTextBlock_9C3F3FCB144DEC7CBE9FEE536DD74C08" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RevenueRecognitionPolicyTextBlock_9C3F3FCB144DEC7CBE9FEE536DD74C08" xlink:to="lab_us-gaap_RevenueRecognitionPolicyTextBlock_9C3F3FCB144DEC7CBE9FEE536DD74C08" xlink:type="arc" />
    <link:label id="lab_arnc_EnvironmentalMattersPolicyTextBlock_2DA22AB004DC69581693EE536DD72785_terseLabel_en-US" xlink:label="lab_arnc_EnvironmentalMattersPolicyTextBlock_2DA22AB004DC69581693EE536DD72785" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Environmental matters</link:label>
    <link:label id="lab_arnc_EnvironmentalMattersPolicyTextBlock_2DA22AB004DC69581693EE536DD72785_label_en-US" xlink:label="lab_arnc_EnvironmentalMattersPolicyTextBlock_2DA22AB004DC69581693EE536DD72785" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Environmental Matters Policy [Text Block]</link:label>
    <link:label id="lab_arnc_EnvironmentalMattersPolicyTextBlock_2DA22AB004DC69581693EE536DD72785_documentation_en-US" xlink:label="lab_arnc_EnvironmentalMattersPolicyTextBlock_2DA22AB004DC69581693EE536DD72785" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Environmental Matters Policy [Text Block]</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_EnvironmentalMattersPolicyTextBlock" xlink:label="loc_arnc_EnvironmentalMattersPolicyTextBlock_2DA22AB004DC69581693EE536DD72785" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_EnvironmentalMattersPolicyTextBlock_2DA22AB004DC69581693EE536DD72785" xlink:to="lab_arnc_EnvironmentalMattersPolicyTextBlock_2DA22AB004DC69581693EE536DD72785" xlink:type="arc" />
    <link:label id="lab_arnc_LitigationMattersPolicyTextBlock_768C4595FA95A53824E0EE536DD8E051_terseLabel_en-US" xlink:label="lab_arnc_LitigationMattersPolicyTextBlock_768C4595FA95A53824E0EE536DD8E051" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Litigation matters</link:label>
    <link:label id="lab_arnc_LitigationMattersPolicyTextBlock_768C4595FA95A53824E0EE536DD8E051_label_en-US" xlink:label="lab_arnc_LitigationMattersPolicyTextBlock_768C4595FA95A53824E0EE536DD8E051" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Litigation Matters Policy [Text Block]</link:label>
    <link:label id="lab_arnc_LitigationMattersPolicyTextBlock_768C4595FA95A53824E0EE536DD8E051_documentation_en-US" xlink:label="lab_arnc_LitigationMattersPolicyTextBlock_768C4595FA95A53824E0EE536DD8E051" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Litigation Matters Policy [Text Block]</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_LitigationMattersPolicyTextBlock" xlink:label="loc_arnc_LitigationMattersPolicyTextBlock_768C4595FA95A53824E0EE536DD8E051" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_LitigationMattersPolicyTextBlock_768C4595FA95A53824E0EE536DD8E051" xlink:to="lab_arnc_LitigationMattersPolicyTextBlock_768C4595FA95A53824E0EE536DD8E051" xlink:type="arc" />
    <link:label id="lab_us-gaap_IncomeTaxPolicyTextBlock_9FF38733F381FFD6F78FEE536DD8BEA0_terseLabel_en-US" xlink:label="lab_us-gaap_IncomeTaxPolicyTextBlock_9FF38733F381FFD6F78FEE536DD8BEA0" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Income taxes</link:label>
    <link:label id="lab_us-gaap_IncomeTaxPolicyTextBlock_9FF38733F381FFD6F78FEE536DD8BEA0_label_en-US" xlink:label="lab_us-gaap_IncomeTaxPolicyTextBlock_9FF38733F381FFD6F78FEE536DD8BEA0" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Income Tax, Policy [Policy Text Block]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_IncomeTaxPolicyTextBlock" xlink:label="loc_us-gaap_IncomeTaxPolicyTextBlock_9FF38733F381FFD6F78FEE536DD8BEA0" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncomeTaxPolicyTextBlock_9FF38733F381FFD6F78FEE536DD8BEA0" xlink:to="lab_us-gaap_IncomeTaxPolicyTextBlock_9FF38733F381FFD6F78FEE536DD8BEA0" xlink:type="arc" />
    <link:label id="lab_us-gaap_CompensationRelatedCostsPolicyTextBlock_1BE953A1C3F16F96BD66EE536DD8CB18_terseLabel_en-US" xlink:label="lab_us-gaap_CompensationRelatedCostsPolicyTextBlock_1BE953A1C3F16F96BD66EE536DD8CB18" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Stock-based compensation</link:label>
    <link:label id="lab_us-gaap_CompensationRelatedCostsPolicyTextBlock_1BE953A1C3F16F96BD66EE536DD8CB18_label_en-US" xlink:label="lab_us-gaap_CompensationRelatedCostsPolicyTextBlock_1BE953A1C3F16F96BD66EE536DD8CB18" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Compensation Related Costs, Policy [Policy Text Block]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_CompensationRelatedCostsPolicyTextBlock" xlink:label="loc_us-gaap_CompensationRelatedCostsPolicyTextBlock_1BE953A1C3F16F96BD66EE536DD8CB18" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CompensationRelatedCostsPolicyTextBlock_1BE953A1C3F16F96BD66EE536DD8CB18" xlink:to="lab_us-gaap_CompensationRelatedCostsPolicyTextBlock_1BE953A1C3F16F96BD66EE536DD8CB18" xlink:type="arc" />
    <link:label id="lab_us-gaap_ForeignCurrencyTransactionsAndTranslationsPolicyTextBlock_A54F28CAFD6A6552FBAFEE536DD89D76_terseLabel_en-US" xlink:label="lab_us-gaap_ForeignCurrencyTransactionsAndTranslationsPolicyTextBlock_A54F28CAFD6A6552FBAFEE536DD89D76" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Foreign currency</link:label>
    <link:label id="lab_us-gaap_ForeignCurrencyTransactionsAndTranslationsPolicyTextBlock_A54F28CAFD6A6552FBAFEE536DD89D76_label_en-US" xlink:label="lab_us-gaap_ForeignCurrencyTransactionsAndTranslationsPolicyTextBlock_A54F28CAFD6A6552FBAFEE536DD89D76" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Foreign Currency Transactions and Translations Policy [Policy Text Block]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ForeignCurrencyTransactionsAndTranslationsPolicyTextBlock" xlink:label="loc_us-gaap_ForeignCurrencyTransactionsAndTranslationsPolicyTextBlock_A54F28CAFD6A6552FBAFEE536DD89D76" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ForeignCurrencyTransactionsAndTranslationsPolicyTextBlock_A54F28CAFD6A6552FBAFEE536DD89D76" xlink:to="lab_us-gaap_ForeignCurrencyTransactionsAndTranslationsPolicyTextBlock_A54F28CAFD6A6552FBAFEE536DD89D76" xlink:type="arc" />
    <link:label id="lab_us-gaap_BusinessCombinationsAndOtherPurchaseOfBusinessTransactionsPolicyTextBlock_5845FC70D9A24255DBF6EE536DD80A0B_terseLabel_en-US" xlink:label="lab_us-gaap_BusinessCombinationsAndOtherPurchaseOfBusinessTransactionsPolicyTextBlock_5845FC70D9A24255DBF6EE536DD80A0B" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Acquisitions</link:label>
    <link:label id="lab_us-gaap_BusinessCombinationsAndOtherPurchaseOfBusinessTransactionsPolicyTextBlock_5845FC70D9A24255DBF6EE536DD80A0B_label_en-US" xlink:label="lab_us-gaap_BusinessCombinationsAndOtherPurchaseOfBusinessTransactionsPolicyTextBlock_5845FC70D9A24255DBF6EE536DD80A0B" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Business Combinations and Other Purchase of Business Transactions, Policy [Policy Text Block]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_BusinessCombinationsAndOtherPurchaseOfBusinessTransactionsPolicyTextBlock" xlink:label="loc_us-gaap_BusinessCombinationsAndOtherPurchaseOfBusinessTransactionsPolicyTextBlock_5845FC70D9A24255DBF6EE536DD80A0B" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_BusinessCombinationsAndOtherPurchaseOfBusinessTransactionsPolicyTextBlock_5845FC70D9A24255DBF6EE536DD80A0B" xlink:to="lab_us-gaap_BusinessCombinationsAndOtherPurchaseOfBusinessTransactionsPolicyTextBlock_5845FC70D9A24255DBF6EE536DD80A0B" xlink:type="arc" />
    <link:label id="lab_us-gaap_DiscontinuedOperationsPolicyTextBlock_3B07B37E26E8D5EFA19DEE536DD87E92_terseLabel_en-US" xlink:label="lab_us-gaap_DiscontinuedOperationsPolicyTextBlock_3B07B37E26E8D5EFA19DEE536DD87E92" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Discontinued operations and assets held for sale</link:label>
    <link:label id="lab_us-gaap_DiscontinuedOperationsPolicyTextBlock_3B07B37E26E8D5EFA19DEE536DD87E92_label_en-US" xlink:label="lab_us-gaap_DiscontinuedOperationsPolicyTextBlock_3B07B37E26E8D5EFA19DEE536DD87E92" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Discontinued Operations, Policy [Policy Text Block]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DiscontinuedOperationsPolicyTextBlock" xlink:label="loc_us-gaap_DiscontinuedOperationsPolicyTextBlock_3B07B37E26E8D5EFA19DEE536DD87E92" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DiscontinuedOperationsPolicyTextBlock_3B07B37E26E8D5EFA19DEE536DD87E92" xlink:to="lab_us-gaap_DiscontinuedOperationsPolicyTextBlock_3B07B37E26E8D5EFA19DEE536DD87E92" xlink:type="arc" />
    <link:label id="lab_us-gaap_NewAccountingPronouncementsPolicyPolicyTextBlock_CFF6F8BDE73676D2E519EE536DD955E5_terseLabel_en-US" xlink:label="lab_us-gaap_NewAccountingPronouncementsPolicyPolicyTextBlock_CFF6F8BDE73676D2E519EE536DD955E5" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Recently adopted and issued accounting guidance</link:label>
    <link:label id="lab_us-gaap_NewAccountingPronouncementsPolicyPolicyTextBlock_CFF6F8BDE73676D2E519EE536DD955E5_label_en-US" xlink:label="lab_us-gaap_NewAccountingPronouncementsPolicyPolicyTextBlock_CFF6F8BDE73676D2E519EE536DD955E5" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">New Accounting Pronouncements, Policy [Policy Text Block]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_NewAccountingPronouncementsPolicyPolicyTextBlock" xlink:label="loc_us-gaap_NewAccountingPronouncementsPolicyPolicyTextBlock_CFF6F8BDE73676D2E519EE536DD955E5" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_NewAccountingPronouncementsPolicyPolicyTextBlock_CFF6F8BDE73676D2E519EE536DD955E5" xlink:to="lab_us-gaap_NewAccountingPronouncementsPolicyPolicyTextBlock_CFF6F8BDE73676D2E519EE536DD955E5" xlink:type="arc" />
    <link:label id="lab_us-gaap_SignificantAccountingPoliciesTextBlock_6415AB22FCA58296AF847C36307D6DC6_terseLabel_en-US" xlink:label="lab_us-gaap_SignificantAccountingPoliciesTextBlock_6415AB22FCA58296AF847C36307D6DC6" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Summary of Significant Accounting Policies</link:label>
    <link:label id="lab_us-gaap_SignificantAccountingPoliciesTextBlock_6415AB22FCA58296AF847C36307D6DC6_label_en-US" xlink:label="lab_us-gaap_SignificantAccountingPoliciesTextBlock_6415AB22FCA58296AF847C36307D6DC6" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Significant Accounting Policies [Text Block]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_SignificantAccountingPoliciesTextBlock" xlink:label="loc_us-gaap_SignificantAccountingPoliciesTextBlock_6415AB22FCA58296AF847C36307D6DC6" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SignificantAccountingPoliciesTextBlock_6415AB22FCA58296AF847C36307D6DC6" xlink:to="lab_us-gaap_SignificantAccountingPoliciesTextBlock_6415AB22FCA58296AF847C36307D6DC6" xlink:type="arc" />
    <link:label id="lab_arnc_PensionSettlementCostMember_1F21B953A4821926B327DEFAB9FC6FDC_terseLabel_en-US" xlink:label="lab_arnc_PensionSettlementCostMember_1F21B953A4821926B327DEFAB9FC6FDC" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Pension Settlement Cost</link:label>
    <link:label id="lab_arnc_PensionSettlementCostMember_1F21B953A4821926B327DEFAB9FC6FDC_label_en-US" xlink:label="lab_arnc_PensionSettlementCostMember_1F21B953A4821926B327DEFAB9FC6FDC" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Pension Settlement Cost [Member]</link:label>
    <link:label id="lab_arnc_PensionSettlementCostMember_1F21B953A4821926B327DEFAB9FC6FDC_documentation_en-US" xlink:label="lab_arnc_PensionSettlementCostMember_1F21B953A4821926B327DEFAB9FC6FDC" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Pension settlement cost.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_PensionSettlementCostMember" xlink:label="loc_arnc_PensionSettlementCostMember_1F21B953A4821926B327DEFAB9FC6FDC" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_PensionSettlementCostMember_1F21B953A4821926B327DEFAB9FC6FDC" xlink:to="lab_arnc_PensionSettlementCostMember_1F21B953A4821926B327DEFAB9FC6FDC" xlink:type="arc" />
    <link:label id="lab_us-gaap_IncreaseDecreaseInPensionPlanObligations_D8E76EE282EDCE17F9B7DEFAB9FF3D23_negatedLabel_en-US" xlink:label="lab_us-gaap_IncreaseDecreaseInPensionPlanObligations_D8E76EE282EDCE17F9B7DEFAB9FF3D23" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xml:lang="en-US">Decrease in pension liability, plan amendment</link:label>
    <link:label id="lab_us-gaap_IncreaseDecreaseInPensionPlanObligations_D8E76EE282EDCE17F9B7DEFAB9FF3D23_label_en-US" xlink:label="lab_us-gaap_IncreaseDecreaseInPensionPlanObligations_D8E76EE282EDCE17F9B7DEFAB9FF3D23" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Increase (Decrease) in Obligation, Pension Benefits</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_IncreaseDecreaseInPensionPlanObligations" xlink:label="loc_us-gaap_IncreaseDecreaseInPensionPlanObligations_D8E76EE282EDCE17F9B7DEFAB9FF3D23" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncreaseDecreaseInPensionPlanObligations_D8E76EE282EDCE17F9B7DEFAB9FF3D23" xlink:to="lab_us-gaap_IncreaseDecreaseInPensionPlanObligations_D8E76EE282EDCE17F9B7DEFAB9FF3D23" xlink:type="arc" />
    <link:label id="lab_us-gaap_DefinedBenefitPlanRecognizedNetGainLossDueToCurtailments_DBFC8D2CEBB4D3CA38B7DEFAB9FF25FB_negatedTerseLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanRecognizedNetGainLossDueToCurtailments_DBFC8D2CEBB4D3CA38B7DEFAB9FF25FB" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:type="resource" xml:lang="en-US">Curtailments</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DefinedBenefitPlanRecognizedNetGainLossDueToCurtailments" xlink:label="loc_us-gaap_DefinedBenefitPlanRecognizedNetGainLossDueToCurtailments_DBFC8D2CEBB4D3CA38B7DEFAB9FF25FB" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanRecognizedNetGainLossDueToCurtailments_DBFC8D2CEBB4D3CA38B7DEFAB9FF25FB" xlink:to="lab_us-gaap_DefinedBenefitPlanRecognizedNetGainLossDueToCurtailments_DBFC8D2CEBB4D3CA38B7DEFAB9FF25FB" xlink:type="arc" />
    <link:label id="lab_us-gaap_OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax_5DB8D063C5ECDC5288F3DEFAB9FF52F4_negatedLabel_en-US" xlink:label="lab_us-gaap_OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax_5DB8D063C5ECDC5288F3DEFAB9FF52F4" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xml:lang="en-US">Offset to AOCI, net of tax</link:label>
    <link:label id="lab_us-gaap_OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax_5DB8D063C5ECDC5288F3DEFAB9FF52F4_label_en-US" xlink:label="lab_us-gaap_OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax_5DB8D063C5ECDC5288F3DEFAB9FF52F4" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, after Tax</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax_5DB8D063C5ECDC5288F3DEFAB9FF52F4" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax_5DB8D063C5ECDC5288F3DEFAB9FF52F4" xlink:to="lab_us-gaap_OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax_5DB8D063C5ECDC5288F3DEFAB9FF52F4" xlink:type="arc" />
    <link:label id="lab_arnc_LaborAgreementDuration_00AD8A8029E74B4D8C50DEFABA0006C5_terseLabel_en-US" xlink:label="lab_arnc_LaborAgreementDuration_00AD8A8029E74B4D8C50DEFABA0006C5" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Duration of labor agreement</link:label>
    <link:label id="lab_arnc_LaborAgreementDuration_00AD8A8029E74B4D8C50DEFABA0006C5_label_en-US" xlink:label="lab_arnc_LaborAgreementDuration_00AD8A8029E74B4D8C50DEFABA0006C5" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Labor Agreement, Duration</link:label>
    <link:label id="lab_arnc_LaborAgreementDuration_00AD8A8029E74B4D8C50DEFABA0006C5_documentation_en-US" xlink:label="lab_arnc_LaborAgreementDuration_00AD8A8029E74B4D8C50DEFABA0006C5" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Labor Agreement, Duration</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_LaborAgreementDuration" xlink:label="loc_arnc_LaborAgreementDuration_00AD8A8029E74B4D8C50DEFABA0006C5" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_LaborAgreementDuration_00AD8A8029E74B4D8C50DEFABA0006C5" xlink:to="lab_arnc_LaborAgreementDuration_00AD8A8029E74B4D8C50DEFABA0006C5" xlink:type="arc" />
    <link:label id="lab_arnc_LaborAgreementNumberOfEmployees_41980D1F73CB04756B51DEFABA003536_terseLabel_en-US" xlink:label="lab_arnc_LaborAgreementNumberOfEmployees_41980D1F73CB04756B51DEFABA003536" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Number of employees included in Labor Agreement</link:label>
    <link:label id="lab_arnc_LaborAgreementNumberOfEmployees_41980D1F73CB04756B51DEFABA003536_label_en-US" xlink:label="lab_arnc_LaborAgreementNumberOfEmployees_41980D1F73CB04756B51DEFABA003536" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Labor Agreement, Number Of Employees</link:label>
    <link:label id="lab_arnc_LaborAgreementNumberOfEmployees_41980D1F73CB04756B51DEFABA003536_documentation_en-US" xlink:label="lab_arnc_LaborAgreementNumberOfEmployees_41980D1F73CB04756B51DEFABA003536" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Labor Agreement, Number Of Employees</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_LaborAgreementNumberOfEmployees" xlink:label="loc_arnc_LaborAgreementNumberOfEmployees_41980D1F73CB04756B51DEFABA003536" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_LaborAgreementNumberOfEmployees_41980D1F73CB04756B51DEFABA003536" xlink:to="lab_arnc_LaborAgreementNumberOfEmployees_41980D1F73CB04756B51DEFABA003536" xlink:type="arc" />
    <link:label id="lab_arnc_DefinedBenefitPlanLaborAgreementEmployeesSubjectToRetirementBenefitIncrease_C7B27B5B8AE0A046F65CDEFABA00AA9A_terseLabel_en-US" xlink:label="lab_arnc_DefinedBenefitPlanLaborAgreementEmployeesSubjectToRetirementBenefitIncrease_C7B27B5B8AE0A046F65CDEFABA00AA9A" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Employees subject to retirement benefit increase under Labor Agreement</link:label>
    <link:label id="lab_arnc_DefinedBenefitPlanLaborAgreementEmployeesSubjectToRetirementBenefitIncrease_C7B27B5B8AE0A046F65CDEFABA00AA9A_label_en-US" xlink:label="lab_arnc_DefinedBenefitPlanLaborAgreementEmployeesSubjectToRetirementBenefitIncrease_C7B27B5B8AE0A046F65CDEFABA00AA9A" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Labor Agreement, Employees Subject To Retirement Benefit Increase</link:label>
    <link:label id="lab_arnc_DefinedBenefitPlanLaborAgreementEmployeesSubjectToRetirementBenefitIncrease_C7B27B5B8AE0A046F65CDEFABA00AA9A_documentation_en-US" xlink:label="lab_arnc_DefinedBenefitPlanLaborAgreementEmployeesSubjectToRetirementBenefitIncrease_C7B27B5B8AE0A046F65CDEFABA00AA9A" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Labor Agreement, Employees Subject To Retirement Benefit Increase</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_DefinedBenefitPlanLaborAgreementEmployeesSubjectToRetirementBenefitIncrease" xlink:label="loc_arnc_DefinedBenefitPlanLaborAgreementEmployeesSubjectToRetirementBenefitIncrease_C7B27B5B8AE0A046F65CDEFABA00AA9A" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_DefinedBenefitPlanLaborAgreementEmployeesSubjectToRetirementBenefitIncrease_C7B27B5B8AE0A046F65CDEFABA00AA9A" xlink:to="lab_arnc_DefinedBenefitPlanLaborAgreementEmployeesSubjectToRetirementBenefitIncrease_C7B27B5B8AE0A046F65CDEFABA00AA9A" xlink:type="arc" />
    <link:label id="lab_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_EEE56CD8A5EA2399B24EE248CE34D4B0_terseLabel_en-US" xlink:label="lab_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_EEE56CD8A5EA2399B24EE248CE34D4B0" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Schedule of Segment Reporting Information, by Segment [Table]</link:label>
    <link:label id="lab_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_EEE56CD8A5EA2399B24EE248CE34D4B0_label_en-US" xlink:label="lab_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_EEE56CD8A5EA2399B24EE248CE34D4B0" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Schedule of Segment Reporting Information, by Segment [Table]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable" xlink:label="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_EEE56CD8A5EA2399B24EE248CE34D4B0" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_EEE56CD8A5EA2399B24EE248CE34D4B0" xlink:to="lab_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_EEE56CD8A5EA2399B24EE248CE34D4B0" xlink:type="arc" />
    <link:label id="lab_arnc_GlobalRolledProductsMember_232649F78E12209AEEAEE248CE34B671_terseLabel_en-US" xlink:label="lab_arnc_GlobalRolledProductsMember_232649F78E12209AEEAEE248CE34B671" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Global Rolled Products</link:label>
    <link:label id="lab_arnc_GlobalRolledProductsMember_232649F78E12209AEEAEE248CE34B671_label_en-US" xlink:label="lab_arnc_GlobalRolledProductsMember_232649F78E12209AEEAEE248CE34B671" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Global Rolled Products [Member]</link:label>
    <link:label id="lab_arnc_GlobalRolledProductsMember_232649F78E12209AEEAEE248CE34B671_documentation_en-US" xlink:label="lab_arnc_GlobalRolledProductsMember_232649F78E12209AEEAEE248CE34B671" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Global rolled products.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_GlobalRolledProductsMember" xlink:label="loc_arnc_GlobalRolledProductsMember_232649F78E12209AEEAEE248CE34B671" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_GlobalRolledProductsMember_232649F78E12209AEEAEE248CE34B671" xlink:to="lab_arnc_GlobalRolledProductsMember_232649F78E12209AEEAEE248CE34B671" xlink:type="arc" />
    <link:label id="lab_us-gaap_IntersegmentEliminationMember_52A15C5F879EF6BE7B88E248CE380976_terseLabel_en-US" xlink:label="lab_us-gaap_IntersegmentEliminationMember_52A15C5F879EF6BE7B88E248CE380976" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Intersegment Eliminations</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_IntersegmentEliminationMember" xlink:label="loc_us-gaap_IntersegmentEliminationMember_52A15C5F879EF6BE7B88E248CE380976" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IntersegmentEliminationMember_52A15C5F879EF6BE7B88E248CE380976" xlink:to="lab_us-gaap_IntersegmentEliminationMember_52A15C5F879EF6BE7B88E248CE380976" xlink:type="arc" />
    <link:label id="lab_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_72040F272A481BA80632E248CE3839C3_terseLabel_en-US" xlink:label="lab_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_72040F272A481BA80632E248CE3839C3" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Related Party [Axis]</link:label>
    <link:label id="lab_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_72040F272A481BA80632E248CE3839C3_label_en-US" xlink:label="lab_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_72040F272A481BA80632E248CE3839C3" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Related Party [Axis]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RelatedPartyTransactionsByRelatedPartyAxis" xlink:label="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_72040F272A481BA80632E248CE3839C3" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_72040F272A481BA80632E248CE3839C3" xlink:to="lab_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_72040F272A481BA80632E248CE3839C3" xlink:type="arc" />
    <link:label id="lab_us-gaap_RelatedPartyDomain_E00066D57EBD37E78690E248CE38B78A_terseLabel_en-US" xlink:label="lab_us-gaap_RelatedPartyDomain_E00066D57EBD37E78690E248CE38B78A" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Related Party [Domain]</link:label>
    <link:label id="lab_us-gaap_RelatedPartyDomain_E00066D57EBD37E78690E248CE38B78A_label_en-US" xlink:label="lab_us-gaap_RelatedPartyDomain_E00066D57EBD37E78690E248CE38B78A" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Related Party [Domain]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RelatedPartyDomain" xlink:label="loc_us-gaap_RelatedPartyDomain_E00066D57EBD37E78690E248CE38B78A" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RelatedPartyDomain_E00066D57EBD37E78690E248CE38B78A" xlink:to="lab_us-gaap_RelatedPartyDomain_E00066D57EBD37E78690E248CE38B78A" xlink:type="arc" />
    <link:label id="lab_us-gaap_SegmentReportingInformationLineItems_AD5336A251C461CF2436E248CE38D3A0_terseLabel_en-US" xlink:label="lab_us-gaap_SegmentReportingInformationLineItems_AD5336A251C461CF2436E248CE38D3A0" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Segment Reporting Information [Line Items]</link:label>
    <link:label id="lab_us-gaap_SegmentReportingInformationLineItems_AD5336A251C461CF2436E248CE38D3A0_label_en-US" xlink:label="lab_us-gaap_SegmentReportingInformationLineItems_AD5336A251C461CF2436E248CE38D3A0" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Segment Reporting Information [Line Items]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_SegmentReportingInformationLineItems" xlink:label="loc_us-gaap_SegmentReportingInformationLineItems_AD5336A251C461CF2436E248CE38D3A0" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_AD5336A251C461CF2436E248CE38D3A0" xlink:to="lab_us-gaap_SegmentReportingInformationLineItems_AD5336A251C461CF2436E248CE38D3A0" xlink:type="arc" />
    <link:label id="lab_us-gaap_GrossProfit_6FDD768ACA080389C584E248CE3856C7_verboseLabel_en-US" xlink:label="lab_us-gaap_GrossProfit_6FDD768ACA080389C584E248CE3856C7" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Segment operating profit</link:label>
    <link:label id="lab_us-gaap_GrossProfit_6FDD768ACA080389C584E248CE3856C7_label_en-US" xlink:label="lab_us-gaap_GrossProfit_6FDD768ACA080389C584E248CE3856C7" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Gross Profit</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_GrossProfit" xlink:label="loc_us-gaap_GrossProfit_6FDD768ACA080389C584E248CE3856C7" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_GrossProfit_6FDD768ACA080389C584E248CE3856C7" xlink:to="lab_us-gaap_GrossProfit_6FDD768ACA080389C584E248CE3856C7" xlink:type="arc" />
    <link:label id="lab_us-gaap_DepreciationDepletionAndAmortization_DE47856949EF44C4B684E248CE38C832_verboseLabel_en-US" xlink:label="lab_us-gaap_DepreciationDepletionAndAmortization_DE47856949EF44C4B684E248CE38C832" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Provision for depreciation and amortization</link:label>
    <link:label id="lab_us-gaap_DepreciationDepletionAndAmortization_DE47856949EF44C4B684E248CE38C832_label_en-US" xlink:label="lab_us-gaap_DepreciationDepletionAndAmortization_DE47856949EF44C4B684E248CE38C832" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Depreciation, Depletion and Amortization</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DepreciationDepletionAndAmortization" xlink:label="loc_us-gaap_DepreciationDepletionAndAmortization_DE47856949EF44C4B684E248CE38C832" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DepreciationDepletionAndAmortization_DE47856949EF44C4B684E248CE38C832" xlink:to="lab_us-gaap_DepreciationDepletionAndAmortization_DE47856949EF44C4B684E248CE38C832" xlink:type="arc" />
    <link:label id="lab_arnc_SegmentReportingInformationCapitalExpenditures_AD92C6EC5058CA4DA9C5E248CE386B56_terseLabel_en-US" xlink:label="lab_arnc_SegmentReportingInformationCapitalExpenditures_AD92C6EC5058CA4DA9C5E248CE386B56" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Capital expenditures</link:label>
    <link:label id="lab_arnc_SegmentReportingInformationCapitalExpenditures_AD92C6EC5058CA4DA9C5E248CE386B56_label_en-US" xlink:label="lab_arnc_SegmentReportingInformationCapitalExpenditures_AD92C6EC5058CA4DA9C5E248CE386B56" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Segment Reporting Information Capital Expenditures</link:label>
    <link:label id="lab_arnc_SegmentReportingInformationCapitalExpenditures_AD92C6EC5058CA4DA9C5E248CE386B56_documentation_en-US" xlink:label="lab_arnc_SegmentReportingInformationCapitalExpenditures_AD92C6EC5058CA4DA9C5E248CE386B56" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Segment Reporting Information Capital Expenditures</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_SegmentReportingInformationCapitalExpenditures" xlink:label="loc_arnc_SegmentReportingInformationCapitalExpenditures_AD92C6EC5058CA4DA9C5E248CE386B56" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_SegmentReportingInformationCapitalExpenditures_AD92C6EC5058CA4DA9C5E248CE386B56" xlink:to="lab_arnc_SegmentReportingInformationCapitalExpenditures_AD92C6EC5058CA4DA9C5E248CE386B56" xlink:type="arc" />
    <link:label id="lab_us-gaap_Goodwill_96F0869297AAF3502B7DE248CE38CB59_terseLabel_en-US" xlink:label="lab_us-gaap_Goodwill_96F0869297AAF3502B7DE248CE38CB59" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Goodwill</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_Goodwill" xlink:label="loc_us-gaap_Goodwill_96F0869297AAF3502B7DE248CE38CB59" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_Goodwill_96F0869297AAF3502B7DE248CE38CB59" xlink:to="lab_us-gaap_Goodwill_96F0869297AAF3502B7DE248CE38CB59" xlink:type="arc" />
    <link:label id="lab_us-gaap_Assets_E32330CFEF12ADA903BBE248CE38C177_terseLabel_en-US" xlink:label="lab_us-gaap_Assets_E32330CFEF12ADA903BBE248CE38C177" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Assets</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_Assets" xlink:label="loc_us-gaap_Assets_E32330CFEF12ADA903BBE248CE38C177" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_Assets_E32330CFEF12ADA903BBE248CE38C177" xlink:to="lab_us-gaap_Assets_E32330CFEF12ADA903BBE248CE38C177" xlink:type="arc" />
    <link:label id="lab_us-gaap_DisposalGroupsIncludingDiscontinuedOperationsDisclosureTextBlock_3E069D232C6529EB2DD3E244A8BA6950_terseLabel_en-US" xlink:label="lab_us-gaap_DisposalGroupsIncludingDiscontinuedOperationsDisclosureTextBlock_3E069D232C6529EB2DD3E244A8BA6950" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Separation Transaction and Discontinued Operations</link:label>
    <link:label id="lab_us-gaap_DisposalGroupsIncludingDiscontinuedOperationsDisclosureTextBlock_3E069D232C6529EB2DD3E244A8BA6950_label_en-US" xlink:label="lab_us-gaap_DisposalGroupsIncludingDiscontinuedOperationsDisclosureTextBlock_3E069D232C6529EB2DD3E244A8BA6950" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Disposal Groups, Including Discontinued Operations, Disclosure [Text Block]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DisposalGroupsIncludingDiscontinuedOperationsDisclosureTextBlock" xlink:label="loc_us-gaap_DisposalGroupsIncludingDiscontinuedOperationsDisclosureTextBlock_3E069D232C6529EB2DD3E244A8BA6950" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DisposalGroupsIncludingDiscontinuedOperationsDisclosureTextBlock_3E069D232C6529EB2DD3E244A8BA6950" xlink:to="lab_us-gaap_DisposalGroupsIncludingDiscontinuedOperationsDisclosureTextBlock_3E069D232C6529EB2DD3E244A8BA6950" xlink:type="arc" />
    <link:label id="lab_arnc_FirthRixsonMember_69225A783C0CDC3C8EFA0735D9F2C832_terseLabel_en-US" xlink:label="lab_arnc_FirthRixsonMember_69225A783C0CDC3C8EFA0735D9F2C832" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Firth Rixson</link:label>
    <link:label id="lab_arnc_FirthRixsonMember_69225A783C0CDC3C8EFA0735D9F2C832_label_en-US" xlink:label="lab_arnc_FirthRixsonMember_69225A783C0CDC3C8EFA0735D9F2C832" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Firth Rixson [Member]</link:label>
    <link:label id="lab_arnc_FirthRixsonMember_69225A783C0CDC3C8EFA0735D9F2C832_documentation_en-US" xlink:label="lab_arnc_FirthRixsonMember_69225A783C0CDC3C8EFA0735D9F2C832" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Firth Rixson [Member]</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_FirthRixsonMember" xlink:label="loc_arnc_FirthRixsonMember_69225A783C0CDC3C8EFA0735D9F2C832" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_FirthRixsonMember_69225A783C0CDC3C8EFA0735D9F2C832" xlink:to="lab_arnc_FirthRixsonMember_69225A783C0CDC3C8EFA0735D9F2C832" xlink:type="arc" />
    <link:label id="lab_srt_RangeAxis_FC469609820D43EF656B0735D9F286DD_terseLabel_en-US" xlink:label="lab_srt_RangeAxis_FC469609820D43EF656B0735D9F286DD" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Range [Axis]</link:label>
    <link:label id="lab_srt_RangeAxis_FC469609820D43EF656B0735D9F286DD_label_en-US" xlink:label="lab_srt_RangeAxis_FC469609820D43EF656B0735D9F286DD" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Range [Axis]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_RangeAxis" xlink:label="loc_srt_RangeAxis_FC469609820D43EF656B0735D9F286DD" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_srt_RangeAxis_FC469609820D43EF656B0735D9F286DD" xlink:to="lab_srt_RangeAxis_FC469609820D43EF656B0735D9F286DD" xlink:type="arc" />
    <link:label id="lab_srt_RangeMember_ED1D0A132136CA6F11C60735D9F2CCB2_terseLabel_en-US" xlink:label="lab_srt_RangeMember_ED1D0A132136CA6F11C60735D9F2CCB2" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Range [Domain]</link:label>
    <link:label id="lab_srt_RangeMember_ED1D0A132136CA6F11C60735D9F2CCB2_label_en-US" xlink:label="lab_srt_RangeMember_ED1D0A132136CA6F11C60735D9F2CCB2" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Range [Domain]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_RangeMember" xlink:label="loc_srt_RangeMember_ED1D0A132136CA6F11C60735D9F2CCB2" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_srt_RangeMember_ED1D0A132136CA6F11C60735D9F2CCB2" xlink:to="lab_srt_RangeMember_ED1D0A132136CA6F11C60735D9F2CCB2" xlink:type="arc" />
    <link:label id="lab_srt_MaximumMember_D37DD34A1969F8FCD0130735D9F2F1D4_terseLabel_en-US" xlink:label="lab_srt_MaximumMember_D37DD34A1969F8FCD0130735D9F2F1D4" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Maximum</link:label>
    <link:label id="lab_srt_MaximumMember_D37DD34A1969F8FCD0130735D9F2F1D4_label_en-US" xlink:label="lab_srt_MaximumMember_D37DD34A1969F8FCD0130735D9F2F1D4" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Maximum [Member]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_MaximumMember" xlink:label="loc_srt_MaximumMember_D37DD34A1969F8FCD0130735D9F2F1D4" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_srt_MaximumMember_D37DD34A1969F8FCD0130735D9F2F1D4" xlink:to="lab_srt_MaximumMember_D37DD34A1969F8FCD0130735D9F2F1D4" xlink:type="arc" />
    <link:label id="lab_us-gaap_BusinessCombinationContingentConsiderationLiability_0EEDF9A842ECD8C1E1460735D9F21F20_verboseLabel_en-US" xlink:label="lab_us-gaap_BusinessCombinationContingentConsiderationLiability_0EEDF9A842ECD8C1E1460735D9F21F20" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Contingent consideration liability</link:label>
    <link:label id="lab_us-gaap_BusinessCombinationContingentConsiderationLiability_0EEDF9A842ECD8C1E1460735D9F21F20_label_en-US" xlink:label="lab_us-gaap_BusinessCombinationContingentConsiderationLiability_0EEDF9A842ECD8C1E1460735D9F21F20" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Business Combination, Contingent Consideration, Liability</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_BusinessCombinationContingentConsiderationLiability" xlink:label="loc_us-gaap_BusinessCombinationContingentConsiderationLiability_0EEDF9A842ECD8C1E1460735D9F21F20" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_BusinessCombinationContingentConsiderationLiability_0EEDF9A842ECD8C1E1460735D9F21F20" xlink:to="lab_us-gaap_BusinessCombinationContingentConsiderationLiability_0EEDF9A842ECD8C1E1460735D9F21F20" xlink:type="arc" />
    <link:label id="lab_us-gaap_BusinessCombinationContingentConsiderationArrangementsChangeInAmountOfContingentConsiderationLiability1_D5BFE6D1CBAC597430630735D9F28EED_terseLabel_en-US" xlink:label="lab_us-gaap_BusinessCombinationContingentConsiderationArrangementsChangeInAmountOfContingentConsiderationLiability1_D5BFE6D1CBAC597430630735D9F28EED" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Contingent consideration arrangements, change in amount of contingent consideration, liability</link:label>
    <link:label id="lab_us-gaap_BusinessCombinationContingentConsiderationArrangementsChangeInAmountOfContingentConsiderationLiability1_D5BFE6D1CBAC597430630735D9F28EED_label_en-US" xlink:label="lab_us-gaap_BusinessCombinationContingentConsiderationArrangementsChangeInAmountOfContingentConsiderationLiability1_D5BFE6D1CBAC597430630735D9F28EED" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Business Combination, Contingent Consideration Arrangements, Change in Amount of Contingent Consideration, Liability</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_BusinessCombinationContingentConsiderationArrangementsChangeInAmountOfContingentConsiderationLiability1" xlink:label="loc_us-gaap_BusinessCombinationContingentConsiderationArrangementsChangeInAmountOfContingentConsiderationLiability1_D5BFE6D1CBAC597430630735D9F28EED" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_BusinessCombinationContingentConsiderationArrangementsChangeInAmountOfContingentConsiderationLiability1_D5BFE6D1CBAC597430630735D9F28EED" xlink:to="lab_us-gaap_BusinessCombinationContingentConsiderationArrangementsChangeInAmountOfContingentConsiderationLiability1_D5BFE6D1CBAC597430630735D9F28EED" xlink:type="arc" />
    <link:label id="lab_us-gaap_QuarterlyFinancialInformationDisclosureAbstract_67F70B77716405BC27E6E244A876F937_label_en-US" xlink:label="lab_us-gaap_QuarterlyFinancialInformationDisclosureAbstract_67F70B77716405BC27E6E244A876F937" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Quarterly Financial Information Disclosure [Abstract]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_QuarterlyFinancialInformationDisclosureAbstract" xlink:label="loc_us-gaap_QuarterlyFinancialInformationDisclosureAbstract_67F70B77716405BC27E6E244A876F937" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_QuarterlyFinancialInformationDisclosureAbstract_67F70B77716405BC27E6E244A876F937" xlink:to="lab_us-gaap_QuarterlyFinancialInformationDisclosureAbstract_67F70B77716405BC27E6E244A876F937" xlink:type="arc" />
    <link:label id="lab_arnc_TexarkanaTexasRollingMillMember_14551DF5E1E8F14B2695E244A87ED890_terseLabel_en-US" xlink:label="lab_arnc_TexarkanaTexasRollingMillMember_14551DF5E1E8F14B2695E244A87ED890" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Texarkana, Texas Rolling Mill</link:label>
    <link:label id="lab_arnc_TexarkanaTexasRollingMillMember_14551DF5E1E8F14B2695E244A87ED890_label_en-US" xlink:label="lab_arnc_TexarkanaTexasRollingMillMember_14551DF5E1E8F14B2695E244A87ED890" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Texarkana, Texas Rolling Mill [Member]</link:label>
    <link:label id="lab_arnc_TexarkanaTexasRollingMillMember_14551DF5E1E8F14B2695E244A87ED890_documentation_en-US" xlink:label="lab_arnc_TexarkanaTexasRollingMillMember_14551DF5E1E8F14B2695E244A87ED890" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Texarkana, Texas Rolling Mill [Member]</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_TexarkanaTexasRollingMillMember" xlink:label="loc_arnc_TexarkanaTexasRollingMillMember_14551DF5E1E8F14B2695E244A87ED890" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_TexarkanaTexasRollingMillMember_14551DF5E1E8F14B2695E244A87ED890" xlink:to="lab_arnc_TexarkanaTexasRollingMillMember_14551DF5E1E8F14B2695E244A87ED890" xlink:type="arc" />
    <link:label id="lab_us-gaap_NetIncomeLoss_22C7BCFF669B6ACDF368E244A8825B00_terseLabel_en-US" xlink:label="lab_us-gaap_NetIncomeLoss_22C7BCFF669B6ACDF368E244A8825B00" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Net income</link:label>
    <link:label id="lab_us-gaap_NetIncomeLoss_22C7BCFF669B6ACDF368E244A8825B00_label_en-US" xlink:label="lab_us-gaap_NetIncomeLoss_22C7BCFF669B6ACDF368E244A8825B00" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Net Income (Loss) Attributable to Parent</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_NetIncomeLoss" xlink:label="loc_us-gaap_NetIncomeLoss_22C7BCFF669B6ACDF368E244A8825B00" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_NetIncomeLoss_22C7BCFF669B6ACDF368E244A8825B00" xlink:to="lab_us-gaap_NetIncomeLoss_22C7BCFF669B6ACDF368E244A8825B00" xlink:type="arc" />
    <link:label id="lab_us-gaap_EarningsPerShareBasicAbstract_9A6CAA9CC14A4ED64C29E244A886749B_terseLabel_en-US" xlink:label="lab_us-gaap_EarningsPerShareBasicAbstract_9A6CAA9CC14A4ED64C29E244A886749B" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Basic</link:label>
    <link:label id="lab_us-gaap_EarningsPerShareBasicAbstract_9A6CAA9CC14A4ED64C29E244A886749B_label_en-US" xlink:label="lab_us-gaap_EarningsPerShareBasicAbstract_9A6CAA9CC14A4ED64C29E244A886749B" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Earnings Per Share, Basic [Abstract]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_EarningsPerShareBasicAbstract" xlink:label="loc_us-gaap_EarningsPerShareBasicAbstract_9A6CAA9CC14A4ED64C29E244A886749B" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_EarningsPerShareBasicAbstract_9A6CAA9CC14A4ED64C29E244A886749B" xlink:to="lab_us-gaap_EarningsPerShareBasicAbstract_9A6CAA9CC14A4ED64C29E244A886749B" xlink:type="arc" />
    <link:label id="lab_us-gaap_EarningsPerShareBasic_6809F8B0AF662C217A2BE244A8869376_totalLabel_en-US" xlink:label="lab_us-gaap_EarningsPerShareBasic_6809F8B0AF662C217A2BE244A8869376" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Net loss per share-basic (in usd per share)</link:label>
    <link:label id="lab_us-gaap_EarningsPerShareBasic_6809F8B0AF662C217A2BE244A8869376_label_en-US" xlink:label="lab_us-gaap_EarningsPerShareBasic_6809F8B0AF662C217A2BE244A8869376" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Earnings Per Share, Basic</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_EarningsPerShareBasic" xlink:label="loc_us-gaap_EarningsPerShareBasic_6809F8B0AF662C217A2BE244A8869376" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_EarningsPerShareBasic_6809F8B0AF662C217A2BE244A8869376" xlink:to="lab_us-gaap_EarningsPerShareBasic_6809F8B0AF662C217A2BE244A8869376" xlink:type="arc" />
    <link:label id="lab_us-gaap_EarningsPerShareDilutedAbstract_584D39B7F70C59101840E244A886A5DF_terseLabel_en-US" xlink:label="lab_us-gaap_EarningsPerShareDilutedAbstract_584D39B7F70C59101840E244A886A5DF" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Diluted</link:label>
    <link:label id="lab_us-gaap_EarningsPerShareDilutedAbstract_584D39B7F70C59101840E244A886A5DF_label_en-US" xlink:label="lab_us-gaap_EarningsPerShareDilutedAbstract_584D39B7F70C59101840E244A886A5DF" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Earnings Per Share, Diluted [Abstract]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_EarningsPerShareDilutedAbstract" xlink:label="loc_us-gaap_EarningsPerShareDilutedAbstract_584D39B7F70C59101840E244A886A5DF" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_EarningsPerShareDilutedAbstract_584D39B7F70C59101840E244A886A5DF" xlink:to="lab_us-gaap_EarningsPerShareDilutedAbstract_584D39B7F70C59101840E244A886A5DF" xlink:type="arc" />
    <link:label id="lab_us-gaap_EarningsPerShareDiluted_45EC23350A4409C9D289E244A8862F0C_totalLabel_en-US" xlink:label="lab_us-gaap_EarningsPerShareDiluted_45EC23350A4409C9D289E244A8862F0C" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Net loss per share-diluted (in usd per share)</link:label>
    <link:label id="lab_us-gaap_EarningsPerShareDiluted_45EC23350A4409C9D289E244A8862F0C_label_en-US" xlink:label="lab_us-gaap_EarningsPerShareDiluted_45EC23350A4409C9D289E244A8862F0C" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Earnings Per Share, Diluted</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_EarningsPerShareDiluted" xlink:label="loc_us-gaap_EarningsPerShareDiluted_45EC23350A4409C9D289E244A8862F0C" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_EarningsPerShareDiluted_45EC23350A4409C9D289E244A8862F0C" xlink:to="lab_us-gaap_EarningsPerShareDiluted_45EC23350A4409C9D289E244A8862F0C" xlink:type="arc" />
    <link:label id="lab_arnc_GainLossOnDispositionOfAssetsNetOfTax_1B3316BD473FD618846AE244A88684EA_terseLabel_en-US" xlink:label="lab_arnc_GainLossOnDispositionOfAssetsNetOfTax_1B3316BD473FD618846AE244A88684EA" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Gain on disposition of assets, after tax</link:label>
    <link:label id="lab_arnc_GainLossOnDispositionOfAssetsNetOfTax_1B3316BD473FD618846AE244A88684EA_label_en-US" xlink:label="lab_arnc_GainLossOnDispositionOfAssetsNetOfTax_1B3316BD473FD618846AE244A88684EA" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Gain (Loss) On Disposition of Assets Net of Tax</link:label>
    <link:label id="lab_arnc_GainLossOnDispositionOfAssetsNetOfTax_1B3316BD473FD618846AE244A88684EA_documentation_en-US" xlink:label="lab_arnc_GainLossOnDispositionOfAssetsNetOfTax_1B3316BD473FD618846AE244A88684EA" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Gain (loss) on disposition of assets net of tax.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_GainLossOnDispositionOfAssetsNetOfTax" xlink:label="loc_arnc_GainLossOnDispositionOfAssetsNetOfTax_1B3316BD473FD618846AE244A88684EA" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_GainLossOnDispositionOfAssetsNetOfTax_1B3316BD473FD618846AE244A88684EA" xlink:to="lab_arnc_GainLossOnDispositionOfAssetsNetOfTax_1B3316BD473FD618846AE244A88684EA" xlink:type="arc" />
    <link:label id="lab_arnc_PaymentForPensionSettlementChargesNetOfTax_585E1984E2138507BD2EE244A886169F_terseLabel_en-US" xlink:label="lab_arnc_PaymentForPensionSettlementChargesNetOfTax_585E1984E2138507BD2EE244A886169F" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Payment for pension benefits, net of tax</link:label>
    <link:label id="lab_arnc_PaymentForPensionSettlementChargesNetOfTax_585E1984E2138507BD2EE244A886169F_label_en-US" xlink:label="lab_arnc_PaymentForPensionSettlementChargesNetOfTax_585E1984E2138507BD2EE244A886169F" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Payment For Pension Settlement Charges, Net Of Tax</link:label>
    <link:label id="lab_arnc_PaymentForPensionSettlementChargesNetOfTax_585E1984E2138507BD2EE244A886169F_documentation_en-US" xlink:label="lab_arnc_PaymentForPensionSettlementChargesNetOfTax_585E1984E2138507BD2EE244A886169F" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Payment For Pension Settlement Charges, Net Of Tax</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_PaymentForPensionSettlementChargesNetOfTax" xlink:label="loc_arnc_PaymentForPensionSettlementChargesNetOfTax_585E1984E2138507BD2EE244A886169F" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_PaymentForPensionSettlementChargesNetOfTax_585E1984E2138507BD2EE244A886169F" xlink:to="lab_arnc_PaymentForPensionSettlementChargesNetOfTax_585E1984E2138507BD2EE244A886169F" xlink:type="arc" />
    <link:label id="lab_us-gaap_GoodwillImpairmentLossNetOfTax_0E0AEDF483240AFABE7CE244A886CD10_terseLabel_en-US" xlink:label="lab_us-gaap_GoodwillImpairmentLossNetOfTax_0E0AEDF483240AFABE7CE244A886CD10" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Goodwill, impairment loss, net of tax</link:label>
    <link:label id="lab_us-gaap_GoodwillImpairmentLossNetOfTax_0E0AEDF483240AFABE7CE244A886CD10_label_en-US" xlink:label="lab_us-gaap_GoodwillImpairmentLossNetOfTax_0E0AEDF483240AFABE7CE244A886CD10" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Goodwill, Impairment Loss, Net of Tax</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_GoodwillImpairmentLossNetOfTax" xlink:label="loc_us-gaap_GoodwillImpairmentLossNetOfTax_0E0AEDF483240AFABE7CE244A886CD10" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_GoodwillImpairmentLossNetOfTax_0E0AEDF483240AFABE7CE244A886CD10" xlink:to="lab_us-gaap_GoodwillImpairmentLossNetOfTax_0E0AEDF483240AFABE7CE244A886CD10" xlink:type="arc" />
    <link:label id="lab_us-gaap_GoodwillImpairmentLoss_BC1EDDD67B509C0F2C8AE244A886A88A_verboseLabel_en-US" xlink:label="lab_us-gaap_GoodwillImpairmentLoss_BC1EDDD67B509C0F2C8AE244A886A88A" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Impairment of goodwill (A and O)</link:label>
    <link:label id="lab_us-gaap_GoodwillImpairmentLoss_BC1EDDD67B509C0F2C8AE244A886A88A_label_en-US" xlink:label="lab_us-gaap_GoodwillImpairmentLoss_BC1EDDD67B509C0F2C8AE244A886A88A" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Goodwill, Impairment Loss</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_GoodwillImpairmentLoss" xlink:label="loc_us-gaap_GoodwillImpairmentLoss_BC1EDDD67B509C0F2C8AE244A886A88A" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_GoodwillImpairmentLoss_BC1EDDD67B509C0F2C8AE244A886A88A" xlink:to="lab_us-gaap_GoodwillImpairmentLoss_BC1EDDD67B509C0F2C8AE244A886A88A" xlink:type="arc" />
    <link:label id="lab_arnc_TaxCutsAndJobsActOf2017IncompleteAccountingProvisionalIncomeTaxExpenseBenefit_006B39725D8DD0DF4AA0E244A886E2E2_terseLabel_en-US" xlink:label="lab_arnc_TaxCutsAndJobsActOf2017IncompleteAccountingProvisionalIncomeTaxExpenseBenefit_006B39725D8DD0DF4AA0E244A886E2E2" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Tax cuts and jobs act of 2017, incomplete accounting, provisional income tax expense (benefit)</link:label>
    <link:label id="lab_arnc_TaxCutsAndJobsActOf2017IncompleteAccountingProvisionalIncomeTaxExpenseBenefit_006B39725D8DD0DF4AA0E244A886E2E2_label_en-US" xlink:label="lab_arnc_TaxCutsAndJobsActOf2017IncompleteAccountingProvisionalIncomeTaxExpenseBenefit_006B39725D8DD0DF4AA0E244A886E2E2" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Tax Cuts And Jobs Act Of 2017, Incomplete Accounting, Provisional Income Tax Expense (Benefit)</link:label>
    <link:label id="lab_arnc_TaxCutsAndJobsActOf2017IncompleteAccountingProvisionalIncomeTaxExpenseBenefit_006B39725D8DD0DF4AA0E244A886E2E2_documentation_en-US" xlink:label="lab_arnc_TaxCutsAndJobsActOf2017IncompleteAccountingProvisionalIncomeTaxExpenseBenefit_006B39725D8DD0DF4AA0E244A886E2E2" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Tax Cuts And Jobs Act Of 2017, Incomplete Accounting, Provisional Income Tax Expense (Benefit)</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_TaxCutsAndJobsActOf2017IncompleteAccountingProvisionalIncomeTaxExpenseBenefit" xlink:label="loc_arnc_TaxCutsAndJobsActOf2017IncompleteAccountingProvisionalIncomeTaxExpenseBenefit_006B39725D8DD0DF4AA0E244A886E2E2" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_TaxCutsAndJobsActOf2017IncompleteAccountingProvisionalIncomeTaxExpenseBenefit_006B39725D8DD0DF4AA0E244A886E2E2" xlink:to="lab_arnc_TaxCutsAndJobsActOf2017IncompleteAccountingProvisionalIncomeTaxExpenseBenefit_006B39725D8DD0DF4AA0E244A886E2E2" xlink:type="arc" />
    <link:label id="lab_arnc_BusinessCombinationContingentConsiderationArrangementsChangeInAmountOfContingentConsiderationLiabilityNetOfTax_0BD4C74734DBDA9AA1F8E244A88688A2_negatedLabel_en-US" xlink:label="lab_arnc_BusinessCombinationContingentConsiderationArrangementsChangeInAmountOfContingentConsiderationLiabilityNetOfTax_0BD4C74734DBDA9AA1F8E244A88688A2" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xml:lang="en-US">Business combination, contingent consideration arrangements, change in amount of contingent consideration, liability, net of tax</link:label>
    <link:label id="lab_arnc_BusinessCombinationContingentConsiderationArrangementsChangeInAmountOfContingentConsiderationLiabilityNetOfTax_0BD4C74734DBDA9AA1F8E244A88688A2_label_en-US" xlink:label="lab_arnc_BusinessCombinationContingentConsiderationArrangementsChangeInAmountOfContingentConsiderationLiabilityNetOfTax_0BD4C74734DBDA9AA1F8E244A88688A2" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Business Combination, Contingent Consideration Arrangements, Change In Amount Of Contingent Consideration, Liability, Net Of Tax</link:label>
    <link:label id="lab_arnc_BusinessCombinationContingentConsiderationArrangementsChangeInAmountOfContingentConsiderationLiabilityNetOfTax_0BD4C74734DBDA9AA1F8E244A88688A2_documentation_en-US" xlink:label="lab_arnc_BusinessCombinationContingentConsiderationArrangementsChangeInAmountOfContingentConsiderationLiabilityNetOfTax_0BD4C74734DBDA9AA1F8E244A88688A2" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Business Combination, Contingent Consideration Arrangements, Change In Amount Of Contingent Consideration, Liability, Net Of Tax</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_BusinessCombinationContingentConsiderationArrangementsChangeInAmountOfContingentConsiderationLiabilityNetOfTax" xlink:label="loc_arnc_BusinessCombinationContingentConsiderationArrangementsChangeInAmountOfContingentConsiderationLiabilityNetOfTax_0BD4C74734DBDA9AA1F8E244A88688A2" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_BusinessCombinationContingentConsiderationArrangementsChangeInAmountOfContingentConsiderationLiabilityNetOfTax_0BD4C74734DBDA9AA1F8E244A88688A2" xlink:to="lab_arnc_BusinessCombinationContingentConsiderationArrangementsChangeInAmountOfContingentConsiderationLiabilityNetOfTax_0BD4C74734DBDA9AA1F8E244A88688A2" xlink:type="arc" />
    <link:label id="lab_us-gaap_BusinessCombinationContingentConsiderationArrangementsChangeInAmountOfContingentConsiderationLiability1_77CA609DBA19D21CCEBFE244A88605FE_negatedLabel_en-US" xlink:label="lab_us-gaap_BusinessCombinationContingentConsiderationArrangementsChangeInAmountOfContingentConsiderationLiability1_77CA609DBA19D21CCEBFE244A88605FE" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xml:lang="en-US">Contingent consideration arrangements, change in amount of contingent consideration, liability</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_BusinessCombinationContingentConsiderationArrangementsChangeInAmountOfContingentConsiderationLiability1" xlink:label="loc_us-gaap_BusinessCombinationContingentConsiderationArrangementsChangeInAmountOfContingentConsiderationLiability1_77CA609DBA19D21CCEBFE244A88605FE" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_BusinessCombinationContingentConsiderationArrangementsChangeInAmountOfContingentConsiderationLiability1_77CA609DBA19D21CCEBFE244A88605FE" xlink:to="lab_us-gaap_BusinessCombinationContingentConsiderationArrangementsChangeInAmountOfContingentConsiderationLiability1_77CA609DBA19D21CCEBFE244A88605FE" xlink:type="arc" />
    <link:label id="lab_arnc_DisposalGroupContingentLiabilityPeriodIncreaseDecreaseNetOfTax_9813F863F8684424637BE244A886BCE6_terseLabel_en-US" xlink:label="lab_arnc_DisposalGroupContingentLiabilityPeriodIncreaseDecreaseNetOfTax_9813F863F8684424637BE244A886BCE6" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Favorable adjustment to a separation-related guarantee liability (after-tax)</link:label>
    <link:label id="lab_arnc_DisposalGroupContingentLiabilityPeriodIncreaseDecreaseNetOfTax_9813F863F8684424637BE244A886BCE6_label_en-US" xlink:label="lab_arnc_DisposalGroupContingentLiabilityPeriodIncreaseDecreaseNetOfTax_9813F863F8684424637BE244A886BCE6" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Disposal Group, Contingent Liability, Period Increase (Decrease), Net Of Tax</link:label>
    <link:label id="lab_arnc_DisposalGroupContingentLiabilityPeriodIncreaseDecreaseNetOfTax_9813F863F8684424637BE244A886BCE6_documentation_en-US" xlink:label="lab_arnc_DisposalGroupContingentLiabilityPeriodIncreaseDecreaseNetOfTax_9813F863F8684424637BE244A886BCE6" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Disposal Group, Contingent Liability, Period Increase (Decrease), Net Of Tax</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_DisposalGroupContingentLiabilityPeriodIncreaseDecreaseNetOfTax" xlink:label="loc_arnc_DisposalGroupContingentLiabilityPeriodIncreaseDecreaseNetOfTax_9813F863F8684424637BE244A886BCE6" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_DisposalGroupContingentLiabilityPeriodIncreaseDecreaseNetOfTax_9813F863F8684424637BE244A886BCE6" xlink:to="lab_arnc_DisposalGroupContingentLiabilityPeriodIncreaseDecreaseNetOfTax_9813F863F8684424637BE244A886BCE6" xlink:type="arc" />
    <link:label id="lab_arnc_DisposalGroupContingentLiabilityPeriodIncreaseDecrease_A578CF3E26BA3F3294D0E244A8864B4E_terseLabel_en-US" xlink:label="lab_arnc_DisposalGroupContingentLiabilityPeriodIncreaseDecrease_A578CF3E26BA3F3294D0E244A8864B4E" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Favorable adjustment to a separation-related guarantee liability (pre-tax)</link:label>
    <link:label id="lab_arnc_DisposalGroupContingentLiabilityPeriodIncreaseDecrease_A578CF3E26BA3F3294D0E244A8864B4E_label_en-US" xlink:label="lab_arnc_DisposalGroupContingentLiabilityPeriodIncreaseDecrease_A578CF3E26BA3F3294D0E244A8864B4E" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Disposal Group, Contingent Liability, Period Increase (Decrease)</link:label>
    <link:label id="lab_arnc_DisposalGroupContingentLiabilityPeriodIncreaseDecrease_A578CF3E26BA3F3294D0E244A8864B4E_documentation_en-US" xlink:label="lab_arnc_DisposalGroupContingentLiabilityPeriodIncreaseDecrease_A578CF3E26BA3F3294D0E244A8864B4E" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Disposal Group, Contingent Liability, Period Increase (Decrease)</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_DisposalGroupContingentLiabilityPeriodIncreaseDecrease" xlink:label="loc_arnc_DisposalGroupContingentLiabilityPeriodIncreaseDecrease_A578CF3E26BA3F3294D0E244A8864B4E" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_DisposalGroupContingentLiabilityPeriodIncreaseDecrease_A578CF3E26BA3F3294D0E244A8864B4E" xlink:to="lab_arnc_DisposalGroupContingentLiabilityPeriodIncreaseDecrease_A578CF3E26BA3F3294D0E244A8864B4E" xlink:type="arc" />
    <link:label id="lab_us-gaap_DefinedBenefitPlansAndOtherPostretirementBenefitPlansDisclosuresTable_634D221C7CFC7C0DD13DBB6343733C7F_terseLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlansAndOtherPostretirementBenefitPlansDisclosuresTable_634D221C7CFC7C0DD13DBB6343733C7F" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Defined Benefit Plans and Other Postretirement Benefit Plans Disclosures [Table]</link:label>
    <link:label id="lab_us-gaap_DefinedBenefitPlansAndOtherPostretirementBenefitPlansDisclosuresTable_634D221C7CFC7C0DD13DBB6343733C7F_label_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlansAndOtherPostretirementBenefitPlansDisclosuresTable_634D221C7CFC7C0DD13DBB6343733C7F" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Benefit Plans and Other Postretirement Benefit Plans Disclosures [Table]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DefinedBenefitPlansAndOtherPostretirementBenefitPlansDisclosuresTable" xlink:label="loc_us-gaap_DefinedBenefitPlansAndOtherPostretirementBenefitPlansDisclosuresTable_634D221C7CFC7C0DD13DBB6343733C7F" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlansAndOtherPostretirementBenefitPlansDisclosuresTable_634D221C7CFC7C0DD13DBB6343733C7F" xlink:to="lab_us-gaap_DefinedBenefitPlansAndOtherPostretirementBenefitPlansDisclosuresTable_634D221C7CFC7C0DD13DBB6343733C7F" xlink:type="arc" />
    <link:label id="lab_srt_MinimumMember_AA0F0D3624145600EF2EBB634377C922_terseLabel_en-US" xlink:label="lab_srt_MinimumMember_AA0F0D3624145600EF2EBB634377C922" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Minimum</link:label>
    <link:label id="lab_srt_MinimumMember_AA0F0D3624145600EF2EBB634377C922_label_en-US" xlink:label="lab_srt_MinimumMember_AA0F0D3624145600EF2EBB634377C922" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Minimum [Member]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_MinimumMember" xlink:label="loc_srt_MinimumMember_AA0F0D3624145600EF2EBB634377C922" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_srt_MinimumMember_AA0F0D3624145600EF2EBB634377C922" xlink:to="lab_srt_MinimumMember_AA0F0D3624145600EF2EBB634377C922" xlink:type="arc" />
    <link:label id="lab_us-gaap_DefinedBenefitPlansAndOtherPostretirementBenefitPlansTableTextBlockLineItems_B5FF16E49894FAAB92A0BB634377811F_terseLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlansAndOtherPostretirementBenefitPlansTableTextBlockLineItems_B5FF16E49894FAAB92A0BB634377811F" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]</link:label>
    <link:label id="lab_us-gaap_DefinedBenefitPlansAndOtherPostretirementBenefitPlansTableTextBlockLineItems_B5FF16E49894FAAB92A0BB634377811F_label_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlansAndOtherPostretirementBenefitPlansTableTextBlockLineItems_B5FF16E49894FAAB92A0BB634377811F" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DefinedBenefitPlansAndOtherPostretirementBenefitPlansTableTextBlockLineItems" xlink:label="loc_us-gaap_DefinedBenefitPlansAndOtherPostretirementBenefitPlansTableTextBlockLineItems_B5FF16E49894FAAB92A0BB634377811F" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlansAndOtherPostretirementBenefitPlansTableTextBlockLineItems_B5FF16E49894FAAB92A0BB634377811F" xlink:to="lab_us-gaap_DefinedBenefitPlansAndOtherPostretirementBenefitPlansTableTextBlockLineItems_B5FF16E49894FAAB92A0BB634377811F" xlink:type="arc" />
    <link:label id="lab_us-gaap_DefinedBenefitPlanHealthCareCostTrendRateAssumedNextFiscalYear_0ACE83F7EF15E7B3F25CBB634377A183_terseLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanHealthCareCostTrendRateAssumedNextFiscalYear_0ACE83F7EF15E7B3F25CBB634377A183" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Health care cost trend rate assumed for next year</link:label>
    <link:label id="lab_us-gaap_DefinedBenefitPlanHealthCareCostTrendRateAssumedNextFiscalYear_0ACE83F7EF15E7B3F25CBB634377A183_label_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanHealthCareCostTrendRateAssumedNextFiscalYear_0ACE83F7EF15E7B3F25CBB634377A183" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Health Care Cost Trend Rate Assumed, Next Fiscal Year</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DefinedBenefitPlanHealthCareCostTrendRateAssumedNextFiscalYear" xlink:label="loc_us-gaap_DefinedBenefitPlanHealthCareCostTrendRateAssumedNextFiscalYear_0ACE83F7EF15E7B3F25CBB634377A183" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanHealthCareCostTrendRateAssumedNextFiscalYear_0ACE83F7EF15E7B3F25CBB634377A183" xlink:to="lab_us-gaap_DefinedBenefitPlanHealthCareCostTrendRateAssumedNextFiscalYear_0ACE83F7EF15E7B3F25CBB634377A183" xlink:type="arc" />
    <link:label id="lab_us-gaap_DefinedBenefitPlanUltimateHealthCareCostTrendRate1_E68230BE19862C96B44FBB6343778B27_verboseLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanUltimateHealthCareCostTrendRate1_E68230BE19862C96B44FBB6343778B27" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Rate to which the cost trend rate gradually declines</link:label>
    <link:label id="lab_us-gaap_DefinedBenefitPlanUltimateHealthCareCostTrendRate1_E68230BE19862C96B44FBB6343778B27_label_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanUltimateHealthCareCostTrendRate1_E68230BE19862C96B44FBB6343778B27" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Ultimate Health Care Cost Trend Rate</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DefinedBenefitPlanUltimateHealthCareCostTrendRate1" xlink:label="loc_us-gaap_DefinedBenefitPlanUltimateHealthCareCostTrendRate1_E68230BE19862C96B44FBB6343778B27" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanUltimateHealthCareCostTrendRate1_E68230BE19862C96B44FBB6343778B27" xlink:to="lab_us-gaap_DefinedBenefitPlanUltimateHealthCareCostTrendRate1_E68230BE19862C96B44FBB6343778B27" xlink:type="arc" />
    <link:label id="lab_us-gaap_DefinedBenefitPlanYearHealthCareCostTrendRateReachesUltimateTrendRate_3A50D996E5ED3C3C1C05BB634377DE8B_terseLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanYearHealthCareCostTrendRateReachesUltimateTrendRate_3A50D996E5ED3C3C1C05BB634377DE8B" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Year that the rate reaches the rate at which it is assumed to remain</link:label>
    <link:label id="lab_us-gaap_DefinedBenefitPlanYearHealthCareCostTrendRateReachesUltimateTrendRate_3A50D996E5ED3C3C1C05BB634377DE8B_label_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanYearHealthCareCostTrendRateReachesUltimateTrendRate_3A50D996E5ED3C3C1C05BB634377DE8B" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Year Health Care Cost Trend Rate Reaches Ultimate Trend Rate</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DefinedBenefitPlanYearHealthCareCostTrendRateReachesUltimateTrendRate" xlink:label="loc_us-gaap_DefinedBenefitPlanYearHealthCareCostTrendRateReachesUltimateTrendRate_3A50D996E5ED3C3C1C05BB634377DE8B" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanYearHealthCareCostTrendRateReachesUltimateTrendRate_3A50D996E5ED3C3C1C05BB634377DE8B" xlink:to="lab_us-gaap_DefinedBenefitPlanYearHealthCareCostTrendRateReachesUltimateTrendRate_3A50D996E5ED3C3C1C05BB634377DE8B" xlink:type="arc" />
    <link:label id="lab_arnc_NoOfYearOverActualAnnualHealthcareCostTrendExperience_3F36F70AD0775E839475BB63437757DD_terseLabel_en-US" xlink:label="lab_arnc_NoOfYearOverActualAnnualHealthcareCostTrendExperience_3F36F70AD0775E839475BB63437757DD" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Number of years over actual annual healthcare cost trend experience</link:label>
    <link:label id="lab_arnc_NoOfYearOverActualAnnualHealthcareCostTrendExperience_3F36F70AD0775E839475BB63437757DD_label_en-US" xlink:label="lab_arnc_NoOfYearOverActualAnnualHealthcareCostTrendExperience_3F36F70AD0775E839475BB63437757DD" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">No Of Year Over Actual Annual Healthcare Cost Trend Experience</link:label>
    <link:label id="lab_arnc_NoOfYearOverActualAnnualHealthcareCostTrendExperience_3F36F70AD0775E839475BB63437757DD_documentation_en-US" xlink:label="lab_arnc_NoOfYearOverActualAnnualHealthcareCostTrendExperience_3F36F70AD0775E839475BB63437757DD" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">No of year over actual annual health care cost trend experience.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_NoOfYearOverActualAnnualHealthcareCostTrendExperience" xlink:label="loc_arnc_NoOfYearOverActualAnnualHealthcareCostTrendExperience_3F36F70AD0775E839475BB63437757DD" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_NoOfYearOverActualAnnualHealthcareCostTrendExperience_3F36F70AD0775E839475BB63437757DD" xlink:to="lab_arnc_NoOfYearOverActualAnnualHealthcareCostTrendExperience_3F36F70AD0775E839475BB63437757DD" xlink:type="arc" />
    <link:label id="lab_arnc_DocumentAndEntityInformationAbstract_586541E2A94142457769E248CED8D3BC_label_en-US" xlink:label="lab_arnc_DocumentAndEntityInformationAbstract_586541E2A94142457769E248CED8D3BC" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Document And Entity Information [Abstract]</link:label>
    <link:label id="lab_arnc_DocumentAndEntityInformationAbstract_586541E2A94142457769E248CED8D3BC_documentation_en-US" xlink:label="lab_arnc_DocumentAndEntityInformationAbstract_586541E2A94142457769E248CED8D3BC" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Document and Entity Information [Abstract]</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_DocumentAndEntityInformationAbstract" xlink:label="loc_arnc_DocumentAndEntityInformationAbstract_586541E2A94142457769E248CED8D3BC" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_DocumentAndEntityInformationAbstract_586541E2A94142457769E248CED8D3BC" xlink:to="lab_arnc_DocumentAndEntityInformationAbstract_586541E2A94142457769E248CED8D3BC" xlink:type="arc" />
    <link:label id="lab_dei_DocumentType_295D1C11DFF9100FB7C2E248CED8E0FC_terseLabel_en-US" xlink:label="lab_dei_DocumentType_295D1C11DFF9100FB7C2E248CED8E0FC" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Document Type</link:label>
    <link:label id="lab_dei_DocumentType_295D1C11DFF9100FB7C2E248CED8E0FC_label_en-US" xlink:label="lab_dei_DocumentType_295D1C11DFF9100FB7C2E248CED8E0FC" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Document Type</link:label>
    <link:loc xlink:href="https://xbrl.sec.gov/dei/2018/dei-2018-01-31.xsd#dei_DocumentType" xlink:label="loc_dei_DocumentType_295D1C11DFF9100FB7C2E248CED8E0FC" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_dei_DocumentType_295D1C11DFF9100FB7C2E248CED8E0FC" xlink:to="lab_dei_DocumentType_295D1C11DFF9100FB7C2E248CED8E0FC" xlink:type="arc" />
    <link:label id="lab_dei_AmendmentFlag_BDCE9994A792E1709261E248CED8C7E2_terseLabel_en-US" xlink:label="lab_dei_AmendmentFlag_BDCE9994A792E1709261E248CED8C7E2" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Amendment Flag</link:label>
    <link:label id="lab_dei_AmendmentFlag_BDCE9994A792E1709261E248CED8C7E2_label_en-US" xlink:label="lab_dei_AmendmentFlag_BDCE9994A792E1709261E248CED8C7E2" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Amendment Flag</link:label>
    <link:loc xlink:href="https://xbrl.sec.gov/dei/2018/dei-2018-01-31.xsd#dei_AmendmentFlag" xlink:label="loc_dei_AmendmentFlag_BDCE9994A792E1709261E248CED8C7E2" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_dei_AmendmentFlag_BDCE9994A792E1709261E248CED8C7E2" xlink:to="lab_dei_AmendmentFlag_BDCE9994A792E1709261E248CED8C7E2" xlink:type="arc" />
    <link:label id="lab_dei_DocumentPeriodEndDate_94BA86F4949B74E40934E248CED8BB2C_terseLabel_en-US" xlink:label="lab_dei_DocumentPeriodEndDate_94BA86F4949B74E40934E248CED8BB2C" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Document Period End Date</link:label>
    <link:label id="lab_dei_DocumentPeriodEndDate_94BA86F4949B74E40934E248CED8BB2C_label_en-US" xlink:label="lab_dei_DocumentPeriodEndDate_94BA86F4949B74E40934E248CED8BB2C" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Document Period End Date</link:label>
    <link:loc xlink:href="https://xbrl.sec.gov/dei/2018/dei-2018-01-31.xsd#dei_DocumentPeriodEndDate" xlink:label="loc_dei_DocumentPeriodEndDate_94BA86F4949B74E40934E248CED8BB2C" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_dei_DocumentPeriodEndDate_94BA86F4949B74E40934E248CED8BB2C" xlink:to="lab_dei_DocumentPeriodEndDate_94BA86F4949B74E40934E248CED8BB2C" xlink:type="arc" />
    <link:label id="lab_dei_DocumentFiscalYearFocus_973A703EE994C9CB3447E248CED83537_terseLabel_en-US" xlink:label="lab_dei_DocumentFiscalYearFocus_973A703EE994C9CB3447E248CED83537" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Document Fiscal Year Focus</link:label>
    <link:label id="lab_dei_DocumentFiscalYearFocus_973A703EE994C9CB3447E248CED83537_label_en-US" xlink:label="lab_dei_DocumentFiscalYearFocus_973A703EE994C9CB3447E248CED83537" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Document Fiscal Year Focus</link:label>
    <link:loc xlink:href="https://xbrl.sec.gov/dei/2018/dei-2018-01-31.xsd#dei_DocumentFiscalYearFocus" xlink:label="loc_dei_DocumentFiscalYearFocus_973A703EE994C9CB3447E248CED83537" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_dei_DocumentFiscalYearFocus_973A703EE994C9CB3447E248CED83537" xlink:to="lab_dei_DocumentFiscalYearFocus_973A703EE994C9CB3447E248CED83537" xlink:type="arc" />
    <link:label id="lab_dei_DocumentFiscalPeriodFocus_4EEEE839CFF07C1DF1B5E248CED8FAFA_terseLabel_en-US" xlink:label="lab_dei_DocumentFiscalPeriodFocus_4EEEE839CFF07C1DF1B5E248CED8FAFA" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Document Fiscal Period Focus</link:label>
    <link:label id="lab_dei_DocumentFiscalPeriodFocus_4EEEE839CFF07C1DF1B5E248CED8FAFA_label_en-US" xlink:label="lab_dei_DocumentFiscalPeriodFocus_4EEEE839CFF07C1DF1B5E248CED8FAFA" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Document Fiscal Period Focus</link:label>
    <link:loc xlink:href="https://xbrl.sec.gov/dei/2018/dei-2018-01-31.xsd#dei_DocumentFiscalPeriodFocus" xlink:label="loc_dei_DocumentFiscalPeriodFocus_4EEEE839CFF07C1DF1B5E248CED8FAFA" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_dei_DocumentFiscalPeriodFocus_4EEEE839CFF07C1DF1B5E248CED8FAFA" xlink:to="lab_dei_DocumentFiscalPeriodFocus_4EEEE839CFF07C1DF1B5E248CED8FAFA" xlink:type="arc" />
    <link:label id="lab_dei_TradingSymbol_64634CB68B92DE7F0BFDE248CED81D68_terseLabel_en-US" xlink:label="lab_dei_TradingSymbol_64634CB68B92DE7F0BFDE248CED81D68" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Trading Symbol</link:label>
    <link:label id="lab_dei_TradingSymbol_64634CB68B92DE7F0BFDE248CED81D68_label_en-US" xlink:label="lab_dei_TradingSymbol_64634CB68B92DE7F0BFDE248CED81D68" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Trading Symbol</link:label>
    <link:loc xlink:href="https://xbrl.sec.gov/dei/2018/dei-2018-01-31.xsd#dei_TradingSymbol" xlink:label="loc_dei_TradingSymbol_64634CB68B92DE7F0BFDE248CED81D68" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_dei_TradingSymbol_64634CB68B92DE7F0BFDE248CED81D68" xlink:to="lab_dei_TradingSymbol_64634CB68B92DE7F0BFDE248CED81D68" xlink:type="arc" />
    <link:label id="lab_dei_EntityRegistrantName_4FE1568348D596095E53E248CED846D8_terseLabel_en-US" xlink:label="lab_dei_EntityRegistrantName_4FE1568348D596095E53E248CED846D8" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Entity Registrant Name</link:label>
    <link:label id="lab_dei_EntityRegistrantName_4FE1568348D596095E53E248CED846D8_label_en-US" xlink:label="lab_dei_EntityRegistrantName_4FE1568348D596095E53E248CED846D8" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Entity Registrant Name</link:label>
    <link:loc xlink:href="https://xbrl.sec.gov/dei/2018/dei-2018-01-31.xsd#dei_EntityRegistrantName" xlink:label="loc_dei_EntityRegistrantName_4FE1568348D596095E53E248CED846D8" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_dei_EntityRegistrantName_4FE1568348D596095E53E248CED846D8" xlink:to="lab_dei_EntityRegistrantName_4FE1568348D596095E53E248CED846D8" xlink:type="arc" />
    <link:label id="lab_dei_EntityCentralIndexKey_0B294FAF32AAB64A621EE248CED81258_terseLabel_en-US" xlink:label="lab_dei_EntityCentralIndexKey_0B294FAF32AAB64A621EE248CED81258" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Entity Central Index Key</link:label>
    <link:label id="lab_dei_EntityCentralIndexKey_0B294FAF32AAB64A621EE248CED81258_label_en-US" xlink:label="lab_dei_EntityCentralIndexKey_0B294FAF32AAB64A621EE248CED81258" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Entity Central Index Key</link:label>
    <link:loc xlink:href="https://xbrl.sec.gov/dei/2018/dei-2018-01-31.xsd#dei_EntityCentralIndexKey" xlink:label="loc_dei_EntityCentralIndexKey_0B294FAF32AAB64A621EE248CED81258" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_dei_EntityCentralIndexKey_0B294FAF32AAB64A621EE248CED81258" xlink:to="lab_dei_EntityCentralIndexKey_0B294FAF32AAB64A621EE248CED81258" xlink:type="arc" />
    <link:label id="lab_dei_CurrentFiscalYearEndDate_A2CC3B83A3F666BC88FBE248CED8A221_terseLabel_en-US" xlink:label="lab_dei_CurrentFiscalYearEndDate_A2CC3B83A3F666BC88FBE248CED8A221" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Current Fiscal Year End Date</link:label>
    <link:label id="lab_dei_CurrentFiscalYearEndDate_A2CC3B83A3F666BC88FBE248CED8A221_label_en-US" xlink:label="lab_dei_CurrentFiscalYearEndDate_A2CC3B83A3F666BC88FBE248CED8A221" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Current Fiscal Year End Date</link:label>
    <link:loc xlink:href="https://xbrl.sec.gov/dei/2018/dei-2018-01-31.xsd#dei_CurrentFiscalYearEndDate" xlink:label="loc_dei_CurrentFiscalYearEndDate_A2CC3B83A3F666BC88FBE248CED8A221" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_dei_CurrentFiscalYearEndDate_A2CC3B83A3F666BC88FBE248CED8A221" xlink:to="lab_dei_CurrentFiscalYearEndDate_A2CC3B83A3F666BC88FBE248CED8A221" xlink:type="arc" />
    <link:label id="lab_dei_EntityWellKnownSeasonedIssuer_9F7A8E2D5B15717F9080E248CED89F04_terseLabel_en-US" xlink:label="lab_dei_EntityWellKnownSeasonedIssuer_9F7A8E2D5B15717F9080E248CED89F04" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Entity Well-known Seasoned Issuer</link:label>
    <link:label id="lab_dei_EntityWellKnownSeasonedIssuer_9F7A8E2D5B15717F9080E248CED89F04_label_en-US" xlink:label="lab_dei_EntityWellKnownSeasonedIssuer_9F7A8E2D5B15717F9080E248CED89F04" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Entity Well-known Seasoned Issuer</link:label>
    <link:loc xlink:href="https://xbrl.sec.gov/dei/2018/dei-2018-01-31.xsd#dei_EntityWellKnownSeasonedIssuer" xlink:label="loc_dei_EntityWellKnownSeasonedIssuer_9F7A8E2D5B15717F9080E248CED89F04" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_dei_EntityWellKnownSeasonedIssuer_9F7A8E2D5B15717F9080E248CED89F04" xlink:to="lab_dei_EntityWellKnownSeasonedIssuer_9F7A8E2D5B15717F9080E248CED89F04" xlink:type="arc" />
    <link:label id="lab_dei_EntityCurrentReportingStatus_1FA7FDE28420803B4C30E248CED81F9A_terseLabel_en-US" xlink:label="lab_dei_EntityCurrentReportingStatus_1FA7FDE28420803B4C30E248CED81F9A" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Entity Current Reporting Status</link:label>
    <link:label id="lab_dei_EntityCurrentReportingStatus_1FA7FDE28420803B4C30E248CED81F9A_label_en-US" xlink:label="lab_dei_EntityCurrentReportingStatus_1FA7FDE28420803B4C30E248CED81F9A" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Entity Current Reporting Status</link:label>
    <link:loc xlink:href="https://xbrl.sec.gov/dei/2018/dei-2018-01-31.xsd#dei_EntityCurrentReportingStatus" xlink:label="loc_dei_EntityCurrentReportingStatus_1FA7FDE28420803B4C30E248CED81F9A" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_dei_EntityCurrentReportingStatus_1FA7FDE28420803B4C30E248CED81F9A" xlink:to="lab_dei_EntityCurrentReportingStatus_1FA7FDE28420803B4C30E248CED81F9A" xlink:type="arc" />
    <link:label id="lab_dei_EntityVoluntaryFilers_4DAECAAD0D0AF6CBB6C2E248CED8D97F_terseLabel_en-US" xlink:label="lab_dei_EntityVoluntaryFilers_4DAECAAD0D0AF6CBB6C2E248CED8D97F" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Entity Voluntary Filers</link:label>
    <link:label id="lab_dei_EntityVoluntaryFilers_4DAECAAD0D0AF6CBB6C2E248CED8D97F_label_en-US" xlink:label="lab_dei_EntityVoluntaryFilers_4DAECAAD0D0AF6CBB6C2E248CED8D97F" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Entity Voluntary Filers</link:label>
    <link:loc xlink:href="https://xbrl.sec.gov/dei/2018/dei-2018-01-31.xsd#dei_EntityVoluntaryFilers" xlink:label="loc_dei_EntityVoluntaryFilers_4DAECAAD0D0AF6CBB6C2E248CED8D97F" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_dei_EntityVoluntaryFilers_4DAECAAD0D0AF6CBB6C2E248CED8D97F" xlink:to="lab_dei_EntityVoluntaryFilers_4DAECAAD0D0AF6CBB6C2E248CED8D97F" xlink:type="arc" />
    <link:label id="lab_dei_EntityFilerCategory_AB20FDE3392AD579DB03E248CED8B963_terseLabel_en-US" xlink:label="lab_dei_EntityFilerCategory_AB20FDE3392AD579DB03E248CED8B963" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Entity Filer Category</link:label>
    <link:label id="lab_dei_EntityFilerCategory_AB20FDE3392AD579DB03E248CED8B963_label_en-US" xlink:label="lab_dei_EntityFilerCategory_AB20FDE3392AD579DB03E248CED8B963" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Entity Filer Category</link:label>
    <link:loc xlink:href="https://xbrl.sec.gov/dei/2018/dei-2018-01-31.xsd#dei_EntityFilerCategory" xlink:label="loc_dei_EntityFilerCategory_AB20FDE3392AD579DB03E248CED8B963" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_dei_EntityFilerCategory_AB20FDE3392AD579DB03E248CED8B963" xlink:to="lab_dei_EntityFilerCategory_AB20FDE3392AD579DB03E248CED8B963" xlink:type="arc" />
    <link:label id="lab_dei_EntityCommonStockSharesOutstanding_640CF8FA3BDAF0C860D9E248CED89488_terseLabel_en-US" xlink:label="lab_dei_EntityCommonStockSharesOutstanding_640CF8FA3BDAF0C860D9E248CED89488" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Entity Common Stock, Shares Outstanding</link:label>
    <link:label id="lab_dei_EntityCommonStockSharesOutstanding_640CF8FA3BDAF0C860D9E248CED89488_label_en-US" xlink:label="lab_dei_EntityCommonStockSharesOutstanding_640CF8FA3BDAF0C860D9E248CED89488" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Entity Common Stock, Shares Outstanding</link:label>
    <link:loc xlink:href="https://xbrl.sec.gov/dei/2018/dei-2018-01-31.xsd#dei_EntityCommonStockSharesOutstanding" xlink:label="loc_dei_EntityCommonStockSharesOutstanding_640CF8FA3BDAF0C860D9E248CED89488" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_dei_EntityCommonStockSharesOutstanding_640CF8FA3BDAF0C860D9E248CED89488" xlink:to="lab_dei_EntityCommonStockSharesOutstanding_640CF8FA3BDAF0C860D9E248CED89488" xlink:type="arc" />
    <link:label id="lab_dei_EntityPublicFloat_1D711C45383D5E7C16DCE248CED81ED3_terseLabel_en-US" xlink:label="lab_dei_EntityPublicFloat_1D711C45383D5E7C16DCE248CED81ED3" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Entity Public Float</link:label>
    <link:label id="lab_dei_EntityPublicFloat_1D711C45383D5E7C16DCE248CED81ED3_label_en-US" xlink:label="lab_dei_EntityPublicFloat_1D711C45383D5E7C16DCE248CED81ED3" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Entity Public Float</link:label>
    <link:loc xlink:href="https://xbrl.sec.gov/dei/2018/dei-2018-01-31.xsd#dei_EntityPublicFloat" xlink:label="loc_dei_EntityPublicFloat_1D711C45383D5E7C16DCE248CED81ED3" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_dei_EntityPublicFloat_1D711C45383D5E7C16DCE248CED81ED3" xlink:to="lab_dei_EntityPublicFloat_1D711C45383D5E7C16DCE248CED81ED3" xlink:type="arc" />
    <link:label id="lab_dei_EntitySmallBusiness_359F3698620AF4F1E8FBE248CEDC1710_terseLabel_en-US" xlink:label="lab_dei_EntitySmallBusiness_359F3698620AF4F1E8FBE248CEDC1710" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Entity Small Business</link:label>
    <link:label id="lab_dei_EntitySmallBusiness_359F3698620AF4F1E8FBE248CEDC1710_label_en-US" xlink:label="lab_dei_EntitySmallBusiness_359F3698620AF4F1E8FBE248CEDC1710" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Entity Small Business</link:label>
    <link:loc xlink:href="https://xbrl.sec.gov/dei/2018/dei-2018-01-31.xsd#dei_EntitySmallBusiness" xlink:label="loc_dei_EntitySmallBusiness_359F3698620AF4F1E8FBE248CEDC1710" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_dei_EntitySmallBusiness_359F3698620AF4F1E8FBE248CEDC1710" xlink:to="lab_dei_EntitySmallBusiness_359F3698620AF4F1E8FBE248CEDC1710" xlink:type="arc" />
    <link:label id="lab_dei_EntityEmergingGrowthCompany_14FAE7937F657DB07A2DE248CEDCA8C9_terseLabel_en-US" xlink:label="lab_dei_EntityEmergingGrowthCompany_14FAE7937F657DB07A2DE248CEDCA8C9" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Entity Emerging Growth Company</link:label>
    <link:label id="lab_dei_EntityEmergingGrowthCompany_14FAE7937F657DB07A2DE248CEDCA8C9_label_en-US" xlink:label="lab_dei_EntityEmergingGrowthCompany_14FAE7937F657DB07A2DE248CEDCA8C9" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Entity Emerging Growth Company</link:label>
    <link:loc xlink:href="https://xbrl.sec.gov/dei/2018/dei-2018-01-31.xsd#dei_EntityEmergingGrowthCompany" xlink:label="loc_dei_EntityEmergingGrowthCompany_14FAE7937F657DB07A2DE248CEDCA8C9" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_dei_EntityEmergingGrowthCompany_14FAE7937F657DB07A2DE248CEDCA8C9" xlink:to="lab_dei_EntityEmergingGrowthCompany_14FAE7937F657DB07A2DE248CEDCA8C9" xlink:type="arc" />
    <link:label id="lab_dei_EntityShellCompany_3D7721758873CEBC9D4CE248CEDC9C1C_terseLabel_en-US" xlink:label="lab_dei_EntityShellCompany_3D7721758873CEBC9D4CE248CEDC9C1C" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Entity Shell Company</link:label>
    <link:label id="lab_dei_EntityShellCompany_3D7721758873CEBC9D4CE248CEDC9C1C_label_en-US" xlink:label="lab_dei_EntityShellCompany_3D7721758873CEBC9D4CE248CEDC9C1C" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Entity Shell Company</link:label>
    <link:loc xlink:href="https://xbrl.sec.gov/dei/2018/dei-2018-01-31.xsd#dei_EntityShellCompany" xlink:label="loc_dei_EntityShellCompany_3D7721758873CEBC9D4CE248CEDC9C1C" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_dei_EntityShellCompany_3D7721758873CEBC9D4CE248CEDC9C1C" xlink:to="lab_dei_EntityShellCompany_3D7721758873CEBC9D4CE248CEDC9C1C" xlink:type="arc" />
    <link:label id="lab_us-gaap_MaterialReconcilingItemsMember_47D1F12DC4586079E1D506E20E488CA3_verboseLabel_en-US" xlink:label="lab_us-gaap_MaterialReconcilingItemsMember_47D1F12DC4586079E1D506E20E488CA3" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Segment Reconciling Item</link:label>
    <link:label id="lab_us-gaap_MaterialReconcilingItemsMember_47D1F12DC4586079E1D506E20E488CA3_label_en-US" xlink:label="lab_us-gaap_MaterialReconcilingItemsMember_47D1F12DC4586079E1D506E20E488CA3" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Segment Reconciling Items [Member]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_MaterialReconcilingItemsMember" xlink:label="loc_us-gaap_MaterialReconcilingItemsMember_47D1F12DC4586079E1D506E20E488CA3" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_MaterialReconcilingItemsMember_47D1F12DC4586079E1D506E20E488CA3" xlink:to="lab_us-gaap_MaterialReconcilingItemsMember_47D1F12DC4586079E1D506E20E488CA3" xlink:type="arc" />
    <link:label id="lab_arnc_SegmentReportingInformationProfitsLosses_054B1355A902AD67818A06E20E48ED8B_positiveLabel_en-US" xlink:label="lab_arnc_SegmentReportingInformationProfitsLosses_054B1355A902AD67818A06E20E48ED8B" xlink:role="http://www.xbrl.org/2003/role/positiveLabel" xlink:type="resource" xml:lang="en-US">Total segment operating profit</link:label>
    <link:label id="lab_arnc_SegmentReportingInformationProfitsLosses_054B1355A902AD67818A06E20E48ED8B_label_en-US" xlink:label="lab_arnc_SegmentReportingInformationProfitsLosses_054B1355A902AD67818A06E20E48ED8B" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Segment Reporting Information Profits Losses</link:label>
    <link:label id="lab_arnc_SegmentReportingInformationProfitsLosses_054B1355A902AD67818A06E20E48ED8B_documentation_en-US" xlink:label="lab_arnc_SegmentReportingInformationProfitsLosses_054B1355A902AD67818A06E20E48ED8B" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Segment reporting information profit loss total.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_SegmentReportingInformationProfitsLosses" xlink:label="loc_arnc_SegmentReportingInformationProfitsLosses_054B1355A902AD67818A06E20E48ED8B" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_SegmentReportingInformationProfitsLosses_054B1355A902AD67818A06E20E48ED8B" xlink:to="lab_arnc_SegmentReportingInformationProfitsLosses_054B1355A902AD67818A06E20E48ED8B" xlink:type="arc" />
    <link:label id="lab_us-gaap_GoodwillImpairmentLoss_A71161B4031B8AC8159606E20E48A660_netLabel_en-US" xlink:label="lab_us-gaap_GoodwillImpairmentLoss_A71161B4031B8AC8159606E20E48A660" xlink:role="http://www.xbrl.org/2009/role/netLabel" xlink:type="resource" xml:lang="en-US">Impairment of goodwill</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_GoodwillImpairmentLoss" xlink:label="loc_us-gaap_GoodwillImpairmentLoss_A71161B4031B8AC8159606E20E48A660" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_GoodwillImpairmentLoss_A71161B4031B8AC8159606E20E48A660" xlink:to="lab_us-gaap_GoodwillImpairmentLoss_A71161B4031B8AC8159606E20E48A660" xlink:type="arc" />
    <link:label id="lab_us-gaap_RestructuringCharges_A6B20A75872B20B7AF2406E20E48F1DC_negatedLabel_en-US" xlink:label="lab_us-gaap_RestructuringCharges_A6B20A75872B20B7AF2406E20E48F1DC" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xml:lang="en-US">Restructuring and other charges</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RestructuringCharges" xlink:label="loc_us-gaap_RestructuringCharges_A6B20A75872B20B7AF2406E20E48F1DC" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RestructuringCharges_A6B20A75872B20B7AF2406E20E48F1DC" xlink:to="lab_us-gaap_RestructuringCharges_A6B20A75872B20B7AF2406E20E48F1DC" xlink:type="arc" />
    <link:label id="lab_arnc_SegmentReportingInformationCorporateExpenses_910382A13A9870C96E9306E20E495B28_negatedLabel_en-US" xlink:label="lab_arnc_SegmentReportingInformationCorporateExpenses_910382A13A9870C96E9306E20E495B28" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xml:lang="en-US">Corporate expense</link:label>
    <link:label id="lab_arnc_SegmentReportingInformationCorporateExpenses_910382A13A9870C96E9306E20E495B28_label_en-US" xlink:label="lab_arnc_SegmentReportingInformationCorporateExpenses_910382A13A9870C96E9306E20E495B28" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Segment Reporting Information Corporate Expenses</link:label>
    <link:label id="lab_arnc_SegmentReportingInformationCorporateExpenses_910382A13A9870C96E9306E20E495B28_documentation_en-US" xlink:label="lab_arnc_SegmentReportingInformationCorporateExpenses_910382A13A9870C96E9306E20E495B28" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Segment reporting information corporate expenses.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_SegmentReportingInformationCorporateExpenses" xlink:label="loc_arnc_SegmentReportingInformationCorporateExpenses_910382A13A9870C96E9306E20E495B28" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_SegmentReportingInformationCorporateExpenses_910382A13A9870C96E9306E20E495B28" xlink:to="lab_arnc_SegmentReportingInformationCorporateExpenses_910382A13A9870C96E9306E20E495B28" xlink:type="arc" />
    <link:label id="lab_us-gaap_OperatingIncomeLoss_CA512E1FD8896CDA88C606E20E498F22_totalLabel_en-US" xlink:label="lab_us-gaap_OperatingIncomeLoss_CA512E1FD8896CDA88C606E20E498F22" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Operating income</link:label>
    <link:label id="lab_us-gaap_OperatingIncomeLoss_CA512E1FD8896CDA88C606E20E498F22_label_en-US" xlink:label="lab_us-gaap_OperatingIncomeLoss_CA512E1FD8896CDA88C606E20E498F22" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Operating Income (Loss)</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_OperatingIncomeLoss" xlink:label="loc_us-gaap_OperatingIncomeLoss_CA512E1FD8896CDA88C606E20E498F22" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OperatingIncomeLoss_CA512E1FD8896CDA88C606E20E498F22" xlink:to="lab_us-gaap_OperatingIncomeLoss_CA512E1FD8896CDA88C606E20E498F22" xlink:type="arc" />
    <link:label id="lab_us-gaap_InterestExpense_FDCF4F1487EE6F5A750A06E20E4921CF_negatedLabel_en-US" xlink:label="lab_us-gaap_InterestExpense_FDCF4F1487EE6F5A750A06E20E4921CF" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xml:lang="en-US">Interest expense</link:label>
    <link:label id="lab_us-gaap_InterestExpense_FDCF4F1487EE6F5A750A06E20E4921CF_label_en-US" xlink:label="lab_us-gaap_InterestExpense_FDCF4F1487EE6F5A750A06E20E4921CF" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Interest Expense</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_InterestExpense" xlink:label="loc_us-gaap_InterestExpense_FDCF4F1487EE6F5A750A06E20E4921CF" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_InterestExpense_FDCF4F1487EE6F5A750A06E20E4921CF" xlink:to="lab_us-gaap_InterestExpense_FDCF4F1487EE6F5A750A06E20E4921CF" xlink:type="arc" />
    <link:label id="lab_us-gaap_NonoperatingIncomeExpense_FFF182B6AF07BF9861EA06E20E49391B_terseLabel_en-US" xlink:label="lab_us-gaap_NonoperatingIncomeExpense_FFF182B6AF07BF9861EA06E20E49391B" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Other (expense) income, net</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_NonoperatingIncomeExpense" xlink:label="loc_us-gaap_NonoperatingIncomeExpense_FFF182B6AF07BF9861EA06E20E49391B" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_NonoperatingIncomeExpense_FFF182B6AF07BF9861EA06E20E49391B" xlink:to="lab_us-gaap_NonoperatingIncomeExpense_FFF182B6AF07BF9861EA06E20E49391B" xlink:type="arc" />
    <link:label id="lab_us-gaap_ScheduleOfRestructuringAndRelatedCostsTable_7E1BB9682D1941A926DDBA4BBE6BDC03_terseLabel_en-US" xlink:label="lab_us-gaap_ScheduleOfRestructuringAndRelatedCostsTable_7E1BB9682D1941A926DDBA4BBE6BDC03" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Schedule of Restructuring and Related Costs [Table]</link:label>
    <link:label id="lab_us-gaap_ScheduleOfRestructuringAndRelatedCostsTable_7E1BB9682D1941A926DDBA4BBE6BDC03_label_en-US" xlink:label="lab_us-gaap_ScheduleOfRestructuringAndRelatedCostsTable_7E1BB9682D1941A926DDBA4BBE6BDC03" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Schedule of Restructuring and Related Costs [Table]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ScheduleOfRestructuringAndRelatedCostsTable" xlink:label="loc_us-gaap_ScheduleOfRestructuringAndRelatedCostsTable_7E1BB9682D1941A926DDBA4BBE6BDC03" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfRestructuringAndRelatedCostsTable_7E1BB9682D1941A926DDBA4BBE6BDC03" xlink:to="lab_us-gaap_ScheduleOfRestructuringAndRelatedCostsTable_7E1BB9682D1941A926DDBA4BBE6BDC03" xlink:type="arc" />
    <link:label id="lab_us-gaap_RestructuringCostAndReserveLineItems_BFE1CB8CD933E4DF63CCBA4BBE6BA80B_terseLabel_en-US" xlink:label="lab_us-gaap_RestructuringCostAndReserveLineItems_BFE1CB8CD933E4DF63CCBA4BBE6BA80B" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Restructuring Cost and Reserve [Line Items]</link:label>
    <link:label id="lab_us-gaap_RestructuringCostAndReserveLineItems_BFE1CB8CD933E4DF63CCBA4BBE6BA80B_label_en-US" xlink:label="lab_us-gaap_RestructuringCostAndReserveLineItems_BFE1CB8CD933E4DF63CCBA4BBE6BA80B" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Restructuring Cost and Reserve [Line Items]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RestructuringCostAndReserveLineItems" xlink:label="loc_us-gaap_RestructuringCostAndReserveLineItems_BFE1CB8CD933E4DF63CCBA4BBE6BA80B" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RestructuringCostAndReserveLineItems_BFE1CB8CD933E4DF63CCBA4BBE6BA80B" xlink:to="lab_us-gaap_RestructuringCostAndReserveLineItems_BFE1CB8CD933E4DF63CCBA4BBE6BA80B" xlink:type="arc" />
    <link:label id="lab_us-gaap_RevenueFromContractWithCustomerAbstract_D47F3253A8EC56D15545C968C3BB0193_label_en-US" xlink:label="lab_us-gaap_RevenueFromContractWithCustomerAbstract_D47F3253A8EC56D15545C968C3BB0193" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Revenue from Contract with Customer [Abstract]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RevenueFromContractWithCustomerAbstract" xlink:label="loc_us-gaap_RevenueFromContractWithCustomerAbstract_D47F3253A8EC56D15545C968C3BB0193" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RevenueFromContractWithCustomerAbstract_D47F3253A8EC56D15545C968C3BB0193" xlink:to="lab_us-gaap_RevenueFromContractWithCustomerAbstract_D47F3253A8EC56D15545C968C3BB0193" xlink:type="arc" />
    <link:label id="lab_us-gaap_RevenueFromContractWithCustomerTextBlock_215E707227225183BD54C968C3BB8374_terseLabel_en-US" xlink:label="lab_us-gaap_RevenueFromContractWithCustomerTextBlock_215E707227225183BD54C968C3BB8374" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Revenue from Contracts with Customers</link:label>
    <link:label id="lab_us-gaap_RevenueFromContractWithCustomerTextBlock_215E707227225183BD54C968C3BB8374_label_en-US" xlink:label="lab_us-gaap_RevenueFromContractWithCustomerTextBlock_215E707227225183BD54C968C3BB8374" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Revenue from Contract with Customer [Text Block]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RevenueFromContractWithCustomerTextBlock" xlink:label="loc_us-gaap_RevenueFromContractWithCustomerTextBlock_215E707227225183BD54C968C3BB8374" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RevenueFromContractWithCustomerTextBlock_215E707227225183BD54C968C3BB8374" xlink:to="lab_us-gaap_RevenueFromContractWithCustomerTextBlock_215E707227225183BD54C968C3BB8374" xlink:type="arc" />
    <link:label id="lab_arnc_ScheduleOfWeightedAverageUsefulLivesOfStructuresAndMachineryAndEquipmentTextBlock_AEA975113AF622F447029BD95B3FD711_terseLabel_en-US" xlink:label="lab_arnc_ScheduleOfWeightedAverageUsefulLivesOfStructuresAndMachineryAndEquipmentTextBlock_AEA975113AF622F447029BD95B3FD711" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Weighted-average useful lives of structures and machinery and and equipment</link:label>
    <link:label id="lab_arnc_ScheduleOfWeightedAverageUsefulLivesOfStructuresAndMachineryAndEquipmentTextBlock_AEA975113AF622F447029BD95B3FD711_label_en-US" xlink:label="lab_arnc_ScheduleOfWeightedAverageUsefulLivesOfStructuresAndMachineryAndEquipmentTextBlock_AEA975113AF622F447029BD95B3FD711" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Schedule Of Weighted Average Useful Lives Of Structures And Machinery And Equipment [Text Block]</link:label>
    <link:label id="lab_arnc_ScheduleOfWeightedAverageUsefulLivesOfStructuresAndMachineryAndEquipmentTextBlock_AEA975113AF622F447029BD95B3FD711_documentation_en-US" xlink:label="lab_arnc_ScheduleOfWeightedAverageUsefulLivesOfStructuresAndMachineryAndEquipmentTextBlock_AEA975113AF622F447029BD95B3FD711" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Schedule of weighted average useful lives of structures and machinery and equipment.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_ScheduleOfWeightedAverageUsefulLivesOfStructuresAndMachineryAndEquipmentTextBlock" xlink:label="loc_arnc_ScheduleOfWeightedAverageUsefulLivesOfStructuresAndMachineryAndEquipmentTextBlock_AEA975113AF622F447029BD95B3FD711" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_ScheduleOfWeightedAverageUsefulLivesOfStructuresAndMachineryAndEquipmentTextBlock_AEA975113AF622F447029BD95B3FD711" xlink:to="lab_arnc_ScheduleOfWeightedAverageUsefulLivesOfStructuresAndMachineryAndEquipmentTextBlock_AEA975113AF622F447029BD95B3FD711" xlink:type="arc" />
    <link:label id="lab_arnc_WeightedAverageUsefulLivesOfSoftwareAndOtherIntangibleAssetsByReportingSegmentTextBlock_CE434B2BB20BC08E02769BD95B3F7082_terseLabel_en-US" xlink:label="lab_arnc_WeightedAverageUsefulLivesOfSoftwareAndOtherIntangibleAssetsByReportingSegmentTextBlock_CE434B2BB20BC08E02769BD95B3F7082" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Weighted-average useful lives of software and other intangibles</link:label>
    <link:label id="lab_arnc_WeightedAverageUsefulLivesOfSoftwareAndOtherIntangibleAssetsByReportingSegmentTextBlock_CE434B2BB20BC08E02769BD95B3F7082_label_en-US" xlink:label="lab_arnc_WeightedAverageUsefulLivesOfSoftwareAndOtherIntangibleAssetsByReportingSegmentTextBlock_CE434B2BB20BC08E02769BD95B3F7082" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Weighted Average Useful Lives Of Software And Other Intangible Assets By Reporting Segment [Text Block]</link:label>
    <link:label id="lab_arnc_WeightedAverageUsefulLivesOfSoftwareAndOtherIntangibleAssetsByReportingSegmentTextBlock_CE434B2BB20BC08E02769BD95B3F7082_documentation_en-US" xlink:label="lab_arnc_WeightedAverageUsefulLivesOfSoftwareAndOtherIntangibleAssetsByReportingSegmentTextBlock_CE434B2BB20BC08E02769BD95B3F7082" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Weighted average useful lives of software and other intangible assets by reporting segment.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_WeightedAverageUsefulLivesOfSoftwareAndOtherIntangibleAssetsByReportingSegmentTextBlock" xlink:label="loc_arnc_WeightedAverageUsefulLivesOfSoftwareAndOtherIntangibleAssetsByReportingSegmentTextBlock_CE434B2BB20BC08E02769BD95B3F7082" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_WeightedAverageUsefulLivesOfSoftwareAndOtherIntangibleAssetsByReportingSegmentTextBlock_CE434B2BB20BC08E02769BD95B3F7082" xlink:to="lab_arnc_WeightedAverageUsefulLivesOfSoftwareAndOtherIntangibleAssetsByReportingSegmentTextBlock_CE434B2BB20BC08E02769BD95B3F7082" xlink:type="arc" />
    <link:label id="lab_us-gaap_SubsequentEventsAbstract_712B549547BB80B21048073B4F84DC2C_label_en-US" xlink:label="lab_us-gaap_SubsequentEventsAbstract_712B549547BB80B21048073B4F84DC2C" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Subsequent Events [Abstract]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_SubsequentEventsAbstract" xlink:label="loc_us-gaap_SubsequentEventsAbstract_712B549547BB80B21048073B4F84DC2C" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SubsequentEventsAbstract_712B549547BB80B21048073B4F84DC2C" xlink:to="lab_us-gaap_SubsequentEventsAbstract_712B549547BB80B21048073B4F84DC2C" xlink:type="arc" />
    <link:label id="lab_us-gaap_SubsequentEventTable_5F536BA2DD7AAC5E9C3C073B4F84F9AE_terseLabel_en-US" xlink:label="lab_us-gaap_SubsequentEventTable_5F536BA2DD7AAC5E9C3C073B4F84F9AE" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Subsequent Event [Table]</link:label>
    <link:label id="lab_us-gaap_SubsequentEventTable_5F536BA2DD7AAC5E9C3C073B4F84F9AE_label_en-US" xlink:label="lab_us-gaap_SubsequentEventTable_5F536BA2DD7AAC5E9C3C073B4F84F9AE" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Subsequent Event [Table]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_SubsequentEventTable" xlink:label="loc_us-gaap_SubsequentEventTable_5F536BA2DD7AAC5E9C3C073B4F84F9AE" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SubsequentEventTable_5F536BA2DD7AAC5E9C3C073B4F84F9AE" xlink:to="lab_us-gaap_SubsequentEventTable_5F536BA2DD7AAC5E9C3C073B4F84F9AE" xlink:type="arc" />
    <link:label id="lab_us-gaap_ShareRepurchaseProgramAxis_728F4C6FB845EBEED3E10748377BAFDC_terseLabel_en-US" xlink:label="lab_us-gaap_ShareRepurchaseProgramAxis_728F4C6FB845EBEED3E10748377BAFDC" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Share Repurchase Program [Axis]</link:label>
    <link:label id="lab_us-gaap_ShareRepurchaseProgramAxis_728F4C6FB845EBEED3E10748377BAFDC_label_en-US" xlink:label="lab_us-gaap_ShareRepurchaseProgramAxis_728F4C6FB845EBEED3E10748377BAFDC" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Share Repurchase Program [Axis]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ShareRepurchaseProgramAxis" xlink:label="loc_us-gaap_ShareRepurchaseProgramAxis_728F4C6FB845EBEED3E10748377BAFDC" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ShareRepurchaseProgramAxis_728F4C6FB845EBEED3E10748377BAFDC" xlink:to="lab_us-gaap_ShareRepurchaseProgramAxis_728F4C6FB845EBEED3E10748377BAFDC" xlink:type="arc" />
    <link:label id="lab_us-gaap_ShareRepurchaseProgramDomain_7DF9A3EBE595A8B05BA60748C1E6213E_terseLabel_en-US" xlink:label="lab_us-gaap_ShareRepurchaseProgramDomain_7DF9A3EBE595A8B05BA60748C1E6213E" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Share Repurchase Program [Domain]</link:label>
    <link:label id="lab_us-gaap_ShareRepurchaseProgramDomain_7DF9A3EBE595A8B05BA60748C1E6213E_label_en-US" xlink:label="lab_us-gaap_ShareRepurchaseProgramDomain_7DF9A3EBE595A8B05BA60748C1E6213E" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Share Repurchase Program [Domain]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ShareRepurchaseProgramDomain" xlink:label="loc_us-gaap_ShareRepurchaseProgramDomain_7DF9A3EBE595A8B05BA60748C1E6213E" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ShareRepurchaseProgramDomain_7DF9A3EBE595A8B05BA60748C1E6213E" xlink:to="lab_us-gaap_ShareRepurchaseProgramDomain_7DF9A3EBE595A8B05BA60748C1E6213E" xlink:type="arc" />
    <link:label id="lab_arnc_AcceleratedShareRepurchaseProgramMember_2853A1F5B4F0FD229C100749698E8A19_terseLabel_en-US" xlink:label="lab_arnc_AcceleratedShareRepurchaseProgramMember_2853A1F5B4F0FD229C100749698E8A19" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Accelerated Share Repurchase Program</link:label>
    <link:label id="lab_arnc_AcceleratedShareRepurchaseProgramMember_2853A1F5B4F0FD229C100749698E8A19_label_en-US" xlink:label="lab_arnc_AcceleratedShareRepurchaseProgramMember_2853A1F5B4F0FD229C100749698E8A19" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Accelerated Share Repurchase Program [Member]</link:label>
    <link:label id="lab_arnc_AcceleratedShareRepurchaseProgramMember_2853A1F5B4F0FD229C100749698E8A19_documentation_en-US" xlink:label="lab_arnc_AcceleratedShareRepurchaseProgramMember_2853A1F5B4F0FD229C100749698E8A19" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Accelerated Share Repurchase Program [Member]</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_AcceleratedShareRepurchaseProgramMember" xlink:label="loc_arnc_AcceleratedShareRepurchaseProgramMember_2853A1F5B4F0FD229C100749698E8A19" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_AcceleratedShareRepurchaseProgramMember_2853A1F5B4F0FD229C100749698E8A19" xlink:to="lab_arnc_AcceleratedShareRepurchaseProgramMember_2853A1F5B4F0FD229C100749698E8A19" xlink:type="arc" />
    <link:label id="lab_us-gaap_SubsequentEventTypeAxis_3F2D2E5D1E470BE0163E073B4F8429F8_terseLabel_en-US" xlink:label="lab_us-gaap_SubsequentEventTypeAxis_3F2D2E5D1E470BE0163E073B4F8429F8" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Subsequent Event Type [Axis]</link:label>
    <link:label id="lab_us-gaap_SubsequentEventTypeAxis_3F2D2E5D1E470BE0163E073B4F8429F8_label_en-US" xlink:label="lab_us-gaap_SubsequentEventTypeAxis_3F2D2E5D1E470BE0163E073B4F8429F8" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Subsequent Event Type [Axis]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_SubsequentEventTypeAxis" xlink:label="loc_us-gaap_SubsequentEventTypeAxis_3F2D2E5D1E470BE0163E073B4F8429F8" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SubsequentEventTypeAxis_3F2D2E5D1E470BE0163E073B4F8429F8" xlink:to="lab_us-gaap_SubsequentEventTypeAxis_3F2D2E5D1E470BE0163E073B4F8429F8" xlink:type="arc" />
    <link:label id="lab_us-gaap_SubsequentEventTypeDomain_1487BE75143C49163AC5073B4F84A927_terseLabel_en-US" xlink:label="lab_us-gaap_SubsequentEventTypeDomain_1487BE75143C49163AC5073B4F84A927" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Subsequent Event Type [Domain]</link:label>
    <link:label id="lab_us-gaap_SubsequentEventTypeDomain_1487BE75143C49163AC5073B4F84A927_label_en-US" xlink:label="lab_us-gaap_SubsequentEventTypeDomain_1487BE75143C49163AC5073B4F84A927" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Subsequent Event Type [Domain]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_SubsequentEventTypeDomain" xlink:label="loc_us-gaap_SubsequentEventTypeDomain_1487BE75143C49163AC5073B4F84A927" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SubsequentEventTypeDomain_1487BE75143C49163AC5073B4F84A927" xlink:to="lab_us-gaap_SubsequentEventTypeDomain_1487BE75143C49163AC5073B4F84A927" xlink:type="arc" />
    <link:label id="lab_us-gaap_SubsequentEventMember_26AD14DEB6D6934D2A9B073B4F883289_terseLabel_en-US" xlink:label="lab_us-gaap_SubsequentEventMember_26AD14DEB6D6934D2A9B073B4F883289" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Subsequent Event</link:label>
    <link:label id="lab_us-gaap_SubsequentEventMember_26AD14DEB6D6934D2A9B073B4F883289_label_en-US" xlink:label="lab_us-gaap_SubsequentEventMember_26AD14DEB6D6934D2A9B073B4F883289" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Subsequent Event [Member]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_SubsequentEventMember" xlink:label="loc_us-gaap_SubsequentEventMember_26AD14DEB6D6934D2A9B073B4F883289" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SubsequentEventMember_26AD14DEB6D6934D2A9B073B4F883289" xlink:to="lab_us-gaap_SubsequentEventMember_26AD14DEB6D6934D2A9B073B4F883289" xlink:type="arc" />
    <link:label id="lab_us-gaap_SubsequentEventLineItems_0835F44811418B87318F073B4F88B581_terseLabel_en-US" xlink:label="lab_us-gaap_SubsequentEventLineItems_0835F44811418B87318F073B4F88B581" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Subsequent Event [Line Items]</link:label>
    <link:label id="lab_us-gaap_SubsequentEventLineItems_0835F44811418B87318F073B4F88B581_label_en-US" xlink:label="lab_us-gaap_SubsequentEventLineItems_0835F44811418B87318F073B4F88B581" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Subsequent Event [Line Items]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_SubsequentEventLineItems" xlink:label="loc_us-gaap_SubsequentEventLineItems_0835F44811418B87318F073B4F88B581" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SubsequentEventLineItems_0835F44811418B87318F073B4F88B581" xlink:to="lab_us-gaap_SubsequentEventLineItems_0835F44811418B87318F073B4F88B581" xlink:type="arc" />
    <link:label id="lab_us-gaap_StockRepurchaseProgramAuthorizedAmount1_3448DDD859C01CE2F66F073B4F88053B_terseLabel_en-US" xlink:label="lab_us-gaap_StockRepurchaseProgramAuthorizedAmount1_3448DDD859C01CE2F66F073B4F88053B" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Stock repurchase program, authorized amount</link:label>
    <link:label id="lab_us-gaap_StockRepurchaseProgramAuthorizedAmount1_3448DDD859C01CE2F66F073B4F88053B_label_en-US" xlink:label="lab_us-gaap_StockRepurchaseProgramAuthorizedAmount1_3448DDD859C01CE2F66F073B4F88053B" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Stock Repurchase Program, Authorized Amount</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_StockRepurchaseProgramAuthorizedAmount1" xlink:label="loc_us-gaap_StockRepurchaseProgramAuthorizedAmount1_3448DDD859C01CE2F66F073B4F88053B" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_StockRepurchaseProgramAuthorizedAmount1_3448DDD859C01CE2F66F073B4F88053B" xlink:to="lab_us-gaap_StockRepurchaseProgramAuthorizedAmount1_3448DDD859C01CE2F66F073B4F88053B" xlink:type="arc" />
    <link:label id="lab_arnc_StockRepurchaseProgramAdditionalSharesAuthorized_6FC1A7E5F29E22DD6053073F28F3E655_terseLabel_en-US" xlink:label="lab_arnc_StockRepurchaseProgramAdditionalSharesAuthorized_6FC1A7E5F29E22DD6053073F28F3E655" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Stock repurchase program, additional amount authorized</link:label>
    <link:label id="lab_arnc_StockRepurchaseProgramAdditionalSharesAuthorized_6FC1A7E5F29E22DD6053073F28F3E655_label_en-US" xlink:label="lab_arnc_StockRepurchaseProgramAdditionalSharesAuthorized_6FC1A7E5F29E22DD6053073F28F3E655" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Stock Repurchase Program, Additional Shares Authorized</link:label>
    <link:label id="lab_arnc_StockRepurchaseProgramAdditionalSharesAuthorized_6FC1A7E5F29E22DD6053073F28F3E655_documentation_en-US" xlink:label="lab_arnc_StockRepurchaseProgramAdditionalSharesAuthorized_6FC1A7E5F29E22DD6053073F28F3E655" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Stock Repurchase Program, Additional Shares Authorized</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_StockRepurchaseProgramAdditionalSharesAuthorized" xlink:label="loc_arnc_StockRepurchaseProgramAdditionalSharesAuthorized_6FC1A7E5F29E22DD6053073F28F3E655" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_StockRepurchaseProgramAdditionalSharesAuthorized_6FC1A7E5F29E22DD6053073F28F3E655" xlink:to="lab_arnc_StockRepurchaseProgramAdditionalSharesAuthorized_6FC1A7E5F29E22DD6053073F28F3E655" xlink:type="arc" />
    <link:label id="lab_arnc_DividendsPayablePlannedDecrease_2C86638B573504965C4B074199C4CEA6_terseLabel_en-US" xlink:label="lab_arnc_DividendsPayablePlannedDecrease_2C86638B573504965C4B074199C4CEA6" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Dividends payable, planned decrease (USD per share)</link:label>
    <link:label id="lab_arnc_DividendsPayablePlannedDecrease_2C86638B573504965C4B074199C4CEA6_label_en-US" xlink:label="lab_arnc_DividendsPayablePlannedDecrease_2C86638B573504965C4B074199C4CEA6" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Dividends Payable, Planned Decrease</link:label>
    <link:label id="lab_arnc_DividendsPayablePlannedDecrease_2C86638B573504965C4B074199C4CEA6_documentation_en-US" xlink:label="lab_arnc_DividendsPayablePlannedDecrease_2C86638B573504965C4B074199C4CEA6" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Dividends Payable, Planned Decrease</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_DividendsPayablePlannedDecrease" xlink:label="loc_arnc_DividendsPayablePlannedDecrease_2C86638B573504965C4B074199C4CEA6" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_DividendsPayablePlannedDecrease_2C86638B573504965C4B074199C4CEA6" xlink:to="lab_arnc_DividendsPayablePlannedDecrease_2C86638B573504965C4B074199C4CEA6" xlink:type="arc" />
    <link:label id="lab_arnc_AcceleratedShareRepurchaseInitialSharesReceived_DEC26C1E29174D0AFC4E07516C34A190_terseLabel_en-US" xlink:label="lab_arnc_AcceleratedShareRepurchaseInitialSharesReceived_DEC26C1E29174D0AFC4E07516C34A190" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Initial number of shares received</link:label>
    <link:label id="lab_arnc_AcceleratedShareRepurchaseInitialSharesReceived_DEC26C1E29174D0AFC4E07516C34A190_label_en-US" xlink:label="lab_arnc_AcceleratedShareRepurchaseInitialSharesReceived_DEC26C1E29174D0AFC4E07516C34A190" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Accelerated Share Repurchase, Initial Shares Received</link:label>
    <link:label id="lab_arnc_AcceleratedShareRepurchaseInitialSharesReceived_DEC26C1E29174D0AFC4E07516C34A190_documentation_en-US" xlink:label="lab_arnc_AcceleratedShareRepurchaseInitialSharesReceived_DEC26C1E29174D0AFC4E07516C34A190" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Accelerated Share Repurchase, Initial Shares Received</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_AcceleratedShareRepurchaseInitialSharesReceived" xlink:label="loc_arnc_AcceleratedShareRepurchaseInitialSharesReceived_DEC26C1E29174D0AFC4E07516C34A190" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_AcceleratedShareRepurchaseInitialSharesReceived_DEC26C1E29174D0AFC4E07516C34A190" xlink:to="lab_arnc_AcceleratedShareRepurchaseInitialSharesReceived_DEC26C1E29174D0AFC4E07516C34A190" xlink:type="arc" />
    <link:label id="lab_us-gaap_CurrentIncomeTaxExpenseBenefitContinuingOperationsAbstract_8E3644F7AA8F663ED7FABB634343A39F_terseLabel_en-US" xlink:label="lab_us-gaap_CurrentIncomeTaxExpenseBenefitContinuingOperationsAbstract_8E3644F7AA8F663ED7FABB634343A39F" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Current:</link:label>
    <link:label id="lab_us-gaap_CurrentIncomeTaxExpenseBenefitContinuingOperationsAbstract_8E3644F7AA8F663ED7FABB634343A39F_label_en-US" xlink:label="lab_us-gaap_CurrentIncomeTaxExpenseBenefitContinuingOperationsAbstract_8E3644F7AA8F663ED7FABB634343A39F" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Current Income Tax Expense (Benefit), Continuing Operations [Abstract]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_CurrentIncomeTaxExpenseBenefitContinuingOperationsAbstract" xlink:label="loc_us-gaap_CurrentIncomeTaxExpenseBenefitContinuingOperationsAbstract_8E3644F7AA8F663ED7FABB634343A39F" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CurrentIncomeTaxExpenseBenefitContinuingOperationsAbstract_8E3644F7AA8F663ED7FABB634343A39F" xlink:to="lab_us-gaap_CurrentIncomeTaxExpenseBenefitContinuingOperationsAbstract_8E3644F7AA8F663ED7FABB634343A39F" xlink:type="arc" />
    <link:label id="lab_us-gaap_CurrentFederalTaxExpenseBenefit_8653A4BE146371D649F1BB63434318A9_terseLabel_en-US" xlink:label="lab_us-gaap_CurrentFederalTaxExpenseBenefit_8653A4BE146371D649F1BB63434318A9" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Federal</link:label>
    <link:label id="lab_us-gaap_CurrentFederalTaxExpenseBenefit_8653A4BE146371D649F1BB63434318A9_label_en-US" xlink:label="lab_us-gaap_CurrentFederalTaxExpenseBenefit_8653A4BE146371D649F1BB63434318A9" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Current Federal Tax Expense (Benefit)</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_CurrentFederalTaxExpenseBenefit" xlink:label="loc_us-gaap_CurrentFederalTaxExpenseBenefit_8653A4BE146371D649F1BB63434318A9" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CurrentFederalTaxExpenseBenefit_8653A4BE146371D649F1BB63434318A9" xlink:to="lab_us-gaap_CurrentFederalTaxExpenseBenefit_8653A4BE146371D649F1BB63434318A9" xlink:type="arc" />
    <link:label id="lab_us-gaap_CurrentForeignTaxExpenseBenefit_169C47404485F9097423BB6343439894_terseLabel_en-US" xlink:label="lab_us-gaap_CurrentForeignTaxExpenseBenefit_169C47404485F9097423BB6343439894" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Foreign</link:label>
    <link:label id="lab_us-gaap_CurrentForeignTaxExpenseBenefit_169C47404485F9097423BB6343439894_label_en-US" xlink:label="lab_us-gaap_CurrentForeignTaxExpenseBenefit_169C47404485F9097423BB6343439894" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Current Foreign Tax Expense (Benefit)</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_CurrentForeignTaxExpenseBenefit" xlink:label="loc_us-gaap_CurrentForeignTaxExpenseBenefit_169C47404485F9097423BB6343439894" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CurrentForeignTaxExpenseBenefit_169C47404485F9097423BB6343439894" xlink:to="lab_us-gaap_CurrentForeignTaxExpenseBenefit_169C47404485F9097423BB6343439894" xlink:type="arc" />
    <link:label id="lab_us-gaap_CurrentStateAndLocalTaxExpenseBenefit_2152D129ADA12DEB8A6BBB63434333EF_terseLabel_en-US" xlink:label="lab_us-gaap_CurrentStateAndLocalTaxExpenseBenefit_2152D129ADA12DEB8A6BBB63434333EF" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">State and local</link:label>
    <link:label id="lab_us-gaap_CurrentStateAndLocalTaxExpenseBenefit_2152D129ADA12DEB8A6BBB63434333EF_label_en-US" xlink:label="lab_us-gaap_CurrentStateAndLocalTaxExpenseBenefit_2152D129ADA12DEB8A6BBB63434333EF" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Current State and Local Tax Expense (Benefit)</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_CurrentStateAndLocalTaxExpenseBenefit" xlink:label="loc_us-gaap_CurrentStateAndLocalTaxExpenseBenefit_2152D129ADA12DEB8A6BBB63434333EF" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CurrentStateAndLocalTaxExpenseBenefit_2152D129ADA12DEB8A6BBB63434333EF" xlink:to="lab_us-gaap_CurrentStateAndLocalTaxExpenseBenefit_2152D129ADA12DEB8A6BBB63434333EF" xlink:type="arc" />
    <link:label id="lab_us-gaap_CurrentIncomeTaxExpenseBenefit_8910963ED8DAF671C213BB63434360C4_totalLabel_en-US" xlink:label="lab_us-gaap_CurrentIncomeTaxExpenseBenefit_8910963ED8DAF671C213BB63434360C4" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Current provision for income taxes, total</link:label>
    <link:label id="lab_us-gaap_CurrentIncomeTaxExpenseBenefit_8910963ED8DAF671C213BB63434360C4_label_en-US" xlink:label="lab_us-gaap_CurrentIncomeTaxExpenseBenefit_8910963ED8DAF671C213BB63434360C4" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Current Income Tax Expense (Benefit)</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_CurrentIncomeTaxExpenseBenefit" xlink:label="loc_us-gaap_CurrentIncomeTaxExpenseBenefit_8910963ED8DAF671C213BB63434360C4" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CurrentIncomeTaxExpenseBenefit_8910963ED8DAF671C213BB63434360C4" xlink:to="lab_us-gaap_CurrentIncomeTaxExpenseBenefit_8910963ED8DAF671C213BB63434360C4" xlink:type="arc" />
    <link:label id="lab_us-gaap_DeferredIncomeTaxExpenseBenefitContinuingOperationsAbstract_423077F7FAC196F5E0D4BB6343474E7B_terseLabel_en-US" xlink:label="lab_us-gaap_DeferredIncomeTaxExpenseBenefitContinuingOperationsAbstract_423077F7FAC196F5E0D4BB6343474E7B" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Deferred:</link:label>
    <link:label id="lab_us-gaap_DeferredIncomeTaxExpenseBenefitContinuingOperationsAbstract_423077F7FAC196F5E0D4BB6343474E7B_label_en-US" xlink:label="lab_us-gaap_DeferredIncomeTaxExpenseBenefitContinuingOperationsAbstract_423077F7FAC196F5E0D4BB6343474E7B" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Deferred Income Tax Expense (Benefit), Continuing Operations [Abstract]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DeferredIncomeTaxExpenseBenefitContinuingOperationsAbstract" xlink:label="loc_us-gaap_DeferredIncomeTaxExpenseBenefitContinuingOperationsAbstract_423077F7FAC196F5E0D4BB6343474E7B" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DeferredIncomeTaxExpenseBenefitContinuingOperationsAbstract_423077F7FAC196F5E0D4BB6343474E7B" xlink:to="lab_us-gaap_DeferredIncomeTaxExpenseBenefitContinuingOperationsAbstract_423077F7FAC196F5E0D4BB6343474E7B" xlink:type="arc" />
    <link:label id="lab_us-gaap_DeferredFederalIncomeTaxExpenseBenefit_836E1D8BF53E9C3E12F8BB63434740E7_terseLabel_en-US" xlink:label="lab_us-gaap_DeferredFederalIncomeTaxExpenseBenefit_836E1D8BF53E9C3E12F8BB63434740E7" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Federal</link:label>
    <link:label id="lab_us-gaap_DeferredFederalIncomeTaxExpenseBenefit_836E1D8BF53E9C3E12F8BB63434740E7_label_en-US" xlink:label="lab_us-gaap_DeferredFederalIncomeTaxExpenseBenefit_836E1D8BF53E9C3E12F8BB63434740E7" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Deferred Federal Income Tax Expense (Benefit)</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DeferredFederalIncomeTaxExpenseBenefit" xlink:label="loc_us-gaap_DeferredFederalIncomeTaxExpenseBenefit_836E1D8BF53E9C3E12F8BB63434740E7" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DeferredFederalIncomeTaxExpenseBenefit_836E1D8BF53E9C3E12F8BB63434740E7" xlink:to="lab_us-gaap_DeferredFederalIncomeTaxExpenseBenefit_836E1D8BF53E9C3E12F8BB63434740E7" xlink:type="arc" />
    <link:label id="lab_us-gaap_DeferredForeignIncomeTaxExpenseBenefit_7D5DB4A8E07A879D5A43BB63434751BA_terseLabel_en-US" xlink:label="lab_us-gaap_DeferredForeignIncomeTaxExpenseBenefit_7D5DB4A8E07A879D5A43BB63434751BA" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Foreign</link:label>
    <link:label id="lab_us-gaap_DeferredForeignIncomeTaxExpenseBenefit_7D5DB4A8E07A879D5A43BB63434751BA_label_en-US" xlink:label="lab_us-gaap_DeferredForeignIncomeTaxExpenseBenefit_7D5DB4A8E07A879D5A43BB63434751BA" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Deferred Foreign Income Tax Expense (Benefit)</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DeferredForeignIncomeTaxExpenseBenefit" xlink:label="loc_us-gaap_DeferredForeignIncomeTaxExpenseBenefit_7D5DB4A8E07A879D5A43BB63434751BA" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DeferredForeignIncomeTaxExpenseBenefit_7D5DB4A8E07A879D5A43BB63434751BA" xlink:to="lab_us-gaap_DeferredForeignIncomeTaxExpenseBenefit_7D5DB4A8E07A879D5A43BB63434751BA" xlink:type="arc" />
    <link:label id="lab_us-gaap_DeferredStateAndLocalIncomeTaxExpenseBenefit_DD58ACA86B7F26D8EE97BB6343473F9B_terseLabel_en-US" xlink:label="lab_us-gaap_DeferredStateAndLocalIncomeTaxExpenseBenefit_DD58ACA86B7F26D8EE97BB6343473F9B" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">State and local</link:label>
    <link:label id="lab_us-gaap_DeferredStateAndLocalIncomeTaxExpenseBenefit_DD58ACA86B7F26D8EE97BB6343473F9B_label_en-US" xlink:label="lab_us-gaap_DeferredStateAndLocalIncomeTaxExpenseBenefit_DD58ACA86B7F26D8EE97BB6343473F9B" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Deferred State and Local Income Tax Expense (Benefit)</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DeferredStateAndLocalIncomeTaxExpenseBenefit" xlink:label="loc_us-gaap_DeferredStateAndLocalIncomeTaxExpenseBenefit_DD58ACA86B7F26D8EE97BB6343473F9B" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DeferredStateAndLocalIncomeTaxExpenseBenefit_DD58ACA86B7F26D8EE97BB6343473F9B" xlink:to="lab_us-gaap_DeferredStateAndLocalIncomeTaxExpenseBenefit_DD58ACA86B7F26D8EE97BB6343473F9B" xlink:type="arc" />
    <link:label id="lab_us-gaap_DeferredIncomeTaxExpenseBenefit_88F4F4AAFDCAC0365B63BB634347A944_totalLabel_en-US" xlink:label="lab_us-gaap_DeferredIncomeTaxExpenseBenefit_88F4F4AAFDCAC0365B63BB634347A944" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Deferred provision for income taxes, total</link:label>
    <link:label id="lab_us-gaap_DeferredIncomeTaxExpenseBenefit_88F4F4AAFDCAC0365B63BB634347A944_label_en-US" xlink:label="lab_us-gaap_DeferredIncomeTaxExpenseBenefit_88F4F4AAFDCAC0365B63BB634347A944" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Deferred Income Tax Expense (Benefit)</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DeferredIncomeTaxExpenseBenefit" xlink:label="loc_us-gaap_DeferredIncomeTaxExpenseBenefit_88F4F4AAFDCAC0365B63BB634347A944" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DeferredIncomeTaxExpenseBenefit_88F4F4AAFDCAC0365B63BB634347A944" xlink:to="lab_us-gaap_DeferredIncomeTaxExpenseBenefit_88F4F4AAFDCAC0365B63BB634347A944" xlink:type="arc" />
    <link:label id="lab_us-gaap_IncomeTaxExpenseBenefit_5DC0CAF96008E669142BBB6343470821_totalLabel_en-US" xlink:label="lab_us-gaap_IncomeTaxExpenseBenefit_5DC0CAF96008E669142BBB6343470821" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Total</link:label>
    <link:label id="lab_us-gaap_IncomeTaxExpenseBenefit_5DC0CAF96008E669142BBB6343470821_label_en-US" xlink:label="lab_us-gaap_IncomeTaxExpenseBenefit_5DC0CAF96008E669142BBB6343470821" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Income Tax Expense (Benefit)</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_IncomeTaxExpenseBenefit" xlink:label="loc_us-gaap_IncomeTaxExpenseBenefit_5DC0CAF96008E669142BBB6343470821" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncomeTaxExpenseBenefit_5DC0CAF96008E669142BBB6343470821" xlink:to="lab_us-gaap_IncomeTaxExpenseBenefit_5DC0CAF96008E669142BBB6343470821" xlink:type="arc" />
    <link:label id="lab_us-gaap_DebtInstrumentTable_49370895DA24303763D5E2A5AA8E9854_terseLabel_en-US" xlink:label="lab_us-gaap_DebtInstrumentTable_49370895DA24303763D5E2A5AA8E9854" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Schedule of Long-term Debt Instruments [Table]</link:label>
    <link:label id="lab_us-gaap_DebtInstrumentTable_49370895DA24303763D5E2A5AA8E9854_label_en-US" xlink:label="lab_us-gaap_DebtInstrumentTable_49370895DA24303763D5E2A5AA8E9854" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Schedule of Long-term Debt Instruments [Table]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DebtInstrumentTable" xlink:label="loc_us-gaap_DebtInstrumentTable_49370895DA24303763D5E2A5AA8E9854" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DebtInstrumentTable_49370895DA24303763D5E2A5AA8E9854" xlink:to="lab_us-gaap_DebtInstrumentTable_49370895DA24303763D5E2A5AA8E9854" xlink:type="arc" />
    <link:label id="lab_us-gaap_LongtermDebtTypeAxis_27BEEA0ECC0C5DB39C98E2A5AA8F15D5_terseLabel_en-US" xlink:label="lab_us-gaap_LongtermDebtTypeAxis_27BEEA0ECC0C5DB39C98E2A5AA8F15D5" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Long-term Debt, Type [Axis]</link:label>
    <link:label id="lab_us-gaap_LongtermDebtTypeAxis_27BEEA0ECC0C5DB39C98E2A5AA8F15D5_label_en-US" xlink:label="lab_us-gaap_LongtermDebtTypeAxis_27BEEA0ECC0C5DB39C98E2A5AA8F15D5" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Long-term Debt, Type [Axis]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_LongtermDebtTypeAxis" xlink:label="loc_us-gaap_LongtermDebtTypeAxis_27BEEA0ECC0C5DB39C98E2A5AA8F15D5" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_27BEEA0ECC0C5DB39C98E2A5AA8F15D5" xlink:to="lab_us-gaap_LongtermDebtTypeAxis_27BEEA0ECC0C5DB39C98E2A5AA8F15D5" xlink:type="arc" />
    <link:label id="lab_us-gaap_LongtermDebtTypeDomain_9DA32D1D0C8531E066D4E2A5AA8F9844_terseLabel_en-US" xlink:label="lab_us-gaap_LongtermDebtTypeDomain_9DA32D1D0C8531E066D4E2A5AA8F9844" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Long-term Debt, Type [Domain]</link:label>
    <link:label id="lab_us-gaap_LongtermDebtTypeDomain_9DA32D1D0C8531E066D4E2A5AA8F9844_label_en-US" xlink:label="lab_us-gaap_LongtermDebtTypeDomain_9DA32D1D0C8531E066D4E2A5AA8F9844" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Long-term Debt, Type [Domain]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_LongtermDebtTypeDomain" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_9DA32D1D0C8531E066D4E2A5AA8F9844" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_9DA32D1D0C8531E066D4E2A5AA8F9844" xlink:to="lab_us-gaap_LongtermDebtTypeDomain_9DA32D1D0C8531E066D4E2A5AA8F9844" xlink:type="arc" />
    <link:label id="lab_arnc_RevolvingCreditAgreementMember_C168FAFD8CD6CCA5EC28E2A5AA8FC661_terseLabel_en-US" xlink:label="lab_arnc_RevolvingCreditAgreementMember_C168FAFD8CD6CCA5EC28E2A5AA8FC661" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Revolving Credit Agreement</link:label>
    <link:label id="lab_arnc_RevolvingCreditAgreementMember_C168FAFD8CD6CCA5EC28E2A5AA8FC661_label_en-US" xlink:label="lab_arnc_RevolvingCreditAgreementMember_C168FAFD8CD6CCA5EC28E2A5AA8FC661" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Revolving Credit Agreement [Member]</link:label>
    <link:label id="lab_arnc_RevolvingCreditAgreementMember_C168FAFD8CD6CCA5EC28E2A5AA8FC661_documentation_en-US" xlink:label="lab_arnc_RevolvingCreditAgreementMember_C168FAFD8CD6CCA5EC28E2A5AA8FC661" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Revolving credit agreement.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_RevolvingCreditAgreementMember" xlink:label="loc_arnc_RevolvingCreditAgreementMember_C168FAFD8CD6CCA5EC28E2A5AA8FC661" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_RevolvingCreditAgreementMember_C168FAFD8CD6CCA5EC28E2A5AA8FC661" xlink:to="lab_arnc_RevolvingCreditAgreementMember_C168FAFD8CD6CCA5EC28E2A5AA8FC661" xlink:type="arc" />
    <link:label id="lab_arnc_SeniorUnsecuredRevolvingCreditFacilityMember_F2720A4181E94294D5DFE2A5AA90E4B5_terseLabel_en-US" xlink:label="lab_arnc_SeniorUnsecuredRevolvingCreditFacilityMember_F2720A4181E94294D5DFE2A5AA90E4B5" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Senior Unsecured Revolving Credit Facility</link:label>
    <link:label id="lab_arnc_SeniorUnsecuredRevolvingCreditFacilityMember_F2720A4181E94294D5DFE2A5AA90E4B5_label_en-US" xlink:label="lab_arnc_SeniorUnsecuredRevolvingCreditFacilityMember_F2720A4181E94294D5DFE2A5AA90E4B5" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Senior Unsecured Revolving Credit Facility [Member]</link:label>
    <link:label id="lab_arnc_SeniorUnsecuredRevolvingCreditFacilityMember_F2720A4181E94294D5DFE2A5AA90E4B5_documentation_en-US" xlink:label="lab_arnc_SeniorUnsecuredRevolvingCreditFacilityMember_F2720A4181E94294D5DFE2A5AA90E4B5" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Senior Unsecured Revolving Credit Facility [Member]</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_SeniorUnsecuredRevolvingCreditFacilityMember" xlink:label="loc_arnc_SeniorUnsecuredRevolvingCreditFacilityMember_F2720A4181E94294D5DFE2A5AA90E4B5" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_SeniorUnsecuredRevolvingCreditFacilityMember_F2720A4181E94294D5DFE2A5AA90E4B5" xlink:to="lab_arnc_SeniorUnsecuredRevolvingCreditFacilityMember_F2720A4181E94294D5DFE2A5AA90E4B5" xlink:type="arc" />
    <link:label id="lab_arnc_ExpectedMaturityDateYear2019Member_2F90B3B28B6E9FC34AFFE2A5AA90645A_terseLabel_en-US" xlink:label="lab_arnc_ExpectedMaturityDateYear2019Member_2F90B3B28B6E9FC34AFFE2A5AA90645A" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Expected Maturity Date Year 2019</link:label>
    <link:label id="lab_arnc_ExpectedMaturityDateYear2019Member_2F90B3B28B6E9FC34AFFE2A5AA90645A_label_en-US" xlink:label="lab_arnc_ExpectedMaturityDateYear2019Member_2F90B3B28B6E9FC34AFFE2A5AA90645A" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Expected Maturity Date Year 2019 [Member]</link:label>
    <link:label id="lab_arnc_ExpectedMaturityDateYear2019Member_2F90B3B28B6E9FC34AFFE2A5AA90645A_documentation_en-US" xlink:label="lab_arnc_ExpectedMaturityDateYear2019Member_2F90B3B28B6E9FC34AFFE2A5AA90645A" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Expected Maturity Date Year 2019 [Member]</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_ExpectedMaturityDateYear2019Member" xlink:label="loc_arnc_ExpectedMaturityDateYear2019Member_2F90B3B28B6E9FC34AFFE2A5AA90645A" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_ExpectedMaturityDateYear2019Member_2F90B3B28B6E9FC34AFFE2A5AA90645A" xlink:to="lab_arnc_ExpectedMaturityDateYear2019Member_2F90B3B28B6E9FC34AFFE2A5AA90645A" xlink:type="arc" />
    <link:label id="lab_arnc_ExpectedMaturityDateYear2020Member_2D398CDDF7E455CC7C97E2A5AA901FEC_terseLabel_en-US" xlink:label="lab_arnc_ExpectedMaturityDateYear2020Member_2D398CDDF7E455CC7C97E2A5AA901FEC" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Expected Maturity Date Year 2020</link:label>
    <link:label id="lab_arnc_ExpectedMaturityDateYear2020Member_2D398CDDF7E455CC7C97E2A5AA901FEC_label_en-US" xlink:label="lab_arnc_ExpectedMaturityDateYear2020Member_2D398CDDF7E455CC7C97E2A5AA901FEC" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Expected Maturity Date Year 2020 [Member]</link:label>
    <link:label id="lab_arnc_ExpectedMaturityDateYear2020Member_2D398CDDF7E455CC7C97E2A5AA901FEC_documentation_en-US" xlink:label="lab_arnc_ExpectedMaturityDateYear2020Member_2D398CDDF7E455CC7C97E2A5AA901FEC" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Expected Maturity Date Year 2020 [Member]</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_ExpectedMaturityDateYear2020Member" xlink:label="loc_arnc_ExpectedMaturityDateYear2020Member_2D398CDDF7E455CC7C97E2A5AA901FEC" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_ExpectedMaturityDateYear2020Member_2D398CDDF7E455CC7C97E2A5AA901FEC" xlink:to="lab_arnc_ExpectedMaturityDateYear2020Member_2D398CDDF7E455CC7C97E2A5AA901FEC" xlink:type="arc" />
    <link:label id="lab_us-gaap_CreditFacilityAxis_62712447CB146445B3A2E2A5AA90983F_terseLabel_en-US" xlink:label="lab_us-gaap_CreditFacilityAxis_62712447CB146445B3A2E2A5AA90983F" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Credit Facility [Axis]</link:label>
    <link:label id="lab_us-gaap_CreditFacilityAxis_62712447CB146445B3A2E2A5AA90983F_label_en-US" xlink:label="lab_us-gaap_CreditFacilityAxis_62712447CB146445B3A2E2A5AA90983F" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Credit Facility [Axis]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_CreditFacilityAxis" xlink:label="loc_us-gaap_CreditFacilityAxis_62712447CB146445B3A2E2A5AA90983F" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CreditFacilityAxis_62712447CB146445B3A2E2A5AA90983F" xlink:to="lab_us-gaap_CreditFacilityAxis_62712447CB146445B3A2E2A5AA90983F" xlink:type="arc" />
    <link:label id="lab_us-gaap_CreditFacilityDomain_B83E6700D466A961EE63E2A5AA9013CA_terseLabel_en-US" xlink:label="lab_us-gaap_CreditFacilityDomain_B83E6700D466A961EE63E2A5AA9013CA" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Credit Facility [Domain]</link:label>
    <link:label id="lab_us-gaap_CreditFacilityDomain_B83E6700D466A961EE63E2A5AA9013CA_label_en-US" xlink:label="lab_us-gaap_CreditFacilityDomain_B83E6700D466A961EE63E2A5AA9013CA" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Credit Facility [Domain]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_CreditFacilityDomain" xlink:label="loc_us-gaap_CreditFacilityDomain_B83E6700D466A961EE63E2A5AA9013CA" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CreditFacilityDomain_B83E6700D466A961EE63E2A5AA9013CA" xlink:to="lab_us-gaap_CreditFacilityDomain_B83E6700D466A961EE63E2A5AA9013CA" xlink:type="arc" />
    <link:label id="lab_us-gaap_LetterOfCreditMember_3399971111C5A6EE4C81E2A5AA91754F_terseLabel_en-US" xlink:label="lab_us-gaap_LetterOfCreditMember_3399971111C5A6EE4C81E2A5AA91754F" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Letter of Credit</link:label>
    <link:label id="lab_us-gaap_LetterOfCreditMember_3399971111C5A6EE4C81E2A5AA91754F_label_en-US" xlink:label="lab_us-gaap_LetterOfCreditMember_3399971111C5A6EE4C81E2A5AA91754F" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Letter of Credit [Member]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_LetterOfCreditMember" xlink:label="loc_us-gaap_LetterOfCreditMember_3399971111C5A6EE4C81E2A5AA91754F" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LetterOfCreditMember_3399971111C5A6EE4C81E2A5AA91754F" xlink:to="lab_us-gaap_LetterOfCreditMember_3399971111C5A6EE4C81E2A5AA91754F" xlink:type="arc" />
    <link:label id="lab_us-gaap_LoanRestructuringModificationAxis_F04FEAFC67832A604CC9E2A5AA92F3C7_terseLabel_en-US" xlink:label="lab_us-gaap_LoanRestructuringModificationAxis_F04FEAFC67832A604CC9E2A5AA92F3C7" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Loan Restructuring Modification [Axis]</link:label>
    <link:label id="lab_us-gaap_LoanRestructuringModificationAxis_F04FEAFC67832A604CC9E2A5AA92F3C7_label_en-US" xlink:label="lab_us-gaap_LoanRestructuringModificationAxis_F04FEAFC67832A604CC9E2A5AA92F3C7" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Loan Restructuring Modification [Axis]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_LoanRestructuringModificationAxis" xlink:label="loc_us-gaap_LoanRestructuringModificationAxis_F04FEAFC67832A604CC9E2A5AA92F3C7" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LoanRestructuringModificationAxis_F04FEAFC67832A604CC9E2A5AA92F3C7" xlink:to="lab_us-gaap_LoanRestructuringModificationAxis_F04FEAFC67832A604CC9E2A5AA92F3C7" xlink:type="arc" />
    <link:label id="lab_us-gaap_LoanRestructuringModificationDomain_BA5E746342D16CAB7EC5E2A5AA925969_terseLabel_en-US" xlink:label="lab_us-gaap_LoanRestructuringModificationDomain_BA5E746342D16CAB7EC5E2A5AA925969" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Loan Restructuring Modification [Domain]</link:label>
    <link:label id="lab_us-gaap_LoanRestructuringModificationDomain_BA5E746342D16CAB7EC5E2A5AA925969_label_en-US" xlink:label="lab_us-gaap_LoanRestructuringModificationDomain_BA5E746342D16CAB7EC5E2A5AA925969" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Loan Restructuring Modification [Domain]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_LoanRestructuringModificationDomain" xlink:label="loc_us-gaap_LoanRestructuringModificationDomain_BA5E746342D16CAB7EC5E2A5AA925969" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LoanRestructuringModificationDomain_BA5E746342D16CAB7EC5E2A5AA925969" xlink:to="lab_us-gaap_LoanRestructuringModificationDomain_BA5E746342D16CAB7EC5E2A5AA925969" xlink:type="arc" />
    <link:label id="lab_arnc_PriorToAmendmentMember_674F03E428F8B164FA83E2A5AA925862_terseLabel_en-US" xlink:label="lab_arnc_PriorToAmendmentMember_674F03E428F8B164FA83E2A5AA925862" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Prior to Amendment</link:label>
    <link:label id="lab_arnc_PriorToAmendmentMember_674F03E428F8B164FA83E2A5AA925862_label_en-US" xlink:label="lab_arnc_PriorToAmendmentMember_674F03E428F8B164FA83E2A5AA925862" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Prior To Amendment [Member]</link:label>
    <link:label id="lab_arnc_PriorToAmendmentMember_674F03E428F8B164FA83E2A5AA925862_documentation_en-US" xlink:label="lab_arnc_PriorToAmendmentMember_674F03E428F8B164FA83E2A5AA925862" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Prior to amendment.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_PriorToAmendmentMember" xlink:label="loc_arnc_PriorToAmendmentMember_674F03E428F8B164FA83E2A5AA925862" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_PriorToAmendmentMember_674F03E428F8B164FA83E2A5AA925862" xlink:to="lab_arnc_PriorToAmendmentMember_674F03E428F8B164FA83E2A5AA925862" xlink:type="arc" />
    <link:label id="lab_arnc_AfterAmendmentMember_8CB56FBD0577B5098F24E2A5AA925D82_terseLabel_en-US" xlink:label="lab_arnc_AfterAmendmentMember_8CB56FBD0577B5098F24E2A5AA925D82" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">After Amendment</link:label>
    <link:label id="lab_arnc_AfterAmendmentMember_8CB56FBD0577B5098F24E2A5AA925D82_label_en-US" xlink:label="lab_arnc_AfterAmendmentMember_8CB56FBD0577B5098F24E2A5AA925D82" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">After Amendment [Member]</link:label>
    <link:label id="lab_arnc_AfterAmendmentMember_8CB56FBD0577B5098F24E2A5AA925D82_documentation_en-US" xlink:label="lab_arnc_AfterAmendmentMember_8CB56FBD0577B5098F24E2A5AA925D82" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">After amendment.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_AfterAmendmentMember" xlink:label="loc_arnc_AfterAmendmentMember_8CB56FBD0577B5098F24E2A5AA925D82" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_AfterAmendmentMember_8CB56FBD0577B5098F24E2A5AA925D82" xlink:to="lab_arnc_AfterAmendmentMember_8CB56FBD0577B5098F24E2A5AA925D82" xlink:type="arc" />
    <link:label id="lab_srt_ConsolidatedEntitiesAxis_4C7C4783E72B4604EBD3E2A5AA930C71_terseLabel_en-US" xlink:label="lab_srt_ConsolidatedEntitiesAxis_4C7C4783E72B4604EBD3E2A5AA930C71" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Consolidated Entities [Axis]</link:label>
    <link:label id="lab_srt_ConsolidatedEntitiesAxis_4C7C4783E72B4604EBD3E2A5AA930C71_label_en-US" xlink:label="lab_srt_ConsolidatedEntitiesAxis_4C7C4783E72B4604EBD3E2A5AA930C71" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Consolidated Entities [Axis]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_ConsolidatedEntitiesAxis" xlink:label="loc_srt_ConsolidatedEntitiesAxis_4C7C4783E72B4604EBD3E2A5AA930C71" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_srt_ConsolidatedEntitiesAxis_4C7C4783E72B4604EBD3E2A5AA930C71" xlink:to="lab_srt_ConsolidatedEntitiesAxis_4C7C4783E72B4604EBD3E2A5AA930C71" xlink:type="arc" />
    <link:label id="lab_srt_ConsolidatedEntitiesDomain_2EEECEAE93D2A8AB2D25E2A5AA938C19_terseLabel_en-US" xlink:label="lab_srt_ConsolidatedEntitiesDomain_2EEECEAE93D2A8AB2D25E2A5AA938C19" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Consolidated Entities [Domain]</link:label>
    <link:label id="lab_srt_ConsolidatedEntitiesDomain_2EEECEAE93D2A8AB2D25E2A5AA938C19_label_en-US" xlink:label="lab_srt_ConsolidatedEntitiesDomain_2EEECEAE93D2A8AB2D25E2A5AA938C19" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Consolidated Entities [Domain]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_ConsolidatedEntitiesDomain" xlink:label="loc_srt_ConsolidatedEntitiesDomain_2EEECEAE93D2A8AB2D25E2A5AA938C19" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_srt_ConsolidatedEntitiesDomain_2EEECEAE93D2A8AB2D25E2A5AA938C19" xlink:to="lab_srt_ConsolidatedEntitiesDomain_2EEECEAE93D2A8AB2D25E2A5AA938C19" xlink:type="arc" />
    <link:label id="lab_srt_ParentCompanyMember_289586F6B525DD8ABEF7E2A5AA937DC4_terseLabel_en-US" xlink:label="lab_srt_ParentCompanyMember_289586F6B525DD8ABEF7E2A5AA937DC4" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Arconic</link:label>
    <link:label id="lab_srt_ParentCompanyMember_289586F6B525DD8ABEF7E2A5AA937DC4_label_en-US" xlink:label="lab_srt_ParentCompanyMember_289586F6B525DD8ABEF7E2A5AA937DC4" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Parent Company [Member]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_ParentCompanyMember" xlink:label="loc_srt_ParentCompanyMember_289586F6B525DD8ABEF7E2A5AA937DC4" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_srt_ParentCompanyMember_289586F6B525DD8ABEF7E2A5AA937DC4" xlink:to="lab_srt_ParentCompanyMember_289586F6B525DD8ABEF7E2A5AA937DC4" xlink:type="arc" />
    <link:label id="lab_us-gaap_DebtInstrumentLineItems_2543B5045F38AAC76076E2A5AA93B884_terseLabel_en-US" xlink:label="lab_us-gaap_DebtInstrumentLineItems_2543B5045F38AAC76076E2A5AA93B884" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Debt Instrument [Line Items]</link:label>
    <link:label id="lab_us-gaap_DebtInstrumentLineItems_2543B5045F38AAC76076E2A5AA93B884_label_en-US" xlink:label="lab_us-gaap_DebtInstrumentLineItems_2543B5045F38AAC76076E2A5AA93B884" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Debt Instrument [Line Items]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DebtInstrumentLineItems" xlink:label="loc_us-gaap_DebtInstrumentLineItems_2543B5045F38AAC76076E2A5AA93B884" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DebtInstrumentLineItems_2543B5045F38AAC76076E2A5AA93B884" xlink:to="lab_us-gaap_DebtInstrumentLineItems_2543B5045F38AAC76076E2A5AA93B884" xlink:type="arc" />
    <link:label id="lab_arnc_LineOfCreditFacilityTerm_501A15E5A2D93C7B7953E2A5AA935715_terseLabel_en-US" xlink:label="lab_arnc_LineOfCreditFacilityTerm_501A15E5A2D93C7B7953E2A5AA935715" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Revolving credit facility, term</link:label>
    <link:label id="lab_arnc_LineOfCreditFacilityTerm_501A15E5A2D93C7B7953E2A5AA935715_label_en-US" xlink:label="lab_arnc_LineOfCreditFacilityTerm_501A15E5A2D93C7B7953E2A5AA935715" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Line Of Credit Facility Term</link:label>
    <link:label id="lab_arnc_LineOfCreditFacilityTerm_501A15E5A2D93C7B7953E2A5AA935715_documentation_en-US" xlink:label="lab_arnc_LineOfCreditFacilityTerm_501A15E5A2D93C7B7953E2A5AA935715" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Line of credit facility, term.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_LineOfCreditFacilityTerm" xlink:label="loc_arnc_LineOfCreditFacilityTerm_501A15E5A2D93C7B7953E2A5AA935715" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_LineOfCreditFacilityTerm_501A15E5A2D93C7B7953E2A5AA935715" xlink:to="lab_arnc_LineOfCreditFacilityTerm_501A15E5A2D93C7B7953E2A5AA935715" xlink:type="arc" />
    <link:label id="lab_us-gaap_LineOfCredit_C8385E137C3D269C3B73E2A5AA9470BB_terseLabel_en-US" xlink:label="lab_us-gaap_LineOfCredit_C8385E137C3D269C3B73E2A5AA9470BB" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Line of credit facility, outstanding borrowings</link:label>
    <link:label id="lab_us-gaap_LineOfCredit_C8385E137C3D269C3B73E2A5AA9470BB_label_en-US" xlink:label="lab_us-gaap_LineOfCredit_C8385E137C3D269C3B73E2A5AA9470BB" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Long-term Line of Credit</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_LineOfCredit" xlink:label="loc_us-gaap_LineOfCredit_C8385E137C3D269C3B73E2A5AA9470BB" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LineOfCredit_C8385E137C3D269C3B73E2A5AA9470BB" xlink:to="lab_us-gaap_LineOfCredit_C8385E137C3D269C3B73E2A5AA9470BB" xlink:type="arc" />
    <link:label id="lab_arnc_LineofCreditFacilityMaximumIncreaseinBorrowingCapacity_3427133FE4A3139170ACE2A5AA94C843_terseLabel_en-US" xlink:label="lab_arnc_LineofCreditFacilityMaximumIncreaseinBorrowingCapacity_3427133FE4A3139170ACE2A5AA94C843" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Maximum increase in borrowing capacity</link:label>
    <link:label id="lab_arnc_LineofCreditFacilityMaximumIncreaseinBorrowingCapacity_3427133FE4A3139170ACE2A5AA94C843_label_en-US" xlink:label="lab_arnc_LineofCreditFacilityMaximumIncreaseinBorrowingCapacity_3427133FE4A3139170ACE2A5AA94C843" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Line of Credit Facility, Maximum Increase in Borrowing Capacity</link:label>
    <link:label id="lab_arnc_LineofCreditFacilityMaximumIncreaseinBorrowingCapacity_3427133FE4A3139170ACE2A5AA94C843_documentation_en-US" xlink:label="lab_arnc_LineofCreditFacilityMaximumIncreaseinBorrowingCapacity_3427133FE4A3139170ACE2A5AA94C843" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Line of Credit Facility, Maximum Increase in Borrowing Capacity</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_LineofCreditFacilityMaximumIncreaseinBorrowingCapacity" xlink:label="loc_arnc_LineofCreditFacilityMaximumIncreaseinBorrowingCapacity_3427133FE4A3139170ACE2A5AA94C843" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_LineofCreditFacilityMaximumIncreaseinBorrowingCapacity_3427133FE4A3139170ACE2A5AA94C843" xlink:to="lab_arnc_LineofCreditFacilityMaximumIncreaseinBorrowingCapacity_3427133FE4A3139170ACE2A5AA94C843" xlink:type="arc" />
    <link:label id="lab_arnc_DebtCovenantsNetLeverageRatio_D135C8628D5119462A9CE2A5AA9464FC_terseLabel_en-US" xlink:label="lab_arnc_DebtCovenantsNetLeverageRatio_D135C8628D5119462A9CE2A5AA9464FC" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Ratio of indebtedness to consolidated EBITDA</link:label>
    <link:label id="lab_arnc_DebtCovenantsNetLeverageRatio_D135C8628D5119462A9CE2A5AA9464FC_label_en-US" xlink:label="lab_arnc_DebtCovenantsNetLeverageRatio_D135C8628D5119462A9CE2A5AA9464FC" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Debt Covenants Net Leverage Ratio</link:label>
    <link:label id="lab_arnc_DebtCovenantsNetLeverageRatio_D135C8628D5119462A9CE2A5AA9464FC_documentation_en-US" xlink:label="lab_arnc_DebtCovenantsNetLeverageRatio_D135C8628D5119462A9CE2A5AA9464FC" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Debt covenants net leverage ratio.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_DebtCovenantsNetLeverageRatio" xlink:label="loc_arnc_DebtCovenantsNetLeverageRatio_D135C8628D5119462A9CE2A5AA9464FC" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_DebtCovenantsNetLeverageRatio_D135C8628D5119462A9CE2A5AA9464FC" xlink:to="lab_arnc_DebtCovenantsNetLeverageRatio_D135C8628D5119462A9CE2A5AA9464FC" xlink:type="arc" />
    <link:label id="lab_arnc_DebtCovenantsNetLeverageRatioAfterYearThree_0C30A2BB40D108CD2EAAE2A5AA947CE7_terseLabel_en-US" xlink:label="lab_arnc_DebtCovenantsNetLeverageRatioAfterYearThree_0C30A2BB40D108CD2EAAE2A5AA947CE7" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Ratio of indebtedness to consolidated EBITDA, after December 31, 2019</link:label>
    <link:label id="lab_arnc_DebtCovenantsNetLeverageRatioAfterYearThree_0C30A2BB40D108CD2EAAE2A5AA947CE7_label_en-US" xlink:label="lab_arnc_DebtCovenantsNetLeverageRatioAfterYearThree_0C30A2BB40D108CD2EAAE2A5AA947CE7" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Debt Covenants Net Leverage Ratio After Year Three</link:label>
    <link:label id="lab_arnc_DebtCovenantsNetLeverageRatioAfterYearThree_0C30A2BB40D108CD2EAAE2A5AA947CE7_documentation_en-US" xlink:label="lab_arnc_DebtCovenantsNetLeverageRatioAfterYearThree_0C30A2BB40D108CD2EAAE2A5AA947CE7" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Debt covenants net leverage ratio after year three.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_DebtCovenantsNetLeverageRatioAfterYearThree" xlink:label="loc_arnc_DebtCovenantsNetLeverageRatioAfterYearThree_0C30A2BB40D108CD2EAAE2A5AA947CE7" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_DebtCovenantsNetLeverageRatioAfterYearThree_0C30A2BB40D108CD2EAAE2A5AA947CE7" xlink:to="lab_arnc_DebtCovenantsNetLeverageRatioAfterYearThree_0C30A2BB40D108CD2EAAE2A5AA947CE7" xlink:type="arc" />
    <link:label id="lab_arnc_DebtCovenantsNetLeverageRatioAfterYearFour_9532E80351D9E8661109E2A5AA945B9E_terseLabel_en-US" xlink:label="lab_arnc_DebtCovenantsNetLeverageRatioAfterYearFour_9532E80351D9E8661109E2A5AA945B9E" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Consolidated Net Debt to consolidated EBITDA ratio</link:label>
    <link:label id="lab_arnc_DebtCovenantsNetLeverageRatioAfterYearFour_9532E80351D9E8661109E2A5AA945B9E_label_en-US" xlink:label="lab_arnc_DebtCovenantsNetLeverageRatioAfterYearFour_9532E80351D9E8661109E2A5AA945B9E" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Debt Covenants Net Leverage Ratio After Year Four</link:label>
    <link:label id="lab_arnc_DebtCovenantsNetLeverageRatioAfterYearFour_9532E80351D9E8661109E2A5AA945B9E_documentation_en-US" xlink:label="lab_arnc_DebtCovenantsNetLeverageRatioAfterYearFour_9532E80351D9E8661109E2A5AA945B9E" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Debt Covenants Net Leverage Ratio After Year Four</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_DebtCovenantsNetLeverageRatioAfterYearFour" xlink:label="loc_arnc_DebtCovenantsNetLeverageRatioAfterYearFour_9532E80351D9E8661109E2A5AA945B9E" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_DebtCovenantsNetLeverageRatioAfterYearFour_9532E80351D9E8661109E2A5AA945B9E" xlink:to="lab_arnc_DebtCovenantsNetLeverageRatioAfterYearFour_9532E80351D9E8661109E2A5AA945B9E" xlink:type="arc" />
    <link:label id="lab_arnc_DebtInstrumentNumberofExtensions_1BCB696B74155F2F6D72E2A5AA943C1D_terseLabel_en-US" xlink:label="lab_arnc_DebtInstrumentNumberofExtensions_1BCB696B74155F2F6D72E2A5AA943C1D" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Number of extensions allowable under terms of the Credit Facility</link:label>
    <link:label id="lab_arnc_DebtInstrumentNumberofExtensions_1BCB696B74155F2F6D72E2A5AA943C1D_label_en-US" xlink:label="lab_arnc_DebtInstrumentNumberofExtensions_1BCB696B74155F2F6D72E2A5AA943C1D" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Debt Instrument, Number of Extensions</link:label>
    <link:label id="lab_arnc_DebtInstrumentNumberofExtensions_1BCB696B74155F2F6D72E2A5AA943C1D_documentation_en-US" xlink:label="lab_arnc_DebtInstrumentNumberofExtensions_1BCB696B74155F2F6D72E2A5AA943C1D" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Debt Instrument, Number of Extensions</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_DebtInstrumentNumberofExtensions" xlink:label="loc_arnc_DebtInstrumentNumberofExtensions_1BCB696B74155F2F6D72E2A5AA943C1D" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_DebtInstrumentNumberofExtensions_1BCB696B74155F2F6D72E2A5AA943C1D" xlink:to="lab_arnc_DebtInstrumentNumberofExtensions_1BCB696B74155F2F6D72E2A5AA943C1D" xlink:type="arc" />
    <link:label id="lab_arnc_ExtendedAdditionalMaturityPeriod_33B2EAAB4788A450A504E2A5AA957056_terseLabel_en-US" xlink:label="lab_arnc_ExtendedAdditionalMaturityPeriod_33B2EAAB4788A450A504E2A5AA957056" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Extension of maturity period</link:label>
    <link:label id="lab_arnc_ExtendedAdditionalMaturityPeriod_33B2EAAB4788A450A504E2A5AA957056_label_en-US" xlink:label="lab_arnc_ExtendedAdditionalMaturityPeriod_33B2EAAB4788A450A504E2A5AA957056" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Extended Additional Maturity Period</link:label>
    <link:label id="lab_arnc_ExtendedAdditionalMaturityPeriod_33B2EAAB4788A450A504E2A5AA957056_documentation_en-US" xlink:label="lab_arnc_ExtendedAdditionalMaturityPeriod_33B2EAAB4788A450A504E2A5AA957056" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Extended additional maturity period.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_ExtendedAdditionalMaturityPeriod" xlink:label="loc_arnc_ExtendedAdditionalMaturityPeriod_33B2EAAB4788A450A504E2A5AA957056" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_ExtendedAdditionalMaturityPeriod_33B2EAAB4788A450A504E2A5AA957056" xlink:to="lab_arnc_ExtendedAdditionalMaturityPeriod_33B2EAAB4788A450A504E2A5AA957056" xlink:type="arc" />
    <link:label id="lab_us-gaap_LineOfCreditFacilityCommitmentFeePercentage_EC2DBAA22EED71A4D7DFE2A5AA956ACA_terseLabel_en-US" xlink:label="lab_us-gaap_LineOfCreditFacilityCommitmentFeePercentage_EC2DBAA22EED71A4D7DFE2A5AA956ACA" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Fees paid to maintain credit facility</link:label>
    <link:label id="lab_us-gaap_LineOfCreditFacilityCommitmentFeePercentage_EC2DBAA22EED71A4D7DFE2A5AA956ACA_label_en-US" xlink:label="lab_us-gaap_LineOfCreditFacilityCommitmentFeePercentage_EC2DBAA22EED71A4D7DFE2A5AA956ACA" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Line of Credit Facility, Commitment Fee Percentage</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_LineOfCreditFacilityCommitmentFeePercentage" xlink:label="loc_us-gaap_LineOfCreditFacilityCommitmentFeePercentage_EC2DBAA22EED71A4D7DFE2A5AA956ACA" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LineOfCreditFacilityCommitmentFeePercentage_EC2DBAA22EED71A4D7DFE2A5AA956ACA" xlink:to="lab_us-gaap_LineOfCreditFacilityCommitmentFeePercentage_EC2DBAA22EED71A4D7DFE2A5AA956ACA" xlink:type="arc" />
    <link:label id="lab_arnc_ApplicableMarginOnLiborLoans_10DEF049DF6B7AC3DFD2E2A5AA95A0CF_terseLabel_en-US" xlink:label="lab_arnc_ApplicableMarginOnLiborLoans_10DEF049DF6B7AC3DFD2E2A5AA95A0CF" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Applicable margin on LIBOR loans</link:label>
    <link:label id="lab_arnc_ApplicableMarginOnLiborLoans_10DEF049DF6B7AC3DFD2E2A5AA95A0CF_label_en-US" xlink:label="lab_arnc_ApplicableMarginOnLiborLoans_10DEF049DF6B7AC3DFD2E2A5AA95A0CF" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Applicable Margin On Libor Loans</link:label>
    <link:label id="lab_arnc_ApplicableMarginOnLiborLoans_10DEF049DF6B7AC3DFD2E2A5AA95A0CF_documentation_en-US" xlink:label="lab_arnc_ApplicableMarginOnLiborLoans_10DEF049DF6B7AC3DFD2E2A5AA95A0CF" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Applicable margin on LIBOR loans.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_ApplicableMarginOnLiborLoans" xlink:label="loc_arnc_ApplicableMarginOnLiborLoans_10DEF049DF6B7AC3DFD2E2A5AA95A0CF" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_ApplicableMarginOnLiborLoans_10DEF049DF6B7AC3DFD2E2A5AA95A0CF" xlink:to="lab_arnc_ApplicableMarginOnLiborLoans_10DEF049DF6B7AC3DFD2E2A5AA95A0CF" xlink:type="arc" />
    <link:label id="lab_arnc_MinimumIndebtednessforOtherPrincipalAmounts_1A3645B5EA3B29750D00E2A5AA95EE5A_terseLabel_en-US" xlink:label="lab_arnc_MinimumIndebtednessforOtherPrincipalAmounts_1A3645B5EA3B29750D00E2A5AA95EE5A" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Amount of principal indebtedness that would cause default</link:label>
    <link:label id="lab_arnc_MinimumIndebtednessforOtherPrincipalAmounts_1A3645B5EA3B29750D00E2A5AA95EE5A_label_en-US" xlink:label="lab_arnc_MinimumIndebtednessforOtherPrincipalAmounts_1A3645B5EA3B29750D00E2A5AA95EE5A" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Minimum Indebtedness for Other Principal Amounts</link:label>
    <link:label id="lab_arnc_MinimumIndebtednessforOtherPrincipalAmounts_1A3645B5EA3B29750D00E2A5AA95EE5A_documentation_en-US" xlink:label="lab_arnc_MinimumIndebtednessforOtherPrincipalAmounts_1A3645B5EA3B29750D00E2A5AA95EE5A" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Minimum Indebtedness for Other Principal Amounts</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_MinimumIndebtednessforOtherPrincipalAmounts" xlink:label="loc_arnc_MinimumIndebtednessforOtherPrincipalAmounts_1A3645B5EA3B29750D00E2A5AA95EE5A" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_MinimumIndebtednessforOtherPrincipalAmounts_1A3645B5EA3B29750D00E2A5AA95EE5A" xlink:to="lab_arnc_MinimumIndebtednessforOtherPrincipalAmounts_1A3645B5EA3B29750D00E2A5AA95EE5A" xlink:type="arc" />
    <link:label id="lab_us-gaap_ProceedsFromLongTermLinesOfCredit_AB3F078BBD384331E7D9E2A5AA9597E3_terseLabel_en-US" xlink:label="lab_us-gaap_ProceedsFromLongTermLinesOfCredit_AB3F078BBD384331E7D9E2A5AA9597E3" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Amounts borrowed under the credit agreement</link:label>
    <link:label id="lab_us-gaap_ProceedsFromLongTermLinesOfCredit_AB3F078BBD384331E7D9E2A5AA9597E3_label_en-US" xlink:label="lab_us-gaap_ProceedsFromLongTermLinesOfCredit_AB3F078BBD384331E7D9E2A5AA9597E3" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Proceeds from Long-term Lines of Credit</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ProceedsFromLongTermLinesOfCredit" xlink:label="loc_us-gaap_ProceedsFromLongTermLinesOfCredit_AB3F078BBD384331E7D9E2A5AA9597E3" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ProceedsFromLongTermLinesOfCredit_AB3F078BBD384331E7D9E2A5AA9597E3" xlink:to="lab_us-gaap_ProceedsFromLongTermLinesOfCredit_AB3F078BBD384331E7D9E2A5AA9597E3" xlink:type="arc" />
    <link:label id="lab_us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity_4E675FFECF15D11370D3E2A5AA952A64_terseLabel_en-US" xlink:label="lab_us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity_4E675FFECF15D11370D3E2A5AA952A64" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Maximum borrowing capacity</link:label>
    <link:label id="lab_us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity_4E675FFECF15D11370D3E2A5AA952A64_label_en-US" xlink:label="lab_us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity_4E675FFECF15D11370D3E2A5AA952A64" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Line of Credit Facility, Maximum Borrowing Capacity</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity" xlink:label="loc_us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity_4E675FFECF15D11370D3E2A5AA952A64" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity_4E675FFECF15D11370D3E2A5AA952A64" xlink:to="lab_us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity_4E675FFECF15D11370D3E2A5AA952A64" xlink:type="arc" />
    <link:label id="lab_us-gaap_DebtInstrumentCarryingAmount_F043C93F3110DDB70DA8E2A5AA96C848_terseLabel_en-US" xlink:label="lab_us-gaap_DebtInstrumentCarryingAmount_F043C93F3110DDB70DA8E2A5AA96C848" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Aggregate outstanding principal amount</link:label>
    <link:label id="lab_us-gaap_DebtInstrumentCarryingAmount_F043C93F3110DDB70DA8E2A5AA96C848_label_en-US" xlink:label="lab_us-gaap_DebtInstrumentCarryingAmount_F043C93F3110DDB70DA8E2A5AA96C848" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Long-term Debt, Gross</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DebtInstrumentCarryingAmount" xlink:label="loc_us-gaap_DebtInstrumentCarryingAmount_F043C93F3110DDB70DA8E2A5AA96C848" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DebtInstrumentCarryingAmount_F043C93F3110DDB70DA8E2A5AA96C848" xlink:to="lab_us-gaap_DebtInstrumentCarryingAmount_F043C93F3110DDB70DA8E2A5AA96C848" xlink:type="arc" />
    <link:label id="lab_us-gaap_ProceedsFromLinesOfCredit_30967518B7D34E06D6CEE2A5AA96712E_terseLabel_en-US" xlink:label="lab_us-gaap_ProceedsFromLinesOfCredit_30967518B7D34E06D6CEE2A5AA96712E" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Proceeds from lines of credit</link:label>
    <link:label id="lab_us-gaap_ProceedsFromLinesOfCredit_30967518B7D34E06D6CEE2A5AA96712E_label_en-US" xlink:label="lab_us-gaap_ProceedsFromLinesOfCredit_30967518B7D34E06D6CEE2A5AA96712E" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Proceeds from Lines of Credit</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ProceedsFromLinesOfCredit" xlink:label="loc_us-gaap_ProceedsFromLinesOfCredit_30967518B7D34E06D6CEE2A5AA96712E" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ProceedsFromLinesOfCredit_30967518B7D34E06D6CEE2A5AA96712E" xlink:to="lab_us-gaap_ProceedsFromLinesOfCredit_30967518B7D34E06D6CEE2A5AA96712E" xlink:type="arc" />
    <link:label id="lab_us-gaap_RepaymentsOfLinesOfCredit_4D64440294565C46245BE2A5AA96EA65_terseLabel_en-US" xlink:label="lab_us-gaap_RepaymentsOfLinesOfCredit_4D64440294565C46245BE2A5AA96EA65" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Line of credit facility, repayment</link:label>
    <link:label id="lab_us-gaap_RepaymentsOfLinesOfCredit_4D64440294565C46245BE2A5AA96EA65_label_en-US" xlink:label="lab_us-gaap_RepaymentsOfLinesOfCredit_4D64440294565C46245BE2A5AA96EA65" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Repayments of Lines of Credit</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RepaymentsOfLinesOfCredit" xlink:label="loc_us-gaap_RepaymentsOfLinesOfCredit_4D64440294565C46245BE2A5AA96EA65" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RepaymentsOfLinesOfCredit_4D64440294565C46245BE2A5AA96EA65" xlink:to="lab_us-gaap_RepaymentsOfLinesOfCredit_4D64440294565C46245BE2A5AA96EA65" xlink:type="arc" />
    <link:label id="lab_arnc_WeightedAverageInterestRateOutstandingBorrowings_63CCF821BB6EA09D593CE2A5AA96459A_terseLabel_en-US" xlink:label="lab_arnc_WeightedAverageInterestRateOutstandingBorrowings_63CCF821BB6EA09D593CE2A5AA96459A" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Weighted-average interest rate</link:label>
    <link:label id="lab_arnc_WeightedAverageInterestRateOutstandingBorrowings_63CCF821BB6EA09D593CE2A5AA96459A_label_en-US" xlink:label="lab_arnc_WeightedAverageInterestRateOutstandingBorrowings_63CCF821BB6EA09D593CE2A5AA96459A" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Weighted Average Interest Rate Outstanding Borrowings</link:label>
    <link:label id="lab_arnc_WeightedAverageInterestRateOutstandingBorrowings_63CCF821BB6EA09D593CE2A5AA96459A_documentation_en-US" xlink:label="lab_arnc_WeightedAverageInterestRateOutstandingBorrowings_63CCF821BB6EA09D593CE2A5AA96459A" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Weighted average interest rate, outstanding borrowings.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_WeightedAverageInterestRateOutstandingBorrowings" xlink:label="loc_arnc_WeightedAverageInterestRateOutstandingBorrowings_63CCF821BB6EA09D593CE2A5AA96459A" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_WeightedAverageInterestRateOutstandingBorrowings_63CCF821BB6EA09D593CE2A5AA96459A" xlink:to="lab_arnc_WeightedAverageInterestRateOutstandingBorrowings_63CCF821BB6EA09D593CE2A5AA96459A" xlink:type="arc" />
    <link:label id="lab_arnc_DebtWeightedAverageMaturityTerm_A1975A1F2019C165537EE2A5AA96FAF9_terseLabel_en-US" xlink:label="lab_arnc_DebtWeightedAverageMaturityTerm_A1975A1F2019C165537EE2A5AA96FAF9" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Weighted-average maturity days</link:label>
    <link:label id="lab_arnc_DebtWeightedAverageMaturityTerm_A1975A1F2019C165537EE2A5AA96FAF9_label_en-US" xlink:label="lab_arnc_DebtWeightedAverageMaturityTerm_A1975A1F2019C165537EE2A5AA96FAF9" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Debt Weighted Average Maturity Term</link:label>
    <link:label id="lab_arnc_DebtWeightedAverageMaturityTerm_A1975A1F2019C165537EE2A5AA96FAF9_documentation_en-US" xlink:label="lab_arnc_DebtWeightedAverageMaturityTerm_A1975A1F2019C165537EE2A5AA96FAF9" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Debt Weighted Average Maturity Term</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_DebtWeightedAverageMaturityTerm" xlink:label="loc_arnc_DebtWeightedAverageMaturityTerm_A1975A1F2019C165537EE2A5AA96FAF9" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_DebtWeightedAverageMaturityTerm_A1975A1F2019C165537EE2A5AA96FAF9" xlink:to="lab_arnc_DebtWeightedAverageMaturityTerm_A1975A1F2019C165537EE2A5AA96FAF9" xlink:type="arc" />
    <link:label id="lab_us-gaap_EmployeeSeveranceMember_D12E2834034865F663C306CA4194107B_terseLabel_en-US" xlink:label="lab_us-gaap_EmployeeSeveranceMember_D12E2834034865F663C306CA4194107B" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Layoff costs</link:label>
    <link:label id="lab_us-gaap_EmployeeSeveranceMember_D12E2834034865F663C306CA4194107B_label_en-US" xlink:label="lab_us-gaap_EmployeeSeveranceMember_D12E2834034865F663C306CA4194107B" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Employee Severance [Member]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_EmployeeSeveranceMember" xlink:label="loc_us-gaap_EmployeeSeveranceMember_D12E2834034865F663C306CA4194107B" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_EmployeeSeveranceMember_D12E2834034865F663C306CA4194107B" xlink:to="lab_us-gaap_EmployeeSeveranceMember_D12E2834034865F663C306CA4194107B" xlink:type="arc" />
    <link:label id="lab_arnc_EmployeeSeveranceReversalOfPriorRestructuringMember_5901179F791D9A6507E306CA4194C869_terseLabel_en-US" xlink:label="lab_arnc_EmployeeSeveranceReversalOfPriorRestructuringMember_5901179F791D9A6507E306CA4194C869" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Reversal of prior restructuring charges</link:label>
    <link:label id="lab_arnc_EmployeeSeveranceReversalOfPriorRestructuringMember_5901179F791D9A6507E306CA4194C869_label_en-US" xlink:label="lab_arnc_EmployeeSeveranceReversalOfPriorRestructuringMember_5901179F791D9A6507E306CA4194C869" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Employee Severance, Reversal Of Prior Restructuring [Member]</link:label>
    <link:label id="lab_arnc_EmployeeSeveranceReversalOfPriorRestructuringMember_5901179F791D9A6507E306CA4194C869_documentation_en-US" xlink:label="lab_arnc_EmployeeSeveranceReversalOfPriorRestructuringMember_5901179F791D9A6507E306CA4194C869" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Employee Severance, Reversal Of Prior Restructuring [Member]</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_EmployeeSeveranceReversalOfPriorRestructuringMember" xlink:label="loc_arnc_EmployeeSeveranceReversalOfPriorRestructuringMember_5901179F791D9A6507E306CA4194C869" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_EmployeeSeveranceReversalOfPriorRestructuringMember_5901179F791D9A6507E306CA4194C869" xlink:to="lab_arnc_EmployeeSeveranceReversalOfPriorRestructuringMember_5901179F791D9A6507E306CA4194C869" xlink:type="arc" />
    <link:label id="lab_arnc_EmployeeSeveranceCostsStockAwardReversalsMember_0AA41D0AFCD2DA0B654A06CA4195776C_terseLabel_en-US" xlink:label="lab_arnc_EmployeeSeveranceCostsStockAwardReversalsMember_0AA41D0AFCD2DA0B654A06CA4195776C" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Reclassification of a stock awards reversal</link:label>
    <link:label id="lab_arnc_EmployeeSeveranceCostsStockAwardReversalsMember_0AA41D0AFCD2DA0B654A06CA4195776C_label_en-US" xlink:label="lab_arnc_EmployeeSeveranceCostsStockAwardReversalsMember_0AA41D0AFCD2DA0B654A06CA4195776C" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Employee Severance Costs, Stock Award Reversals [Member]</link:label>
    <link:label id="lab_arnc_EmployeeSeveranceCostsStockAwardReversalsMember_0AA41D0AFCD2DA0B654A06CA4195776C_documentation_en-US" xlink:label="lab_arnc_EmployeeSeveranceCostsStockAwardReversalsMember_0AA41D0AFCD2DA0B654A06CA4195776C" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Employee Severance Costs, Stock Award Reversals</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_EmployeeSeveranceCostsStockAwardReversalsMember" xlink:label="loc_arnc_EmployeeSeveranceCostsStockAwardReversalsMember_0AA41D0AFCD2DA0B654A06CA4195776C" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_EmployeeSeveranceCostsStockAwardReversalsMember_0AA41D0AFCD2DA0B654A06CA4195776C" xlink:to="lab_arnc_EmployeeSeveranceCostsStockAwardReversalsMember_0AA41D0AFCD2DA0B654A06CA4195776C" xlink:type="arc" />
    <link:label id="lab_arnc_EmployeeSeveranceCostReclassificationOfPensionCostsMember_6F38688B7F2FED169C9E06CA4195FBAF_terseLabel_en-US" xlink:label="lab_arnc_EmployeeSeveranceCostReclassificationOfPensionCostsMember_6F38688B7F2FED169C9E06CA4195FBAF" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Reclassification of pension costs</link:label>
    <link:label id="lab_arnc_EmployeeSeveranceCostReclassificationOfPensionCostsMember_6F38688B7F2FED169C9E06CA4195FBAF_label_en-US" xlink:label="lab_arnc_EmployeeSeveranceCostReclassificationOfPensionCostsMember_6F38688B7F2FED169C9E06CA4195FBAF" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Employee Severance Cost, Reclassification Of Pension Costs [Member]</link:label>
    <link:label id="lab_arnc_EmployeeSeveranceCostReclassificationOfPensionCostsMember_6F38688B7F2FED169C9E06CA4195FBAF_documentation_en-US" xlink:label="lab_arnc_EmployeeSeveranceCostReclassificationOfPensionCostsMember_6F38688B7F2FED169C9E06CA4195FBAF" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Employee Severance Cost, Reclassification Of Pension Costs [Member]</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_EmployeeSeveranceCostReclassificationOfPensionCostsMember" xlink:label="loc_arnc_EmployeeSeveranceCostReclassificationOfPensionCostsMember_6F38688B7F2FED169C9E06CA4195FBAF" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_EmployeeSeveranceCostReclassificationOfPensionCostsMember_6F38688B7F2FED169C9E06CA4195FBAF" xlink:to="lab_arnc_EmployeeSeveranceCostReclassificationOfPensionCostsMember_6F38688B7F2FED169C9E06CA4195FBAF" xlink:type="arc" />
    <link:label id="lab_arnc_EmployeeSeveranceCostEffectsOfForeignCurrencyTranslationAndOtherMember_93172CEEF131C3E2881C06CA4195BC10_terseLabel_en-US" xlink:label="lab_arnc_EmployeeSeveranceCostEffectsOfForeignCurrencyTranslationAndOtherMember_93172CEEF131C3E2881C06CA4195BC10" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Effects of foreign currency translation and other</link:label>
    <link:label id="lab_arnc_EmployeeSeveranceCostEffectsOfForeignCurrencyTranslationAndOtherMember_93172CEEF131C3E2881C06CA4195BC10_label_en-US" xlink:label="lab_arnc_EmployeeSeveranceCostEffectsOfForeignCurrencyTranslationAndOtherMember_93172CEEF131C3E2881C06CA4195BC10" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Employee Severance Cost, Effects Of Foreign Currency Translation And Other [Member]</link:label>
    <link:label id="lab_arnc_EmployeeSeveranceCostEffectsOfForeignCurrencyTranslationAndOtherMember_93172CEEF131C3E2881C06CA4195BC10_documentation_en-US" xlink:label="lab_arnc_EmployeeSeveranceCostEffectsOfForeignCurrencyTranslationAndOtherMember_93172CEEF131C3E2881C06CA4195BC10" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Employee Severance Cost, Effects Of Foreign Currency Translation And Other [Member]</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_EmployeeSeveranceCostEffectsOfForeignCurrencyTranslationAndOtherMember" xlink:label="loc_arnc_EmployeeSeveranceCostEffectsOfForeignCurrencyTranslationAndOtherMember_93172CEEF131C3E2881C06CA4195BC10" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_EmployeeSeveranceCostEffectsOfForeignCurrencyTranslationAndOtherMember_93172CEEF131C3E2881C06CA4195BC10" xlink:to="lab_arnc_EmployeeSeveranceCostEffectsOfForeignCurrencyTranslationAndOtherMember_93172CEEF131C3E2881C06CA4195BC10" xlink:type="arc" />
    <link:label id="lab_arnc_EmployeeSeveranceCostsCreditInPostRetirementCostsMember_4BEE8FAB992B6900BEC406CA4195FC3C_terseLabel_en-US" xlink:label="lab_arnc_EmployeeSeveranceCostsCreditInPostRetirementCostsMember_4BEE8FAB992B6900BEC406CA4195FC3C" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Credit in post-retirement costs</link:label>
    <link:label id="lab_arnc_EmployeeSeveranceCostsCreditInPostRetirementCostsMember_4BEE8FAB992B6900BEC406CA4195FC3C_label_en-US" xlink:label="lab_arnc_EmployeeSeveranceCostsCreditInPostRetirementCostsMember_4BEE8FAB992B6900BEC406CA4195FC3C" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Employee Severance Costs, Credit In Post-Retirement Costs [Member]</link:label>
    <link:label id="lab_arnc_EmployeeSeveranceCostsCreditInPostRetirementCostsMember_4BEE8FAB992B6900BEC406CA4195FC3C_documentation_en-US" xlink:label="lab_arnc_EmployeeSeveranceCostsCreditInPostRetirementCostsMember_4BEE8FAB992B6900BEC406CA4195FC3C" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Employee Severance Costs, Credit In Post-Retirement Costs [Member]</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_EmployeeSeveranceCostsCreditInPostRetirementCostsMember" xlink:label="loc_arnc_EmployeeSeveranceCostsCreditInPostRetirementCostsMember_4BEE8FAB992B6900BEC406CA4195FC3C" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_EmployeeSeveranceCostsCreditInPostRetirementCostsMember_4BEE8FAB992B6900BEC406CA4195FC3C" xlink:to="lab_arnc_EmployeeSeveranceCostsCreditInPostRetirementCostsMember_4BEE8FAB992B6900BEC406CA4195FC3C" xlink:type="arc" />
    <link:label id="lab_arnc_OtherExitCostsMember_03AA95D4394356C91A9706CA4195D99C_terseLabel_en-US" xlink:label="lab_arnc_OtherExitCostsMember_03AA95D4394356C91A9706CA4195D99C" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Other exit costs</link:label>
    <link:label id="lab_arnc_OtherExitCostsMember_03AA95D4394356C91A9706CA4195D99C_label_en-US" xlink:label="lab_arnc_OtherExitCostsMember_03AA95D4394356C91A9706CA4195D99C" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Other Exit Costs [Member]</link:label>
    <link:label id="lab_arnc_OtherExitCostsMember_03AA95D4394356C91A9706CA4195D99C_documentation_en-US" xlink:label="lab_arnc_OtherExitCostsMember_03AA95D4394356C91A9706CA4195D99C" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Other exit costs.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_OtherExitCostsMember" xlink:label="loc_arnc_OtherExitCostsMember_03AA95D4394356C91A9706CA4195D99C" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_OtherExitCostsMember_03AA95D4394356C91A9706CA4195D99C" xlink:to="lab_arnc_OtherExitCostsMember_03AA95D4394356C91A9706CA4195D99C" xlink:type="arc" />
    <link:label id="lab_arnc_OtherExitCostsReclassificationofAssetRetirementMember_8EB4CAE23D9F79C4D29F06CA4196A906_terseLabel_en-US" xlink:label="lab_arnc_OtherExitCostsReclassificationofAssetRetirementMember_8EB4CAE23D9F79C4D29F06CA4196A906" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Reclassification of asset retirement obligation</link:label>
    <link:label id="lab_arnc_OtherExitCostsReclassificationofAssetRetirementMember_8EB4CAE23D9F79C4D29F06CA4196A906_label_en-US" xlink:label="lab_arnc_OtherExitCostsReclassificationofAssetRetirementMember_8EB4CAE23D9F79C4D29F06CA4196A906" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Other Exit Costs, Reclassification of Asset Retirement [Member]</link:label>
    <link:label id="lab_arnc_OtherExitCostsReclassificationofAssetRetirementMember_8EB4CAE23D9F79C4D29F06CA4196A906_documentation_en-US" xlink:label="lab_arnc_OtherExitCostsReclassificationofAssetRetirementMember_8EB4CAE23D9F79C4D29F06CA4196A906" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Other Exit Cost, Reclassification Of Asset Retirement [Member]</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_OtherExitCostsReclassificationofAssetRetirementMember" xlink:label="loc_arnc_OtherExitCostsReclassificationofAssetRetirementMember_8EB4CAE23D9F79C4D29F06CA4196A906" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_OtherExitCostsReclassificationofAssetRetirementMember_8EB4CAE23D9F79C4D29F06CA4196A906" xlink:to="lab_arnc_OtherExitCostsReclassificationofAssetRetirementMember_8EB4CAE23D9F79C4D29F06CA4196A906" xlink:type="arc" />
    <link:label id="lab_arnc_OtherExitCostsReclassificationOfEnvironmentalObligationMember_B3202E6BA8BB086A56D506CA419681AA_terseLabel_en-US" xlink:label="lab_arnc_OtherExitCostsReclassificationOfEnvironmentalObligationMember_B3202E6BA8BB086A56D506CA419681AA" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Reclassification of environmental obligation</link:label>
    <link:label id="lab_arnc_OtherExitCostsReclassificationOfEnvironmentalObligationMember_B3202E6BA8BB086A56D506CA419681AA_label_en-US" xlink:label="lab_arnc_OtherExitCostsReclassificationOfEnvironmentalObligationMember_B3202E6BA8BB086A56D506CA419681AA" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Other Exit Costs, Reclassification Of Environmental Obligation [Member]</link:label>
    <link:label id="lab_arnc_OtherExitCostsReclassificationOfEnvironmentalObligationMember_B3202E6BA8BB086A56D506CA419681AA_documentation_en-US" xlink:label="lab_arnc_OtherExitCostsReclassificationOfEnvironmentalObligationMember_B3202E6BA8BB086A56D506CA419681AA" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Other Exit Costs, Reclassification Of Environmental Obligation [Member]</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_OtherExitCostsReclassificationOfEnvironmentalObligationMember" xlink:label="loc_arnc_OtherExitCostsReclassificationOfEnvironmentalObligationMember_B3202E6BA8BB086A56D506CA419681AA" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_OtherExitCostsReclassificationOfEnvironmentalObligationMember_B3202E6BA8BB086A56D506CA419681AA" xlink:to="lab_arnc_OtherExitCostsReclassificationOfEnvironmentalObligationMember_B3202E6BA8BB086A56D506CA419681AA" xlink:type="arc" />
    <link:label id="lab_arnc_OtherExitCostsReclassificationofLegalObligationMember_07EC4A26E3AE6F7051F906CA4196C3EC_terseLabel_en-US" xlink:label="lab_arnc_OtherExitCostsReclassificationofLegalObligationMember_07EC4A26E3AE6F7051F906CA4196C3EC" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Reclassification of legal obligations</link:label>
    <link:label id="lab_arnc_OtherExitCostsReclassificationofLegalObligationMember_07EC4A26E3AE6F7051F906CA4196C3EC_label_en-US" xlink:label="lab_arnc_OtherExitCostsReclassificationofLegalObligationMember_07EC4A26E3AE6F7051F906CA4196C3EC" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Other Exit Costs, Reclassification of Legal Obligation [Member]</link:label>
    <link:label id="lab_arnc_OtherExitCostsReclassificationofLegalObligationMember_07EC4A26E3AE6F7051F906CA4196C3EC_documentation_en-US" xlink:label="lab_arnc_OtherExitCostsReclassificationofLegalObligationMember_07EC4A26E3AE6F7051F906CA4196C3EC" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Other Exit Costs, Reclassification of Legal Obligation</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_OtherExitCostsReclassificationofLegalObligationMember" xlink:label="loc_arnc_OtherExitCostsReclassificationofLegalObligationMember_07EC4A26E3AE6F7051F906CA4196C3EC" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_OtherExitCostsReclassificationofLegalObligationMember_07EC4A26E3AE6F7051F906CA4196C3EC" xlink:to="lab_arnc_OtherExitCostsReclassificationofLegalObligationMember_07EC4A26E3AE6F7051F906CA4196C3EC" xlink:type="arc" />
    <link:label id="lab_us-gaap_EnvironmentalRemediationMember_DC111DD71C87D1BC963706CA41969707_terseLabel_en-US" xlink:label="lab_us-gaap_EnvironmentalRemediationMember_DC111DD71C87D1BC963706CA41969707" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Environmental Remediation</link:label>
    <link:label id="lab_us-gaap_EnvironmentalRemediationMember_DC111DD71C87D1BC963706CA41969707_label_en-US" xlink:label="lab_us-gaap_EnvironmentalRemediationMember_DC111DD71C87D1BC963706CA41969707" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Environmental Remediation [Member]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_EnvironmentalRemediationMember" xlink:label="loc_us-gaap_EnvironmentalRemediationMember_DC111DD71C87D1BC963706CA41969707" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_EnvironmentalRemediationMember_DC111DD71C87D1BC963706CA41969707" xlink:to="lab_us-gaap_EnvironmentalRemediationMember_DC111DD71C87D1BC963706CA41969707" xlink:type="arc" />
    <link:label id="lab_us-gaap_ContractTerminationMember_EE9AFEA53C1DD0ECD9FC06CA4196C9DB_terseLabel_en-US" xlink:label="lab_us-gaap_ContractTerminationMember_EE9AFEA53C1DD0ECD9FC06CA4196C9DB" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Contract Termination</link:label>
    <link:label id="lab_us-gaap_ContractTerminationMember_EE9AFEA53C1DD0ECD9FC06CA4196C9DB_label_en-US" xlink:label="lab_us-gaap_ContractTerminationMember_EE9AFEA53C1DD0ECD9FC06CA4196C9DB" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Contract Termination [Member]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ContractTerminationMember" xlink:label="loc_us-gaap_ContractTerminationMember_EE9AFEA53C1DD0ECD9FC06CA4196C9DB" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ContractTerminationMember_EE9AFEA53C1DD0ECD9FC06CA4196C9DB" xlink:to="lab_us-gaap_ContractTerminationMember_EE9AFEA53C1DD0ECD9FC06CA4196C9DB" xlink:type="arc" />
    <link:label id="lab_us-gaap_RestructuringReserveRollForward_C97674DF38E1B548B0D006CA4197A742_terseLabel_en-US" xlink:label="lab_us-gaap_RestructuringReserveRollForward_C97674DF38E1B548B0D006CA4197A742" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Restructuring Reserve [Roll Forward]</link:label>
    <link:label id="lab_us-gaap_RestructuringReserveRollForward_C97674DF38E1B548B0D006CA4197A742_label_en-US" xlink:label="lab_us-gaap_RestructuringReserveRollForward_C97674DF38E1B548B0D006CA4197A742" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Restructuring Reserve [Roll Forward]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RestructuringReserveRollForward" xlink:label="loc_us-gaap_RestructuringReserveRollForward_C97674DF38E1B548B0D006CA4197A742" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RestructuringReserveRollForward_C97674DF38E1B548B0D006CA4197A742" xlink:to="lab_us-gaap_RestructuringReserveRollForward_C97674DF38E1B548B0D006CA4197A742" xlink:type="arc" />
    <link:label id="lab_us-gaap_RestructuringReserve_3CBD4E19841DFFAF012206CA41978244_periodStartLabel_en-US" xlink:label="lab_us-gaap_RestructuringReserve_3CBD4E19841DFFAF012206CA41978244" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel" xlink:type="resource" xml:lang="en-US">Restructuring reserve beginning balance</link:label>
    <link:label id="lab_us-gaap_RestructuringReserve_3CBD4E19841DFFAF012206CA41978244_label_en-US" xlink:label="lab_us-gaap_RestructuringReserve_3CBD4E19841DFFAF012206CA41978244" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Restructuring Reserve</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RestructuringReserve" xlink:label="loc_us-gaap_RestructuringReserve_3CBD4E19841DFFAF012206CA41978244" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RestructuringReserve_3CBD4E19841DFFAF012206CA41978244" xlink:to="lab_us-gaap_RestructuringReserve_3CBD4E19841DFFAF012206CA41978244" xlink:type="arc" />
    <link:label id="lab_us-gaap_PaymentsForRestructuring_6A8B011C6C3236577EA306CA4197F726_negatedLabel_en-US" xlink:label="lab_us-gaap_PaymentsForRestructuring_6A8B011C6C3236577EA306CA4197F726" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xml:lang="en-US">Cash payments</link:label>
    <link:label id="lab_us-gaap_PaymentsForRestructuring_6A8B011C6C3236577EA306CA4197F726_label_en-US" xlink:label="lab_us-gaap_PaymentsForRestructuring_6A8B011C6C3236577EA306CA4197F726" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Payments for Restructuring</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PaymentsForRestructuring" xlink:label="loc_us-gaap_PaymentsForRestructuring_6A8B011C6C3236577EA306CA4197F726" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PaymentsForRestructuring_6A8B011C6C3236577EA306CA4197F726" xlink:to="lab_us-gaap_PaymentsForRestructuring_6A8B011C6C3236577EA306CA4197F726" xlink:type="arc" />
    <link:label id="lab_arnc_RestructuringReservePeriodExpenses_B4BE900354FFED4491A006CA4197B2B0_terseLabel_en-US" xlink:label="lab_arnc_RestructuringReservePeriodExpenses_B4BE900354FFED4491A006CA4197B2B0" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Restructuring charges</link:label>
    <link:label id="lab_arnc_RestructuringReservePeriodExpenses_B4BE900354FFED4491A006CA4197B2B0_label_en-US" xlink:label="lab_arnc_RestructuringReservePeriodExpenses_B4BE900354FFED4491A006CA4197B2B0" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Restructuring Reserve Period Expenses</link:label>
    <link:label id="lab_arnc_RestructuringReservePeriodExpenses_B4BE900354FFED4491A006CA4197B2B0_documentation_en-US" xlink:label="lab_arnc_RestructuringReservePeriodExpenses_B4BE900354FFED4491A006CA4197B2B0" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Restructuring reserve period expenses.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_RestructuringReservePeriodExpenses" xlink:label="loc_arnc_RestructuringReservePeriodExpenses_B4BE900354FFED4491A006CA4197B2B0" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_RestructuringReservePeriodExpenses_B4BE900354FFED4491A006CA4197B2B0" xlink:to="lab_arnc_RestructuringReservePeriodExpenses_B4BE900354FFED4491A006CA4197B2B0" xlink:type="arc" />
    <link:label id="lab_us-gaap_RestructuringReserveAccrualAdjustment1_34403D90A879075765D206CA41971407_negatedTerseLabel_en-US" xlink:label="lab_us-gaap_RestructuringReserveAccrualAdjustment1_34403D90A879075765D206CA41971407" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:type="resource" xml:lang="en-US">Other</link:label>
    <link:label id="lab_us-gaap_RestructuringReserveAccrualAdjustment1_34403D90A879075765D206CA41971407_label_en-US" xlink:label="lab_us-gaap_RestructuringReserveAccrualAdjustment1_34403D90A879075765D206CA41971407" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Restructuring Reserve, Accrual Adjustment</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RestructuringReserveAccrualAdjustment1" xlink:label="loc_us-gaap_RestructuringReserveAccrualAdjustment1_34403D90A879075765D206CA41971407" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RestructuringReserveAccrualAdjustment1_34403D90A879075765D206CA41971407" xlink:to="lab_us-gaap_RestructuringReserveAccrualAdjustment1_34403D90A879075765D206CA41971407" xlink:type="arc" />
    <link:label id="lab_us-gaap_RestructuringReserve_1A557D65A767203A4EFA06CA4198F069_periodEndLabel_en-US" xlink:label="lab_us-gaap_RestructuringReserve_1A557D65A767203A4EFA06CA4198F069" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel" xlink:type="resource" xml:lang="en-US">Restructuring reserve ending balance</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RestructuringReserve" xlink:label="loc_us-gaap_RestructuringReserve_1A557D65A767203A4EFA06CA4198F069" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RestructuringReserve_1A557D65A767203A4EFA06CA4198F069" xlink:to="lab_us-gaap_RestructuringReserve_1A557D65A767203A4EFA06CA4198F069" xlink:type="arc" />
    <link:label id="lab_us-gaap_PropertyPlantAndEquipmentAbstract_171059E1F46D18937F8CE244A9CA701E_label_en-US" xlink:label="lab_us-gaap_PropertyPlantAndEquipmentAbstract_171059E1F46D18937F8CE244A9CA701E" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Property, Plant and Equipment [Abstract]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PropertyPlantAndEquipmentAbstract" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentAbstract_171059E1F46D18937F8CE244A9CA701E" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentAbstract_171059E1F46D18937F8CE244A9CA701E" xlink:to="lab_us-gaap_PropertyPlantAndEquipmentAbstract_171059E1F46D18937F8CE244A9CA701E" xlink:type="arc" />
    <link:label id="lab_us-gaap_PropertyPlantAndEquipmentDisclosureTextBlock_E4BCE604470EFA60259DE244A9CAD83C_terseLabel_en-US" xlink:label="lab_us-gaap_PropertyPlantAndEquipmentDisclosureTextBlock_E4BCE604470EFA60259DE244A9CAD83C" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Properties, Plants, and Equipment, Net</link:label>
    <link:label id="lab_us-gaap_PropertyPlantAndEquipmentDisclosureTextBlock_E4BCE604470EFA60259DE244A9CAD83C_label_en-US" xlink:label="lab_us-gaap_PropertyPlantAndEquipmentDisclosureTextBlock_E4BCE604470EFA60259DE244A9CAD83C" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Property, Plant and Equipment Disclosure [Text Block]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PropertyPlantAndEquipmentDisclosureTextBlock" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentDisclosureTextBlock_E4BCE604470EFA60259DE244A9CAD83C" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentDisclosureTextBlock_E4BCE604470EFA60259DE244A9CAD83C" xlink:to="lab_us-gaap_PropertyPlantAndEquipmentDisclosureTextBlock_E4BCE604470EFA60259DE244A9CAD83C" xlink:type="arc" />
    <link:label id="lab_us-gaap_DisaggregationOfRevenueTableTextBlock_4E205FBFA756054C13D1CB2CEAB3594C_terseLabel_en-US" xlink:label="lab_us-gaap_DisaggregationOfRevenueTableTextBlock_4E205FBFA756054C13D1CB2CEAB3594C" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Schedule of Revenue by Major End Market and Reporting Segments</link:label>
    <link:label id="lab_us-gaap_DisaggregationOfRevenueTableTextBlock_4E205FBFA756054C13D1CB2CEAB3594C_label_en-US" xlink:label="lab_us-gaap_DisaggregationOfRevenueTableTextBlock_4E205FBFA756054C13D1CB2CEAB3594C" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Disaggregation of Revenue [Table Text Block]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DisaggregationOfRevenueTableTextBlock" xlink:label="loc_us-gaap_DisaggregationOfRevenueTableTextBlock_4E205FBFA756054C13D1CB2CEAB3594C" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DisaggregationOfRevenueTableTextBlock_4E205FBFA756054C13D1CB2CEAB3594C" xlink:to="lab_us-gaap_DisaggregationOfRevenueTableTextBlock_4E205FBFA756054C13D1CB2CEAB3594C" xlink:type="arc" />
    <link:label id="lab_us-gaap_RestructuringAndRelatedActivitiesDisclosureTextBlock_E09342C394C9AED97DEA7C362FF13D71_terseLabel_en-US" xlink:label="lab_us-gaap_RestructuringAndRelatedActivitiesDisclosureTextBlock_E09342C394C9AED97DEA7C362FF13D71" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Restructuring and Other Charges</link:label>
    <link:label id="lab_us-gaap_RestructuringAndRelatedActivitiesDisclosureTextBlock_E09342C394C9AED97DEA7C362FF13D71_label_en-US" xlink:label="lab_us-gaap_RestructuringAndRelatedActivitiesDisclosureTextBlock_E09342C394C9AED97DEA7C362FF13D71" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Restructuring and Related Activities Disclosure [Text Block]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RestructuringAndRelatedActivitiesDisclosureTextBlock" xlink:label="loc_us-gaap_RestructuringAndRelatedActivitiesDisclosureTextBlock_E09342C394C9AED97DEA7C362FF13D71" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RestructuringAndRelatedActivitiesDisclosureTextBlock_E09342C394C9AED97DEA7C362FF13D71" xlink:to="lab_us-gaap_RestructuringAndRelatedActivitiesDisclosureTextBlock_E09342C394C9AED97DEA7C362FF13D71" xlink:type="arc" />
    <link:label id="lab_us-gaap_IncomeStatementAbstract_24253AA54D9944437A070256633F0566_label_en-US" xlink:label="lab_us-gaap_IncomeStatementAbstract_24253AA54D9944437A070256633F0566" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Income Statement [Abstract]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_IncomeStatementAbstract" xlink:label="loc_us-gaap_IncomeStatementAbstract_24253AA54D9944437A070256633F0566" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncomeStatementAbstract_24253AA54D9944437A070256633F0566" xlink:to="lab_us-gaap_IncomeStatementAbstract_24253AA54D9944437A070256633F0566" xlink:type="arc" />
    <link:label id="lab_us-gaap_CostOfGoodsSoldExcludingDepreciationDepletionAndAmortization_7450360D5BC706C383B30256633FE1F2_terseLabel_en-US" xlink:label="lab_us-gaap_CostOfGoodsSoldExcludingDepreciationDepletionAndAmortization_7450360D5BC706C383B30256633FE1F2" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Cost of goods sold (exclusive of expenses below)</link:label>
    <link:label id="lab_us-gaap_CostOfGoodsSoldExcludingDepreciationDepletionAndAmortization_7450360D5BC706C383B30256633FE1F2_label_en-US" xlink:label="lab_us-gaap_CostOfGoodsSoldExcludingDepreciationDepletionAndAmortization_7450360D5BC706C383B30256633FE1F2" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Cost of Goods Sold, Excluding Depreciation, Depletion, and Amortization</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_CostOfGoodsSoldExcludingDepreciationDepletionAndAmortization" xlink:label="loc_us-gaap_CostOfGoodsSoldExcludingDepreciationDepletionAndAmortization_7450360D5BC706C383B30256633FE1F2" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CostOfGoodsSoldExcludingDepreciationDepletionAndAmortization_7450360D5BC706C383B30256633FE1F2" xlink:to="lab_us-gaap_CostOfGoodsSoldExcludingDepreciationDepletionAndAmortization_7450360D5BC706C383B30256633FE1F2" xlink:type="arc" />
    <link:label id="lab_us-gaap_SellingGeneralAndAdministrativeExpense_E1033A8C53383FAA338A0256633F9350_terseLabel_en-US" xlink:label="lab_us-gaap_SellingGeneralAndAdministrativeExpense_E1033A8C53383FAA338A0256633F9350" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Selling, general administrative, and other expenses</link:label>
    <link:label id="lab_us-gaap_SellingGeneralAndAdministrativeExpense_E1033A8C53383FAA338A0256633F9350_label_en-US" xlink:label="lab_us-gaap_SellingGeneralAndAdministrativeExpense_E1033A8C53383FAA338A0256633F9350" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Selling, General and Administrative Expense</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_SellingGeneralAndAdministrativeExpense" xlink:label="loc_us-gaap_SellingGeneralAndAdministrativeExpense_E1033A8C53383FAA338A0256633F9350" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SellingGeneralAndAdministrativeExpense_E1033A8C53383FAA338A0256633F9350" xlink:to="lab_us-gaap_SellingGeneralAndAdministrativeExpense_E1033A8C53383FAA338A0256633F9350" xlink:type="arc" />
    <link:label id="lab_us-gaap_ResearchAndDevelopmentExpense_A8197B12259E20CE52280256633FCA8B_terseLabel_en-US" xlink:label="lab_us-gaap_ResearchAndDevelopmentExpense_A8197B12259E20CE52280256633FCA8B" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Research and development expenses</link:label>
    <link:label id="lab_us-gaap_ResearchAndDevelopmentExpense_A8197B12259E20CE52280256633FCA8B_label_en-US" xlink:label="lab_us-gaap_ResearchAndDevelopmentExpense_A8197B12259E20CE52280256633FCA8B" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Research and Development Expense</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ResearchAndDevelopmentExpense" xlink:label="loc_us-gaap_ResearchAndDevelopmentExpense_A8197B12259E20CE52280256633FCA8B" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ResearchAndDevelopmentExpense_A8197B12259E20CE52280256633FCA8B" xlink:to="lab_us-gaap_ResearchAndDevelopmentExpense_A8197B12259E20CE52280256633FCA8B" xlink:type="arc" />
    <link:label id="lab_us-gaap_DepreciationAndAmortization_DF151936B06A6319D7F30256633F1BF3_terseLabel_en-US" xlink:label="lab_us-gaap_DepreciationAndAmortization_DF151936B06A6319D7F30256633F1BF3" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Provision for depreciation and amortization</link:label>
    <link:label id="lab_us-gaap_DepreciationAndAmortization_DF151936B06A6319D7F30256633F1BF3_label_en-US" xlink:label="lab_us-gaap_DepreciationAndAmortization_DF151936B06A6319D7F30256633F1BF3" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Depreciation, Depletion and Amortization, Nonproduction</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DepreciationAndAmortization" xlink:label="loc_us-gaap_DepreciationAndAmortization_DF151936B06A6319D7F30256633F1BF3" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DepreciationAndAmortization_DF151936B06A6319D7F30256633F1BF3" xlink:to="lab_us-gaap_DepreciationAndAmortization_DF151936B06A6319D7F30256633F1BF3" xlink:type="arc" />
    <link:label id="lab_us-gaap_GoodwillImpairmentLoss_B4E25FD621203F0A0BCE0256633FF47A_terseLabel_en-US" xlink:label="lab_us-gaap_GoodwillImpairmentLoss_B4E25FD621203F0A0BCE0256633FF47A" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Impairment of goodwill (A and O)</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_GoodwillImpairmentLoss" xlink:label="loc_us-gaap_GoodwillImpairmentLoss_B4E25FD621203F0A0BCE0256633FF47A" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_GoodwillImpairmentLoss_B4E25FD621203F0A0BCE0256633FF47A" xlink:to="lab_us-gaap_GoodwillImpairmentLoss_B4E25FD621203F0A0BCE0256633FF47A" xlink:type="arc" />
    <link:label id="lab_us-gaap_RestructuringCharges_055CC9A3C0DDBBF275C80256633F793F_terseLabel_en-US" xlink:label="lab_us-gaap_RestructuringCharges_055CC9A3C0DDBBF275C80256633F793F" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Restructuring and other charges (D)</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RestructuringCharges" xlink:label="loc_us-gaap_RestructuringCharges_055CC9A3C0DDBBF275C80256633F793F" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RestructuringCharges_055CC9A3C0DDBBF275C80256633F793F" xlink:to="lab_us-gaap_RestructuringCharges_055CC9A3C0DDBBF275C80256633F793F" xlink:type="arc" />
    <link:label id="lab_us-gaap_InterestExpense_D9B3889247D20F3B75A50256633FB792_terseLabel_en-US" xlink:label="lab_us-gaap_InterestExpense_D9B3889247D20F3B75A50256633FB792" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Interest expense (E)</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_InterestExpense" xlink:label="loc_us-gaap_InterestExpense_D9B3889247D20F3B75A50256633FB792" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_InterestExpense_D9B3889247D20F3B75A50256633FB792" xlink:to="lab_us-gaap_InterestExpense_D9B3889247D20F3B75A50256633FB792" xlink:type="arc" />
    <link:label id="lab_us-gaap_NonoperatingIncomeExpense_9B60463EF339AF4E354F0256633F6951_verboseLabel_en-US" xlink:label="lab_us-gaap_NonoperatingIncomeExpense_9B60463EF339AF4E354F0256633F6951" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Other expense (income), net (F)</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_NonoperatingIncomeExpense" xlink:label="loc_us-gaap_NonoperatingIncomeExpense_9B60463EF339AF4E354F0256633F6951" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_NonoperatingIncomeExpense_9B60463EF339AF4E354F0256633F6951" xlink:to="lab_us-gaap_NonoperatingIncomeExpense_9B60463EF339AF4E354F0256633F6951" xlink:type="arc" />
    <link:label id="lab_us-gaap_IncomeTaxExpenseBenefit_2AC5D45CA8FE7E9C8B0A0256633F25D0_verboseLabel_en-US" xlink:label="lab_us-gaap_IncomeTaxExpenseBenefit_2AC5D45CA8FE7E9C8B0A0256633F25D0" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Provision for income taxes (H)</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_IncomeTaxExpenseBenefit" xlink:label="loc_us-gaap_IncomeTaxExpenseBenefit_2AC5D45CA8FE7E9C8B0A0256633F25D0" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncomeTaxExpenseBenefit_2AC5D45CA8FE7E9C8B0A0256633F25D0" xlink:to="lab_us-gaap_IncomeTaxExpenseBenefit_2AC5D45CA8FE7E9C8B0A0256633F25D0" xlink:type="arc" />
    <link:label id="lab_us-gaap_IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest_D33D24954C7C2A07CCD30256633F4D61_totalLabel_en-US" xlink:label="lab_us-gaap_IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest_D33D24954C7C2A07CCD30256633F4D61" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Income (loss) from continuing operations after income taxes</link:label>
    <link:label id="lab_us-gaap_IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest_D33D24954C7C2A07CCD30256633F4D61_label_en-US" xlink:label="lab_us-gaap_IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest_D33D24954C7C2A07CCD30256633F4D61" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Income (Loss) from Continuing Operations, Net of Tax, Including Portion Attributable to Noncontrolling Interest</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest" xlink:label="loc_us-gaap_IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest_D33D24954C7C2A07CCD30256633F4D61" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest_D33D24954C7C2A07CCD30256633F4D61" xlink:to="lab_us-gaap_IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest_D33D24954C7C2A07CCD30256633F4D61" xlink:type="arc" />
    <link:label id="lab_us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTax_1FB3585D2BDCEA81FBE40256633FED8B_verboseLabel_en-US" xlink:label="lab_us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTax_1FB3585D2BDCEA81FBE40256633FED8B" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Income from discontinued operations after income taxes (V)</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTax" xlink:label="loc_us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTax_1FB3585D2BDCEA81FBE40256633FED8B" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTax_1FB3585D2BDCEA81FBE40256633FED8B" xlink:to="lab_us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTax_1FB3585D2BDCEA81FBE40256633FED8B" xlink:type="arc" />
    <link:label id="lab_us-gaap_ProfitLoss_B01CA6BA5F8FF45F64180256633FEBC2_totalLabel_en-US" xlink:label="lab_us-gaap_ProfitLoss_B01CA6BA5F8FF45F64180256633FEBC2" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Net income (loss)</link:label>
    <link:label id="lab_us-gaap_ProfitLoss_B01CA6BA5F8FF45F64180256633FEBC2_label_en-US" xlink:label="lab_us-gaap_ProfitLoss_B01CA6BA5F8FF45F64180256633FEBC2" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Net Income (Loss), Including Portion Attributable to Noncontrolling Interest</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ProfitLoss" xlink:label="loc_us-gaap_ProfitLoss_B01CA6BA5F8FF45F64180256633FEBC2" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ProfitLoss_B01CA6BA5F8FF45F64180256633FEBC2" xlink:to="lab_us-gaap_ProfitLoss_B01CA6BA5F8FF45F64180256633FEBC2" xlink:type="arc" />
    <link:label id="lab_us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToNoncontrollingInterest_C889B9381350D3EBBA0F0256633F69B9_verboseLabel_en-US" xlink:label="lab_us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToNoncontrollingInterest_C889B9381350D3EBBA0F0256633F69B9" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Less: Net income from discontinued operations attributable to noncontrolling interests (V)</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToNoncontrollingInterest" xlink:label="loc_us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToNoncontrollingInterest_C889B9381350D3EBBA0F0256633F69B9" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToNoncontrollingInterest_C889B9381350D3EBBA0F0256633F69B9" xlink:to="lab_us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToNoncontrollingInterest_C889B9381350D3EBBA0F0256633F69B9" xlink:type="arc" />
    <link:label id="lab_us-gaap_NetIncomeLoss_C99792C26C1CCF0772E00256633F0FA5_totalLabel_en-US" xlink:label="lab_us-gaap_NetIncomeLoss_C99792C26C1CCF0772E00256633F0FA5" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Net income (loss) Attributable to Arconic</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_NetIncomeLoss" xlink:label="loc_us-gaap_NetIncomeLoss_C99792C26C1CCF0772E00256633F0FA5" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_NetIncomeLoss_C99792C26C1CCF0772E00256633F0FA5" xlink:to="lab_us-gaap_NetIncomeLoss_C99792C26C1CCF0772E00256633F0FA5" xlink:type="arc" />
    <link:label id="lab_us-gaap_NetIncomeLossAvailableToCommonStockholdersDiluted_8E1725B89F523DF24AB70263C7F33C41_terseLabel_en-US" xlink:label="lab_us-gaap_NetIncomeLossAvailableToCommonStockholdersDiluted_8E1725B89F523DF24AB70263C7F33C41" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Net income (loss)</link:label>
    <link:label id="lab_us-gaap_NetIncomeLossAvailableToCommonStockholdersDiluted_8E1725B89F523DF24AB70263C7F33C41_label_en-US" xlink:label="lab_us-gaap_NetIncomeLossAvailableToCommonStockholdersDiluted_8E1725B89F523DF24AB70263C7F33C41" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Net Income (Loss) Available to Common Stockholders, Diluted</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_NetIncomeLossAvailableToCommonStockholdersDiluted" xlink:label="loc_us-gaap_NetIncomeLossAvailableToCommonStockholdersDiluted_8E1725B89F523DF24AB70263C7F33C41" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_NetIncomeLossAvailableToCommonStockholdersDiluted_8E1725B89F523DF24AB70263C7F33C41" xlink:to="lab_us-gaap_NetIncomeLossAvailableToCommonStockholdersDiluted_8E1725B89F523DF24AB70263C7F33C41" xlink:type="arc" />
    <link:label id="lab_us-gaap_IncomeAmountsAttributableToReportingEntityDisclosuresAbstract_41CE7C724C0E1832D1220256633FBFB1_terseLabel_en-US" xlink:label="lab_us-gaap_IncomeAmountsAttributableToReportingEntityDisclosuresAbstract_41CE7C724C0E1832D1220256633FBFB1" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Amounts Attributable to Arconic Common Shareholders (J):</link:label>
    <link:label id="lab_us-gaap_IncomeAmountsAttributableToReportingEntityDisclosuresAbstract_41CE7C724C0E1832D1220256633FBFB1_label_en-US" xlink:label="lab_us-gaap_IncomeAmountsAttributableToReportingEntityDisclosuresAbstract_41CE7C724C0E1832D1220256633FBFB1" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Income Amounts Attributable to Parent, Disclosures [Abstract]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_IncomeAmountsAttributableToReportingEntityDisclosuresAbstract" xlink:label="loc_us-gaap_IncomeAmountsAttributableToReportingEntityDisclosuresAbstract_41CE7C724C0E1832D1220256633FBFB1" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncomeAmountsAttributableToReportingEntityDisclosuresAbstract_41CE7C724C0E1832D1220256633FBFB1" xlink:to="lab_us-gaap_IncomeAmountsAttributableToReportingEntityDisclosuresAbstract_41CE7C724C0E1832D1220256633FBFB1" xlink:type="arc" />
    <link:label id="lab_us-gaap_EarningsPerShareBasicAbstract_579E590A068A97CC94B40256633F0B6E_verboseLabel_en-US" xlink:label="lab_us-gaap_EarningsPerShareBasicAbstract_579E590A068A97CC94B40256633F0B6E" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Earnings (loss) per share&#8212;basic:</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_EarningsPerShareBasicAbstract" xlink:label="loc_us-gaap_EarningsPerShareBasicAbstract_579E590A068A97CC94B40256633F0B6E" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_EarningsPerShareBasicAbstract_579E590A068A97CC94B40256633F0B6E" xlink:to="lab_us-gaap_EarningsPerShareBasicAbstract_579E590A068A97CC94B40256633F0B6E" xlink:type="arc" />
    <link:label id="lab_us-gaap_IncomeLossFromContinuingOperationsPerBasicShare_069174A76775D7E0BF670256633FBE5F_terseLabel_en-US" xlink:label="lab_us-gaap_IncomeLossFromContinuingOperationsPerBasicShare_069174A76775D7E0BF670256633FBE5F" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Continuing operations (in usd per share)</link:label>
    <link:label id="lab_us-gaap_IncomeLossFromContinuingOperationsPerBasicShare_069174A76775D7E0BF670256633FBE5F_label_en-US" xlink:label="lab_us-gaap_IncomeLossFromContinuingOperationsPerBasicShare_069174A76775D7E0BF670256633FBE5F" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Income (Loss) from Continuing Operations, Per Basic Share</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_IncomeLossFromContinuingOperationsPerBasicShare" xlink:label="loc_us-gaap_IncomeLossFromContinuingOperationsPerBasicShare_069174A76775D7E0BF670256633FBE5F" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncomeLossFromContinuingOperationsPerBasicShare_069174A76775D7E0BF670256633FBE5F" xlink:to="lab_us-gaap_IncomeLossFromContinuingOperationsPerBasicShare_069174A76775D7E0BF670256633FBE5F" xlink:type="arc" />
    <link:label id="lab_us-gaap_DiscontinuedOperationIncomeLossFromDiscontinuedOperationNetOfTaxPerBasicShare_2F54B44EBE72A60ABB1A0256633F854F_terseLabel_en-US" xlink:label="lab_us-gaap_DiscontinuedOperationIncomeLossFromDiscontinuedOperationNetOfTaxPerBasicShare_2F54B44EBE72A60ABB1A0256633F854F" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Discontinued operations (in usd per share)</link:label>
    <link:label id="lab_us-gaap_DiscontinuedOperationIncomeLossFromDiscontinuedOperationNetOfTaxPerBasicShare_2F54B44EBE72A60ABB1A0256633F854F_label_en-US" xlink:label="lab_us-gaap_DiscontinuedOperationIncomeLossFromDiscontinuedOperationNetOfTaxPerBasicShare_2F54B44EBE72A60ABB1A0256633F854F" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Discontinued Operation, Income (Loss) from Discontinued Operation, Net of Tax, Per Basic Share</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DiscontinuedOperationIncomeLossFromDiscontinuedOperationNetOfTaxPerBasicShare" xlink:label="loc_us-gaap_DiscontinuedOperationIncomeLossFromDiscontinuedOperationNetOfTaxPerBasicShare_2F54B44EBE72A60ABB1A0256633F854F" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DiscontinuedOperationIncomeLossFromDiscontinuedOperationNetOfTaxPerBasicShare_2F54B44EBE72A60ABB1A0256633F854F" xlink:to="lab_us-gaap_DiscontinuedOperationIncomeLossFromDiscontinuedOperationNetOfTaxPerBasicShare_2F54B44EBE72A60ABB1A0256633F854F" xlink:type="arc" />
    <link:label id="lab_us-gaap_EarningsPerShareDilutedAbstract_375BC66E5A2D2108CF680256633FF0EC_verboseLabel_en-US" xlink:label="lab_us-gaap_EarningsPerShareDilutedAbstract_375BC66E5A2D2108CF680256633FF0EC" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Earnings (loss) per share&#8212;diluted</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_EarningsPerShareDilutedAbstract" xlink:label="loc_us-gaap_EarningsPerShareDilutedAbstract_375BC66E5A2D2108CF680256633FF0EC" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_EarningsPerShareDilutedAbstract_375BC66E5A2D2108CF680256633FF0EC" xlink:to="lab_us-gaap_EarningsPerShareDilutedAbstract_375BC66E5A2D2108CF680256633FF0EC" xlink:type="arc" />
    <link:label id="lab_us-gaap_IncomeLossFromContinuingOperationsPerDilutedShare_4B134A7358FCAC92382D0256633FA5C2_terseLabel_en-US" xlink:label="lab_us-gaap_IncomeLossFromContinuingOperationsPerDilutedShare_4B134A7358FCAC92382D0256633FA5C2" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Continuing operations (in usd per share)</link:label>
    <link:label id="lab_us-gaap_IncomeLossFromContinuingOperationsPerDilutedShare_4B134A7358FCAC92382D0256633FA5C2_label_en-US" xlink:label="lab_us-gaap_IncomeLossFromContinuingOperationsPerDilutedShare_4B134A7358FCAC92382D0256633FA5C2" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Income (Loss) from Continuing Operations, Per Diluted Share</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_IncomeLossFromContinuingOperationsPerDilutedShare" xlink:label="loc_us-gaap_IncomeLossFromContinuingOperationsPerDilutedShare_4B134A7358FCAC92382D0256633FA5C2" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncomeLossFromContinuingOperationsPerDilutedShare_4B134A7358FCAC92382D0256633FA5C2" xlink:to="lab_us-gaap_IncomeLossFromContinuingOperationsPerDilutedShare_4B134A7358FCAC92382D0256633FA5C2" xlink:type="arc" />
    <link:label id="lab_us-gaap_DiscontinuedOperationIncomeLossFromDiscontinuedOperationNetOfTaxPerDilutedShare_7D775305866BD4A5A3610256633F9A9B_terseLabel_en-US" xlink:label="lab_us-gaap_DiscontinuedOperationIncomeLossFromDiscontinuedOperationNetOfTaxPerDilutedShare_7D775305866BD4A5A3610256633F9A9B" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Discontinued operations (in usd per share)</link:label>
    <link:label id="lab_us-gaap_DiscontinuedOperationIncomeLossFromDiscontinuedOperationNetOfTaxPerDilutedShare_7D775305866BD4A5A3610256633F9A9B_label_en-US" xlink:label="lab_us-gaap_DiscontinuedOperationIncomeLossFromDiscontinuedOperationNetOfTaxPerDilutedShare_7D775305866BD4A5A3610256633F9A9B" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Discontinued Operation, Income (Loss) from Discontinued Operation, Net of Tax, Per Diluted Share</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DiscontinuedOperationIncomeLossFromDiscontinuedOperationNetOfTaxPerDilutedShare" xlink:label="loc_us-gaap_DiscontinuedOperationIncomeLossFromDiscontinuedOperationNetOfTaxPerDilutedShare_7D775305866BD4A5A3610256633F9A9B" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DiscontinuedOperationIncomeLossFromDiscontinuedOperationNetOfTaxPerDilutedShare_7D775305866BD4A5A3610256633F9A9B" xlink:to="lab_us-gaap_DiscontinuedOperationIncomeLossFromDiscontinuedOperationNetOfTaxPerDilutedShare_7D775305866BD4A5A3610256633F9A9B" xlink:type="arc" />
    <link:label id="lab_us-gaap_StockholdersEquityNoteDisclosureTextBlock_2198FB44ED27D6687F757C362E3B19D1_terseLabel_en-US" xlink:label="lab_us-gaap_StockholdersEquityNoteDisclosureTextBlock_2198FB44ED27D6687F757C362E3B19D1" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Preferred and Common Stock</link:label>
    <link:label id="lab_us-gaap_StockholdersEquityNoteDisclosureTextBlock_2198FB44ED27D6687F757C362E3B19D1_label_en-US" xlink:label="lab_us-gaap_StockholdersEquityNoteDisclosureTextBlock_2198FB44ED27D6687F757C362E3B19D1" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Stockholders' Equity Note Disclosure [Text Block]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_StockholdersEquityNoteDisclosureTextBlock" xlink:label="loc_us-gaap_StockholdersEquityNoteDisclosureTextBlock_2198FB44ED27D6687F757C362E3B19D1" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_StockholdersEquityNoteDisclosureTextBlock_2198FB44ED27D6687F757C362E3B19D1" xlink:to="lab_us-gaap_StockholdersEquityNoteDisclosureTextBlock_2198FB44ED27D6687F757C362E3B19D1" xlink:type="arc" />
    <link:label id="lab_us-gaap_PayablesAndAccrualsAbstract_62B3734250D2607EA688E244A9665CB6_label_en-US" xlink:label="lab_us-gaap_PayablesAndAccrualsAbstract_62B3734250D2607EA688E244A9665CB6" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Payables and Accruals [Abstract]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PayablesAndAccrualsAbstract" xlink:label="loc_us-gaap_PayablesAndAccrualsAbstract_62B3734250D2607EA688E244A9665CB6" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PayablesAndAccrualsAbstract_62B3734250D2607EA688E244A9665CB6" xlink:to="lab_us-gaap_PayablesAndAccrualsAbstract_62B3734250D2607EA688E244A9665CB6" xlink:type="arc" />
    <link:label id="lab_arnc_ScheduleOfOtherNoncurrentLiabilitiesAndDeferredCreditsTableTextBlock_36082714CE14CEF18602E244A9663B58_terseLabel_en-US" xlink:label="lab_arnc_ScheduleOfOtherNoncurrentLiabilitiesAndDeferredCreditsTableTextBlock_36082714CE14CEF18602E244A9663B58" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Schedule of Other Noncurrent Liabilities and Deferred Credits</link:label>
    <link:label id="lab_arnc_ScheduleOfOtherNoncurrentLiabilitiesAndDeferredCreditsTableTextBlock_36082714CE14CEF18602E244A9663B58_label_en-US" xlink:label="lab_arnc_ScheduleOfOtherNoncurrentLiabilitiesAndDeferredCreditsTableTextBlock_36082714CE14CEF18602E244A9663B58" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Schedule Of Other Noncurrent Liabilities And Deferred Credits Table [Text Block]</link:label>
    <link:label id="lab_arnc_ScheduleOfOtherNoncurrentLiabilitiesAndDeferredCreditsTableTextBlock_36082714CE14CEF18602E244A9663B58_documentation_en-US" xlink:label="lab_arnc_ScheduleOfOtherNoncurrentLiabilitiesAndDeferredCreditsTableTextBlock_36082714CE14CEF18602E244A9663B58" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Schedule of other noncurrent liabilities and deferred credits.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_ScheduleOfOtherNoncurrentLiabilitiesAndDeferredCreditsTableTextBlock" xlink:label="loc_arnc_ScheduleOfOtherNoncurrentLiabilitiesAndDeferredCreditsTableTextBlock_36082714CE14CEF18602E244A9663B58" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_ScheduleOfOtherNoncurrentLiabilitiesAndDeferredCreditsTableTextBlock_36082714CE14CEF18602E244A9663B58" xlink:to="lab_arnc_ScheduleOfOtherNoncurrentLiabilitiesAndDeferredCreditsTableTextBlock_36082714CE14CEF18602E244A9663B58" xlink:type="arc" />
    <link:label id="lab_us-gaap_CommercialPaperMember_DE4F36D21C94462940DCE244A96A1E27_terseLabel_en-US" xlink:label="lab_us-gaap_CommercialPaperMember_DE4F36D21C94462940DCE244A96A1E27" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Commercial Paper</link:label>
    <link:label id="lab_us-gaap_CommercialPaperMember_DE4F36D21C94462940DCE244A96A1E27_label_en-US" xlink:label="lab_us-gaap_CommercialPaperMember_DE4F36D21C94462940DCE244A96A1E27" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Commercial Paper [Member]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_CommercialPaperMember" xlink:label="loc_us-gaap_CommercialPaperMember_DE4F36D21C94462940DCE244A96A1E27" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CommercialPaperMember_DE4F36D21C94462940DCE244A96A1E27" xlink:to="lab_us-gaap_CommercialPaperMember_DE4F36D21C94462940DCE244A96A1E27" xlink:type="arc" />
    <link:label id="lab_arnc_AverageOutstandingCommercialPaper_CAD3219483E41B9AD868E244A96AA2AB_terseLabel_en-US" xlink:label="lab_arnc_AverageOutstandingCommercialPaper_CAD3219483E41B9AD868E244A96AA2AB" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Average outstanding commercial paper</link:label>
    <link:label id="lab_arnc_AverageOutstandingCommercialPaper_CAD3219483E41B9AD868E244A96AA2AB_label_en-US" xlink:label="lab_arnc_AverageOutstandingCommercialPaper_CAD3219483E41B9AD868E244A96AA2AB" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Average Outstanding Commercial Paper</link:label>
    <link:label id="lab_arnc_AverageOutstandingCommercialPaper_CAD3219483E41B9AD868E244A96AA2AB_documentation_en-US" xlink:label="lab_arnc_AverageOutstandingCommercialPaper_CAD3219483E41B9AD868E244A96AA2AB" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Average outstanding commercial paper.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_AverageOutstandingCommercialPaper" xlink:label="loc_arnc_AverageOutstandingCommercialPaper_CAD3219483E41B9AD868E244A96AA2AB" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_AverageOutstandingCommercialPaper_CAD3219483E41B9AD868E244A96AA2AB" xlink:to="lab_arnc_AverageOutstandingCommercialPaper_CAD3219483E41B9AD868E244A96AA2AB" xlink:type="arc" />
    <link:label id="lab_us-gaap_DebtInstrumentTerm_62CC0317BDA470E19483E244A96A5991_terseLabel_en-US" xlink:label="lab_us-gaap_DebtInstrumentTerm_62CC0317BDA470E19483E244A96A5991" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Debt instrument maturity date, description</link:label>
    <link:label id="lab_us-gaap_DebtInstrumentTerm_62CC0317BDA470E19483E244A96A5991_label_en-US" xlink:label="lab_us-gaap_DebtInstrumentTerm_62CC0317BDA470E19483E244A96A5991" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Debt Instrument, Term</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DebtInstrumentTerm" xlink:label="loc_us-gaap_DebtInstrumentTerm_62CC0317BDA470E19483E244A96A5991" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DebtInstrumentTerm_62CC0317BDA470E19483E244A96A5991" xlink:to="lab_us-gaap_DebtInstrumentTerm_62CC0317BDA470E19483E244A96A5991" xlink:type="arc" />
    <link:label id="lab_us-gaap_DebtWeightedAverageInterestRate_44AB2FE55444B2201860E244A96A309F_terseLabel_en-US" xlink:label="lab_us-gaap_DebtWeightedAverageInterestRate_44AB2FE55444B2201860E244A96A309F" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Long-term interest rate</link:label>
    <link:label id="lab_us-gaap_DebtWeightedAverageInterestRate_44AB2FE55444B2201860E244A96A309F_label_en-US" xlink:label="lab_us-gaap_DebtWeightedAverageInterestRate_44AB2FE55444B2201860E244A96A309F" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Debt, Weighted Average Interest Rate</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DebtWeightedAverageInterestRate" xlink:label="loc_us-gaap_DebtWeightedAverageInterestRate_44AB2FE55444B2201860E244A96A309F" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DebtWeightedAverageInterestRate_44AB2FE55444B2201860E244A96A309F" xlink:to="lab_us-gaap_DebtWeightedAverageInterestRate_44AB2FE55444B2201860E244A96A309F" xlink:type="arc" />
    <link:label id="lab_us-gaap_EarningsPerShareAbstract_286A0719F734318CAEB59C2314EDA9DA_label_en-US" xlink:label="lab_us-gaap_EarningsPerShareAbstract_286A0719F734318CAEB59C2314EDA9DA" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Earnings Per Share [Abstract]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_EarningsPerShareAbstract" xlink:label="loc_us-gaap_EarningsPerShareAbstract_286A0719F734318CAEB59C2314EDA9DA" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_EarningsPerShareAbstract_286A0719F734318CAEB59C2314EDA9DA" xlink:to="lab_us-gaap_EarningsPerShareAbstract_286A0719F734318CAEB59C2314EDA9DA" xlink:type="arc" />
    <link:label id="lab_us-gaap_IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest_44D10EB1DE905981C1239C2314ED13C4_verboseLabel_en-US" xlink:label="lab_us-gaap_IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest_44D10EB1DE905981C1239C2314ED13C4" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Net income (loss) from continuing operations attributable to Arconic</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest" xlink:label="loc_us-gaap_IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest_44D10EB1DE905981C1239C2314ED13C4" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest_44D10EB1DE905981C1239C2314ED13C4" xlink:to="lab_us-gaap_IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest_44D10EB1DE905981C1239C2314ED13C4" xlink:type="arc" />
    <link:label id="lab_us-gaap_PreferredStockDividendsAndOtherAdjustments_76358472BB13B28CDC6A9C2314ED4B03_negatedTerseLabel_en-US" xlink:label="lab_us-gaap_PreferredStockDividendsAndOtherAdjustments_76358472BB13B28CDC6A9C2314ED4B03" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:type="resource" xml:lang="en-US">Less: preferred stock dividends declared</link:label>
    <link:label id="lab_us-gaap_PreferredStockDividendsAndOtherAdjustments_76358472BB13B28CDC6A9C2314ED4B03_label_en-US" xlink:label="lab_us-gaap_PreferredStockDividendsAndOtherAdjustments_76358472BB13B28CDC6A9C2314ED4B03" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Preferred Stock Dividends and Other Adjustments</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PreferredStockDividendsAndOtherAdjustments" xlink:label="loc_us-gaap_PreferredStockDividendsAndOtherAdjustments_76358472BB13B28CDC6A9C2314ED4B03" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PreferredStockDividendsAndOtherAdjustments_76358472BB13B28CDC6A9C2314ED4B03" xlink:to="lab_us-gaap_PreferredStockDividendsAndOtherAdjustments_76358472BB13B28CDC6A9C2314ED4B03" xlink:type="arc" />
    <link:label id="lab_us-gaap_IncomeLossFromContinuingOperations_E632C07714328D0D268D9C2314EEA7F6_totalLabel_en-US" xlink:label="lab_us-gaap_IncomeLossFromContinuingOperations_E632C07714328D0D268D9C2314EEA7F6" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Income (loss) from continuing operations available to Arconic common shareholders</link:label>
    <link:label id="lab_us-gaap_IncomeLossFromContinuingOperations_E632C07714328D0D268D9C2314EEA7F6_label_en-US" xlink:label="lab_us-gaap_IncomeLossFromContinuingOperations_E632C07714328D0D268D9C2314EEA7F6" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Income (Loss) from Continuing Operations, Net of Tax, Attributable to Parent</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_IncomeLossFromContinuingOperations" xlink:label="loc_us-gaap_IncomeLossFromContinuingOperations_E632C07714328D0D268D9C2314EEA7F6" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncomeLossFromContinuingOperations_E632C07714328D0D268D9C2314EEA7F6" xlink:to="lab_us-gaap_IncomeLossFromContinuingOperations_E632C07714328D0D268D9C2314EEA7F6" xlink:type="arc" />
    <link:label id="lab_us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity_04E60EC2FD50AFF5CC5B9C2314EEA961_verboseLabel_en-US" xlink:label="lab_us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity_04E60EC2FD50AFF5CC5B9C2314EEA961" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Income (loss) from discontinued operations after income taxes and noncontrolling interests</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity" xlink:label="loc_us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity_04E60EC2FD50AFF5CC5B9C2314EEA961" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity_04E60EC2FD50AFF5CC5B9C2314EEA961" xlink:to="lab_us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity_04E60EC2FD50AFF5CC5B9C2314EEA961" xlink:type="arc" />
    <link:label id="lab_us-gaap_NetIncomeLossAvailableToCommonStockholdersBasic_E2BC793DDBD87F1998909C2314EE6697_totalLabel_en-US" xlink:label="lab_us-gaap_NetIncomeLossAvailableToCommonStockholdersBasic_E2BC793DDBD87F1998909C2314EE6697" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Net income (loss) available to Arconic common shareholders&#8212;basic</link:label>
    <link:label id="lab_us-gaap_NetIncomeLossAvailableToCommonStockholdersBasic_E2BC793DDBD87F1998909C2314EE6697_label_en-US" xlink:label="lab_us-gaap_NetIncomeLossAvailableToCommonStockholdersBasic_E2BC793DDBD87F1998909C2314EE6697" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Net Income (Loss) Available to Common Stockholders, Basic</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_NetIncomeLossAvailableToCommonStockholdersBasic" xlink:label="loc_us-gaap_NetIncomeLossAvailableToCommonStockholdersBasic_E2BC793DDBD87F1998909C2314EE6697" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_NetIncomeLossAvailableToCommonStockholdersBasic_E2BC793DDBD87F1998909C2314EE6697" xlink:to="lab_us-gaap_NetIncomeLossAvailableToCommonStockholdersBasic_E2BC793DDBD87F1998909C2314EE6697" xlink:type="arc" />
    <link:label id="lab_us-gaap_InterestOnConvertibleDebtNetOfTax_D86B40C94931474CDBDC9C2314EEA892_terseLabel_en-US" xlink:label="lab_us-gaap_InterestOnConvertibleDebtNetOfTax_D86B40C94931474CDBDC9C2314EEA892" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Add: interest expense related to convertible notes</link:label>
    <link:label id="lab_us-gaap_InterestOnConvertibleDebtNetOfTax_D86B40C94931474CDBDC9C2314EEA892_label_en-US" xlink:label="lab_us-gaap_InterestOnConvertibleDebtNetOfTax_D86B40C94931474CDBDC9C2314EEA892" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Interest on Convertible Debt, Net of Tax</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_InterestOnConvertibleDebtNetOfTax" xlink:label="loc_us-gaap_InterestOnConvertibleDebtNetOfTax_D86B40C94931474CDBDC9C2314EEA892" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_InterestOnConvertibleDebtNetOfTax_D86B40C94931474CDBDC9C2314EEA892" xlink:to="lab_us-gaap_InterestOnConvertibleDebtNetOfTax_D86B40C94931474CDBDC9C2314EEA892" xlink:type="arc" />
    <link:label id="lab_us-gaap_NetIncomeLossAvailableToCommonStockholdersDiluted_20A12DBED2773F0F3D739C2314EE3AC5_totalLabel_en-US" xlink:label="lab_us-gaap_NetIncomeLossAvailableToCommonStockholdersDiluted_20A12DBED2773F0F3D739C2314EE3AC5" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Net income (loss) available to Arconic common shareholders - diluted</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_NetIncomeLossAvailableToCommonStockholdersDiluted" xlink:label="loc_us-gaap_NetIncomeLossAvailableToCommonStockholdersDiluted_20A12DBED2773F0F3D739C2314EE3AC5" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_NetIncomeLossAvailableToCommonStockholdersDiluted_20A12DBED2773F0F3D739C2314EE3AC5" xlink:to="lab_us-gaap_NetIncomeLossAvailableToCommonStockholdersDiluted_20A12DBED2773F0F3D739C2314EE3AC5" xlink:type="arc" />
    <link:label id="lab_us-gaap_WeightedAverageNumberOfSharesOutstandingBasic_B982835D4C474C5F97F19C2314EE2F4E_terseLabel_en-US" xlink:label="lab_us-gaap_WeightedAverageNumberOfSharesOutstandingBasic_B982835D4C474C5F97F19C2314EE2F4E" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Average shares outstanding - basic</link:label>
    <link:label id="lab_us-gaap_WeightedAverageNumberOfSharesOutstandingBasic_B982835D4C474C5F97F19C2314EE2F4E_label_en-US" xlink:label="lab_us-gaap_WeightedAverageNumberOfSharesOutstandingBasic_B982835D4C474C5F97F19C2314EE2F4E" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Weighted Average Number of Shares Outstanding, Basic</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_WeightedAverageNumberOfSharesOutstandingBasic" xlink:label="loc_us-gaap_WeightedAverageNumberOfSharesOutstandingBasic_B982835D4C474C5F97F19C2314EE2F4E" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_WeightedAverageNumberOfSharesOutstandingBasic_B982835D4C474C5F97F19C2314EE2F4E" xlink:to="lab_us-gaap_WeightedAverageNumberOfSharesOutstandingBasic_B982835D4C474C5F97F19C2314EE2F4E" xlink:type="arc" />
    <link:label id="lab_us-gaap_DilutiveSecuritiesAbstract_0F015828228C4F4949479C2314EFCE9C_terseLabel_en-US" xlink:label="lab_us-gaap_DilutiveSecuritiesAbstract_0F015828228C4F4949479C2314EFCE9C" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Effect of dilutive securities:</link:label>
    <link:label id="lab_us-gaap_DilutiveSecuritiesAbstract_0F015828228C4F4949479C2314EFCE9C_label_en-US" xlink:label="lab_us-gaap_DilutiveSecuritiesAbstract_0F015828228C4F4949479C2314EFCE9C" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Dilutive Securities, Effect on Basic Earnings Per Share [Abstract]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DilutiveSecuritiesAbstract" xlink:label="loc_us-gaap_DilutiveSecuritiesAbstract_0F015828228C4F4949479C2314EFCE9C" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DilutiveSecuritiesAbstract_0F015828228C4F4949479C2314EFCE9C" xlink:to="lab_us-gaap_DilutiveSecuritiesAbstract_0F015828228C4F4949479C2314EFCE9C" xlink:type="arc" />
    <link:label id="lab_us-gaap_IncrementalCommonSharesAttributableToShareBasedPaymentArrangements_E2857809F791EAB67B559C2314EF714C_terseLabel_en-US" xlink:label="lab_us-gaap_IncrementalCommonSharesAttributableToShareBasedPaymentArrangements_E2857809F791EAB67B559C2314EF714C" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Stock options</link:label>
    <link:label id="lab_us-gaap_IncrementalCommonSharesAttributableToShareBasedPaymentArrangements_E2857809F791EAB67B559C2314EF714C_label_en-US" xlink:label="lab_us-gaap_IncrementalCommonSharesAttributableToShareBasedPaymentArrangements_E2857809F791EAB67B559C2314EF714C" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Incremental Common Shares Attributable to Dilutive Effect of Share-based Payment Arrangements</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_IncrementalCommonSharesAttributableToShareBasedPaymentArrangements" xlink:label="loc_us-gaap_IncrementalCommonSharesAttributableToShareBasedPaymentArrangements_E2857809F791EAB67B559C2314EF714C" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncrementalCommonSharesAttributableToShareBasedPaymentArrangements_E2857809F791EAB67B559C2314EF714C" xlink:to="lab_us-gaap_IncrementalCommonSharesAttributableToShareBasedPaymentArrangements_E2857809F791EAB67B559C2314EF714C" xlink:type="arc" />
    <link:label id="lab_us-gaap_IncrementalCommonSharesAttributableToNonvestedSharesWithForfeitableDividends_18D3ADB610FD59307EE49C2314EFF948_terseLabel_en-US" xlink:label="lab_us-gaap_IncrementalCommonSharesAttributableToNonvestedSharesWithForfeitableDividends_18D3ADB610FD59307EE49C2314EFF948" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Stock and performance awards</link:label>
    <link:label id="lab_us-gaap_IncrementalCommonSharesAttributableToNonvestedSharesWithForfeitableDividends_18D3ADB610FD59307EE49C2314EFF948_label_en-US" xlink:label="lab_us-gaap_IncrementalCommonSharesAttributableToNonvestedSharesWithForfeitableDividends_18D3ADB610FD59307EE49C2314EFF948" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Incremental Common Shares Attributable to Dilutive Effect of Nonvested Shares with Forfeitable Dividends</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_IncrementalCommonSharesAttributableToNonvestedSharesWithForfeitableDividends" xlink:label="loc_us-gaap_IncrementalCommonSharesAttributableToNonvestedSharesWithForfeitableDividends_18D3ADB610FD59307EE49C2314EFF948" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncrementalCommonSharesAttributableToNonvestedSharesWithForfeitableDividends_18D3ADB610FD59307EE49C2314EFF948" xlink:to="lab_us-gaap_IncrementalCommonSharesAttributableToNonvestedSharesWithForfeitableDividends_18D3ADB610FD59307EE49C2314EFF948" xlink:type="arc" />
    <link:label id="lab_us-gaap_IncrementalCommonSharesAttributableToConversionOfDebtSecurities_843D8266507AC62B39299C2314F0AA9B_terseLabel_en-US" xlink:label="lab_us-gaap_IncrementalCommonSharesAttributableToConversionOfDebtSecurities_843D8266507AC62B39299C2314F0AA9B" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Convertible notes</link:label>
    <link:label id="lab_us-gaap_IncrementalCommonSharesAttributableToConversionOfDebtSecurities_843D8266507AC62B39299C2314F0AA9B_label_en-US" xlink:label="lab_us-gaap_IncrementalCommonSharesAttributableToConversionOfDebtSecurities_843D8266507AC62B39299C2314F0AA9B" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Incremental Common Shares Attributable to Dilutive Effect of Conversion of Debt Securities</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_IncrementalCommonSharesAttributableToConversionOfDebtSecurities" xlink:label="loc_us-gaap_IncrementalCommonSharesAttributableToConversionOfDebtSecurities_843D8266507AC62B39299C2314F0AA9B" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncrementalCommonSharesAttributableToConversionOfDebtSecurities_843D8266507AC62B39299C2314F0AA9B" xlink:to="lab_us-gaap_IncrementalCommonSharesAttributableToConversionOfDebtSecurities_843D8266507AC62B39299C2314F0AA9B" xlink:type="arc" />
    <link:label id="lab_us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding_D114C380166B69E4306B9C2314F0BC1D_totalLabel_en-US" xlink:label="lab_us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding_D114C380166B69E4306B9C2314F0BC1D" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Average shares outstanding - diluted</link:label>
    <link:label id="lab_us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding_D114C380166B69E4306B9C2314F0BC1D_label_en-US" xlink:label="lab_us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding_D114C380166B69E4306B9C2314F0BC1D" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Weighted Average Number of Shares Outstanding, Diluted</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding" xlink:label="loc_us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding_D114C380166B69E4306B9C2314F0BC1D" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding_D114C380166B69E4306B9C2314F0BC1D" xlink:to="lab_us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding_D114C380166B69E4306B9C2314F0BC1D" xlink:type="arc" />
    <link:label id="lab_us-gaap_SupplementalCashFlowInformationAbstract_7F84F0B8B3B4F792DEAC7C362CF5071D_label_en-US" xlink:label="lab_us-gaap_SupplementalCashFlowInformationAbstract_7F84F0B8B3B4F792DEAC7C362CF5071D" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Supplemental Cash Flow Information [Abstract]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_SupplementalCashFlowInformationAbstract" xlink:label="loc_us-gaap_SupplementalCashFlowInformationAbstract_7F84F0B8B3B4F792DEAC7C362CF5071D" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SupplementalCashFlowInformationAbstract_7F84F0B8B3B4F792DEAC7C362CF5071D" xlink:to="lab_us-gaap_SupplementalCashFlowInformationAbstract_7F84F0B8B3B4F792DEAC7C362CF5071D" xlink:type="arc" />
    <link:label id="lab_us-gaap_InterestPaidNet_6C1567071AB1A7EEBC6C7C362CF5BEA3_terseLabel_en-US" xlink:label="lab_us-gaap_InterestPaidNet_6C1567071AB1A7EEBC6C7C362CF5BEA3" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Interest, net of amount capitalized</link:label>
    <link:label id="lab_us-gaap_InterestPaidNet_6C1567071AB1A7EEBC6C7C362CF5BEA3_label_en-US" xlink:label="lab_us-gaap_InterestPaidNet_6C1567071AB1A7EEBC6C7C362CF5BEA3" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Interest Paid, Excluding Capitalized Interest, Operating Activities</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_InterestPaidNet" xlink:label="loc_us-gaap_InterestPaidNet_6C1567071AB1A7EEBC6C7C362CF5BEA3" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_InterestPaidNet_6C1567071AB1A7EEBC6C7C362CF5BEA3" xlink:to="lab_us-gaap_InterestPaidNet_6C1567071AB1A7EEBC6C7C362CF5BEA3" xlink:type="arc" />
    <link:label id="lab_us-gaap_IncomeTaxesPaidNet_327AE9742CCC8F2E97167C362CF5806F_terseLabel_en-US" xlink:label="lab_us-gaap_IncomeTaxesPaidNet_327AE9742CCC8F2E97167C362CF5806F" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Income taxes, net of amount refunded</link:label>
    <link:label id="lab_us-gaap_IncomeTaxesPaidNet_327AE9742CCC8F2E97167C362CF5806F_label_en-US" xlink:label="lab_us-gaap_IncomeTaxesPaidNet_327AE9742CCC8F2E97167C362CF5806F" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Income Taxes Paid, Net</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_IncomeTaxesPaidNet" xlink:label="loc_us-gaap_IncomeTaxesPaidNet_327AE9742CCC8F2E97167C362CF5806F" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncomeTaxesPaidNet_327AE9742CCC8F2E97167C362CF5806F" xlink:to="lab_us-gaap_IncomeTaxesPaidNet_327AE9742CCC8F2E97167C362CF5806F" xlink:type="arc" />
    <link:label id="lab_us-gaap_ScheduleOfEntityWideRevenueByMajorCustomersByReportingSegmentsTable_FB1D7FBAECD57401A659EDECD1C7578B_terseLabel_en-US" xlink:label="lab_us-gaap_ScheduleOfEntityWideRevenueByMajorCustomersByReportingSegmentsTable_FB1D7FBAECD57401A659EDECD1C7578B" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Schedule of Revenue by Major Customers, by Reporting Segments [Table]</link:label>
    <link:label id="lab_us-gaap_ScheduleOfEntityWideRevenueByMajorCustomersByReportingSegmentsTable_FB1D7FBAECD57401A659EDECD1C7578B_label_en-US" xlink:label="lab_us-gaap_ScheduleOfEntityWideRevenueByMajorCustomersByReportingSegmentsTable_FB1D7FBAECD57401A659EDECD1C7578B" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Schedule of Revenue by Major Customers, by Reporting Segments [Table]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ScheduleOfEntityWideRevenueByMajorCustomersByReportingSegmentsTable" xlink:label="loc_us-gaap_ScheduleOfEntityWideRevenueByMajorCustomersByReportingSegmentsTable_FB1D7FBAECD57401A659EDECD1C7578B" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfEntityWideRevenueByMajorCustomersByReportingSegmentsTable_FB1D7FBAECD57401A659EDECD1C7578B" xlink:to="lab_us-gaap_ScheduleOfEntityWideRevenueByMajorCustomersByReportingSegmentsTable_FB1D7FBAECD57401A659EDECD1C7578B" xlink:type="arc" />
    <link:label id="lab_us-gaap_OperatingSegmentsMember_F3464DDF11DC82578E0EEDECD1C80BE2_verboseLabel_en-US" xlink:label="lab_us-gaap_OperatingSegmentsMember_F3464DDF11DC82578E0EEDECD1C80BE2" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Total Segment</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_OperatingSegmentsMember" xlink:label="loc_us-gaap_OperatingSegmentsMember_F3464DDF11DC82578E0EEDECD1C80BE2" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OperatingSegmentsMember_F3464DDF11DC82578E0EEDECD1C80BE2" xlink:to="lab_us-gaap_OperatingSegmentsMember_F3464DDF11DC82578E0EEDECD1C80BE2" xlink:type="arc" />
    <link:label id="lab_srt_ProductOrServiceAxis_2B5CD08975E184889212EDECD1CAEABE_terseLabel_en-US" xlink:label="lab_srt_ProductOrServiceAxis_2B5CD08975E184889212EDECD1CAEABE" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Product and Service [Axis]</link:label>
    <link:label id="lab_srt_ProductOrServiceAxis_2B5CD08975E184889212EDECD1CAEABE_label_en-US" xlink:label="lab_srt_ProductOrServiceAxis_2B5CD08975E184889212EDECD1CAEABE" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Product and Service [Axis]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_ProductOrServiceAxis" xlink:label="loc_srt_ProductOrServiceAxis_2B5CD08975E184889212EDECD1CAEABE" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_srt_ProductOrServiceAxis_2B5CD08975E184889212EDECD1CAEABE" xlink:to="lab_srt_ProductOrServiceAxis_2B5CD08975E184889212EDECD1CAEABE" xlink:type="arc" />
    <link:label id="lab_srt_ProductsAndServicesDomain_9AF9F7C3D923B9858545EDECD1CA9A8B_terseLabel_en-US" xlink:label="lab_srt_ProductsAndServicesDomain_9AF9F7C3D923B9858545EDECD1CA9A8B" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Product and Service [Domain]</link:label>
    <link:label id="lab_srt_ProductsAndServicesDomain_9AF9F7C3D923B9858545EDECD1CA9A8B_label_en-US" xlink:label="lab_srt_ProductsAndServicesDomain_9AF9F7C3D923B9858545EDECD1CA9A8B" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Product and Service [Domain]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_ProductsAndServicesDomain" xlink:label="loc_srt_ProductsAndServicesDomain_9AF9F7C3D923B9858545EDECD1CA9A8B" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_srt_ProductsAndServicesDomain_9AF9F7C3D923B9858545EDECD1CA9A8B" xlink:to="lab_srt_ProductsAndServicesDomain_9AF9F7C3D923B9858545EDECD1CA9A8B" xlink:type="arc" />
    <link:label id="lab_arnc_AreospaceMember_5FC520495225DBEC65FFEDECD1CA4F15_terseLabel_en-US" xlink:label="lab_arnc_AreospaceMember_5FC520495225DBEC65FFEDECD1CA4F15" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Aerospace</link:label>
    <link:label id="lab_arnc_AreospaceMember_5FC520495225DBEC65FFEDECD1CA4F15_label_en-US" xlink:label="lab_arnc_AreospaceMember_5FC520495225DBEC65FFEDECD1CA4F15" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Areospace [Member]</link:label>
    <link:label id="lab_arnc_AreospaceMember_5FC520495225DBEC65FFEDECD1CA4F15_documentation_en-US" xlink:label="lab_arnc_AreospaceMember_5FC520495225DBEC65FFEDECD1CA4F15" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Areospace [Member]</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_AreospaceMember" xlink:label="loc_arnc_AreospaceMember_5FC520495225DBEC65FFEDECD1CA4F15" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_AreospaceMember_5FC520495225DBEC65FFEDECD1CA4F15" xlink:to="lab_arnc_AreospaceMember_5FC520495225DBEC65FFEDECD1CA4F15" xlink:type="arc" />
    <link:label id="lab_arnc_TransportationMember_6A9DA964AA5B68E07A61EDECD1CA665A_terseLabel_en-US" xlink:label="lab_arnc_TransportationMember_6A9DA964AA5B68E07A61EDECD1CA665A" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Transportation</link:label>
    <link:label id="lab_arnc_TransportationMember_6A9DA964AA5B68E07A61EDECD1CA665A_label_en-US" xlink:label="lab_arnc_TransportationMember_6A9DA964AA5B68E07A61EDECD1CA665A" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Transportation [Member]</link:label>
    <link:label id="lab_arnc_TransportationMember_6A9DA964AA5B68E07A61EDECD1CA665A_documentation_en-US" xlink:label="lab_arnc_TransportationMember_6A9DA964AA5B68E07A61EDECD1CA665A" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Transportation [Member]</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_TransportationMember" xlink:label="loc_arnc_TransportationMember_6A9DA964AA5B68E07A61EDECD1CA665A" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_TransportationMember_6A9DA964AA5B68E07A61EDECD1CA665A" xlink:to="lab_arnc_TransportationMember_6A9DA964AA5B68E07A61EDECD1CA665A" xlink:type="arc" />
    <link:label id="lab_arnc_BuildingAndConstructionMember_B5A2902DDE0B7C9DF08FEDECD1CB8C2B_terseLabel_en-US" xlink:label="lab_arnc_BuildingAndConstructionMember_B5A2902DDE0B7C9DF08FEDECD1CB8C2B" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Building and construction</link:label>
    <link:label id="lab_arnc_BuildingAndConstructionMember_B5A2902DDE0B7C9DF08FEDECD1CB8C2B_label_en-US" xlink:label="lab_arnc_BuildingAndConstructionMember_B5A2902DDE0B7C9DF08FEDECD1CB8C2B" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Building And Construction [Member]</link:label>
    <link:label id="lab_arnc_BuildingAndConstructionMember_B5A2902DDE0B7C9DF08FEDECD1CB8C2B_documentation_en-US" xlink:label="lab_arnc_BuildingAndConstructionMember_B5A2902DDE0B7C9DF08FEDECD1CB8C2B" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Building And Construction [Member]</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_BuildingAndConstructionMember" xlink:label="loc_arnc_BuildingAndConstructionMember_B5A2902DDE0B7C9DF08FEDECD1CB8C2B" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_BuildingAndConstructionMember_B5A2902DDE0B7C9DF08FEDECD1CB8C2B" xlink:to="lab_arnc_BuildingAndConstructionMember_B5A2902DDE0B7C9DF08FEDECD1CB8C2B" xlink:type="arc" />
    <link:label id="lab_arnc_IndustrialAndOtherMember_B02DDAC47096BA962BB8EDECD1CB44A3_terseLabel_en-US" xlink:label="lab_arnc_IndustrialAndOtherMember_B02DDAC47096BA962BB8EDECD1CB44A3" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Industrial and Other</link:label>
    <link:label id="lab_arnc_IndustrialAndOtherMember_B02DDAC47096BA962BB8EDECD1CB44A3_label_en-US" xlink:label="lab_arnc_IndustrialAndOtherMember_B02DDAC47096BA962BB8EDECD1CB44A3" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Industrial And Other [Member]</link:label>
    <link:label id="lab_arnc_IndustrialAndOtherMember_B02DDAC47096BA962BB8EDECD1CB44A3_documentation_en-US" xlink:label="lab_arnc_IndustrialAndOtherMember_B02DDAC47096BA962BB8EDECD1CB44A3" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Industrial And Other [Member]</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_IndustrialAndOtherMember" xlink:label="loc_arnc_IndustrialAndOtherMember_B02DDAC47096BA962BB8EDECD1CB44A3" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_IndustrialAndOtherMember_B02DDAC47096BA962BB8EDECD1CB44A3" xlink:to="lab_arnc_IndustrialAndOtherMember_B02DDAC47096BA962BB8EDECD1CB44A3" xlink:type="arc" />
    <link:label id="lab_us-gaap_EntityWideRevenueMajorCustomerLineItems_F03B307923EA3467B679EDECD1CBE8FA_terseLabel_en-US" xlink:label="lab_us-gaap_EntityWideRevenueMajorCustomerLineItems_F03B307923EA3467B679EDECD1CBE8FA" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Revenue, Major Customer [Line Items]</link:label>
    <link:label id="lab_us-gaap_EntityWideRevenueMajorCustomerLineItems_F03B307923EA3467B679EDECD1CBE8FA_label_en-US" xlink:label="lab_us-gaap_EntityWideRevenueMajorCustomerLineItems_F03B307923EA3467B679EDECD1CBE8FA" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Revenue, Major Customer [Line Items]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_EntityWideRevenueMajorCustomerLineItems" xlink:label="loc_us-gaap_EntityWideRevenueMajorCustomerLineItems_F03B307923EA3467B679EDECD1CBE8FA" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_EntityWideRevenueMajorCustomerLineItems_F03B307923EA3467B679EDECD1CBE8FA" xlink:to="lab_us-gaap_EntityWideRevenueMajorCustomerLineItems_F03B307923EA3467B679EDECD1CBE8FA" xlink:type="arc" />
    <link:label id="lab_arnc_ContractWithCustomerClaimsForNewProductIntroductions_B3CB970BAACB50F336EBEDECD1CB97E1_terseLabel_en-US" xlink:label="lab_arnc_ContractWithCustomerClaimsForNewProductIntroductions_B3CB970BAACB50F336EBEDECD1CB97E1" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Costs related to settlements of certain customer claims</link:label>
    <link:label id="lab_arnc_ContractWithCustomerClaimsForNewProductIntroductions_B3CB970BAACB50F336EBEDECD1CB97E1_label_en-US" xlink:label="lab_arnc_ContractWithCustomerClaimsForNewProductIntroductions_B3CB970BAACB50F336EBEDECD1CB97E1" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Contract With Customer, Claims For New Product Introductions</link:label>
    <link:label id="lab_arnc_ContractWithCustomerClaimsForNewProductIntroductions_B3CB970BAACB50F336EBEDECD1CB97E1_documentation_en-US" xlink:label="lab_arnc_ContractWithCustomerClaimsForNewProductIntroductions_B3CB970BAACB50F336EBEDECD1CB97E1" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Contract With Customer, Claims For New Product Introductions</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_ContractWithCustomerClaimsForNewProductIntroductions" xlink:label="loc_arnc_ContractWithCustomerClaimsForNewProductIntroductions_B3CB970BAACB50F336EBEDECD1CB97E1" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_ContractWithCustomerClaimsForNewProductIntroductions_B3CB970BAACB50F336EBEDECD1CB97E1" xlink:to="lab_arnc_ContractWithCustomerClaimsForNewProductIntroductions_B3CB970BAACB50F336EBEDECD1CB97E1" xlink:type="arc" />
    <link:label id="lab_arnc_ShortTermDebtExcludingCurrentMaturitiesOfLongtermDebt_47C598BA3072683E03311087256A2CA5_terseLabel_en-US" xlink:label="lab_arnc_ShortTermDebtExcludingCurrentMaturitiesOfLongtermDebt_47C598BA3072683E03311087256A2CA5" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Short-term debt</link:label>
    <link:label id="lab_arnc_ShortTermDebtExcludingCurrentMaturitiesOfLongtermDebt_47C598BA3072683E03311087256A2CA5_label_en-US" xlink:label="lab_arnc_ShortTermDebtExcludingCurrentMaturitiesOfLongtermDebt_47C598BA3072683E03311087256A2CA5" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Short-Term Debt, Excluding Current Maturities Of Long-term Debt</link:label>
    <link:label id="lab_arnc_ShortTermDebtExcludingCurrentMaturitiesOfLongtermDebt_47C598BA3072683E03311087256A2CA5_documentation_en-US" xlink:label="lab_arnc_ShortTermDebtExcludingCurrentMaturitiesOfLongtermDebt_47C598BA3072683E03311087256A2CA5" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Short-Term Debt, Excluding Current Maturities Of Long-Term Debt</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_ShortTermDebtExcludingCurrentMaturitiesOfLongtermDebt" xlink:label="loc_arnc_ShortTermDebtExcludingCurrentMaturitiesOfLongtermDebt_47C598BA3072683E03311087256A2CA5" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_ShortTermDebtExcludingCurrentMaturitiesOfLongtermDebt_47C598BA3072683E03311087256A2CA5" xlink:to="lab_arnc_ShortTermDebtExcludingCurrentMaturitiesOfLongtermDebt_47C598BA3072683E03311087256A2CA5" xlink:type="arc" />
    <link:label id="lab_arnc_AccountsPayableSettlementArrangements_CE538EA404FF8ABF09BB1087256A550A_terseLabel_en-US" xlink:label="lab_arnc_AccountsPayableSettlementArrangements_CE538EA404FF8ABF09BB1087256A550A" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Accounts payable settlement arrangements</link:label>
    <link:label id="lab_arnc_AccountsPayableSettlementArrangements_CE538EA404FF8ABF09BB1087256A550A_label_en-US" xlink:label="lab_arnc_AccountsPayableSettlementArrangements_CE538EA404FF8ABF09BB1087256A550A" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Accounts Payable Settlement Arrangements</link:label>
    <link:label id="lab_arnc_AccountsPayableSettlementArrangements_CE538EA404FF8ABF09BB1087256A550A_documentation_en-US" xlink:label="lab_arnc_AccountsPayableSettlementArrangements_CE538EA404FF8ABF09BB1087256A550A" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Accounts payable settlement arrangements.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_AccountsPayableSettlementArrangements" xlink:label="loc_arnc_AccountsPayableSettlementArrangements_CE538EA404FF8ABF09BB1087256A550A" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_AccountsPayableSettlementArrangements_CE538EA404FF8ABF09BB1087256A550A" xlink:to="lab_arnc_AccountsPayableSettlementArrangements_CE538EA404FF8ABF09BB1087256A550A" xlink:type="arc" />
    <link:label id="lab_us-gaap_AllowanceForDoubtfulAccountsReceivableCurrent_123A87260DAFFABB16AE7C3630AC3645_terseLabel_en-US" xlink:label="lab_us-gaap_AllowanceForDoubtfulAccountsReceivableCurrent_123A87260DAFFABB16AE7C3630AC3645" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Receivables from customers, allowance</link:label>
    <link:label id="lab_us-gaap_AllowanceForDoubtfulAccountsReceivableCurrent_123A87260DAFFABB16AE7C3630AC3645_label_en-US" xlink:label="lab_us-gaap_AllowanceForDoubtfulAccountsReceivableCurrent_123A87260DAFFABB16AE7C3630AC3645" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Allowance for Doubtful Accounts Receivable, Current</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AllowanceForDoubtfulAccountsReceivableCurrent" xlink:label="loc_us-gaap_AllowanceForDoubtfulAccountsReceivableCurrent_123A87260DAFFABB16AE7C3630AC3645" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AllowanceForDoubtfulAccountsReceivableCurrent_123A87260DAFFABB16AE7C3630AC3645" xlink:to="lab_us-gaap_AllowanceForDoubtfulAccountsReceivableCurrent_123A87260DAFFABB16AE7C3630AC3645" xlink:type="arc" />
    <link:label id="lab_us-gaap_CommitmentsAndContingenciesDisclosureAbstract_F5490F62BA3E2C88AAF406E20AB46A21_label_en-US" xlink:label="lab_us-gaap_CommitmentsAndContingenciesDisclosureAbstract_F5490F62BA3E2C88AAF406E20AB46A21" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Commitments and Contingencies Disclosure [Abstract]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_CommitmentsAndContingenciesDisclosureAbstract" xlink:label="loc_us-gaap_CommitmentsAndContingenciesDisclosureAbstract_F5490F62BA3E2C88AAF406E20AB46A21" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CommitmentsAndContingenciesDisclosureAbstract_F5490F62BA3E2C88AAF406E20AB46A21" xlink:to="lab_us-gaap_CommitmentsAndContingenciesDisclosureAbstract_F5490F62BA3E2C88AAF406E20AB46A21" xlink:type="arc" />
    <link:label id="lab_us-gaap_LossContingenciesTable_4A41BB5F82D663DCDFCE06E20AB49807_terseLabel_en-US" xlink:label="lab_us-gaap_LossContingenciesTable_4A41BB5F82D663DCDFCE06E20AB49807" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Loss Contingencies [Table]</link:label>
    <link:label id="lab_us-gaap_LossContingenciesTable_4A41BB5F82D663DCDFCE06E20AB49807_label_en-US" xlink:label="lab_us-gaap_LossContingenciesTable_4A41BB5F82D663DCDFCE06E20AB49807" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Loss Contingencies [Table]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_LossContingenciesTable" xlink:label="loc_us-gaap_LossContingenciesTable_4A41BB5F82D663DCDFCE06E20AB49807" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LossContingenciesTable_4A41BB5F82D663DCDFCE06E20AB49807" xlink:to="lab_us-gaap_LossContingenciesTable_4A41BB5F82D663DCDFCE06E20AB49807" xlink:type="arc" />
    <link:label id="lab_us-gaap_TypeOfArrangementAxis_CFAFFE9BE9965513CBDC06E20AB46A04_terseLabel_en-US" xlink:label="lab_us-gaap_TypeOfArrangementAxis_CFAFFE9BE9965513CBDC06E20AB46A04" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Type of Arrangement and Non-arrangement Transactions [Axis]</link:label>
    <link:label id="lab_us-gaap_TypeOfArrangementAxis_CFAFFE9BE9965513CBDC06E20AB46A04_label_en-US" xlink:label="lab_us-gaap_TypeOfArrangementAxis_CFAFFE9BE9965513CBDC06E20AB46A04" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Type of Arrangement and Non-arrangement Transactions [Axis]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_TypeOfArrangementAxis" xlink:label="loc_us-gaap_TypeOfArrangementAxis_CFAFFE9BE9965513CBDC06E20AB46A04" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_TypeOfArrangementAxis_CFAFFE9BE9965513CBDC06E20AB46A04" xlink:to="lab_us-gaap_TypeOfArrangementAxis_CFAFFE9BE9965513CBDC06E20AB46A04" xlink:type="arc" />
    <link:label id="lab_us-gaap_ArrangementsAndNonarrangementTransactionsMember_3236EDAC5A60794D5B3B06E20AB48597_terseLabel_en-US" xlink:label="lab_us-gaap_ArrangementsAndNonarrangementTransactionsMember_3236EDAC5A60794D5B3B06E20AB48597" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Arrangements and Non-arrangement Transactions [Domain]</link:label>
    <link:label id="lab_us-gaap_ArrangementsAndNonarrangementTransactionsMember_3236EDAC5A60794D5B3B06E20AB48597_label_en-US" xlink:label="lab_us-gaap_ArrangementsAndNonarrangementTransactionsMember_3236EDAC5A60794D5B3B06E20AB48597" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Arrangements and Non-arrangement Transactions [Domain]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ArrangementsAndNonarrangementTransactionsMember" xlink:label="loc_us-gaap_ArrangementsAndNonarrangementTransactionsMember_3236EDAC5A60794D5B3B06E20AB48597" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ArrangementsAndNonarrangementTransactionsMember_3236EDAC5A60794D5B3B06E20AB48597" xlink:to="lab_us-gaap_ArrangementsAndNonarrangementTransactionsMember_3236EDAC5A60794D5B3B06E20AB48597" xlink:type="arc" />
    <link:label id="lab_arnc_SeparationAgreementMember_9E77EF5235D74BCA942006E20AB55AD2_terseLabel_en-US" xlink:label="lab_arnc_SeparationAgreementMember_9E77EF5235D74BCA942006E20AB55AD2" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Separation Agreement</link:label>
    <link:label id="lab_arnc_SeparationAgreementMember_9E77EF5235D74BCA942006E20AB55AD2_label_en-US" xlink:label="lab_arnc_SeparationAgreementMember_9E77EF5235D74BCA942006E20AB55AD2" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Separation Agreement [Member]</link:label>
    <link:label id="lab_arnc_SeparationAgreementMember_9E77EF5235D74BCA942006E20AB55AD2_documentation_en-US" xlink:label="lab_arnc_SeparationAgreementMember_9E77EF5235D74BCA942006E20AB55AD2" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Separation agreement.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_SeparationAgreementMember" xlink:label="loc_arnc_SeparationAgreementMember_9E77EF5235D74BCA942006E20AB55AD2" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_SeparationAgreementMember_9E77EF5235D74BCA942006E20AB55AD2" xlink:to="lab_arnc_SeparationAgreementMember_9E77EF5235D74BCA942006E20AB55AD2" xlink:type="arc" />
    <link:label id="lab_us-gaap_InvestmentTypeAxis_44A3B2706AC14D4AC64A06E20AB569BC_terseLabel_en-US" xlink:label="lab_us-gaap_InvestmentTypeAxis_44A3B2706AC14D4AC64A06E20AB569BC" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Investment Type [Axis]</link:label>
    <link:label id="lab_us-gaap_InvestmentTypeAxis_44A3B2706AC14D4AC64A06E20AB569BC_label_en-US" xlink:label="lab_us-gaap_InvestmentTypeAxis_44A3B2706AC14D4AC64A06E20AB569BC" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Investment Type [Axis]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_InvestmentTypeAxis" xlink:label="loc_us-gaap_InvestmentTypeAxis_44A3B2706AC14D4AC64A06E20AB569BC" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_InvestmentTypeAxis_44A3B2706AC14D4AC64A06E20AB569BC" xlink:to="lab_us-gaap_InvestmentTypeAxis_44A3B2706AC14D4AC64A06E20AB569BC" xlink:type="arc" />
    <link:label id="lab_us-gaap_InvestmentTypeCategorizationMember_4E9CB7CEEB645A4A3E0006E20ABAB336_terseLabel_en-US" xlink:label="lab_us-gaap_InvestmentTypeCategorizationMember_4E9CB7CEEB645A4A3E0006E20ABAB336" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Investments [Domain]</link:label>
    <link:label id="lab_us-gaap_InvestmentTypeCategorizationMember_4E9CB7CEEB645A4A3E0006E20ABAB336_label_en-US" xlink:label="lab_us-gaap_InvestmentTypeCategorizationMember_4E9CB7CEEB645A4A3E0006E20ABAB336" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Investments [Domain]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_InvestmentTypeCategorizationMember" xlink:label="loc_us-gaap_InvestmentTypeCategorizationMember_4E9CB7CEEB645A4A3E0006E20ABAB336" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_InvestmentTypeCategorizationMember_4E9CB7CEEB645A4A3E0006E20ABAB336" xlink:to="lab_us-gaap_InvestmentTypeCategorizationMember_4E9CB7CEEB645A4A3E0006E20ABAB336" xlink:type="arc" />
    <link:label id="lab_us-gaap_BankLoanObligationsMember_6C9C7A27A3EBAFCAF0FF06E20ABAF759_terseLabel_en-US" xlink:label="lab_us-gaap_BankLoanObligationsMember_6C9C7A27A3EBAFCAF0FF06E20ABAF759" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Bank Loan Obligations</link:label>
    <link:label id="lab_us-gaap_BankLoanObligationsMember_6C9C7A27A3EBAFCAF0FF06E20ABAF759_label_en-US" xlink:label="lab_us-gaap_BankLoanObligationsMember_6C9C7A27A3EBAFCAF0FF06E20ABAF759" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Bank Loan Obligations [Member]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_BankLoanObligationsMember" xlink:label="loc_us-gaap_BankLoanObligationsMember_6C9C7A27A3EBAFCAF0FF06E20ABAF759" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_BankLoanObligationsMember_6C9C7A27A3EBAFCAF0FF06E20ABAF759" xlink:to="lab_us-gaap_BankLoanObligationsMember_6C9C7A27A3EBAFCAF0FF06E20ABAF759" xlink:type="arc" />
    <link:label id="lab_us-gaap_DebtInstrumentAxis_9E6FDAC6D3C1B85FE19206E20ABB530B_terseLabel_en-US" xlink:label="lab_us-gaap_DebtInstrumentAxis_9E6FDAC6D3C1B85FE19206E20ABB530B" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Debt Instrument [Axis]</link:label>
    <link:label id="lab_us-gaap_DebtInstrumentAxis_9E6FDAC6D3C1B85FE19206E20ABB530B_label_en-US" xlink:label="lab_us-gaap_DebtInstrumentAxis_9E6FDAC6D3C1B85FE19206E20ABB530B" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Debt Instrument [Axis]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DebtInstrumentAxis" xlink:label="loc_us-gaap_DebtInstrumentAxis_9E6FDAC6D3C1B85FE19206E20ABB530B" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DebtInstrumentAxis_9E6FDAC6D3C1B85FE19206E20ABB530B" xlink:to="lab_us-gaap_DebtInstrumentAxis_9E6FDAC6D3C1B85FE19206E20ABB530B" xlink:type="arc" />
    <link:label id="lab_us-gaap_DebtInstrumentNameDomain_81A9DF5BB89C873A191F06E20ABB94C4_terseLabel_en-US" xlink:label="lab_us-gaap_DebtInstrumentNameDomain_81A9DF5BB89C873A191F06E20ABB94C4" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Debt Instrument, Name [Domain]</link:label>
    <link:label id="lab_us-gaap_DebtInstrumentNameDomain_81A9DF5BB89C873A191F06E20ABB94C4_label_en-US" xlink:label="lab_us-gaap_DebtInstrumentNameDomain_81A9DF5BB89C873A191F06E20ABB94C4" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Debt Instrument, Name [Domain]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DebtInstrumentNameDomain" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_81A9DF5BB89C873A191F06E20ABB94C4" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_81A9DF5BB89C873A191F06E20ABB94C4" xlink:to="lab_us-gaap_DebtInstrumentNameDomain_81A9DF5BB89C873A191F06E20ABB94C4" xlink:type="arc" />
    <link:label id="lab_us-gaap_LossContingenciesByNatureOfContingencyAxis_09629A68F0A56E7B49E106E20ABC24BA_terseLabel_en-US" xlink:label="lab_us-gaap_LossContingenciesByNatureOfContingencyAxis_09629A68F0A56E7B49E106E20ABC24BA" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Loss Contingency Nature [Axis]</link:label>
    <link:label id="lab_us-gaap_LossContingenciesByNatureOfContingencyAxis_09629A68F0A56E7B49E106E20ABC24BA_label_en-US" xlink:label="lab_us-gaap_LossContingenciesByNatureOfContingencyAxis_09629A68F0A56E7B49E106E20ABC24BA" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Loss Contingency Nature [Axis]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_LossContingenciesByNatureOfContingencyAxis" xlink:label="loc_us-gaap_LossContingenciesByNatureOfContingencyAxis_09629A68F0A56E7B49E106E20ABC24BA" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LossContingenciesByNatureOfContingencyAxis_09629A68F0A56E7B49E106E20ABC24BA" xlink:to="lab_us-gaap_LossContingenciesByNatureOfContingencyAxis_09629A68F0A56E7B49E106E20ABC24BA" xlink:type="arc" />
    <link:label id="lab_us-gaap_LossContingencyNatureDomain_A99DF845C0C2541B761606E20ABCD7C4_terseLabel_en-US" xlink:label="lab_us-gaap_LossContingencyNatureDomain_A99DF845C0C2541B761606E20ABCD7C4" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Loss Contingency, Nature [Domain]</link:label>
    <link:label id="lab_us-gaap_LossContingencyNatureDomain_A99DF845C0C2541B761606E20ABCD7C4_label_en-US" xlink:label="lab_us-gaap_LossContingencyNatureDomain_A99DF845C0C2541B761606E20ABCD7C4" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Loss Contingency, Nature [Domain]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_LossContingencyNatureDomain" xlink:label="loc_us-gaap_LossContingencyNatureDomain_A99DF845C0C2541B761606E20ABCD7C4" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LossContingencyNatureDomain_A99DF845C0C2541B761606E20ABCD7C4" xlink:to="lab_us-gaap_LossContingencyNatureDomain_A99DF845C0C2541B761606E20ABCD7C4" xlink:type="arc" />
    <link:label id="lab_arnc_PurchaseAgreementMember_F631CC11206950F70C6206E20ABC2379_terseLabel_en-US" xlink:label="lab_arnc_PurchaseAgreementMember_F631CC11206950F70C6206E20ABC2379" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Purchase Agreement</link:label>
    <link:label id="lab_arnc_PurchaseAgreementMember_F631CC11206950F70C6206E20ABC2379_label_en-US" xlink:label="lab_arnc_PurchaseAgreementMember_F631CC11206950F70C6206E20ABC2379" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Purchase Agreement [Member]</link:label>
    <link:label id="lab_arnc_PurchaseAgreementMember_F631CC11206950F70C6206E20ABC2379_documentation_en-US" xlink:label="lab_arnc_PurchaseAgreementMember_F631CC11206950F70C6206E20ABC2379" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Purchase agreement.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_PurchaseAgreementMember" xlink:label="loc_arnc_PurchaseAgreementMember_F631CC11206950F70C6206E20ABC2379" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_PurchaseAgreementMember_F631CC11206950F70C6206E20ABC2379" xlink:to="lab_arnc_PurchaseAgreementMember_F631CC11206950F70C6206E20ABC2379" xlink:type="arc" />
    <link:label id="lab_arnc_AlcoaCorporationWorkersCompensationClaimsMember_875D5BFA7CD6D30472B406E20ABC611A_terseLabel_en-US" xlink:label="lab_arnc_AlcoaCorporationWorkersCompensationClaimsMember_875D5BFA7CD6D30472B406E20ABC611A" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Alcoa Corporation Workers Compensation Claims</link:label>
    <link:label id="lab_arnc_AlcoaCorporationWorkersCompensationClaimsMember_875D5BFA7CD6D30472B406E20ABC611A_label_en-US" xlink:label="lab_arnc_AlcoaCorporationWorkersCompensationClaimsMember_875D5BFA7CD6D30472B406E20ABC611A" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Alcoa Corporation Workers Compensation Claims [Member]</link:label>
    <link:label id="lab_arnc_AlcoaCorporationWorkersCompensationClaimsMember_875D5BFA7CD6D30472B406E20ABC611A_documentation_en-US" xlink:label="lab_arnc_AlcoaCorporationWorkersCompensationClaimsMember_875D5BFA7CD6D30472B406E20ABC611A" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Alcoa corporation workers compensation claims.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_AlcoaCorporationWorkersCompensationClaimsMember" xlink:label="loc_arnc_AlcoaCorporationWorkersCompensationClaimsMember_875D5BFA7CD6D30472B406E20ABC611A" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_AlcoaCorporationWorkersCompensationClaimsMember_875D5BFA7CD6D30472B406E20ABC611A" xlink:to="lab_arnc_AlcoaCorporationWorkersCompensationClaimsMember_875D5BFA7CD6D30472B406E20ABC611A" xlink:type="arc" />
    <link:label id="lab_us-gaap_BalanceSheetLocationAxis_0D8C6658741362AF551B06E20ABC2D66_terseLabel_en-US" xlink:label="lab_us-gaap_BalanceSheetLocationAxis_0D8C6658741362AF551B06E20ABC2D66" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Balance Sheet Location [Axis]</link:label>
    <link:label id="lab_us-gaap_BalanceSheetLocationAxis_0D8C6658741362AF551B06E20ABC2D66_label_en-US" xlink:label="lab_us-gaap_BalanceSheetLocationAxis_0D8C6658741362AF551B06E20ABC2D66" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Balance Sheet Location [Axis]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_BalanceSheetLocationAxis" xlink:label="loc_us-gaap_BalanceSheetLocationAxis_0D8C6658741362AF551B06E20ABC2D66" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_BalanceSheetLocationAxis_0D8C6658741362AF551B06E20ABC2D66" xlink:to="lab_us-gaap_BalanceSheetLocationAxis_0D8C6658741362AF551B06E20ABC2D66" xlink:type="arc" />
    <link:label id="lab_us-gaap_BalanceSheetLocationDomain_5286150106BB825FC33906E20ABDC149_terseLabel_en-US" xlink:label="lab_us-gaap_BalanceSheetLocationDomain_5286150106BB825FC33906E20ABDC149" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Balance Sheet Location [Domain]</link:label>
    <link:label id="lab_us-gaap_BalanceSheetLocationDomain_5286150106BB825FC33906E20ABDC149_label_en-US" xlink:label="lab_us-gaap_BalanceSheetLocationDomain_5286150106BB825FC33906E20ABDC149" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Balance Sheet Location [Domain]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_BalanceSheetLocationDomain" xlink:label="loc_us-gaap_BalanceSheetLocationDomain_5286150106BB825FC33906E20ABDC149" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_BalanceSheetLocationDomain_5286150106BB825FC33906E20ABDC149" xlink:to="lab_us-gaap_BalanceSheetLocationDomain_5286150106BB825FC33906E20ABDC149" xlink:type="arc" />
    <link:label id="lab_arnc_OtherNoncurrentLiabilitiesAndDeferredCreditsMember_083F90BAF472ACD9810206E20ABD3076_terseLabel_en-US" xlink:label="lab_arnc_OtherNoncurrentLiabilitiesAndDeferredCreditsMember_083F90BAF472ACD9810206E20ABD3076" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Other Noncurrent Liabilities and Deferred Credits</link:label>
    <link:label id="lab_arnc_OtherNoncurrentLiabilitiesAndDeferredCreditsMember_083F90BAF472ACD9810206E20ABD3076_label_en-US" xlink:label="lab_arnc_OtherNoncurrentLiabilitiesAndDeferredCreditsMember_083F90BAF472ACD9810206E20ABD3076" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Other Noncurrent Liabilities And Deferred Credits [Member]</link:label>
    <link:label id="lab_arnc_OtherNoncurrentLiabilitiesAndDeferredCreditsMember_083F90BAF472ACD9810206E20ABD3076_documentation_en-US" xlink:label="lab_arnc_OtherNoncurrentLiabilitiesAndDeferredCreditsMember_083F90BAF472ACD9810206E20ABD3076" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Other noncurrent liabilities and deferred credits.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_OtherNoncurrentLiabilitiesAndDeferredCreditsMember" xlink:label="loc_arnc_OtherNoncurrentLiabilitiesAndDeferredCreditsMember_083F90BAF472ACD9810206E20ABD3076" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_OtherNoncurrentLiabilitiesAndDeferredCreditsMember_083F90BAF472ACD9810206E20ABD3076" xlink:to="lab_arnc_OtherNoncurrentLiabilitiesAndDeferredCreditsMember_083F90BAF472ACD9810206E20ABD3076" xlink:type="arc" />
    <link:label id="lab_us-gaap_LossContingenciesLineItems_E202D263EBD916CE750C06E20ABD5D91_terseLabel_en-US" xlink:label="lab_us-gaap_LossContingenciesLineItems_E202D263EBD916CE750C06E20ABD5D91" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Loss Contingencies [Line Items]</link:label>
    <link:label id="lab_us-gaap_LossContingenciesLineItems_E202D263EBD916CE750C06E20ABD5D91_label_en-US" xlink:label="lab_us-gaap_LossContingenciesLineItems_E202D263EBD916CE750C06E20ABD5D91" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Loss Contingencies [Line Items]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_LossContingenciesLineItems" xlink:label="loc_us-gaap_LossContingenciesLineItems_E202D263EBD916CE750C06E20ABD5D91" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LossContingenciesLineItems_E202D263EBD916CE750C06E20ABD5D91" xlink:to="lab_us-gaap_LossContingenciesLineItems_E202D263EBD916CE750C06E20ABD5D91" xlink:type="arc" />
    <link:label id="lab_us-gaap_RecordedUnconditionalPurchaseObligationDueWithinOneYear_556B9F3932F4C217E9C306E20ABDA703_terseLabel_en-US" xlink:label="lab_us-gaap_RecordedUnconditionalPurchaseObligationDueWithinOneYear_556B9F3932F4C217E9C306E20ABDA703" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Purchase obligations due in 2019</link:label>
    <link:label id="lab_us-gaap_RecordedUnconditionalPurchaseObligationDueWithinOneYear_556B9F3932F4C217E9C306E20ABDA703_label_en-US" xlink:label="lab_us-gaap_RecordedUnconditionalPurchaseObligationDueWithinOneYear_556B9F3932F4C217E9C306E20ABDA703" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Recorded Unconditional Purchase Obligation Due in Next Twelve Months</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RecordedUnconditionalPurchaseObligationDueWithinOneYear" xlink:label="loc_us-gaap_RecordedUnconditionalPurchaseObligationDueWithinOneYear_556B9F3932F4C217E9C306E20ABDA703" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RecordedUnconditionalPurchaseObligationDueWithinOneYear_556B9F3932F4C217E9C306E20ABDA703" xlink:to="lab_us-gaap_RecordedUnconditionalPurchaseObligationDueWithinOneYear_556B9F3932F4C217E9C306E20ABDA703" xlink:type="arc" />
    <link:label id="lab_us-gaap_RecordedUnconditionalPurchaseObligationDueInSecondYear_5D8D33E419D11B3C750506E20ABED9D2_terseLabel_en-US" xlink:label="lab_us-gaap_RecordedUnconditionalPurchaseObligationDueInSecondYear_5D8D33E419D11B3C750506E20ABED9D2" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Purchase obligations due in 2020</link:label>
    <link:label id="lab_us-gaap_RecordedUnconditionalPurchaseObligationDueInSecondYear_5D8D33E419D11B3C750506E20ABED9D2_label_en-US" xlink:label="lab_us-gaap_RecordedUnconditionalPurchaseObligationDueInSecondYear_5D8D33E419D11B3C750506E20ABED9D2" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Recorded Unconditional Purchase Obligation Due in Second Year</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RecordedUnconditionalPurchaseObligationDueInSecondYear" xlink:label="loc_us-gaap_RecordedUnconditionalPurchaseObligationDueInSecondYear_5D8D33E419D11B3C750506E20ABED9D2" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RecordedUnconditionalPurchaseObligationDueInSecondYear_5D8D33E419D11B3C750506E20ABED9D2" xlink:to="lab_us-gaap_RecordedUnconditionalPurchaseObligationDueInSecondYear_5D8D33E419D11B3C750506E20ABED9D2" xlink:type="arc" />
    <link:label id="lab_us-gaap_RecordedUnconditionalPurchaseObligationDueInThirdYear_B1B631761B9CAE71CBBF06E20ABE57A8_terseLabel_en-US" xlink:label="lab_us-gaap_RecordedUnconditionalPurchaseObligationDueInThirdYear_B1B631761B9CAE71CBBF06E20ABE57A8" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Purchase obligations due in 2021</link:label>
    <link:label id="lab_us-gaap_RecordedUnconditionalPurchaseObligationDueInThirdYear_B1B631761B9CAE71CBBF06E20ABE57A8_label_en-US" xlink:label="lab_us-gaap_RecordedUnconditionalPurchaseObligationDueInThirdYear_B1B631761B9CAE71CBBF06E20ABE57A8" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Recorded Unconditional Purchase Obligation Due in Third Year</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RecordedUnconditionalPurchaseObligationDueInThirdYear" xlink:label="loc_us-gaap_RecordedUnconditionalPurchaseObligationDueInThirdYear_B1B631761B9CAE71CBBF06E20ABE57A8" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RecordedUnconditionalPurchaseObligationDueInThirdYear_B1B631761B9CAE71CBBF06E20ABE57A8" xlink:to="lab_us-gaap_RecordedUnconditionalPurchaseObligationDueInThirdYear_B1B631761B9CAE71CBBF06E20ABE57A8" xlink:type="arc" />
    <link:label id="lab_us-gaap_RecordedUnconditionalPurchaseObligationDueInFourthYear_7629AB396923EF7761F706E20ABE343F_terseLabel_en-US" xlink:label="lab_us-gaap_RecordedUnconditionalPurchaseObligationDueInFourthYear_7629AB396923EF7761F706E20ABE343F" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Purchase obligations due in 2022</link:label>
    <link:label id="lab_us-gaap_RecordedUnconditionalPurchaseObligationDueInFourthYear_7629AB396923EF7761F706E20ABE343F_label_en-US" xlink:label="lab_us-gaap_RecordedUnconditionalPurchaseObligationDueInFourthYear_7629AB396923EF7761F706E20ABE343F" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Recorded Unconditional Purchase Obligation Due in Fourth Year</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RecordedUnconditionalPurchaseObligationDueInFourthYear" xlink:label="loc_us-gaap_RecordedUnconditionalPurchaseObligationDueInFourthYear_7629AB396923EF7761F706E20ABE343F" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RecordedUnconditionalPurchaseObligationDueInFourthYear_7629AB396923EF7761F706E20ABE343F" xlink:to="lab_us-gaap_RecordedUnconditionalPurchaseObligationDueInFourthYear_7629AB396923EF7761F706E20ABE343F" xlink:type="arc" />
    <link:label id="lab_us-gaap_RecordedUnconditionalPurchaseObligationDueInFifthYear_6B919B2DBD539661206906E20ABE75B9_terseLabel_en-US" xlink:label="lab_us-gaap_RecordedUnconditionalPurchaseObligationDueInFifthYear_6B919B2DBD539661206906E20ABE75B9" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Purchase obligations due in 2023</link:label>
    <link:label id="lab_us-gaap_RecordedUnconditionalPurchaseObligationDueInFifthYear_6B919B2DBD539661206906E20ABE75B9_label_en-US" xlink:label="lab_us-gaap_RecordedUnconditionalPurchaseObligationDueInFifthYear_6B919B2DBD539661206906E20ABE75B9" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Recorded Unconditional Purchase Obligation Due in Fifth Year</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RecordedUnconditionalPurchaseObligationDueInFifthYear" xlink:label="loc_us-gaap_RecordedUnconditionalPurchaseObligationDueInFifthYear_6B919B2DBD539661206906E20ABE75B9" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RecordedUnconditionalPurchaseObligationDueInFifthYear_6B919B2DBD539661206906E20ABE75B9" xlink:to="lab_us-gaap_RecordedUnconditionalPurchaseObligationDueInFifthYear_6B919B2DBD539661206906E20ABE75B9" xlink:type="arc" />
    <link:label id="lab_us-gaap_RecordedUnconditionalPurchaseObligationDueAfterFifthYear_18F611EA4C63C75B009306E20ABEFDE7_terseLabel_en-US" xlink:label="lab_us-gaap_RecordedUnconditionalPurchaseObligationDueAfterFifthYear_18F611EA4C63C75B009306E20ABEFDE7" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Purchase obligations due thereafter</link:label>
    <link:label id="lab_us-gaap_RecordedUnconditionalPurchaseObligationDueAfterFifthYear_18F611EA4C63C75B009306E20ABEFDE7_label_en-US" xlink:label="lab_us-gaap_RecordedUnconditionalPurchaseObligationDueAfterFifthYear_18F611EA4C63C75B009306E20ABEFDE7" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Recorded Unconditional Purchase Obligation Due after Fifth Year</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RecordedUnconditionalPurchaseObligationDueAfterFifthYear" xlink:label="loc_us-gaap_RecordedUnconditionalPurchaseObligationDueAfterFifthYear_18F611EA4C63C75B009306E20ABEFDE7" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RecordedUnconditionalPurchaseObligationDueAfterFifthYear_18F611EA4C63C75B009306E20ABEFDE7" xlink:to="lab_us-gaap_RecordedUnconditionalPurchaseObligationDueAfterFifthYear_18F611EA4C63C75B009306E20ABEFDE7" xlink:type="arc" />
    <link:label id="lab_us-gaap_OperatingLeasesRentExpenseNet_A5F15243113EB88CF37606E20ABEEAE7_terseLabel_en-US" xlink:label="lab_us-gaap_OperatingLeasesRentExpenseNet_A5F15243113EB88CF37606E20ABEEAE7" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Operating leases, expense</link:label>
    <link:label id="lab_us-gaap_OperatingLeasesRentExpenseNet_A5F15243113EB88CF37606E20ABEEAE7_label_en-US" xlink:label="lab_us-gaap_OperatingLeasesRentExpenseNet_A5F15243113EB88CF37606E20ABEEAE7" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Operating Leases, Rent Expense, Net</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_OperatingLeasesRentExpenseNet" xlink:label="loc_us-gaap_OperatingLeasesRentExpenseNet_A5F15243113EB88CF37606E20ABEEAE7" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OperatingLeasesRentExpenseNet_A5F15243113EB88CF37606E20ABEEAE7" xlink:to="lab_us-gaap_OperatingLeasesRentExpenseNet_A5F15243113EB88CF37606E20ABEEAE7" xlink:type="arc" />
    <link:label id="lab_us-gaap_OperatingLeasesFutureMinimumPaymentsDueCurrent_0A26E075CB89BAD6AE0206E20ABFE818_terseLabel_en-US" xlink:label="lab_us-gaap_OperatingLeasesFutureMinimumPaymentsDueCurrent_0A26E075CB89BAD6AE0206E20ABFE818" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Long-term operating leases, minimum annual rentals due in 2019</link:label>
    <link:label id="lab_us-gaap_OperatingLeasesFutureMinimumPaymentsDueCurrent_0A26E075CB89BAD6AE0206E20ABFE818_label_en-US" xlink:label="lab_us-gaap_OperatingLeasesFutureMinimumPaymentsDueCurrent_0A26E075CB89BAD6AE0206E20ABFE818" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Operating Leases, Future Minimum Payments Due, Next Twelve Months</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_OperatingLeasesFutureMinimumPaymentsDueCurrent" xlink:label="loc_us-gaap_OperatingLeasesFutureMinimumPaymentsDueCurrent_0A26E075CB89BAD6AE0206E20ABFE818" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OperatingLeasesFutureMinimumPaymentsDueCurrent_0A26E075CB89BAD6AE0206E20ABFE818" xlink:to="lab_us-gaap_OperatingLeasesFutureMinimumPaymentsDueCurrent_0A26E075CB89BAD6AE0206E20ABFE818" xlink:type="arc" />
    <link:label id="lab_us-gaap_OperatingLeasesFutureMinimumPaymentsDueInTwoYears_65DF9218C9783BD1A85706E20ABFF8DB_terseLabel_en-US" xlink:label="lab_us-gaap_OperatingLeasesFutureMinimumPaymentsDueInTwoYears_65DF9218C9783BD1A85706E20ABFF8DB" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Long-term operating leases, minimum annual rentals due in 2020</link:label>
    <link:label id="lab_us-gaap_OperatingLeasesFutureMinimumPaymentsDueInTwoYears_65DF9218C9783BD1A85706E20ABFF8DB_label_en-US" xlink:label="lab_us-gaap_OperatingLeasesFutureMinimumPaymentsDueInTwoYears_65DF9218C9783BD1A85706E20ABFF8DB" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Operating Leases, Future Minimum Payments, Due in Two Years</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_OperatingLeasesFutureMinimumPaymentsDueInTwoYears" xlink:label="loc_us-gaap_OperatingLeasesFutureMinimumPaymentsDueInTwoYears_65DF9218C9783BD1A85706E20ABFF8DB" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OperatingLeasesFutureMinimumPaymentsDueInTwoYears_65DF9218C9783BD1A85706E20ABFF8DB" xlink:to="lab_us-gaap_OperatingLeasesFutureMinimumPaymentsDueInTwoYears_65DF9218C9783BD1A85706E20ABFF8DB" xlink:type="arc" />
    <link:label id="lab_us-gaap_OperatingLeasesFutureMinimumPaymentsDueInThreeYears_34CFCBABC6C59C48C9A206E20ABFCD59_terseLabel_en-US" xlink:label="lab_us-gaap_OperatingLeasesFutureMinimumPaymentsDueInThreeYears_34CFCBABC6C59C48C9A206E20ABFCD59" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Long-term operating leases, minimum annual rentals due in 2021</link:label>
    <link:label id="lab_us-gaap_OperatingLeasesFutureMinimumPaymentsDueInThreeYears_34CFCBABC6C59C48C9A206E20ABFCD59_label_en-US" xlink:label="lab_us-gaap_OperatingLeasesFutureMinimumPaymentsDueInThreeYears_34CFCBABC6C59C48C9A206E20ABFCD59" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Operating Leases, Future Minimum Payments, Due in Three Years</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_OperatingLeasesFutureMinimumPaymentsDueInThreeYears" xlink:label="loc_us-gaap_OperatingLeasesFutureMinimumPaymentsDueInThreeYears_34CFCBABC6C59C48C9A206E20ABFCD59" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OperatingLeasesFutureMinimumPaymentsDueInThreeYears_34CFCBABC6C59C48C9A206E20ABFCD59" xlink:to="lab_us-gaap_OperatingLeasesFutureMinimumPaymentsDueInThreeYears_34CFCBABC6C59C48C9A206E20ABFCD59" xlink:type="arc" />
    <link:label id="lab_us-gaap_OperatingLeasesFutureMinimumPaymentsDueInFourYears_D3299E830776A273F85306E20ABFA079_terseLabel_en-US" xlink:label="lab_us-gaap_OperatingLeasesFutureMinimumPaymentsDueInFourYears_D3299E830776A273F85306E20ABFA079" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Long-term operating leases, minimum annual rentals due in 2022</link:label>
    <link:label id="lab_us-gaap_OperatingLeasesFutureMinimumPaymentsDueInFourYears_D3299E830776A273F85306E20ABFA079_label_en-US" xlink:label="lab_us-gaap_OperatingLeasesFutureMinimumPaymentsDueInFourYears_D3299E830776A273F85306E20ABFA079" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Operating Leases, Future Minimum Payments, Due in Four Years</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_OperatingLeasesFutureMinimumPaymentsDueInFourYears" xlink:label="loc_us-gaap_OperatingLeasesFutureMinimumPaymentsDueInFourYears_D3299E830776A273F85306E20ABFA079" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OperatingLeasesFutureMinimumPaymentsDueInFourYears_D3299E830776A273F85306E20ABFA079" xlink:to="lab_us-gaap_OperatingLeasesFutureMinimumPaymentsDueInFourYears_D3299E830776A273F85306E20ABFA079" xlink:type="arc" />
    <link:label id="lab_us-gaap_OperatingLeasesFutureMinimumPaymentsDueInFiveYears_00C190545573A2A394B506E20ABF99A8_terseLabel_en-US" xlink:label="lab_us-gaap_OperatingLeasesFutureMinimumPaymentsDueInFiveYears_00C190545573A2A394B506E20ABF99A8" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Long-term operating leases, minimum annual rentals due in 2023</link:label>
    <link:label id="lab_us-gaap_OperatingLeasesFutureMinimumPaymentsDueInFiveYears_00C190545573A2A394B506E20ABF99A8_label_en-US" xlink:label="lab_us-gaap_OperatingLeasesFutureMinimumPaymentsDueInFiveYears_00C190545573A2A394B506E20ABF99A8" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Operating Leases, Future Minimum Payments, Due in Five Years</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_OperatingLeasesFutureMinimumPaymentsDueInFiveYears" xlink:label="loc_us-gaap_OperatingLeasesFutureMinimumPaymentsDueInFiveYears_00C190545573A2A394B506E20ABF99A8" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OperatingLeasesFutureMinimumPaymentsDueInFiveYears_00C190545573A2A394B506E20ABF99A8" xlink:to="lab_us-gaap_OperatingLeasesFutureMinimumPaymentsDueInFiveYears_00C190545573A2A394B506E20ABF99A8" xlink:type="arc" />
    <link:label id="lab_us-gaap_OperatingLeasesFutureMinimumPaymentsDueThereafter_6A7A6754ECCE57AD588206E20ABFDAA9_terseLabel_en-US" xlink:label="lab_us-gaap_OperatingLeasesFutureMinimumPaymentsDueThereafter_6A7A6754ECCE57AD588206E20ABFDAA9" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Long-term operating leases, minimum annual rentals due thereafter</link:label>
    <link:label id="lab_us-gaap_OperatingLeasesFutureMinimumPaymentsDueThereafter_6A7A6754ECCE57AD588206E20ABFDAA9_label_en-US" xlink:label="lab_us-gaap_OperatingLeasesFutureMinimumPaymentsDueThereafter_6A7A6754ECCE57AD588206E20ABFDAA9" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Operating Leases, Future Minimum Payments, Due Thereafter</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_OperatingLeasesFutureMinimumPaymentsDueThereafter" xlink:label="loc_us-gaap_OperatingLeasesFutureMinimumPaymentsDueThereafter_6A7A6754ECCE57AD588206E20ABFDAA9" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OperatingLeasesFutureMinimumPaymentsDueThereafter_6A7A6754ECCE57AD588206E20ABFDAA9" xlink:to="lab_us-gaap_OperatingLeasesFutureMinimumPaymentsDueThereafter_6A7A6754ECCE57AD588206E20ABFDAA9" xlink:type="arc" />
    <link:label id="lab_us-gaap_GuaranteeObligationsCurrentCarryingValue_A81162231F4062B8589C06E20ABFD85B_terseLabel_en-US" xlink:label="lab_us-gaap_GuaranteeObligationsCurrentCarryingValue_A81162231F4062B8589C06E20ABFD85B" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Guarantees of third party related to project financing</link:label>
    <link:label id="lab_us-gaap_GuaranteeObligationsCurrentCarryingValue_A81162231F4062B8589C06E20ABFD85B_label_en-US" xlink:label="lab_us-gaap_GuaranteeObligationsCurrentCarryingValue_A81162231F4062B8589C06E20ABFD85B" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Guarantor Obligations, Current Carrying Value</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_GuaranteeObligationsCurrentCarryingValue" xlink:label="loc_us-gaap_GuaranteeObligationsCurrentCarryingValue_A81162231F4062B8589C06E20ABFD85B" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_GuaranteeObligationsCurrentCarryingValue_A81162231F4062B8589C06E20ABFD85B" xlink:to="lab_us-gaap_GuaranteeObligationsCurrentCarryingValue_A81162231F4062B8589C06E20ABFD85B" xlink:type="arc" />
    <link:label id="lab_us-gaap_GuaranteesFairValueDisclosure_E3B795D2243FCF77588A06E20AC0BCD6_terseLabel_en-US" xlink:label="lab_us-gaap_GuaranteesFairValueDisclosure_E3B795D2243FCF77588A06E20AC0BCD6" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Combined fair value of guarantees</link:label>
    <link:label id="lab_us-gaap_GuaranteesFairValueDisclosure_E3B795D2243FCF77588A06E20AC0BCD6_label_en-US" xlink:label="lab_us-gaap_GuaranteesFairValueDisclosure_E3B795D2243FCF77588A06E20AC0BCD6" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Guarantees, Fair Value Disclosure</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_GuaranteesFairValueDisclosure" xlink:label="loc_us-gaap_GuaranteesFairValueDisclosure_E3B795D2243FCF77588A06E20AC0BCD6" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_GuaranteesFairValueDisclosure_E3B795D2243FCF77588A06E20AC0BCD6" xlink:to="lab_us-gaap_GuaranteesFairValueDisclosure_E3B795D2243FCF77588A06E20AC0BCD6" xlink:type="arc" />
    <link:label id="lab_arnc_NumberOfLongTermEnergySupplyAgreements_4038C8DBA699DEED81F406E20AC060D4_terseLabel_en-US" xlink:label="lab_arnc_NumberOfLongTermEnergySupplyAgreements_4038C8DBA699DEED81F406E20AC060D4" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Number of long term energy supply agreements</link:label>
    <link:label id="lab_arnc_NumberOfLongTermEnergySupplyAgreements_4038C8DBA699DEED81F406E20AC060D4_label_en-US" xlink:label="lab_arnc_NumberOfLongTermEnergySupplyAgreements_4038C8DBA699DEED81F406E20AC060D4" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Number Of Long Term Energy Supply Agreements</link:label>
    <link:label id="lab_arnc_NumberOfLongTermEnergySupplyAgreements_4038C8DBA699DEED81F406E20AC060D4_documentation_en-US" xlink:label="lab_arnc_NumberOfLongTermEnergySupplyAgreements_4038C8DBA699DEED81F406E20AC060D4" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Number Of Long Term Energy Supply Agreements</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_NumberOfLongTermEnergySupplyAgreements" xlink:label="loc_arnc_NumberOfLongTermEnergySupplyAgreements_4038C8DBA699DEED81F406E20AC060D4" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_NumberOfLongTermEnergySupplyAgreements_4038C8DBA699DEED81F406E20AC060D4" xlink:to="lab_arnc_NumberOfLongTermEnergySupplyAgreements_4038C8DBA699DEED81F406E20AC060D4" xlink:type="arc" />
    <link:label id="lab_arnc_NumberofAgreementsTerminated_EFFEA2569513855BE73006E20AC5D7AE_terseLabel_en-US" xlink:label="lab_arnc_NumberofAgreementsTerminated_EFFEA2569513855BE73006E20AC5D7AE" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Number of agreements terminated</link:label>
    <link:label id="lab_arnc_NumberofAgreementsTerminated_EFFEA2569513855BE73006E20AC5D7AE_label_en-US" xlink:label="lab_arnc_NumberofAgreementsTerminated_EFFEA2569513855BE73006E20AC5D7AE" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Number of Agreements Terminated</link:label>
    <link:label id="lab_arnc_NumberofAgreementsTerminated_EFFEA2569513855BE73006E20AC5D7AE_documentation_en-US" xlink:label="lab_arnc_NumberofAgreementsTerminated_EFFEA2569513855BE73006E20AC5D7AE" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Number of Agreements Terminated</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_NumberofAgreementsTerminated" xlink:label="loc_arnc_NumberofAgreementsTerminated_EFFEA2569513855BE73006E20AC5D7AE" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_NumberofAgreementsTerminated_EFFEA2569513855BE73006E20AC5D7AE" xlink:to="lab_arnc_NumberofAgreementsTerminated_EFFEA2569513855BE73006E20AC5D7AE" xlink:type="arc" />
    <link:label id="lab_us-gaap_GuaranteeObligationsMaximumExposure_28ED194299A8604544F706E20AC5B838_terseLabel_en-US" xlink:label="lab_us-gaap_GuaranteeObligationsMaximumExposure_28ED194299A8604544F706E20AC5B838" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Guarantees of third party related to project financing</link:label>
    <link:label id="lab_us-gaap_GuaranteeObligationsMaximumExposure_28ED194299A8604544F706E20AC5B838_label_en-US" xlink:label="lab_us-gaap_GuaranteeObligationsMaximumExposure_28ED194299A8604544F706E20AC5B838" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Guarantor Obligations, Maximum Exposure, Undiscounted</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_GuaranteeObligationsMaximumExposure" xlink:label="loc_us-gaap_GuaranteeObligationsMaximumExposure_28ED194299A8604544F706E20AC5B838" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_GuaranteeObligationsMaximumExposure_28ED194299A8604544F706E20AC5B838" xlink:to="lab_us-gaap_GuaranteeObligationsMaximumExposure_28ED194299A8604544F706E20AC5B838" xlink:type="arc" />
    <link:label id="lab_us-gaap_LongtermPurchaseCommitmentPeriod_BBF9721206911777D67106E20AC6ECE0_terseLabel_en-US" xlink:label="lab_us-gaap_LongtermPurchaseCommitmentPeriod_BBF9721206911777D67106E20AC6ECE0" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Long-term purchase commitment, period</link:label>
    <link:label id="lab_us-gaap_LongtermPurchaseCommitmentPeriod_BBF9721206911777D67106E20AC6ECE0_label_en-US" xlink:label="lab_us-gaap_LongtermPurchaseCommitmentPeriod_BBF9721206911777D67106E20AC6ECE0" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Long-term Purchase Commitment, Period</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_LongtermPurchaseCommitmentPeriod" xlink:label="loc_us-gaap_LongtermPurchaseCommitmentPeriod_BBF9721206911777D67106E20AC6ECE0" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LongtermPurchaseCommitmentPeriod_BBF9721206911777D67106E20AC6ECE0" xlink:to="lab_us-gaap_LongtermPurchaseCommitmentPeriod_BBF9721206911777D67106E20AC6ECE0" xlink:type="arc" />
    <link:label id="lab_arnc_GuaranteesOfThirdPartyObligationsRelatedToProjectFinancing_985ABC268E62AE41C0AC06E20AC62FBB_terseLabel_en-US" xlink:label="lab_arnc_GuaranteesOfThirdPartyObligationsRelatedToProjectFinancing_985ABC268E62AE41C0AC06E20AC62FBB" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Guarantees of third party related to project financing</link:label>
    <link:label id="lab_arnc_GuaranteesOfThirdPartyObligationsRelatedToProjectFinancing_985ABC268E62AE41C0AC06E20AC62FBB_label_en-US" xlink:label="lab_arnc_GuaranteesOfThirdPartyObligationsRelatedToProjectFinancing_985ABC268E62AE41C0AC06E20AC62FBB" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Guarantees Of Third Party Obligations Related To Project Financing</link:label>
    <link:label id="lab_arnc_GuaranteesOfThirdPartyObligationsRelatedToProjectFinancing_985ABC268E62AE41C0AC06E20AC62FBB_documentation_en-US" xlink:label="lab_arnc_GuaranteesOfThirdPartyObligationsRelatedToProjectFinancing_985ABC268E62AE41C0AC06E20AC62FBB" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Guarantees of third party obligations related to project financing.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_GuaranteesOfThirdPartyObligationsRelatedToProjectFinancing" xlink:label="loc_arnc_GuaranteesOfThirdPartyObligationsRelatedToProjectFinancing_985ABC268E62AE41C0AC06E20AC62FBB" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_GuaranteesOfThirdPartyObligationsRelatedToProjectFinancing_985ABC268E62AE41C0AC06E20AC62FBB" xlink:to="lab_arnc_GuaranteesOfThirdPartyObligationsRelatedToProjectFinancing_985ABC268E62AE41C0AC06E20AC62FBB" xlink:type="arc" />
    <link:label id="lab_arnc_InsurancePolicyDuration_2B1E0413E5EAB0B455E406E20AC6C223_terseLabel_en-US" xlink:label="lab_arnc_InsurancePolicyDuration_2B1E0413E5EAB0B455E406E20AC6C223" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Insurance policy duration</link:label>
    <link:label id="lab_arnc_InsurancePolicyDuration_2B1E0413E5EAB0B455E406E20AC6C223_label_en-US" xlink:label="lab_arnc_InsurancePolicyDuration_2B1E0413E5EAB0B455E406E20AC6C223" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Insurance Policy Duration</link:label>
    <link:label id="lab_arnc_InsurancePolicyDuration_2B1E0413E5EAB0B455E406E20AC6C223_documentation_en-US" xlink:label="lab_arnc_InsurancePolicyDuration_2B1E0413E5EAB0B455E406E20AC6C223" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Insurance Policy Duration</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_InsurancePolicyDuration" xlink:label="loc_arnc_InsurancePolicyDuration_2B1E0413E5EAB0B455E406E20AC6C223" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_InsurancePolicyDuration_2B1E0413E5EAB0B455E406E20AC6C223" xlink:to="lab_arnc_InsurancePolicyDuration_2B1E0413E5EAB0B455E406E20AC6C223" xlink:type="arc" />
    <link:label id="lab_arnc_MalpracticeInsuranceThirdPartyCoverageMaximumCoverage_62BD44DF1D6A147CA67106E20AC69252_terseLabel_en-US" xlink:label="lab_arnc_MalpracticeInsuranceThirdPartyCoverageMaximumCoverage_62BD44DF1D6A147CA67106E20AC69252" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Insurance policy limit</link:label>
    <link:label id="lab_arnc_MalpracticeInsuranceThirdPartyCoverageMaximumCoverage_62BD44DF1D6A147CA67106E20AC69252_label_en-US" xlink:label="lab_arnc_MalpracticeInsuranceThirdPartyCoverageMaximumCoverage_62BD44DF1D6A147CA67106E20AC69252" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Malpractice Insurance, Third Party Coverage, Maximum Coverage</link:label>
    <link:label id="lab_arnc_MalpracticeInsuranceThirdPartyCoverageMaximumCoverage_62BD44DF1D6A147CA67106E20AC69252_documentation_en-US" xlink:label="lab_arnc_MalpracticeInsuranceThirdPartyCoverageMaximumCoverage_62BD44DF1D6A147CA67106E20AC69252" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Malpractice Insurance, Third Party Coverage, Maximum Coverage</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_MalpracticeInsuranceThirdPartyCoverageMaximumCoverage" xlink:label="loc_arnc_MalpracticeInsuranceThirdPartyCoverageMaximumCoverage_62BD44DF1D6A147CA67106E20AC69252" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_MalpracticeInsuranceThirdPartyCoverageMaximumCoverage_62BD44DF1D6A147CA67106E20AC69252" xlink:to="lab_arnc_MalpracticeInsuranceThirdPartyCoverageMaximumCoverage_62BD44DF1D6A147CA67106E20AC69252" xlink:type="arc" />
    <link:label id="lab_us-gaap_LongTermDebt_69459B874A92CFD5460306E20AC6FF0B_terseLabel_en-US" xlink:label="lab_us-gaap_LongTermDebt_69459B874A92CFD5460306E20AC6FF0B" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Letters of credit</link:label>
    <link:label id="lab_us-gaap_LongTermDebt_69459B874A92CFD5460306E20AC6FF0B_label_en-US" xlink:label="lab_us-gaap_LongTermDebt_69459B874A92CFD5460306E20AC6FF0B" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Long-term Debt</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_LongTermDebt" xlink:label="loc_us-gaap_LongTermDebt_69459B874A92CFD5460306E20AC6FF0B" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LongTermDebt_69459B874A92CFD5460306E20AC6FF0B" xlink:to="lab_us-gaap_LongTermDebt_69459B874A92CFD5460306E20AC6FF0B" xlink:type="arc" />
    <link:label id="lab_us-gaap_LettersOfCreditOutstandingAmount_B10C4C965756A27F02C306E20AC6E4C8_terseLabel_en-US" xlink:label="lab_us-gaap_LettersOfCreditOutstandingAmount_B10C4C965756A27F02C306E20AC6E4C8" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Letters of credit, total amount committed</link:label>
    <link:label id="lab_us-gaap_LettersOfCreditOutstandingAmount_B10C4C965756A27F02C306E20AC6E4C8_label_en-US" xlink:label="lab_us-gaap_LettersOfCreditOutstandingAmount_B10C4C965756A27F02C306E20AC6E4C8" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Letters of Credit Outstanding, Amount</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_LettersOfCreditOutstandingAmount" xlink:label="loc_us-gaap_LettersOfCreditOutstandingAmount_B10C4C965756A27F02C306E20AC6E4C8" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LettersOfCreditOutstandingAmount_B10C4C965756A27F02C306E20AC6E4C8" xlink:to="lab_us-gaap_LettersOfCreditOutstandingAmount_B10C4C965756A27F02C306E20AC6E4C8" xlink:type="arc" />
    <link:label id="lab_arnc_AmountCommittedUnderOutstandingSuretyBonds_8EE4F9F1BF0A0933111506E20AC66614_terseLabel_en-US" xlink:label="lab_arnc_AmountCommittedUnderOutstandingSuretyBonds_8EE4F9F1BF0A0933111506E20AC66614" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Total amount committed under outstanding surety bonds</link:label>
    <link:label id="lab_arnc_AmountCommittedUnderOutstandingSuretyBonds_8EE4F9F1BF0A0933111506E20AC66614_label_en-US" xlink:label="lab_arnc_AmountCommittedUnderOutstandingSuretyBonds_8EE4F9F1BF0A0933111506E20AC66614" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Amount Committed Under Outstanding Surety Bonds</link:label>
    <link:label id="lab_arnc_AmountCommittedUnderOutstandingSuretyBonds_8EE4F9F1BF0A0933111506E20AC66614_documentation_en-US" xlink:label="lab_arnc_AmountCommittedUnderOutstandingSuretyBonds_8EE4F9F1BF0A0933111506E20AC66614" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Amount Committed Under Outstanding Surety Bonds</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_AmountCommittedUnderOutstandingSuretyBonds" xlink:label="loc_arnc_AmountCommittedUnderOutstandingSuretyBonds_8EE4F9F1BF0A0933111506E20AC66614" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_AmountCommittedUnderOutstandingSuretyBonds_8EE4F9F1BF0A0933111506E20AC66614" xlink:to="lab_arnc_AmountCommittedUnderOutstandingSuretyBonds_8EE4F9F1BF0A0933111506E20AC66614" xlink:type="arc" />
    <link:label id="lab_arnc_SeparationAndDistributionAgreementSuretyBondsAmountOutstanding_2B6BBD09DCC7DC5182A306E20AC74E88_terseLabel_en-US" xlink:label="lab_arnc_SeparationAndDistributionAgreementSuretyBondsAmountOutstanding_2B6BBD09DCC7DC5182A306E20AC74E88" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Amount of outstanding surety bonds relating to these liabilities</link:label>
    <link:label id="lab_arnc_SeparationAndDistributionAgreementSuretyBondsAmountOutstanding_2B6BBD09DCC7DC5182A306E20AC74E88_label_en-US" xlink:label="lab_arnc_SeparationAndDistributionAgreementSuretyBondsAmountOutstanding_2B6BBD09DCC7DC5182A306E20AC74E88" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Separation And Distribution Agreement, Surety Bonds, Amount Outstanding</link:label>
    <link:label id="lab_arnc_SeparationAndDistributionAgreementSuretyBondsAmountOutstanding_2B6BBD09DCC7DC5182A306E20AC74E88_documentation_en-US" xlink:label="lab_arnc_SeparationAndDistributionAgreementSuretyBondsAmountOutstanding_2B6BBD09DCC7DC5182A306E20AC74E88" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Separation And Distribution Agreement, Surety Bonds, Amount Outstanding</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_SeparationAndDistributionAgreementSuretyBondsAmountOutstanding" xlink:label="loc_arnc_SeparationAndDistributionAgreementSuretyBondsAmountOutstanding_2B6BBD09DCC7DC5182A306E20AC74E88" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_SeparationAndDistributionAgreementSuretyBondsAmountOutstanding_2B6BBD09DCC7DC5182A306E20AC74E88" xlink:to="lab_arnc_SeparationAndDistributionAgreementSuretyBondsAmountOutstanding_2B6BBD09DCC7DC5182A306E20AC74E88" xlink:type="arc" />
    <link:label id="lab_us-gaap_EarningsPerShareTextBlock_997EF5D0BCA67BF672457C362DB108B4_terseLabel_en-US" xlink:label="lab_us-gaap_EarningsPerShareTextBlock_997EF5D0BCA67BF672457C362DB108B4" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Earnings Per Share</link:label>
    <link:label id="lab_us-gaap_EarningsPerShareTextBlock_997EF5D0BCA67BF672457C362DB108B4_label_en-US" xlink:label="lab_us-gaap_EarningsPerShareTextBlock_997EF5D0BCA67BF672457C362DB108B4" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Earnings Per Share [Text Block]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_EarningsPerShareTextBlock" xlink:label="loc_us-gaap_EarningsPerShareTextBlock_997EF5D0BCA67BF672457C362DB108B4" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_EarningsPerShareTextBlock_997EF5D0BCA67BF672457C362DB108B4" xlink:to="lab_us-gaap_EarningsPerShareTextBlock_997EF5D0BCA67BF672457C362DB108B4" xlink:type="arc" />
    <link:label id="lab_arnc_ScheduleOfInterestCostComponentsTextBlock_71EA2FEC2CA1CEFF126F7C362FA3D079_terseLabel_en-US" xlink:label="lab_arnc_ScheduleOfInterestCostComponentsTextBlock_71EA2FEC2CA1CEFF126F7C362FA3D079" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Schedule of Interest Cost Components</link:label>
    <link:label id="lab_arnc_ScheduleOfInterestCostComponentsTextBlock_71EA2FEC2CA1CEFF126F7C362FA3D079_label_en-US" xlink:label="lab_arnc_ScheduleOfInterestCostComponentsTextBlock_71EA2FEC2CA1CEFF126F7C362FA3D079" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Schedule Of Interest Cost Components [Text Block]</link:label>
    <link:label id="lab_arnc_ScheduleOfInterestCostComponentsTextBlock_71EA2FEC2CA1CEFF126F7C362FA3D079_documentation_en-US" xlink:label="lab_arnc_ScheduleOfInterestCostComponentsTextBlock_71EA2FEC2CA1CEFF126F7C362FA3D079" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Schedule of Interest Cost Components [Text Block]</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_ScheduleOfInterestCostComponentsTextBlock" xlink:label="loc_arnc_ScheduleOfInterestCostComponentsTextBlock_71EA2FEC2CA1CEFF126F7C362FA3D079" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_ScheduleOfInterestCostComponentsTextBlock_71EA2FEC2CA1CEFF126F7C362FA3D079" xlink:to="lab_arnc_ScheduleOfInterestCostComponentsTextBlock_71EA2FEC2CA1CEFF126F7C362FA3D079" xlink:type="arc" />
    <link:label id="lab_us-gaap_ScheduleOfPropertyPlantAndEquipmentTable_983F6F8BD517CEFAD477E244A9BE21D2_terseLabel_en-US" xlink:label="lab_us-gaap_ScheduleOfPropertyPlantAndEquipmentTable_983F6F8BD517CEFAD477E244A9BE21D2" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Property, Plant and Equipment [Table]</link:label>
    <link:label id="lab_us-gaap_ScheduleOfPropertyPlantAndEquipmentTable_983F6F8BD517CEFAD477E244A9BE21D2_label_en-US" xlink:label="lab_us-gaap_ScheduleOfPropertyPlantAndEquipmentTable_983F6F8BD517CEFAD477E244A9BE21D2" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Property, Plant and Equipment [Table]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ScheduleOfPropertyPlantAndEquipmentTable" xlink:label="loc_us-gaap_ScheduleOfPropertyPlantAndEquipmentTable_983F6F8BD517CEFAD477E244A9BE21D2" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfPropertyPlantAndEquipmentTable_983F6F8BD517CEFAD477E244A9BE21D2" xlink:to="lab_us-gaap_ScheduleOfPropertyPlantAndEquipmentTable_983F6F8BD517CEFAD477E244A9BE21D2" xlink:type="arc" />
    <link:label id="lab_us-gaap_MaterialReconcilingItemsMember_21BE22F7D3D11AFCFBA7E244A9BEA48E_terseLabel_en-US" xlink:label="lab_us-gaap_MaterialReconcilingItemsMember_21BE22F7D3D11AFCFBA7E244A9BEA48E" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Other</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_MaterialReconcilingItemsMember" xlink:label="loc_us-gaap_MaterialReconcilingItemsMember_21BE22F7D3D11AFCFBA7E244A9BEA48E" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_MaterialReconcilingItemsMember_21BE22F7D3D11AFCFBA7E244A9BEA48E" xlink:to="lab_us-gaap_MaterialReconcilingItemsMember_21BE22F7D3D11AFCFBA7E244A9BEA48E" xlink:type="arc" />
    <link:label id="lab_us-gaap_ReportingUnitAxis_F87ADF59F98C624157ABE244A9BE9FAE_terseLabel_en-US" xlink:label="lab_us-gaap_ReportingUnitAxis_F87ADF59F98C624157ABE244A9BE9FAE" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Reporting Unit [Axis]</link:label>
    <link:label id="lab_us-gaap_ReportingUnitAxis_F87ADF59F98C624157ABE244A9BE9FAE_label_en-US" xlink:label="lab_us-gaap_ReportingUnitAxis_F87ADF59F98C624157ABE244A9BE9FAE" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Reporting Unit [Axis]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ReportingUnitAxis" xlink:label="loc_us-gaap_ReportingUnitAxis_F87ADF59F98C624157ABE244A9BE9FAE" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ReportingUnitAxis_F87ADF59F98C624157ABE244A9BE9FAE" xlink:to="lab_us-gaap_ReportingUnitAxis_F87ADF59F98C624157ABE244A9BE9FAE" xlink:type="arc" />
    <link:label id="lab_us-gaap_ReportingUnitDomain_6590A7F8581764EA6C70E244A9BED0FA_terseLabel_en-US" xlink:label="lab_us-gaap_ReportingUnitDomain_6590A7F8581764EA6C70E244A9BED0FA" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Reporting Unit [Domain]</link:label>
    <link:label id="lab_us-gaap_ReportingUnitDomain_6590A7F8581764EA6C70E244A9BED0FA_label_en-US" xlink:label="lab_us-gaap_ReportingUnitDomain_6590A7F8581764EA6C70E244A9BED0FA" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Reporting Unit [Domain]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ReportingUnitDomain" xlink:label="loc_us-gaap_ReportingUnitDomain_6590A7F8581764EA6C70E244A9BED0FA" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ReportingUnitDomain_6590A7F8581764EA6C70E244A9BED0FA" xlink:to="lab_us-gaap_ReportingUnitDomain_6590A7F8581764EA6C70E244A9BED0FA" xlink:type="arc" />
    <link:label id="lab_arnc_ArconicEnginesMember_3F36C70F3C8E5B2058DBE244A9C2C6CE_terseLabel_en-US" xlink:label="lab_arnc_ArconicEnginesMember_3F36C70F3C8E5B2058DBE244A9C2C6CE" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Arconic Engines</link:label>
    <link:label id="lab_arnc_ArconicEnginesMember_3F36C70F3C8E5B2058DBE244A9C2C6CE_label_en-US" xlink:label="lab_arnc_ArconicEnginesMember_3F36C70F3C8E5B2058DBE244A9C2C6CE" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Arconic Engines [Member]</link:label>
    <link:label id="lab_arnc_ArconicEnginesMember_3F36C70F3C8E5B2058DBE244A9C2C6CE_documentation_en-US" xlink:label="lab_arnc_ArconicEnginesMember_3F36C70F3C8E5B2058DBE244A9C2C6CE" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Arconic Engines [Member]</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_ArconicEnginesMember" xlink:label="loc_arnc_ArconicEnginesMember_3F36C70F3C8E5B2058DBE244A9C2C6CE" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_ArconicEnginesMember_3F36C70F3C8E5B2058DBE244A9C2C6CE" xlink:to="lab_arnc_ArconicEnginesMember_3F36C70F3C8E5B2058DBE244A9C2C6CE" xlink:type="arc" />
    <link:label id="lab_us-gaap_PropertyPlantAndEquipmentByTypeAxis_9FE155C25FFC7D8D5BE5E244A9C2E281_terseLabel_en-US" xlink:label="lab_us-gaap_PropertyPlantAndEquipmentByTypeAxis_9FE155C25FFC7D8D5BE5E244A9C2E281" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Property, Plant and Equipment, Type [Axis]</link:label>
    <link:label id="lab_us-gaap_PropertyPlantAndEquipmentByTypeAxis_9FE155C25FFC7D8D5BE5E244A9C2E281_label_en-US" xlink:label="lab_us-gaap_PropertyPlantAndEquipmentByTypeAxis_9FE155C25FFC7D8D5BE5E244A9C2E281" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Property, Plant and Equipment, Type [Axis]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PropertyPlantAndEquipmentByTypeAxis" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentByTypeAxis_9FE155C25FFC7D8D5BE5E244A9C2E281" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentByTypeAxis_9FE155C25FFC7D8D5BE5E244A9C2E281" xlink:to="lab_us-gaap_PropertyPlantAndEquipmentByTypeAxis_9FE155C25FFC7D8D5BE5E244A9C2E281" xlink:type="arc" />
    <link:label id="lab_us-gaap_PropertyPlantAndEquipmentTypeDomain_8028E8D83D0B30FE22D1E244A9C24F74_terseLabel_en-US" xlink:label="lab_us-gaap_PropertyPlantAndEquipmentTypeDomain_8028E8D83D0B30FE22D1E244A9C24F74" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Property, Plant and Equipment, Type [Domain]</link:label>
    <link:label id="lab_us-gaap_PropertyPlantAndEquipmentTypeDomain_8028E8D83D0B30FE22D1E244A9C24F74_label_en-US" xlink:label="lab_us-gaap_PropertyPlantAndEquipmentTypeDomain_8028E8D83D0B30FE22D1E244A9C24F74" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Property, Plant and Equipment, Type [Domain]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PropertyPlantAndEquipmentTypeDomain" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_8028E8D83D0B30FE22D1E244A9C24F74" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_8028E8D83D0B30FE22D1E244A9C24F74" xlink:to="lab_us-gaap_PropertyPlantAndEquipmentTypeDomain_8028E8D83D0B30FE22D1E244A9C24F74" xlink:type="arc" />
    <link:label id="lab_us-gaap_LandMember_99331C2B346CD7614E70E244A9C24781_terseLabel_en-US" xlink:label="lab_us-gaap_LandMember_99331C2B346CD7614E70E244A9C24781" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Land and land rights</link:label>
    <link:label id="lab_us-gaap_LandMember_99331C2B346CD7614E70E244A9C24781_label_en-US" xlink:label="lab_us-gaap_LandMember_99331C2B346CD7614E70E244A9C24781" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Land [Member]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_LandMember" xlink:label="loc_us-gaap_LandMember_99331C2B346CD7614E70E244A9C24781" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LandMember_99331C2B346CD7614E70E244A9C24781" xlink:to="lab_us-gaap_LandMember_99331C2B346CD7614E70E244A9C24781" xlink:type="arc" />
    <link:label id="lab_us-gaap_ManufacturingFacilityMember_B921FEB2D60FA47B1DC1E244A9C2C0DE_terseLabel_en-US" xlink:label="lab_us-gaap_ManufacturingFacilityMember_B921FEB2D60FA47B1DC1E244A9C2C0DE" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Structures</link:label>
    <link:label id="lab_us-gaap_ManufacturingFacilityMember_B921FEB2D60FA47B1DC1E244A9C2C0DE_label_en-US" xlink:label="lab_us-gaap_ManufacturingFacilityMember_B921FEB2D60FA47B1DC1E244A9C2C0DE" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Manufacturing Facility [Member]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ManufacturingFacilityMember" xlink:label="loc_us-gaap_ManufacturingFacilityMember_B921FEB2D60FA47B1DC1E244A9C2C0DE" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ManufacturingFacilityMember_B921FEB2D60FA47B1DC1E244A9C2C0DE" xlink:to="lab_us-gaap_ManufacturingFacilityMember_B921FEB2D60FA47B1DC1E244A9C2C0DE" xlink:type="arc" />
    <link:label id="lab_us-gaap_MachineryAndEquipmentMember_D1BE61CA71888D0A1BC4E244A9C2F2D2_verboseLabel_en-US" xlink:label="lab_us-gaap_MachineryAndEquipmentMember_D1BE61CA71888D0A1BC4E244A9C2F2D2" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Machinery and equipment:</link:label>
    <link:label id="lab_us-gaap_MachineryAndEquipmentMember_D1BE61CA71888D0A1BC4E244A9C2F2D2_label_en-US" xlink:label="lab_us-gaap_MachineryAndEquipmentMember_D1BE61CA71888D0A1BC4E244A9C2F2D2" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Machinery and Equipment [Member]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_MachineryAndEquipmentMember" xlink:label="loc_us-gaap_MachineryAndEquipmentMember_D1BE61CA71888D0A1BC4E244A9C2F2D2" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_MachineryAndEquipmentMember_D1BE61CA71888D0A1BC4E244A9C2F2D2" xlink:to="lab_us-gaap_MachineryAndEquipmentMember_D1BE61CA71888D0A1BC4E244A9C2F2D2" xlink:type="arc" />
    <link:label id="lab_us-gaap_PropertyPlantAndEquipmentLineItems_59AF4FDD90D3792CA922E244A9C21288_terseLabel_en-US" xlink:label="lab_us-gaap_PropertyPlantAndEquipmentLineItems_59AF4FDD90D3792CA922E244A9C21288" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Property, Plant and Equipment [Line Items]</link:label>
    <link:label id="lab_us-gaap_PropertyPlantAndEquipmentLineItems_59AF4FDD90D3792CA922E244A9C21288_label_en-US" xlink:label="lab_us-gaap_PropertyPlantAndEquipmentLineItems_59AF4FDD90D3792CA922E244A9C21288" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Property, Plant and Equipment [Line Items]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PropertyPlantAndEquipmentLineItems" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentLineItems_59AF4FDD90D3792CA922E244A9C21288" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentLineItems_59AF4FDD90D3792CA922E244A9C21288" xlink:to="lab_us-gaap_PropertyPlantAndEquipmentLineItems_59AF4FDD90D3792CA922E244A9C21288" xlink:type="arc" />
    <link:label id="lab_us-gaap_NoncurrentAssets_572F2E69734127FB5B3AE244A9C2D9A4_terseLabel_en-US" xlink:label="lab_us-gaap_NoncurrentAssets_572F2E69734127FB5B3AE244A9C2D9A4" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Assets</link:label>
    <link:label id="lab_us-gaap_NoncurrentAssets_572F2E69734127FB5B3AE244A9C2D9A4_label_en-US" xlink:label="lab_us-gaap_NoncurrentAssets_572F2E69734127FB5B3AE244A9C2D9A4" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Long-Lived Assets</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_NoncurrentAssets" xlink:label="loc_us-gaap_NoncurrentAssets_572F2E69734127FB5B3AE244A9C2D9A4" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_NoncurrentAssets_572F2E69734127FB5B3AE244A9C2D9A4" xlink:to="lab_us-gaap_NoncurrentAssets_572F2E69734127FB5B3AE244A9C2D9A4" xlink:type="arc" />
    <link:label id="lab_us-gaap_PropertyPlantAndEquipmentGross_278110173D748102F00BE244A9C29EE3_terseLabel_en-US" xlink:label="lab_us-gaap_PropertyPlantAndEquipmentGross_278110173D748102F00BE244A9C29EE3" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Properties, plants, and equipment, gross</link:label>
    <link:label id="lab_us-gaap_PropertyPlantAndEquipmentGross_278110173D748102F00BE244A9C29EE3_label_en-US" xlink:label="lab_us-gaap_PropertyPlantAndEquipmentGross_278110173D748102F00BE244A9C29EE3" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Property, Plant and Equipment, Gross</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PropertyPlantAndEquipmentGross" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentGross_278110173D748102F00BE244A9C29EE3" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentGross_278110173D748102F00BE244A9C29EE3" xlink:to="lab_us-gaap_PropertyPlantAndEquipmentGross_278110173D748102F00BE244A9C29EE3" xlink:type="arc" />
    <link:label id="lab_us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment_28C097056C211CA358B1E244A9C297AE_terseLabel_en-US" xlink:label="lab_us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment_28C097056C211CA358B1E244A9C297AE" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Less: accumulated depreciation and amortization</link:label>
    <link:label id="lab_us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment_28C097056C211CA358B1E244A9C297AE_label_en-US" xlink:label="lab_us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment_28C097056C211CA358B1E244A9C297AE" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment" xlink:label="loc_us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment_28C097056C211CA358B1E244A9C297AE" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment_28C097056C211CA358B1E244A9C297AE" xlink:to="lab_us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment_28C097056C211CA358B1E244A9C297AE" xlink:type="arc" />
    <link:label id="lab_arnc_PropertiesPlantsAndEquipmentExcludingConstructionWorkInProgress_1D50B578175D081EFC06E244A9C22DB4_totalLabel_en-US" xlink:label="lab_arnc_PropertiesPlantsAndEquipmentExcludingConstructionWorkInProgress_1D50B578175D081EFC06E244A9C22DB4" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Properties plants and equipment excluding construction work in progress</link:label>
    <link:label id="lab_arnc_PropertiesPlantsAndEquipmentExcludingConstructionWorkInProgress_1D50B578175D081EFC06E244A9C22DB4_label_en-US" xlink:label="lab_arnc_PropertiesPlantsAndEquipmentExcludingConstructionWorkInProgress_1D50B578175D081EFC06E244A9C22DB4" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Properties Plants And Equipment Excluding Construction Work In Progress</link:label>
    <link:label id="lab_arnc_PropertiesPlantsAndEquipmentExcludingConstructionWorkInProgress_1D50B578175D081EFC06E244A9C22DB4_documentation_en-US" xlink:label="lab_arnc_PropertiesPlantsAndEquipmentExcludingConstructionWorkInProgress_1D50B578175D081EFC06E244A9C22DB4" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Properties plants and equipment excluding construction work in progress.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_PropertiesPlantsAndEquipmentExcludingConstructionWorkInProgress" xlink:label="loc_arnc_PropertiesPlantsAndEquipmentExcludingConstructionWorkInProgress_1D50B578175D081EFC06E244A9C22DB4" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_PropertiesPlantsAndEquipmentExcludingConstructionWorkInProgress_1D50B578175D081EFC06E244A9C22DB4" xlink:to="lab_arnc_PropertiesPlantsAndEquipmentExcludingConstructionWorkInProgress_1D50B578175D081EFC06E244A9C22DB4" xlink:type="arc" />
    <link:label id="lab_us-gaap_ConstructionInProgressGross_DD67DA9A19CB8B20C1C7E244A9C2DC19_terseLabel_en-US" xlink:label="lab_us-gaap_ConstructionInProgressGross_DD67DA9A19CB8B20C1C7E244A9C2DC19" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Construction work-in-progress</link:label>
    <link:label id="lab_us-gaap_ConstructionInProgressGross_DD67DA9A19CB8B20C1C7E244A9C2DC19_label_en-US" xlink:label="lab_us-gaap_ConstructionInProgressGross_DD67DA9A19CB8B20C1C7E244A9C2DC19" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Construction in Progress, Gross</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ConstructionInProgressGross" xlink:label="loc_us-gaap_ConstructionInProgressGross_DD67DA9A19CB8B20C1C7E244A9C2DC19" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ConstructionInProgressGross_DD67DA9A19CB8B20C1C7E244A9C2DC19" xlink:to="lab_us-gaap_ConstructionInProgressGross_DD67DA9A19CB8B20C1C7E244A9C2DC19" xlink:type="arc" />
    <link:label id="lab_us-gaap_PropertyPlantAndEquipmentNet_1C53186ACC931F73287DE244A9C2DB78_totalLabel_en-US" xlink:label="lab_us-gaap_PropertyPlantAndEquipmentNet_1C53186ACC931F73287DE244A9C2DB78" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Properties, plants, and equipment, net</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PropertyPlantAndEquipmentNet" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentNet_1C53186ACC931F73287DE244A9C2DB78" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentNet_1C53186ACC931F73287DE244A9C2DB78" xlink:to="lab_us-gaap_PropertyPlantAndEquipmentNet_1C53186ACC931F73287DE244A9C2DB78" xlink:type="arc" />
    <link:label id="lab_us-gaap_ReportingUnitPercentageOfFairValueInExcessOfCarryingAmount_9128E4C8DFEEA28BEBC7E244A9C28320_terseLabel_en-US" xlink:label="lab_us-gaap_ReportingUnitPercentageOfFairValueInExcessOfCarryingAmount_9128E4C8DFEEA28BEBC7E244A9C28320" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Percentage of fair value in excess of carrying amount</link:label>
    <link:label id="lab_us-gaap_ReportingUnitPercentageOfFairValueInExcessOfCarryingAmount_9128E4C8DFEEA28BEBC7E244A9C28320_label_en-US" xlink:label="lab_us-gaap_ReportingUnitPercentageOfFairValueInExcessOfCarryingAmount_9128E4C8DFEEA28BEBC7E244A9C28320" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Reporting Unit, Percentage of Fair Value in Excess of Carrying Amount</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ReportingUnitPercentageOfFairValueInExcessOfCarryingAmount" xlink:label="loc_us-gaap_ReportingUnitPercentageOfFairValueInExcessOfCarryingAmount_9128E4C8DFEEA28BEBC7E244A9C28320" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ReportingUnitPercentageOfFairValueInExcessOfCarryingAmount_9128E4C8DFEEA28BEBC7E244A9C28320" xlink:to="lab_us-gaap_ReportingUnitPercentageOfFairValueInExcessOfCarryingAmount_9128E4C8DFEEA28BEBC7E244A9C28320" xlink:type="arc" />
    <link:label id="lab_us-gaap_TangibleAssetImpairmentCharges_795F2E857951BA0D954DE244A9C6B44E_terseLabel_en-US" xlink:label="lab_us-gaap_TangibleAssetImpairmentCharges_795F2E857951BA0D954DE244A9C6B44E" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Asset impairment charges</link:label>
    <link:label id="lab_us-gaap_TangibleAssetImpairmentCharges_795F2E857951BA0D954DE244A9C6B44E_label_en-US" xlink:label="lab_us-gaap_TangibleAssetImpairmentCharges_795F2E857951BA0D954DE244A9C6B44E" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Tangible Asset Impairment Charges</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_TangibleAssetImpairmentCharges" xlink:label="loc_us-gaap_TangibleAssetImpairmentCharges_795F2E857951BA0D954DE244A9C6B44E" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_TangibleAssetImpairmentCharges_795F2E857951BA0D954DE244A9C6B44E" xlink:to="lab_us-gaap_TangibleAssetImpairmentCharges_795F2E857951BA0D954DE244A9C6B44E" xlink:type="arc" />
    <link:label id="lab_arnc_UndiscountedCashFlowsEffectOfOnePercentagePointDecreaseOnNetCashFlows_B5EA6AE73B79AB2F21DEE244A9C6AA55_terseLabel_en-US" xlink:label="lab_arnc_UndiscountedCashFlowsEffectOfOnePercentagePointDecreaseOnNetCashFlows_B5EA6AE73B79AB2F21DEE244A9C6AA55" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Effect of one percentage point decrease on undiscounted cash flows</link:label>
    <link:label id="lab_arnc_UndiscountedCashFlowsEffectOfOnePercentagePointDecreaseOnNetCashFlows_B5EA6AE73B79AB2F21DEE244A9C6AA55_label_en-US" xlink:label="lab_arnc_UndiscountedCashFlowsEffectOfOnePercentagePointDecreaseOnNetCashFlows_B5EA6AE73B79AB2F21DEE244A9C6AA55" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Undiscounted Cash Flows, Effect Of One Percentage Point Decrease On Net Cash Flows</link:label>
    <link:label id="lab_arnc_UndiscountedCashFlowsEffectOfOnePercentagePointDecreaseOnNetCashFlows_B5EA6AE73B79AB2F21DEE244A9C6AA55_documentation_en-US" xlink:label="lab_arnc_UndiscountedCashFlowsEffectOfOnePercentagePointDecreaseOnNetCashFlows_B5EA6AE73B79AB2F21DEE244A9C6AA55" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Undiscounted Cash Flows, Effect Of One Percentage Point Decrease On Net Cash Flows</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_UndiscountedCashFlowsEffectOfOnePercentagePointDecreaseOnNetCashFlows" xlink:label="loc_arnc_UndiscountedCashFlowsEffectOfOnePercentagePointDecreaseOnNetCashFlows_B5EA6AE73B79AB2F21DEE244A9C6AA55" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_UndiscountedCashFlowsEffectOfOnePercentagePointDecreaseOnNetCashFlows_B5EA6AE73B79AB2F21DEE244A9C6AA55" xlink:to="lab_arnc_UndiscountedCashFlowsEffectOfOnePercentagePointDecreaseOnNetCashFlows_B5EA6AE73B79AB2F21DEE244A9C6AA55" xlink:type="arc" />
    <link:label id="lab_us-gaap_PropertyPlantAndEquipmentNet_95E68127139DBFA9ED7B7C362FF1D032_verboseLabel_en-US" xlink:label="lab_us-gaap_PropertyPlantAndEquipmentNet_95E68127139DBFA9ED7B7C362FF1D032" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Long-lived assets</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PropertyPlantAndEquipmentNet" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentNet_95E68127139DBFA9ED7B7C362FF1D032" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentNet_95E68127139DBFA9ED7B7C362FF1D032" xlink:to="lab_us-gaap_PropertyPlantAndEquipmentNet_95E68127139DBFA9ED7B7C362FF1D032" xlink:type="arc" />
    <link:label id="lab_us-gaap_InventoryDisclosureAbstract_65E00D1E5F805EB6336EBE4DB8177D31_label_en-US" xlink:label="lab_us-gaap_InventoryDisclosureAbstract_65E00D1E5F805EB6336EBE4DB8177D31" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Inventory Disclosure [Abstract]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_InventoryDisclosureAbstract" xlink:label="loc_us-gaap_InventoryDisclosureAbstract_65E00D1E5F805EB6336EBE4DB8177D31" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_InventoryDisclosureAbstract_65E00D1E5F805EB6336EBE4DB8177D31" xlink:to="lab_us-gaap_InventoryDisclosureAbstract_65E00D1E5F805EB6336EBE4DB8177D31" xlink:type="arc" />
    <link:label id="lab_us-gaap_InventoryFinishedGoodsNetOfReserves_1215FACCAE3E909EF6ACBE4DB8172F92_terseLabel_en-US" xlink:label="lab_us-gaap_InventoryFinishedGoodsNetOfReserves_1215FACCAE3E909EF6ACBE4DB8172F92" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Finished goods</link:label>
    <link:label id="lab_us-gaap_InventoryFinishedGoodsNetOfReserves_1215FACCAE3E909EF6ACBE4DB8172F92_label_en-US" xlink:label="lab_us-gaap_InventoryFinishedGoodsNetOfReserves_1215FACCAE3E909EF6ACBE4DB8172F92" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Inventory, Finished Goods, Net of Reserves</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_InventoryFinishedGoodsNetOfReserves" xlink:label="loc_us-gaap_InventoryFinishedGoodsNetOfReserves_1215FACCAE3E909EF6ACBE4DB8172F92" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_InventoryFinishedGoodsNetOfReserves_1215FACCAE3E909EF6ACBE4DB8172F92" xlink:to="lab_us-gaap_InventoryFinishedGoodsNetOfReserves_1215FACCAE3E909EF6ACBE4DB8172F92" xlink:type="arc" />
    <link:label id="lab_us-gaap_InventoryWorkInProcessNetOfReserves_899DDD7DA2C3C5084AB0BE4DB818FBBF_terseLabel_en-US" xlink:label="lab_us-gaap_InventoryWorkInProcessNetOfReserves_899DDD7DA2C3C5084AB0BE4DB818FBBF" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Work-in-process</link:label>
    <link:label id="lab_us-gaap_InventoryWorkInProcessNetOfReserves_899DDD7DA2C3C5084AB0BE4DB818FBBF_label_en-US" xlink:label="lab_us-gaap_InventoryWorkInProcessNetOfReserves_899DDD7DA2C3C5084AB0BE4DB818FBBF" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Inventory, Work in Process, Net of Reserves</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_InventoryWorkInProcessNetOfReserves" xlink:label="loc_us-gaap_InventoryWorkInProcessNetOfReserves_899DDD7DA2C3C5084AB0BE4DB818FBBF" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_InventoryWorkInProcessNetOfReserves_899DDD7DA2C3C5084AB0BE4DB818FBBF" xlink:to="lab_us-gaap_InventoryWorkInProcessNetOfReserves_899DDD7DA2C3C5084AB0BE4DB818FBBF" xlink:type="arc" />
    <link:label id="lab_us-gaap_InventoryRawMaterialsNetOfReserves_988F62B3400FE38FA7EEBE4DB818BBD1_terseLabel_en-US" xlink:label="lab_us-gaap_InventoryRawMaterialsNetOfReserves_988F62B3400FE38FA7EEBE4DB818BBD1" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Purchased raw materials</link:label>
    <link:label id="lab_us-gaap_InventoryRawMaterialsNetOfReserves_988F62B3400FE38FA7EEBE4DB818BBD1_label_en-US" xlink:label="lab_us-gaap_InventoryRawMaterialsNetOfReserves_988F62B3400FE38FA7EEBE4DB818BBD1" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Inventory, Raw Materials, Net of Reserves</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_InventoryRawMaterialsNetOfReserves" xlink:label="loc_us-gaap_InventoryRawMaterialsNetOfReserves_988F62B3400FE38FA7EEBE4DB818BBD1" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_InventoryRawMaterialsNetOfReserves_988F62B3400FE38FA7EEBE4DB818BBD1" xlink:to="lab_us-gaap_InventoryRawMaterialsNetOfReserves_988F62B3400FE38FA7EEBE4DB818BBD1" xlink:type="arc" />
    <link:label id="lab_us-gaap_InventorySuppliesNetOfReserves_DA6657D0684D3D1D475DBE4DB818D25E_terseLabel_en-US" xlink:label="lab_us-gaap_InventorySuppliesNetOfReserves_DA6657D0684D3D1D475DBE4DB818D25E" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Operating supplies</link:label>
    <link:label id="lab_us-gaap_InventorySuppliesNetOfReserves_DA6657D0684D3D1D475DBE4DB818D25E_label_en-US" xlink:label="lab_us-gaap_InventorySuppliesNetOfReserves_DA6657D0684D3D1D475DBE4DB818D25E" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Inventory, Supplies, Net of Reserves</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_InventorySuppliesNetOfReserves" xlink:label="loc_us-gaap_InventorySuppliesNetOfReserves_DA6657D0684D3D1D475DBE4DB818D25E" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_InventorySuppliesNetOfReserves_DA6657D0684D3D1D475DBE4DB818D25E" xlink:to="lab_us-gaap_InventorySuppliesNetOfReserves_DA6657D0684D3D1D475DBE4DB818D25E" xlink:type="arc" />
    <link:label id="lab_us-gaap_InventoryNet_61F25F41CD22A7A1DE79BE4DB818A247_totalLabel_en-US" xlink:label="lab_us-gaap_InventoryNet_61F25F41CD22A7A1DE79BE4DB818A247" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Total inventories</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_InventoryNet" xlink:label="loc_us-gaap_InventoryNet_61F25F41CD22A7A1DE79BE4DB818A247" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_InventoryNet_61F25F41CD22A7A1DE79BE4DB818A247" xlink:to="lab_us-gaap_InventoryNet_61F25F41CD22A7A1DE79BE4DB818A247" xlink:type="arc" />
    <link:label id="lab_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosureAbstract_3D6E9BD6F0E792A3B916E244A95ADB59_label_en-US" xlink:label="lab_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosureAbstract_3D6E9BD6F0E792A3B916E244A95ADB59" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Derivative Instruments and Hedging Activities Disclosure [Abstract]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosureAbstract" xlink:label="loc_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosureAbstract_3D6E9BD6F0E792A3B916E244A95ADB59" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosureAbstract_3D6E9BD6F0E792A3B916E244A95ADB59" xlink:to="lab_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosureAbstract_3D6E9BD6F0E792A3B916E244A95ADB59" xlink:type="arc" />
    <link:label id="lab_arnc_ScheduleOfCarryingValuesAndFairValuesOfOtherFinancialInstrumentsTableTextBlock_BC020FF9C75E772AABD0E244A95A55D4_terseLabel_en-US" xlink:label="lab_arnc_ScheduleOfCarryingValuesAndFairValuesOfOtherFinancialInstrumentsTableTextBlock_BC020FF9C75E772AABD0E244A95A55D4" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Schedule of Carrying Values and Fair Values of Other Financial Instruments</link:label>
    <link:label id="lab_arnc_ScheduleOfCarryingValuesAndFairValuesOfOtherFinancialInstrumentsTableTextBlock_BC020FF9C75E772AABD0E244A95A55D4_label_en-US" xlink:label="lab_arnc_ScheduleOfCarryingValuesAndFairValuesOfOtherFinancialInstrumentsTableTextBlock_BC020FF9C75E772AABD0E244A95A55D4" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Schedule Of Carrying Values And Fair Values Of Other Financial Instruments [Table Text Block]</link:label>
    <link:label id="lab_arnc_ScheduleOfCarryingValuesAndFairValuesOfOtherFinancialInstrumentsTableTextBlock_BC020FF9C75E772AABD0E244A95A55D4_documentation_en-US" xlink:label="lab_arnc_ScheduleOfCarryingValuesAndFairValuesOfOtherFinancialInstrumentsTableTextBlock_BC020FF9C75E772AABD0E244A95A55D4" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Schedule of carrying values and fair values of other financial instruments.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_ScheduleOfCarryingValuesAndFairValuesOfOtherFinancialInstrumentsTableTextBlock" xlink:label="loc_arnc_ScheduleOfCarryingValuesAndFairValuesOfOtherFinancialInstrumentsTableTextBlock_BC020FF9C75E772AABD0E244A95A55D4" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_ScheduleOfCarryingValuesAndFairValuesOfOtherFinancialInstrumentsTableTextBlock_BC020FF9C75E772AABD0E244A95A55D4" xlink:to="lab_arnc_ScheduleOfCarryingValuesAndFairValuesOfOtherFinancialInstrumentsTableTextBlock_BC020FF9C75E772AABD0E244A95A55D4" xlink:type="arc" />
    <link:label id="lab_arnc_ScheduleOfAssetsBySegmentTable_4367ED43A51B506AF70F9F5721BFFAF6_terseLabel_en-US" xlink:label="lab_arnc_ScheduleOfAssetsBySegmentTable_4367ED43A51B506AF70F9F5721BFFAF6" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Schedule Of Assets By Segment [Table]</link:label>
    <link:label id="lab_arnc_ScheduleOfAssetsBySegmentTable_4367ED43A51B506AF70F9F5721BFFAF6_label_en-US" xlink:label="lab_arnc_ScheduleOfAssetsBySegmentTable_4367ED43A51B506AF70F9F5721BFFAF6" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Schedule Of Assets By Segment [Table]</link:label>
    <link:label id="lab_arnc_ScheduleOfAssetsBySegmentTable_4367ED43A51B506AF70F9F5721BFFAF6_documentation_en-US" xlink:label="lab_arnc_ScheduleOfAssetsBySegmentTable_4367ED43A51B506AF70F9F5721BFFAF6" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Schedule Of Assets By Segment [Table]</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_ScheduleOfAssetsBySegmentTable" xlink:label="loc_arnc_ScheduleOfAssetsBySegmentTable_4367ED43A51B506AF70F9F5721BFFAF6" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_ScheduleOfAssetsBySegmentTable_4367ED43A51B506AF70F9F5721BFFAF6" xlink:to="lab_arnc_ScheduleOfAssetsBySegmentTable_4367ED43A51B506AF70F9F5721BFFAF6" xlink:type="arc" />
    <link:label id="lab_arnc_ScheduleOfAssetsBySegmentLineItems_58696A05B4AB2B9A859F9F5721BFB2F8_terseLabel_en-US" xlink:label="lab_arnc_ScheduleOfAssetsBySegmentLineItems_58696A05B4AB2B9A859F9F5721BFB2F8" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Assets:</link:label>
    <link:label id="lab_arnc_ScheduleOfAssetsBySegmentLineItems_58696A05B4AB2B9A859F9F5721BFB2F8_label_en-US" xlink:label="lab_arnc_ScheduleOfAssetsBySegmentLineItems_58696A05B4AB2B9A859F9F5721BFB2F8" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Schedule Of Assets By Segment [Line Items]</link:label>
    <link:label id="lab_arnc_ScheduleOfAssetsBySegmentLineItems_58696A05B4AB2B9A859F9F5721BFB2F8_documentation_en-US" xlink:label="lab_arnc_ScheduleOfAssetsBySegmentLineItems_58696A05B4AB2B9A859F9F5721BFB2F8" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Schedule Of Assets By Segment [Line Items]</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_ScheduleOfAssetsBySegmentLineItems" xlink:label="loc_arnc_ScheduleOfAssetsBySegmentLineItems_58696A05B4AB2B9A859F9F5721BFB2F8" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_ScheduleOfAssetsBySegmentLineItems_58696A05B4AB2B9A859F9F5721BFB2F8" xlink:to="lab_arnc_ScheduleOfAssetsBySegmentLineItems_58696A05B4AB2B9A859F9F5721BFB2F8" xlink:type="arc" />
    <link:label id="lab_us-gaap_Assets_A5741CD6115EB98A12BF9F5721BFE068_verboseLabel_en-US" xlink:label="lab_us-gaap_Assets_A5741CD6115EB98A12BF9F5721BFE068" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Total segment assets</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_Assets" xlink:label="loc_us-gaap_Assets_A5741CD6115EB98A12BF9F5721BFE068" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_Assets_A5741CD6115EB98A12BF9F5721BFE068" xlink:to="lab_us-gaap_Assets_A5741CD6115EB98A12BF9F5721BFE068" xlink:type="arc" />
    <link:label id="lab_us-gaap_CashAndCashEquivalentsAtCarryingValue_B56E6AA815E0CB8864A59F5721BF5F71_terseLabel_en-US" xlink:label="lab_us-gaap_CashAndCashEquivalentsAtCarryingValue_B56E6AA815E0CB8864A59F5721BF5F71" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Cash and cash equivalents</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_CashAndCashEquivalentsAtCarryingValue" xlink:label="loc_us-gaap_CashAndCashEquivalentsAtCarryingValue_B56E6AA815E0CB8864A59F5721BF5F71" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CashAndCashEquivalentsAtCarryingValue_B56E6AA815E0CB8864A59F5721BF5F71" xlink:to="lab_us-gaap_CashAndCashEquivalentsAtCarryingValue_B56E6AA815E0CB8864A59F5721BF5F71" xlink:type="arc" />
    <link:label id="lab_us-gaap_DeferredTaxAssetsLiabilitiesNet_6C2A4C93CCA51D51DE409F5721BFFC0B_terseLabel_en-US" xlink:label="lab_us-gaap_DeferredTaxAssetsLiabilitiesNet_6C2A4C93CCA51D51DE409F5721BFFC0B" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Deferred income taxes</link:label>
    <link:label id="lab_us-gaap_DeferredTaxAssetsLiabilitiesNet_6C2A4C93CCA51D51DE409F5721BFFC0B_label_en-US" xlink:label="lab_us-gaap_DeferredTaxAssetsLiabilitiesNet_6C2A4C93CCA51D51DE409F5721BFFC0B" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Deferred Tax Assets, Net</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DeferredTaxAssetsLiabilitiesNet" xlink:label="loc_us-gaap_DeferredTaxAssetsLiabilitiesNet_6C2A4C93CCA51D51DE409F5721BFFC0B" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DeferredTaxAssetsLiabilitiesNet_6C2A4C93CCA51D51DE409F5721BFFC0B" xlink:to="lab_us-gaap_DeferredTaxAssetsLiabilitiesNet_6C2A4C93CCA51D51DE409F5721BFFC0B" xlink:type="arc" />
    <link:label id="lab_us-gaap_PropertyPlantAndEquipmentNet_01C1A65653F9470E38849F5721BF629B_terseLabel_en-US" xlink:label="lab_us-gaap_PropertyPlantAndEquipmentNet_01C1A65653F9470E38849F5721BF629B" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Corporate fixed assets, net</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PropertyPlantAndEquipmentNet" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentNet_01C1A65653F9470E38849F5721BF629B" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentNet_01C1A65653F9470E38849F5721BF629B" xlink:to="lab_us-gaap_PropertyPlantAndEquipmentNet_01C1A65653F9470E38849F5721BF629B" xlink:type="arc" />
    <link:label id="lab_us-gaap_DerivativeAssets_03735FE486DA3024AE649F5721BF2E20_terseLabel_en-US" xlink:label="lab_us-gaap_DerivativeAssets_03735FE486DA3024AE649F5721BF2E20" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Fair value of derivative contracts</link:label>
    <link:label id="lab_us-gaap_DerivativeAssets_03735FE486DA3024AE649F5721BF2E20_label_en-US" xlink:label="lab_us-gaap_DerivativeAssets_03735FE486DA3024AE649F5721BF2E20" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Derivative Asset</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DerivativeAssets" xlink:label="loc_us-gaap_DerivativeAssets_03735FE486DA3024AE649F5721BF2E20" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DerivativeAssets_03735FE486DA3024AE649F5721BF2E20" xlink:to="lab_us-gaap_DerivativeAssets_03735FE486DA3024AE649F5721BF2E20" xlink:type="arc" />
    <link:label id="lab_us-gaap_OtherAssets_E0217CC09A7EA6EA68AD9F5721BF9115_terseLabel_en-US" xlink:label="lab_us-gaap_OtherAssets_E0217CC09A7EA6EA68AD9F5721BF9115" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Other</link:label>
    <link:label id="lab_us-gaap_OtherAssets_E0217CC09A7EA6EA68AD9F5721BF9115_label_en-US" xlink:label="lab_us-gaap_OtherAssets_E0217CC09A7EA6EA68AD9F5721BF9115" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Other Assets</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_OtherAssets" xlink:label="loc_us-gaap_OtherAssets_E0217CC09A7EA6EA68AD9F5721BF9115" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OtherAssets_E0217CC09A7EA6EA68AD9F5721BF9115" xlink:to="lab_us-gaap_OtherAssets_E0217CC09A7EA6EA68AD9F5721BF9115" xlink:type="arc" />
    <link:label id="lab_us-gaap_UnrecognizedTaxBenefits_E75D8A133038A6F894DAF19FAD94D9A7_periodStartLabel_en-US" xlink:label="lab_us-gaap_UnrecognizedTaxBenefits_E75D8A133038A6F894DAF19FAD94D9A7" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel" xlink:type="resource" xml:lang="en-US">Balance at beginning of year</link:label>
    <link:label id="lab_us-gaap_UnrecognizedTaxBenefits_E75D8A133038A6F894DAF19FAD94D9A7_label_en-US" xlink:label="lab_us-gaap_UnrecognizedTaxBenefits_E75D8A133038A6F894DAF19FAD94D9A7" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Unrecognized Tax Benefits</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_UnrecognizedTaxBenefits" xlink:label="loc_us-gaap_UnrecognizedTaxBenefits_E75D8A133038A6F894DAF19FAD94D9A7" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_UnrecognizedTaxBenefits_E75D8A133038A6F894DAF19FAD94D9A7" xlink:to="lab_us-gaap_UnrecognizedTaxBenefits_E75D8A133038A6F894DAF19FAD94D9A7" xlink:type="arc" />
    <link:label id="lab_us-gaap_UnrecognizedTaxBenefitsIncreasesResultingFromCurrentPeriodTaxPositions_E48617C742566B101B8EF19FAD940B4D_terseLabel_en-US" xlink:label="lab_us-gaap_UnrecognizedTaxBenefitsIncreasesResultingFromCurrentPeriodTaxPositions_E48617C742566B101B8EF19FAD940B4D" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Additions for tax positions of the current year</link:label>
    <link:label id="lab_us-gaap_UnrecognizedTaxBenefitsIncreasesResultingFromCurrentPeriodTaxPositions_E48617C742566B101B8EF19FAD940B4D_label_en-US" xlink:label="lab_us-gaap_UnrecognizedTaxBenefitsIncreasesResultingFromCurrentPeriodTaxPositions_E48617C742566B101B8EF19FAD940B4D" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Unrecognized Tax Benefits, Increase Resulting from Current Period Tax Positions</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_UnrecognizedTaxBenefitsIncreasesResultingFromCurrentPeriodTaxPositions" xlink:label="loc_us-gaap_UnrecognizedTaxBenefitsIncreasesResultingFromCurrentPeriodTaxPositions_E48617C742566B101B8EF19FAD940B4D" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_UnrecognizedTaxBenefitsIncreasesResultingFromCurrentPeriodTaxPositions_E48617C742566B101B8EF19FAD940B4D" xlink:to="lab_us-gaap_UnrecognizedTaxBenefitsIncreasesResultingFromCurrentPeriodTaxPositions_E48617C742566B101B8EF19FAD940B4D" xlink:type="arc" />
    <link:label id="lab_us-gaap_UnrecognizedTaxBenefitsIncreasesResultingFromPriorPeriodTaxPositions_ED88F178F58BBEB738D9F19FAD94AE0A_terseLabel_en-US" xlink:label="lab_us-gaap_UnrecognizedTaxBenefitsIncreasesResultingFromPriorPeriodTaxPositions_ED88F178F58BBEB738D9F19FAD94AE0A" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Additions for tax positions of prior years</link:label>
    <link:label id="lab_us-gaap_UnrecognizedTaxBenefitsIncreasesResultingFromPriorPeriodTaxPositions_ED88F178F58BBEB738D9F19FAD94AE0A_label_en-US" xlink:label="lab_us-gaap_UnrecognizedTaxBenefitsIncreasesResultingFromPriorPeriodTaxPositions_ED88F178F58BBEB738D9F19FAD94AE0A" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Unrecognized Tax Benefits, Increase Resulting from Prior Period Tax Positions</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_UnrecognizedTaxBenefitsIncreasesResultingFromPriorPeriodTaxPositions" xlink:label="loc_us-gaap_UnrecognizedTaxBenefitsIncreasesResultingFromPriorPeriodTaxPositions_ED88F178F58BBEB738D9F19FAD94AE0A" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_UnrecognizedTaxBenefitsIncreasesResultingFromPriorPeriodTaxPositions_ED88F178F58BBEB738D9F19FAD94AE0A" xlink:to="lab_us-gaap_UnrecognizedTaxBenefitsIncreasesResultingFromPriorPeriodTaxPositions_ED88F178F58BBEB738D9F19FAD94AE0A" xlink:type="arc" />
    <link:label id="lab_us-gaap_UnrecognizedTaxBenefitsDecreasesResultingFromPriorPeriodTaxPositions_BBEF8D9376968E65CF80F19FAD94108B_negatedLabel_en-US" xlink:label="lab_us-gaap_UnrecognizedTaxBenefitsDecreasesResultingFromPriorPeriodTaxPositions_BBEF8D9376968E65CF80F19FAD94108B" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xml:lang="en-US">Reductions for tax positions of prior years</link:label>
    <link:label id="lab_us-gaap_UnrecognizedTaxBenefitsDecreasesResultingFromPriorPeriodTaxPositions_BBEF8D9376968E65CF80F19FAD94108B_label_en-US" xlink:label="lab_us-gaap_UnrecognizedTaxBenefitsDecreasesResultingFromPriorPeriodTaxPositions_BBEF8D9376968E65CF80F19FAD94108B" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Unrecognized Tax Benefits, Decrease Resulting from Prior Period Tax Positions</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_UnrecognizedTaxBenefitsDecreasesResultingFromPriorPeriodTaxPositions" xlink:label="loc_us-gaap_UnrecognizedTaxBenefitsDecreasesResultingFromPriorPeriodTaxPositions_BBEF8D9376968E65CF80F19FAD94108B" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_UnrecognizedTaxBenefitsDecreasesResultingFromPriorPeriodTaxPositions_BBEF8D9376968E65CF80F19FAD94108B" xlink:to="lab_us-gaap_UnrecognizedTaxBenefitsDecreasesResultingFromPriorPeriodTaxPositions_BBEF8D9376968E65CF80F19FAD94108B" xlink:type="arc" />
    <link:label id="lab_us-gaap_UnrecognizedTaxBenefitsIncreasesResultingFromSettlementsWithTaxingAuthorities_48B6CA5A8441DB89C575F19FAD940D30_negatedLabel_en-US" xlink:label="lab_us-gaap_UnrecognizedTaxBenefitsIncreasesResultingFromSettlementsWithTaxingAuthorities_48B6CA5A8441DB89C575F19FAD940D30" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xml:lang="en-US">Settlements with tax authorities</link:label>
    <link:label id="lab_us-gaap_UnrecognizedTaxBenefitsIncreasesResultingFromSettlementsWithTaxingAuthorities_48B6CA5A8441DB89C575F19FAD940D30_label_en-US" xlink:label="lab_us-gaap_UnrecognizedTaxBenefitsIncreasesResultingFromSettlementsWithTaxingAuthorities_48B6CA5A8441DB89C575F19FAD940D30" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Unrecognized Tax Benefits, Increase Resulting from Settlements with Taxing Authorities</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_UnrecognizedTaxBenefitsIncreasesResultingFromSettlementsWithTaxingAuthorities" xlink:label="loc_us-gaap_UnrecognizedTaxBenefitsIncreasesResultingFromSettlementsWithTaxingAuthorities_48B6CA5A8441DB89C575F19FAD940D30" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_UnrecognizedTaxBenefitsIncreasesResultingFromSettlementsWithTaxingAuthorities_48B6CA5A8441DB89C575F19FAD940D30" xlink:to="lab_us-gaap_UnrecognizedTaxBenefitsIncreasesResultingFromSettlementsWithTaxingAuthorities_48B6CA5A8441DB89C575F19FAD940D30" xlink:type="arc" />
    <link:label id="lab_us-gaap_UnrecognizedTaxBenefitsReductionsResultingFromLapseOfApplicableStatuteOfLimitations_8E1A3B934EE6F4AADA25F19FAD958455_negatedLabel_en-US" xlink:label="lab_us-gaap_UnrecognizedTaxBenefitsReductionsResultingFromLapseOfApplicableStatuteOfLimitations_8E1A3B934EE6F4AADA25F19FAD958455" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xml:lang="en-US">Expiration of the statute of limitations</link:label>
    <link:label id="lab_us-gaap_UnrecognizedTaxBenefitsReductionsResultingFromLapseOfApplicableStatuteOfLimitations_8E1A3B934EE6F4AADA25F19FAD958455_label_en-US" xlink:label="lab_us-gaap_UnrecognizedTaxBenefitsReductionsResultingFromLapseOfApplicableStatuteOfLimitations_8E1A3B934EE6F4AADA25F19FAD958455" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Unrecognized Tax Benefits, Reduction Resulting from Lapse of Applicable Statute of Limitations</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_UnrecognizedTaxBenefitsReductionsResultingFromLapseOfApplicableStatuteOfLimitations" xlink:label="loc_us-gaap_UnrecognizedTaxBenefitsReductionsResultingFromLapseOfApplicableStatuteOfLimitations_8E1A3B934EE6F4AADA25F19FAD958455" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_UnrecognizedTaxBenefitsReductionsResultingFromLapseOfApplicableStatuteOfLimitations_8E1A3B934EE6F4AADA25F19FAD958455" xlink:to="lab_us-gaap_UnrecognizedTaxBenefitsReductionsResultingFromLapseOfApplicableStatuteOfLimitations_8E1A3B934EE6F4AADA25F19FAD958455" xlink:type="arc" />
    <link:label id="lab_arnc_UnrecognizedTaxBenefitsForeignCurrencyTranslation_A99F0CDB934B5274E24EF19FAD956320_negatedTerseLabel_en-US" xlink:label="lab_arnc_UnrecognizedTaxBenefitsForeignCurrencyTranslation_A99F0CDB934B5274E24EF19FAD956320" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:type="resource" xml:lang="en-US">Foreign currency translation</link:label>
    <link:label id="lab_arnc_UnrecognizedTaxBenefitsForeignCurrencyTranslation_A99F0CDB934B5274E24EF19FAD956320_label_en-US" xlink:label="lab_arnc_UnrecognizedTaxBenefitsForeignCurrencyTranslation_A99F0CDB934B5274E24EF19FAD956320" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Unrecognized Tax Benefits Foreign Currency Translation</link:label>
    <link:label id="lab_arnc_UnrecognizedTaxBenefitsForeignCurrencyTranslation_A99F0CDB934B5274E24EF19FAD956320_documentation_en-US" xlink:label="lab_arnc_UnrecognizedTaxBenefitsForeignCurrencyTranslation_A99F0CDB934B5274E24EF19FAD956320" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Unrecognized tax benefits foreign currency translation.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_UnrecognizedTaxBenefitsForeignCurrencyTranslation" xlink:label="loc_arnc_UnrecognizedTaxBenefitsForeignCurrencyTranslation_A99F0CDB934B5274E24EF19FAD956320" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_UnrecognizedTaxBenefitsForeignCurrencyTranslation_A99F0CDB934B5274E24EF19FAD956320" xlink:to="lab_arnc_UnrecognizedTaxBenefitsForeignCurrencyTranslation_A99F0CDB934B5274E24EF19FAD956320" xlink:type="arc" />
    <link:label id="lab_us-gaap_UnrecognizedTaxBenefits_CD4847EB47E7AED7A9A3F19FAD95C234_periodEndLabel_en-US" xlink:label="lab_us-gaap_UnrecognizedTaxBenefits_CD4847EB47E7AED7A9A3F19FAD95C234" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel" xlink:type="resource" xml:lang="en-US">Balance at end of year</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_UnrecognizedTaxBenefits" xlink:label="loc_us-gaap_UnrecognizedTaxBenefits_CD4847EB47E7AED7A9A3F19FAD95C234" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_UnrecognizedTaxBenefits_CD4847EB47E7AED7A9A3F19FAD95C234" xlink:to="lab_us-gaap_UnrecognizedTaxBenefits_CD4847EB47E7AED7A9A3F19FAD95C234" xlink:type="arc" />
    <link:label id="lab_us-gaap_DefinedBenefitPlanWeightedAverageAssumptionsUsedInCalculatingBenefitObligationAbstract_50914CE4F2278EE00DEDDEFAB9BF807F_terseLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanWeightedAverageAssumptionsUsedInCalculatingBenefitObligationAbstract_50914CE4F2278EE00DEDDEFAB9BF807F" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Benefit Obligation [Abstract]</link:label>
    <link:label id="lab_us-gaap_DefinedBenefitPlanWeightedAverageAssumptionsUsedInCalculatingBenefitObligationAbstract_50914CE4F2278EE00DEDDEFAB9BF807F_label_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanWeightedAverageAssumptionsUsedInCalculatingBenefitObligationAbstract_50914CE4F2278EE00DEDDEFAB9BF807F" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Benefit Obligation [Abstract]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DefinedBenefitPlanWeightedAverageAssumptionsUsedInCalculatingBenefitObligationAbstract" xlink:label="loc_us-gaap_DefinedBenefitPlanWeightedAverageAssumptionsUsedInCalculatingBenefitObligationAbstract_50914CE4F2278EE00DEDDEFAB9BF807F" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanWeightedAverageAssumptionsUsedInCalculatingBenefitObligationAbstract_50914CE4F2278EE00DEDDEFAB9BF807F" xlink:to="lab_us-gaap_DefinedBenefitPlanWeightedAverageAssumptionsUsedInCalculatingBenefitObligationAbstract_50914CE4F2278EE00DEDDEFAB9BF807F" xlink:type="arc" />
    <link:label id="lab_us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationDiscountRate_F71E30E236E29458B1E6DEFAB9BFBD6A_terseLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationDiscountRate_F71E30E236E29458B1E6DEFAB9BFBD6A" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Discount rate</link:label>
    <link:label id="lab_us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationDiscountRate_F71E30E236E29458B1E6DEFAB9BFBD6A_label_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationDiscountRate_F71E30E236E29458B1E6DEFAB9BFBD6A" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Discount Rate</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationDiscountRate" xlink:label="loc_us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationDiscountRate_F71E30E236E29458B1E6DEFAB9BFBD6A" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationDiscountRate_F71E30E236E29458B1E6DEFAB9BFBD6A" xlink:to="lab_us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationDiscountRate_F71E30E236E29458B1E6DEFAB9BFBD6A" xlink:type="arc" />
    <link:label id="lab_us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationRateOfCompensationIncrease_94F29AE485BB25B39BFCDEFAB9BFBAF8_verboseLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationRateOfCompensationIncrease_94F29AE485BB25B39BFCDEFAB9BFBAF8" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Rate of compensation increase</link:label>
    <link:label id="lab_us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationRateOfCompensationIncrease_94F29AE485BB25B39BFCDEFAB9BFBAF8_label_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationRateOfCompensationIncrease_94F29AE485BB25B39BFCDEFAB9BFBAF8" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Rate of Compensation Increase</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationRateOfCompensationIncrease" xlink:label="loc_us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationRateOfCompensationIncrease_94F29AE485BB25B39BFCDEFAB9BFBAF8" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationRateOfCompensationIncrease_94F29AE485BB25B39BFCDEFAB9BFBAF8" xlink:to="lab_us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationRateOfCompensationIncrease_94F29AE485BB25B39BFCDEFAB9BFBAF8" xlink:type="arc" />
    <link:label id="lab_us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostChangeDueToSubsequentInterimMeasurementWeightedAverageExpectedLongTermRateOfReturnOnPlanAssets_D467001819EE7F5D3B7BDF2FD8B147AD_terseLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostChangeDueToSubsequentInterimMeasurementWeightedAverageExpectedLongTermRateOfReturnOnPlanAssets_D467001819EE7F5D3B7BDF2FD8B147AD" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Cash balance plan interest crediting rate</link:label>
    <link:label id="lab_us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostChangeDueToSubsequentInterimMeasurementWeightedAverageExpectedLongTermRateOfReturnOnPlanAssets_D467001819EE7F5D3B7BDF2FD8B147AD_label_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostChangeDueToSubsequentInterimMeasurementWeightedAverageExpectedLongTermRateOfReturnOnPlanAssets_D467001819EE7F5D3B7BDF2FD8B147AD" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Change Due to Subsequent Interim Measurement, Weighted-Average Expected Long-term Rate of Return on Plan Assets</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostChangeDueToSubsequentInterimMeasurementWeightedAverageExpectedLongTermRateOfReturnOnPlanAssets" xlink:label="loc_us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostChangeDueToSubsequentInterimMeasurementWeightedAverageExpectedLongTermRateOfReturnOnPlanAssets_D467001819EE7F5D3B7BDF2FD8B147AD" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostChangeDueToSubsequentInterimMeasurementWeightedAverageExpectedLongTermRateOfReturnOnPlanAssets_D467001819EE7F5D3B7BDF2FD8B147AD" xlink:to="lab_us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostChangeDueToSubsequentInterimMeasurementWeightedAverageExpectedLongTermRateOfReturnOnPlanAssets_D467001819EE7F5D3B7BDF2FD8B147AD" xlink:type="arc" />
    <link:label id="lab_arnc_DefinedBenefitPlanFairValueAssumptionsAverageDurationRefinedYieldCurveModelParallelsPlans_B3ADB839A364A63F67F6DEFAB9BF8724_terseLabel_en-US" xlink:label="lab_arnc_DefinedBenefitPlanFairValueAssumptionsAverageDurationRefinedYieldCurveModelParallelsPlans_B3ADB839A364A63F67F6DEFAB9BF8724" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Average duration for plans' projected cash flows</link:label>
    <link:label id="lab_arnc_DefinedBenefitPlanFairValueAssumptionsAverageDurationRefinedYieldCurveModelParallelsPlans_B3ADB839A364A63F67F6DEFAB9BF8724_label_en-US" xlink:label="lab_arnc_DefinedBenefitPlanFairValueAssumptionsAverageDurationRefinedYieldCurveModelParallelsPlans_B3ADB839A364A63F67F6DEFAB9BF8724" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Fair Value Assumptions, Average Duration Refined Yield Curve Model Parallels Plans</link:label>
    <link:label id="lab_arnc_DefinedBenefitPlanFairValueAssumptionsAverageDurationRefinedYieldCurveModelParallelsPlans_B3ADB839A364A63F67F6DEFAB9BF8724_documentation_en-US" xlink:label="lab_arnc_DefinedBenefitPlanFairValueAssumptionsAverageDurationRefinedYieldCurveModelParallelsPlans_B3ADB839A364A63F67F6DEFAB9BF8724" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Average duration refined yield curve model parallels the plans.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_DefinedBenefitPlanFairValueAssumptionsAverageDurationRefinedYieldCurveModelParallelsPlans" xlink:label="loc_arnc_DefinedBenefitPlanFairValueAssumptionsAverageDurationRefinedYieldCurveModelParallelsPlans_B3ADB839A364A63F67F6DEFAB9BF8724" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_DefinedBenefitPlanFairValueAssumptionsAverageDurationRefinedYieldCurveModelParallelsPlans_B3ADB839A364A63F67F6DEFAB9BF8724" xlink:to="lab_arnc_DefinedBenefitPlanFairValueAssumptionsAverageDurationRefinedYieldCurveModelParallelsPlans_B3ADB839A364A63F67F6DEFAB9BF8724" xlink:type="arc" />
    <link:label id="lab_arnc_PeriodOfObservationToDetermineAverageCompensationIncrease_A09C036F4F25AA42AA89DEFAB9BFAFD1_terseLabel_en-US" xlink:label="lab_arnc_PeriodOfObservationToDetermineAverageCompensationIncrease_A09C036F4F25AA42AA89DEFAB9BFAFD1" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Period of observation to determine average compensation increase</link:label>
    <link:label id="lab_arnc_PeriodOfObservationToDetermineAverageCompensationIncrease_A09C036F4F25AA42AA89DEFAB9BFAFD1_label_en-US" xlink:label="lab_arnc_PeriodOfObservationToDetermineAverageCompensationIncrease_A09C036F4F25AA42AA89DEFAB9BFAFD1" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Period Of Observation To Determine Average Compensation Increase</link:label>
    <link:label id="lab_arnc_PeriodOfObservationToDetermineAverageCompensationIncrease_A09C036F4F25AA42AA89DEFAB9BFAFD1_documentation_en-US" xlink:label="lab_arnc_PeriodOfObservationToDetermineAverageCompensationIncrease_A09C036F4F25AA42AA89DEFAB9BFAFD1" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Period of observation to determine average compensation increase.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_PeriodOfObservationToDetermineAverageCompensationIncrease" xlink:label="loc_arnc_PeriodOfObservationToDetermineAverageCompensationIncrease_A09C036F4F25AA42AA89DEFAB9BFAFD1" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_PeriodOfObservationToDetermineAverageCompensationIncrease_A09C036F4F25AA42AA89DEFAB9BFAFD1" xlink:to="lab_arnc_PeriodOfObservationToDetermineAverageCompensationIncrease_A09C036F4F25AA42AA89DEFAB9BFAFD1" xlink:type="arc" />
    <link:label id="lab_us-gaap_DefinedBenefitPlanWeightedAverageAssumptionsUsedInCalculatingNetPeriodicBenefitCostAbstract_43C4A41C5797663A8A92DEFAB9BF2FBB_terseLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanWeightedAverageAssumptionsUsedInCalculatingNetPeriodicBenefitCostAbstract_43C4A41C5797663A8A92DEFAB9BF2FBB" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]</link:label>
    <link:label id="lab_us-gaap_DefinedBenefitPlanWeightedAverageAssumptionsUsedInCalculatingNetPeriodicBenefitCostAbstract_43C4A41C5797663A8A92DEFAB9BF2FBB_label_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanWeightedAverageAssumptionsUsedInCalculatingNetPeriodicBenefitCostAbstract_43C4A41C5797663A8A92DEFAB9BF2FBB" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DefinedBenefitPlanWeightedAverageAssumptionsUsedInCalculatingNetPeriodicBenefitCostAbstract" xlink:label="loc_us-gaap_DefinedBenefitPlanWeightedAverageAssumptionsUsedInCalculatingNetPeriodicBenefitCostAbstract_43C4A41C5797663A8A92DEFAB9BF2FBB" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanWeightedAverageAssumptionsUsedInCalculatingNetPeriodicBenefitCostAbstract_43C4A41C5797663A8A92DEFAB9BF2FBB" xlink:to="lab_us-gaap_DefinedBenefitPlanWeightedAverageAssumptionsUsedInCalculatingNetPeriodicBenefitCostAbstract_43C4A41C5797663A8A92DEFAB9BF2FBB" xlink:type="arc" />
    <link:label id="lab_arnc_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostServiceCostDiscountRate_FB495A7665AA94743C8EDEFAB9BF02C1_terseLabel_en-US" xlink:label="lab_arnc_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostServiceCostDiscountRate_FB495A7665AA94743C8EDEFAB9BF02C1" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Discount rate to calculate service cost</link:label>
    <link:label id="lab_arnc_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostServiceCostDiscountRate_FB495A7665AA94743C8EDEFAB9BF02C1_label_en-US" xlink:label="lab_arnc_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostServiceCostDiscountRate_FB495A7665AA94743C8EDEFAB9BF02C1" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Service Cost, Discount Rate</link:label>
    <link:label id="lab_arnc_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostServiceCostDiscountRate_FB495A7665AA94743C8EDEFAB9BF02C1_documentation_en-US" xlink:label="lab_arnc_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostServiceCostDiscountRate_FB495A7665AA94743C8EDEFAB9BF02C1" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Service Cost, Discount Rate</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostServiceCostDiscountRate" xlink:label="loc_arnc_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostServiceCostDiscountRate_FB495A7665AA94743C8EDEFAB9BF02C1" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostServiceCostDiscountRate_FB495A7665AA94743C8EDEFAB9BF02C1" xlink:to="lab_arnc_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostServiceCostDiscountRate_FB495A7665AA94743C8EDEFAB9BF02C1" xlink:type="arc" />
    <link:label id="lab_arnc_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostInterestCostDiscountRate_FEE1AF7D72DF1E04E7DFDEFAB9BF7E0E_terseLabel_en-US" xlink:label="lab_arnc_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostInterestCostDiscountRate_FEE1AF7D72DF1E04E7DFDEFAB9BF7E0E" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Discount rate to calculate interest cost</link:label>
    <link:label id="lab_arnc_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostInterestCostDiscountRate_FEE1AF7D72DF1E04E7DFDEFAB9BF7E0E_label_en-US" xlink:label="lab_arnc_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostInterestCostDiscountRate_FEE1AF7D72DF1E04E7DFDEFAB9BF7E0E" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Interest Cost, Discount Rate</link:label>
    <link:label id="lab_arnc_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostInterestCostDiscountRate_FEE1AF7D72DF1E04E7DFDEFAB9BF7E0E_documentation_en-US" xlink:label="lab_arnc_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostInterestCostDiscountRate_FEE1AF7D72DF1E04E7DFDEFAB9BF7E0E" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Interest Cost, Discount Rate</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostInterestCostDiscountRate" xlink:label="loc_arnc_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostInterestCostDiscountRate_FEE1AF7D72DF1E04E7DFDEFAB9BF7E0E" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostInterestCostDiscountRate_FEE1AF7D72DF1E04E7DFDEFAB9BF7E0E" xlink:to="lab_arnc_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostInterestCostDiscountRate_FEE1AF7D72DF1E04E7DFDEFAB9BF7E0E" xlink:type="arc" />
    <link:label id="lab_us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostExpectedLongTermReturnOnAssets_804C01730EAD99F74A3BDEFAB9BF1DCD_verboseLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostExpectedLongTermReturnOnAssets_804C01730EAD99F74A3BDEFAB9BF1DCD" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Expected long-term rate of return on plan assets</link:label>
    <link:label id="lab_us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostExpectedLongTermReturnOnAssets_804C01730EAD99F74A3BDEFAB9BF1DCD_label_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostExpectedLongTermReturnOnAssets_804C01730EAD99F74A3BDEFAB9BF1DCD" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Expected Long-term Rate of Return on Plan Assets</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostExpectedLongTermReturnOnAssets" xlink:label="loc_us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostExpectedLongTermReturnOnAssets_804C01730EAD99F74A3BDEFAB9BF1DCD" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostExpectedLongTermReturnOnAssets_804C01730EAD99F74A3BDEFAB9BF1DCD" xlink:to="lab_us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostExpectedLongTermReturnOnAssets_804C01730EAD99F74A3BDEFAB9BF1DCD" xlink:type="arc" />
    <link:label id="lab_us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostRateOfCompensationIncrease_440AE72C847E886C0A76DEFAB9BF539D_terseLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostRateOfCompensationIncrease_440AE72C847E886C0A76DEFAB9BF539D" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Rate of compensation increase</link:label>
    <link:label id="lab_us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostRateOfCompensationIncrease_440AE72C847E886C0A76DEFAB9BF539D_label_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostRateOfCompensationIncrease_440AE72C847E886C0A76DEFAB9BF539D" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Rate of Compensation Increase</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostRateOfCompensationIncrease" xlink:label="loc_us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostRateOfCompensationIncrease_440AE72C847E886C0A76DEFAB9BF539D" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostRateOfCompensationIncrease_440AE72C847E886C0A76DEFAB9BF539D" xlink:to="lab_us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostRateOfCompensationIncrease_440AE72C847E886C0A76DEFAB9BF539D" xlink:type="arc" />
    <link:label id="lab_arnc_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostCashBalancePlanInterestCreditingRate_655C561BCB70A37018C0DEFAB9BFC38F_terseLabel_en-US" xlink:label="lab_arnc_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostCashBalancePlanInterestCreditingRate_655C561BCB70A37018C0DEFAB9BFC38F" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Cash balance plan interest crediting rate</link:label>
    <link:label id="lab_arnc_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostCashBalancePlanInterestCreditingRate_655C561BCB70A37018C0DEFAB9BFC38F_label_en-US" xlink:label="lab_arnc_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostCashBalancePlanInterestCreditingRate_655C561BCB70A37018C0DEFAB9BFC38F" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Cash Balance Plan Interest Crediting Rate</link:label>
    <link:label id="lab_arnc_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostCashBalancePlanInterestCreditingRate_655C561BCB70A37018C0DEFAB9BFC38F_documentation_en-US" xlink:label="lab_arnc_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostCashBalancePlanInterestCreditingRate_655C561BCB70A37018C0DEFAB9BFC38F" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Cash Balance Plan Interest Crediting Rate</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostCashBalancePlanInterestCreditingRate" xlink:label="loc_arnc_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostCashBalancePlanInterestCreditingRate_655C561BCB70A37018C0DEFAB9BFC38F" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostCashBalancePlanInterestCreditingRate_655C561BCB70A37018C0DEFAB9BFC38F" xlink:to="lab_arnc_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostCashBalancePlanInterestCreditingRate_655C561BCB70A37018C0DEFAB9BFC38F" xlink:type="arc" />
    <link:label id="lab_arnc_DefinedBenefitPlanInterestCostChangeInAccountingEstimateImpact_2D4BB6D019CB04F15396DEFAB9BFDDB8_terseLabel_en-US" xlink:label="lab_arnc_DefinedBenefitPlanInterestCostChangeInAccountingEstimateImpact_2D4BB6D019CB04F15396DEFAB9BFDDB8" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Interest cost component related to net periodic benefit cost</link:label>
    <link:label id="lab_arnc_DefinedBenefitPlanInterestCostChangeInAccountingEstimateImpact_2D4BB6D019CB04F15396DEFAB9BFDDB8_label_en-US" xlink:label="lab_arnc_DefinedBenefitPlanInterestCostChangeInAccountingEstimateImpact_2D4BB6D019CB04F15396DEFAB9BFDDB8" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan Interest Cost Change In Accounting Estimate Impact</link:label>
    <link:label id="lab_arnc_DefinedBenefitPlanInterestCostChangeInAccountingEstimateImpact_2D4BB6D019CB04F15396DEFAB9BFDDB8_documentation_en-US" xlink:label="lab_arnc_DefinedBenefitPlanInterestCostChangeInAccountingEstimateImpact_2D4BB6D019CB04F15396DEFAB9BFDDB8" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">The estimated reduction in interest cost upon application of change in accounting estimate in next fiscal year.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_DefinedBenefitPlanInterestCostChangeInAccountingEstimateImpact" xlink:label="loc_arnc_DefinedBenefitPlanInterestCostChangeInAccountingEstimateImpact_2D4BB6D019CB04F15396DEFAB9BFDDB8" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_DefinedBenefitPlanInterestCostChangeInAccountingEstimateImpact_2D4BB6D019CB04F15396DEFAB9BFDDB8" xlink:to="lab_arnc_DefinedBenefitPlanInterestCostChangeInAccountingEstimateImpact_2D4BB6D019CB04F15396DEFAB9BFDDB8" xlink:type="arc" />
    <link:label id="lab_arnc_AveragePeriodOfHistoricalReturnsUsedToCalculateExpectedFutureReturns_ED819F004C56CD6BEAF2DEFAB9BFF34C_terseLabel_en-US" xlink:label="lab_arnc_AveragePeriodOfHistoricalReturnsUsedToCalculateExpectedFutureReturns_ED819F004C56CD6BEAF2DEFAB9BFF34C" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Period expected long-term rate of return is applied</link:label>
    <link:label id="lab_arnc_AveragePeriodOfHistoricalReturnsUsedToCalculateExpectedFutureReturns_ED819F004C56CD6BEAF2DEFAB9BFF34C_label_en-US" xlink:label="lab_arnc_AveragePeriodOfHistoricalReturnsUsedToCalculateExpectedFutureReturns_ED819F004C56CD6BEAF2DEFAB9BFF34C" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Average Period Of Historical Returns Used To Calculate Expected Future Returns</link:label>
    <link:label id="lab_arnc_AveragePeriodOfHistoricalReturnsUsedToCalculateExpectedFutureReturns_ED819F004C56CD6BEAF2DEFAB9BFF34C_documentation_en-US" xlink:label="lab_arnc_AveragePeriodOfHistoricalReturnsUsedToCalculateExpectedFutureReturns_ED819F004C56CD6BEAF2DEFAB9BFF34C" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Average period of historical returns used to calculate expected future returns, years.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_AveragePeriodOfHistoricalReturnsUsedToCalculateExpectedFutureReturns" xlink:label="loc_arnc_AveragePeriodOfHistoricalReturnsUsedToCalculateExpectedFutureReturns_ED819F004C56CD6BEAF2DEFAB9BFF34C" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_AveragePeriodOfHistoricalReturnsUsedToCalculateExpectedFutureReturns_ED819F004C56CD6BEAF2DEFAB9BFF34C" xlink:to="lab_arnc_AveragePeriodOfHistoricalReturnsUsedToCalculateExpectedFutureReturns_ED819F004C56CD6BEAF2DEFAB9BFF34C" xlink:type="arc" />
    <link:label id="lab_arnc_BasisPointOfDecreaseIdentifiedInLongTermRateOfReturn_6BD09F2506D0D2D7D8F4DEFAB9BFF4DC_terseLabel_en-US" xlink:label="lab_arnc_BasisPointOfDecreaseIdentifiedInLongTermRateOfReturn_6BD09F2506D0D2D7D8F4DEFAB9BFF4DC" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Basis point of decrease identified In long term rate of return</link:label>
    <link:label id="lab_arnc_BasisPointOfDecreaseIdentifiedInLongTermRateOfReturn_6BD09F2506D0D2D7D8F4DEFAB9BFF4DC_label_en-US" xlink:label="lab_arnc_BasisPointOfDecreaseIdentifiedInLongTermRateOfReturn_6BD09F2506D0D2D7D8F4DEFAB9BFF4DC" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Basis Point Of Decrease Identified In Long Term Rate Of Return</link:label>
    <link:label id="lab_arnc_BasisPointOfDecreaseIdentifiedInLongTermRateOfReturn_6BD09F2506D0D2D7D8F4DEFAB9BFF4DC_documentation_en-US" xlink:label="lab_arnc_BasisPointOfDecreaseIdentifiedInLongTermRateOfReturn_6BD09F2506D0D2D7D8F4DEFAB9BFF4DC" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Basis point of decrease identified in long term rate of return.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_BasisPointOfDecreaseIdentifiedInLongTermRateOfReturn" xlink:label="loc_arnc_BasisPointOfDecreaseIdentifiedInLongTermRateOfReturn_6BD09F2506D0D2D7D8F4DEFAB9BFF4DC" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_BasisPointOfDecreaseIdentifiedInLongTermRateOfReturn_6BD09F2506D0D2D7D8F4DEFAB9BFF4DC" xlink:to="lab_arnc_BasisPointOfDecreaseIdentifiedInLongTermRateOfReturn_6BD09F2506D0D2D7D8F4DEFAB9BFF4DC" xlink:type="arc" />
    <link:label id="lab_us-gaap_InventoryDisclosureTextBlock_9FAD3E68297F3117926B7C362D7283DC_terseLabel_en-US" xlink:label="lab_us-gaap_InventoryDisclosureTextBlock_9FAD3E68297F3117926B7C362D7283DC" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Inventories</link:label>
    <link:label id="lab_us-gaap_InventoryDisclosureTextBlock_9FAD3E68297F3117926B7C362D7283DC_label_en-US" xlink:label="lab_us-gaap_InventoryDisclosureTextBlock_9FAD3E68297F3117926B7C362D7283DC" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Inventory Disclosure [Text Block]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_InventoryDisclosureTextBlock" xlink:label="loc_us-gaap_InventoryDisclosureTextBlock_9FAD3E68297F3117926B7C362D7283DC" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_InventoryDisclosureTextBlock_9FAD3E68297F3117926B7C362D7283DC" xlink:to="lab_us-gaap_InventoryDisclosureTextBlock_9FAD3E68297F3117926B7C362D7283DC" xlink:type="arc" />
    <link:label id="lab_us-gaap_ScheduleOfQuarterlyFinancialInformationTableTextBlock_8AD5E7D2ED84C12C0433E244A88E9FEF_terseLabel_en-US" xlink:label="lab_us-gaap_ScheduleOfQuarterlyFinancialInformationTableTextBlock_8AD5E7D2ED84C12C0433E244A88E9FEF" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Schedule of Quarterly Data</link:label>
    <link:label id="lab_us-gaap_ScheduleOfQuarterlyFinancialInformationTableTextBlock_8AD5E7D2ED84C12C0433E244A88E9FEF_label_en-US" xlink:label="lab_us-gaap_ScheduleOfQuarterlyFinancialInformationTableTextBlock_8AD5E7D2ED84C12C0433E244A88E9FEF" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Quarterly Financial Information [Table Text Block]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ScheduleOfQuarterlyFinancialInformationTableTextBlock" xlink:label="loc_us-gaap_ScheduleOfQuarterlyFinancialInformationTableTextBlock_8AD5E7D2ED84C12C0433E244A88E9FEF" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfQuarterlyFinancialInformationTableTextBlock_8AD5E7D2ED84C12C0433E244A88E9FEF" xlink:to="lab_us-gaap_ScheduleOfQuarterlyFinancialInformationTableTextBlock_8AD5E7D2ED84C12C0433E244A88E9FEF" xlink:type="arc" />
    <link:label id="lab_arnc_RecurringCostsOfManagingHazardousSubstancesAndEnvironmentalProgramsMember_D0CFAD9EEDDE6D30E007E244A8FADF93_terseLabel_en-US" xlink:label="lab_arnc_RecurringCostsOfManagingHazardousSubstancesAndEnvironmentalProgramsMember_D0CFAD9EEDDE6D30E007E244A8FADF93" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Recurring Costs of Managing Hazardous Substances and Environmental Programs</link:label>
    <link:label id="lab_arnc_RecurringCostsOfManagingHazardousSubstancesAndEnvironmentalProgramsMember_D0CFAD9EEDDE6D30E007E244A8FADF93_label_en-US" xlink:label="lab_arnc_RecurringCostsOfManagingHazardousSubstancesAndEnvironmentalProgramsMember_D0CFAD9EEDDE6D30E007E244A8FADF93" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Recurring Costs Of Managing Hazardous Substances And Environmental Programs [Member]</link:label>
    <link:label id="lab_arnc_RecurringCostsOfManagingHazardousSubstancesAndEnvironmentalProgramsMember_D0CFAD9EEDDE6D30E007E244A8FADF93_documentation_en-US" xlink:label="lab_arnc_RecurringCostsOfManagingHazardousSubstancesAndEnvironmentalProgramsMember_D0CFAD9EEDDE6D30E007E244A8FADF93" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Recurring costs of managing hazardous substances and environmental programs.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_RecurringCostsOfManagingHazardousSubstancesAndEnvironmentalProgramsMember" xlink:label="loc_arnc_RecurringCostsOfManagingHazardousSubstancesAndEnvironmentalProgramsMember_D0CFAD9EEDDE6D30E007E244A8FADF93" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_RecurringCostsOfManagingHazardousSubstancesAndEnvironmentalProgramsMember_D0CFAD9EEDDE6D30E007E244A8FADF93" xlink:to="lab_arnc_RecurringCostsOfManagingHazardousSubstancesAndEnvironmentalProgramsMember_D0CFAD9EEDDE6D30E007E244A8FADF93" xlink:type="arc" />
    <link:label id="lab_arnc_MassenaNyMember_A276D2666BF98C41C63DE244A8FAFE67_terseLabel_en-US" xlink:label="lab_arnc_MassenaNyMember_A276D2666BF98C41C63DE244A8FAFE67" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Massena West, NY</link:label>
    <link:label id="lab_arnc_MassenaNyMember_A276D2666BF98C41C63DE244A8FAFE67_label_en-US" xlink:label="lab_arnc_MassenaNyMember_A276D2666BF98C41C63DE244A8FAFE67" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Massena NY [Member]</link:label>
    <link:label id="lab_arnc_MassenaNyMember_A276D2666BF98C41C63DE244A8FAFE67_documentation_en-US" xlink:label="lab_arnc_MassenaNyMember_A276D2666BF98C41C63DE244A8FAFE67" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Massena, NY.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_MassenaNyMember" xlink:label="loc_arnc_MassenaNyMember_A276D2666BF98C41C63DE244A8FAFE67" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_MassenaNyMember_A276D2666BF98C41C63DE244A8FAFE67" xlink:to="lab_arnc_MassenaNyMember_A276D2666BF98C41C63DE244A8FAFE67" xlink:type="arc" />
    <link:label id="lab_country_ES_73B14F773717A6CFBA5CE244A8FE514B_terseLabel_en-US" xlink:label="lab_country_ES_73B14F773717A6CFBA5CE244A8FE514B" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Spain</link:label>
    <link:label id="lab_country_ES_73B14F773717A6CFBA5CE244A8FE514B_label_en-US" xlink:label="lab_country_ES_73B14F773717A6CFBA5CE244A8FE514B" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">SPAIN</link:label>
    <link:loc xlink:href="http://xbrl.sec.gov/country/2017/country-2017-01-31.xsd#country_ES" xlink:label="loc_country_ES_73B14F773717A6CFBA5CE244A8FE514B" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_country_ES_73B14F773717A6CFBA5CE244A8FE514B" xlink:to="lab_country_ES_73B14F773717A6CFBA5CE244A8FE514B" xlink:type="arc" />
    <link:label id="lab_arnc_NumberOfCleanupLocations_2266CE1A705174A41E6DE244A8FE27EB_terseLabel_en-US" xlink:label="lab_arnc_NumberOfCleanupLocations_2266CE1A705174A41E6DE244A8FE27EB" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Number of cleanup locations (more than)</link:label>
    <link:label id="lab_arnc_NumberOfCleanupLocations_2266CE1A705174A41E6DE244A8FE27EB_label_en-US" xlink:label="lab_arnc_NumberOfCleanupLocations_2266CE1A705174A41E6DE244A8FE27EB" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Number Of Cleanup Locations</link:label>
    <link:label id="lab_arnc_NumberOfCleanupLocations_2266CE1A705174A41E6DE244A8FE27EB_documentation_en-US" xlink:label="lab_arnc_NumberOfCleanupLocations_2266CE1A705174A41E6DE244A8FE27EB" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Number of cleanup locations.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_NumberOfCleanupLocations" xlink:label="loc_arnc_NumberOfCleanupLocations_2266CE1A705174A41E6DE244A8FE27EB" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_NumberOfCleanupLocations_2266CE1A705174A41E6DE244A8FE27EB" xlink:to="lab_arnc_NumberOfCleanupLocations_2266CE1A705174A41E6DE244A8FE27EB" xlink:type="arc" />
    <link:label id="lab_us-gaap_AccrualForEnvironmentalLossContingencies_C40C0070A47B3D983348E244A8FE835A_terseLabel_en-US" xlink:label="lab_us-gaap_AccrualForEnvironmentalLossContingencies_C40C0070A47B3D983348E244A8FE835A" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Remediation reserve balance</link:label>
    <link:label id="lab_us-gaap_AccrualForEnvironmentalLossContingencies_C40C0070A47B3D983348E244A8FE835A_label_en-US" xlink:label="lab_us-gaap_AccrualForEnvironmentalLossContingencies_C40C0070A47B3D983348E244A8FE835A" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Accrual for Environmental Loss Contingencies</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AccrualForEnvironmentalLossContingencies" xlink:label="loc_us-gaap_AccrualForEnvironmentalLossContingencies_C40C0070A47B3D983348E244A8FE835A" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AccrualForEnvironmentalLossContingencies_C40C0070A47B3D983348E244A8FE835A" xlink:to="lab_us-gaap_AccrualForEnvironmentalLossContingencies_C40C0070A47B3D983348E244A8FE835A" xlink:type="arc" />
    <link:label id="lab_us-gaap_AccruedEnvironmentalLossContingenciesCurrent_84B1795DF0A3C13C9474E244A8FED8DC_terseLabel_en-US" xlink:label="lab_us-gaap_AccruedEnvironmentalLossContingenciesCurrent_84B1795DF0A3C13C9474E244A8FED8DC" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Remediation reserve balance, classified as a current liability</link:label>
    <link:label id="lab_us-gaap_AccruedEnvironmentalLossContingenciesCurrent_84B1795DF0A3C13C9474E244A8FED8DC_label_en-US" xlink:label="lab_us-gaap_AccruedEnvironmentalLossContingenciesCurrent_84B1795DF0A3C13C9474E244A8FED8DC" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Accrued Environmental Loss Contingencies, Current</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AccruedEnvironmentalLossContingenciesCurrent" xlink:label="loc_us-gaap_AccruedEnvironmentalLossContingenciesCurrent_84B1795DF0A3C13C9474E244A8FED8DC" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AccruedEnvironmentalLossContingenciesCurrent_84B1795DF0A3C13C9474E244A8FED8DC" xlink:to="lab_us-gaap_AccruedEnvironmentalLossContingenciesCurrent_84B1795DF0A3C13C9474E244A8FED8DC" xlink:type="arc" />
    <link:label id="lab_us-gaap_AccrualForEnvironmentalLossContingenciesPayments1_64C2AFEEB22EB76C379EE244A8FEFD04_terseLabel_en-US" xlink:label="lab_us-gaap_AccrualForEnvironmentalLossContingenciesPayments1_64C2AFEEB22EB76C379EE244A8FEFD04" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Payments related to remediation expenses applied against the reserve</link:label>
    <link:label id="lab_us-gaap_AccrualForEnvironmentalLossContingenciesPayments1_64C2AFEEB22EB76C379EE244A8FEFD04_label_en-US" xlink:label="lab_us-gaap_AccrualForEnvironmentalLossContingenciesPayments1_64C2AFEEB22EB76C379EE244A8FEFD04" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Accrual for Environmental Loss Contingencies, Payments</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AccrualForEnvironmentalLossContingenciesPayments1" xlink:label="loc_us-gaap_AccrualForEnvironmentalLossContingenciesPayments1_64C2AFEEB22EB76C379EE244A8FEFD04" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AccrualForEnvironmentalLossContingenciesPayments1_64C2AFEEB22EB76C379EE244A8FEFD04" xlink:to="lab_us-gaap_AccrualForEnvironmentalLossContingenciesPayments1_64C2AFEEB22EB76C379EE244A8FEFD04" xlink:type="arc" />
    <link:label id="lab_arnc_PercentageOfCostOfGoodsSold_EFC89ECEF734B51B63F9E244A8FE73CB_terseLabel_en-US" xlink:label="lab_arnc_PercentageOfCostOfGoodsSold_EFC89ECEF734B51B63F9E244A8FE73CB" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Percentage of cost of goods sold</link:label>
    <link:label id="lab_arnc_PercentageOfCostOfGoodsSold_EFC89ECEF734B51B63F9E244A8FE73CB_label_en-US" xlink:label="lab_arnc_PercentageOfCostOfGoodsSold_EFC89ECEF734B51B63F9E244A8FE73CB" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Percentage Of Cost Of Goods Sold</link:label>
    <link:label id="lab_arnc_PercentageOfCostOfGoodsSold_EFC89ECEF734B51B63F9E244A8FE73CB_documentation_en-US" xlink:label="lab_arnc_PercentageOfCostOfGoodsSold_EFC89ECEF734B51B63F9E244A8FE73CB" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Percentage of cost of goods sold.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_PercentageOfCostOfGoodsSold" xlink:label="loc_arnc_PercentageOfCostOfGoodsSold_EFC89ECEF734B51B63F9E244A8FE73CB" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_PercentageOfCostOfGoodsSold_EFC89ECEF734B51B63F9E244A8FE73CB" xlink:to="lab_arnc_PercentageOfCostOfGoodsSold_EFC89ECEF734B51B63F9E244A8FE73CB" xlink:type="arc" />
    <link:label id="lab_arnc_ActualRemediationFieldworkPeriod_E4424918F3E620741C25E244A8FEF1A7_terseLabel_en-US" xlink:label="lab_arnc_ActualRemediationFieldworkPeriod_E4424918F3E620741C25E244A8FEF1A7" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Actual remediation fieldwork period</link:label>
    <link:label id="lab_arnc_ActualRemediationFieldworkPeriod_E4424918F3E620741C25E244A8FEF1A7_label_en-US" xlink:label="lab_arnc_ActualRemediationFieldworkPeriod_E4424918F3E620741C25E244A8FEF1A7" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Actual Remediation Fieldwork Period</link:label>
    <link:label id="lab_arnc_ActualRemediationFieldworkPeriod_E4424918F3E620741C25E244A8FEF1A7_documentation_en-US" xlink:label="lab_arnc_ActualRemediationFieldworkPeriod_E4424918F3E620741C25E244A8FEF1A7" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Actual remediation fieldwork period.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_ActualRemediationFieldworkPeriod" xlink:label="loc_arnc_ActualRemediationFieldworkPeriod_E4424918F3E620741C25E244A8FEF1A7" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_ActualRemediationFieldworkPeriod_E4424918F3E620741C25E244A8FEF1A7" xlink:to="lab_arnc_ActualRemediationFieldworkPeriod_E4424918F3E620741C25E244A8FEF1A7" xlink:type="arc" />
    <link:label id="lab_arnc_TaxAgreementIndemnificationofUltimateLiabilityPercent_D2645F177E39D8DC8EFEE244A8FE5189_terseLabel_en-US" xlink:label="lab_arnc_TaxAgreementIndemnificationofUltimateLiabilityPercent_D2645F177E39D8DC8EFEE244A8FE5189" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Tax agreement, indemnification of ultimate liability, percent</link:label>
    <link:label id="lab_arnc_TaxAgreementIndemnificationofUltimateLiabilityPercent_D2645F177E39D8DC8EFEE244A8FE5189_label_en-US" xlink:label="lab_arnc_TaxAgreementIndemnificationofUltimateLiabilityPercent_D2645F177E39D8DC8EFEE244A8FE5189" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Tax Agreement, Indemnification of Ultimate Liability, Percent</link:label>
    <link:label id="lab_arnc_TaxAgreementIndemnificationofUltimateLiabilityPercent_D2645F177E39D8DC8EFEE244A8FE5189_documentation_en-US" xlink:label="lab_arnc_TaxAgreementIndemnificationofUltimateLiabilityPercent_D2645F177E39D8DC8EFEE244A8FE5189" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Tax Agreement, Indemnification of Ultimate Liability, Percent</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_TaxAgreementIndemnificationofUltimateLiabilityPercent" xlink:label="loc_arnc_TaxAgreementIndemnificationofUltimateLiabilityPercent_D2645F177E39D8DC8EFEE244A8FE5189" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_TaxAgreementIndemnificationofUltimateLiabilityPercent_D2645F177E39D8DC8EFEE244A8FE5189" xlink:to="lab_arnc_TaxAgreementIndemnificationofUltimateLiabilityPercent_D2645F177E39D8DC8EFEE244A8FE5189" xlink:type="arc" />
    <link:label id="lab_arnc_IncomeTaxExaminationAssessmentOutstanding_DEE9362315C06D71DA39E244A8FED507_terseLabel_en-US" xlink:label="lab_arnc_IncomeTaxExaminationAssessmentOutstanding_DEE9362315C06D71DA39E244A8FED507" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Total combined assessments</link:label>
    <link:label id="lab_arnc_IncomeTaxExaminationAssessmentOutstanding_DEE9362315C06D71DA39E244A8FED507_label_en-US" xlink:label="lab_arnc_IncomeTaxExaminationAssessmentOutstanding_DEE9362315C06D71DA39E244A8FED507" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Income Tax Examination Assessment Outstanding</link:label>
    <link:label id="lab_arnc_IncomeTaxExaminationAssessmentOutstanding_DEE9362315C06D71DA39E244A8FED507_documentation_en-US" xlink:label="lab_arnc_IncomeTaxExaminationAssessmentOutstanding_DEE9362315C06D71DA39E244A8FED507" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Income tax examination assessment outstanding.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_IncomeTaxExaminationAssessmentOutstanding" xlink:label="loc_arnc_IncomeTaxExaminationAssessmentOutstanding_DEE9362315C06D71DA39E244A8FED507" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_IncomeTaxExaminationAssessmentOutstanding_DEE9362315C06D71DA39E244A8FED507" xlink:to="lab_arnc_IncomeTaxExaminationAssessmentOutstanding_DEE9362315C06D71DA39E244A8FED507" xlink:type="arc" />
    <link:label id="lab_us-gaap_IncreaseDecreaseInReserveForCommissionsExpenseAndTaxes_5F8F3930A378D221FA04E244A8FEF98F_terseLabel_en-US" xlink:label="lab_us-gaap_IncreaseDecreaseInReserveForCommissionsExpenseAndTaxes_5F8F3930A378D221FA04E244A8FEF98F" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Income tax reserve</link:label>
    <link:label id="lab_us-gaap_IncreaseDecreaseInReserveForCommissionsExpenseAndTaxes_5F8F3930A378D221FA04E244A8FEF98F_label_en-US" xlink:label="lab_us-gaap_IncreaseDecreaseInReserveForCommissionsExpenseAndTaxes_5F8F3930A378D221FA04E244A8FEF98F" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Increase (Decrease) in Reserve for Commissions, Expense and Taxes</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_IncreaseDecreaseInReserveForCommissionsExpenseAndTaxes" xlink:label="loc_us-gaap_IncreaseDecreaseInReserveForCommissionsExpenseAndTaxes_5F8F3930A378D221FA04E244A8FEF98F" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncreaseDecreaseInReserveForCommissionsExpenseAndTaxes_5F8F3930A378D221FA04E244A8FEF98F" xlink:to="lab_us-gaap_IncreaseDecreaseInReserveForCommissionsExpenseAndTaxes_5F8F3930A378D221FA04E244A8FEF98F" xlink:type="arc" />
    <link:label id="lab_us-gaap_IncomeTaxReceivable_BACB72EE9F8B77FE6E7DE244A8FE8221_terseLabel_en-US" xlink:label="lab_us-gaap_IncomeTaxReceivable_BACB72EE9F8B77FE6E7DE244A8FE8221" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Income taxes receivable</link:label>
    <link:label id="lab_us-gaap_IncomeTaxReceivable_BACB72EE9F8B77FE6E7DE244A8FE8221_label_en-US" xlink:label="lab_us-gaap_IncomeTaxReceivable_BACB72EE9F8B77FE6E7DE244A8FE8221" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Income Taxes Receivable</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_IncomeTaxReceivable" xlink:label="loc_us-gaap_IncomeTaxReceivable_BACB72EE9F8B77FE6E7DE244A8FE8221" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncomeTaxReceivable_BACB72EE9F8B77FE6E7DE244A8FE8221" xlink:to="lab_us-gaap_IncomeTaxReceivable_BACB72EE9F8B77FE6E7DE244A8FE8221" xlink:type="arc" />
    <link:label id="lab_us-gaap_AssetImpairmentCharges_75F7EC2FD3EEABAA45A3BA4BBE9B90EA_verboseLabel_en-US" xlink:label="lab_us-gaap_AssetImpairmentCharges_75F7EC2FD3EEABAA45A3BA4BBE9B90EA" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Asset impairments</link:label>
    <link:label id="lab_us-gaap_AssetImpairmentCharges_75F7EC2FD3EEABAA45A3BA4BBE9B90EA_label_en-US" xlink:label="lab_us-gaap_AssetImpairmentCharges_75F7EC2FD3EEABAA45A3BA4BBE9B90EA" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Asset Impairment Charges</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AssetImpairmentCharges" xlink:label="loc_us-gaap_AssetImpairmentCharges_75F7EC2FD3EEABAA45A3BA4BBE9B90EA" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AssetImpairmentCharges_75F7EC2FD3EEABAA45A3BA4BBE9B90EA" xlink:to="lab_us-gaap_AssetImpairmentCharges_75F7EC2FD3EEABAA45A3BA4BBE9B90EA" xlink:type="arc" />
    <link:label id="lab_us-gaap_SeveranceCosts1_F39BE51DDBFCF0D90BF3BA4BBE9BA1C8_terseLabel_en-US" xlink:label="lab_us-gaap_SeveranceCosts1_F39BE51DDBFCF0D90BF3BA4BBE9BA1C8" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Layoff costs</link:label>
    <link:label id="lab_us-gaap_SeveranceCosts1_F39BE51DDBFCF0D90BF3BA4BBE9BA1C8_label_en-US" xlink:label="lab_us-gaap_SeveranceCosts1_F39BE51DDBFCF0D90BF3BA4BBE9BA1C8" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Severance Costs</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_SeveranceCosts1" xlink:label="loc_us-gaap_SeveranceCosts1_F39BE51DDBFCF0D90BF3BA4BBE9BA1C8" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SeveranceCosts1_F39BE51DDBFCF0D90BF3BA4BBE9BA1C8" xlink:to="lab_us-gaap_SeveranceCosts1_F39BE51DDBFCF0D90BF3BA4BBE9BA1C8" xlink:type="arc" />
    <link:label id="lab_us-gaap_PensionAndOtherPostretirementBenefitsExpenseReversalOfExpenseNoncash_FF6E014C6F0765065CB4BA4BBE9B108D_terseLabel_en-US" xlink:label="lab_us-gaap_PensionAndOtherPostretirementBenefitsExpenseReversalOfExpenseNoncash_FF6E014C6F0765065CB4BA4BBE9B108D" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Pension and Other postretirement benefits - net settlement and curtailment charges</link:label>
    <link:label id="lab_us-gaap_PensionAndOtherPostretirementBenefitsExpenseReversalOfExpenseNoncash_FF6E014C6F0765065CB4BA4BBE9B108D_label_en-US" xlink:label="lab_us-gaap_PensionAndOtherPostretirementBenefitsExpenseReversalOfExpenseNoncash_FF6E014C6F0765065CB4BA4BBE9B108D" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Pension and Other Postretirement Benefits Expense (Reversal of Expense), Noncash</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PensionAndOtherPostretirementBenefitsExpenseReversalOfExpenseNoncash" xlink:label="loc_us-gaap_PensionAndOtherPostretirementBenefitsExpenseReversalOfExpenseNoncash_FF6E014C6F0765065CB4BA4BBE9B108D" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PensionAndOtherPostretirementBenefitsExpenseReversalOfExpenseNoncash_FF6E014C6F0765065CB4BA4BBE9B108D" xlink:to="lab_us-gaap_PensionAndOtherPostretirementBenefitsExpenseReversalOfExpenseNoncash_FF6E014C6F0765065CB4BA4BBE9B108D" xlink:type="arc" />
    <link:label id="lab_us-gaap_GainLossOnSaleOfBusiness_25590F9F7214E4F880E3BA4BBE9BD794_negatedLabel_en-US" xlink:label="lab_us-gaap_GainLossOnSaleOfBusiness_25590F9F7214E4F880E3BA4BBE9BD794" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xml:lang="en-US">Net (gain) loss on divestitures of assets and businesses (T)</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_GainLossOnSaleOfBusiness" xlink:label="loc_us-gaap_GainLossOnSaleOfBusiness_25590F9F7214E4F880E3BA4BBE9BD794" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_GainLossOnSaleOfBusiness_25590F9F7214E4F880E3BA4BBE9BD794" xlink:to="lab_us-gaap_GainLossOnSaleOfBusiness_25590F9F7214E4F880E3BA4BBE9BD794" xlink:type="arc" />
    <link:label id="lab_arnc_OtherCostsRelatedToRestructuring_370EA6149E5C6F577D3EBA4BBE9B9484_terseLabel_en-US" xlink:label="lab_arnc_OtherCostsRelatedToRestructuring_370EA6149E5C6F577D3EBA4BBE9B9484" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Other</link:label>
    <link:label id="lab_arnc_OtherCostsRelatedToRestructuring_370EA6149E5C6F577D3EBA4BBE9B9484_label_en-US" xlink:label="lab_arnc_OtherCostsRelatedToRestructuring_370EA6149E5C6F577D3EBA4BBE9B9484" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Other Costs Related To Restructuring</link:label>
    <link:label id="lab_arnc_OtherCostsRelatedToRestructuring_370EA6149E5C6F577D3EBA4BBE9B9484_documentation_en-US" xlink:label="lab_arnc_OtherCostsRelatedToRestructuring_370EA6149E5C6F577D3EBA4BBE9B9484" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Other costs related to restructuring.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_OtherCostsRelatedToRestructuring" xlink:label="loc_arnc_OtherCostsRelatedToRestructuring_370EA6149E5C6F577D3EBA4BBE9B9484" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_OtherCostsRelatedToRestructuring_370EA6149E5C6F577D3EBA4BBE9B9484" xlink:to="lab_arnc_OtherCostsRelatedToRestructuring_370EA6149E5C6F577D3EBA4BBE9B9484" xlink:type="arc" />
    <link:label id="lab_arnc_ReversalsOfPreviouslyRecordedLayoff_95FBCB0A9635D97E973BBA4BBE9B2BC4_negatedLabel_en-US" xlink:label="lab_arnc_ReversalsOfPreviouslyRecordedLayoff_95FBCB0A9635D97E973BBA4BBE9B2BC4" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xml:lang="en-US">Reversals of previously recorded layoff costs</link:label>
    <link:label id="lab_arnc_ReversalsOfPreviouslyRecordedLayoff_95FBCB0A9635D97E973BBA4BBE9B2BC4_label_en-US" xlink:label="lab_arnc_ReversalsOfPreviouslyRecordedLayoff_95FBCB0A9635D97E973BBA4BBE9B2BC4" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Reversals Of Previously Recorded Layoff</link:label>
    <link:label id="lab_arnc_ReversalsOfPreviouslyRecordedLayoff_95FBCB0A9635D97E973BBA4BBE9B2BC4_documentation_en-US" xlink:label="lab_arnc_ReversalsOfPreviouslyRecordedLayoff_95FBCB0A9635D97E973BBA4BBE9B2BC4" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Reversals of previously recorded layoff.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_ReversalsOfPreviouslyRecordedLayoff" xlink:label="loc_arnc_ReversalsOfPreviouslyRecordedLayoff_95FBCB0A9635D97E973BBA4BBE9B2BC4" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_ReversalsOfPreviouslyRecordedLayoff_95FBCB0A9635D97E973BBA4BBE9B2BC4" xlink:to="lab_arnc_ReversalsOfPreviouslyRecordedLayoff_95FBCB0A9635D97E973BBA4BBE9B2BC4" xlink:type="arc" />
    <link:label id="lab_us-gaap_RestructuringCharges_68D0595CD20A94F06274BA4BBE9B7E07_totalLabel_en-US" xlink:label="lab_us-gaap_RestructuringCharges_68D0595CD20A94F06274BA4BBE9B7E07" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Restructuring and other charges</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RestructuringCharges" xlink:label="loc_us-gaap_RestructuringCharges_68D0595CD20A94F06274BA4BBE9B7E07" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RestructuringCharges_68D0595CD20A94F06274BA4BBE9B7E07" xlink:to="lab_us-gaap_RestructuringCharges_68D0595CD20A94F06274BA4BBE9B7E07" xlink:type="arc" />
    <link:label id="lab_us-gaap_ScheduleOfAccumulatedOtherComprehensiveIncomeLossTableTextBlock_8F8E66A33E362AE107137C362D928A5B_terseLabel_en-US" xlink:label="lab_us-gaap_ScheduleOfAccumulatedOtherComprehensiveIncomeLossTableTextBlock_8F8E66A33E362AE107137C362D928A5B" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Summary of Changes in Accumulated Other Comprehensive (Loss) by Component</link:label>
    <link:label id="lab_us-gaap_ScheduleOfAccumulatedOtherComprehensiveIncomeLossTableTextBlock_8F8E66A33E362AE107137C362D928A5B_label_en-US" xlink:label="lab_us-gaap_ScheduleOfAccumulatedOtherComprehensiveIncomeLossTableTextBlock_8F8E66A33E362AE107137C362D928A5B" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Schedule of Accumulated Other Comprehensive Income (Loss) [Table Text Block]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ScheduleOfAccumulatedOtherComprehensiveIncomeLossTableTextBlock" xlink:label="loc_us-gaap_ScheduleOfAccumulatedOtherComprehensiveIncomeLossTableTextBlock_8F8E66A33E362AE107137C362D928A5B" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfAccumulatedOtherComprehensiveIncomeLossTableTextBlock_8F8E66A33E362AE107137C362D928A5B" xlink:to="lab_us-gaap_ScheduleOfAccumulatedOtherComprehensiveIncomeLossTableTextBlock_8F8E66A33E362AE107137C362D928A5B" xlink:type="arc" />
    <link:label id="lab_arnc_DeferredTaxAssetsDepreciation_D40213882F97BAC6A0AEC94A9FB6E12A_terseLabel_en-US" xlink:label="lab_arnc_DeferredTaxAssetsDepreciation_D40213882F97BAC6A0AEC94A9FB6E12A" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Deferred tax assets, depreciation</link:label>
    <link:label id="lab_arnc_DeferredTaxAssetsDepreciation_D40213882F97BAC6A0AEC94A9FB6E12A_label_en-US" xlink:label="lab_arnc_DeferredTaxAssetsDepreciation_D40213882F97BAC6A0AEC94A9FB6E12A" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Deferred Tax Assets Depreciation</link:label>
    <link:label id="lab_arnc_DeferredTaxAssetsDepreciation_D40213882F97BAC6A0AEC94A9FB6E12A_documentation_en-US" xlink:label="lab_arnc_DeferredTaxAssetsDepreciation_D40213882F97BAC6A0AEC94A9FB6E12A" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Deferred tax assets, depreciation.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_DeferredTaxAssetsDepreciation" xlink:label="loc_arnc_DeferredTaxAssetsDepreciation_D40213882F97BAC6A0AEC94A9FB6E12A" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_DeferredTaxAssetsDepreciation_D40213882F97BAC6A0AEC94A9FB6E12A" xlink:to="lab_arnc_DeferredTaxAssetsDepreciation_D40213882F97BAC6A0AEC94A9FB6E12A" xlink:type="arc" />
    <link:label id="lab_us-gaap_DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsEmployeeBenefits_760E633E3D9C26C069D5C94A9FB614CF_terseLabel_en-US" xlink:label="lab_us-gaap_DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsEmployeeBenefits_760E633E3D9C26C069D5C94A9FB614CF" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Deferred tax assets, employee benefits</link:label>
    <link:label id="lab_us-gaap_DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsEmployeeBenefits_760E633E3D9C26C069D5C94A9FB614CF_label_en-US" xlink:label="lab_us-gaap_DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsEmployeeBenefits_760E633E3D9C26C069D5C94A9FB614CF" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Deferred Tax Assets, Tax Deferred Expense, Compensation and Benefits, Employee Benefits</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsEmployeeBenefits" xlink:label="loc_us-gaap_DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsEmployeeBenefits_760E633E3D9C26C069D5C94A9FB614CF" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsEmployeeBenefits_760E633E3D9C26C069D5C94A9FB614CF" xlink:to="lab_us-gaap_DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsEmployeeBenefits_760E633E3D9C26C069D5C94A9FB614CF" xlink:type="arc" />
    <link:label id="lab_us-gaap_DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsLossReserves_4C6EEE3BC509339D4459C94A9FB6D5D0_terseLabel_en-US" xlink:label="lab_us-gaap_DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsLossReserves_4C6EEE3BC509339D4459C94A9FB6D5D0" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Deferred tax assets, loss provisions</link:label>
    <link:label id="lab_us-gaap_DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsLossReserves_4C6EEE3BC509339D4459C94A9FB6D5D0_label_en-US" xlink:label="lab_us-gaap_DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsLossReserves_4C6EEE3BC509339D4459C94A9FB6D5D0" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Deferred Tax Assets, Tax Deferred Expense, Reserves and Accruals, Loss Reserves</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsLossReserves" xlink:label="loc_us-gaap_DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsLossReserves_4C6EEE3BC509339D4459C94A9FB6D5D0" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsLossReserves_4C6EEE3BC509339D4459C94A9FB6D5D0" xlink:to="lab_us-gaap_DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsLossReserves_4C6EEE3BC509339D4459C94A9FB6D5D0" xlink:type="arc" />
    <link:label id="lab_us-gaap_DeferredTaxAssetsDeferredIncome_B10CC6DDCA710C987536C94A9FB63F08_terseLabel_en-US" xlink:label="lab_us-gaap_DeferredTaxAssetsDeferredIncome_B10CC6DDCA710C987536C94A9FB63F08" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Deferred tax assets, deferred income</link:label>
    <link:label id="lab_us-gaap_DeferredTaxAssetsDeferredIncome_B10CC6DDCA710C987536C94A9FB63F08_label_en-US" xlink:label="lab_us-gaap_DeferredTaxAssetsDeferredIncome_B10CC6DDCA710C987536C94A9FB63F08" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Deferred Tax Assets, Deferred Income</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DeferredTaxAssetsDeferredIncome" xlink:label="loc_us-gaap_DeferredTaxAssetsDeferredIncome_B10CC6DDCA710C987536C94A9FB63F08" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DeferredTaxAssetsDeferredIncome_B10CC6DDCA710C987536C94A9FB63F08" xlink:to="lab_us-gaap_DeferredTaxAssetsDeferredIncome_B10CC6DDCA710C987536C94A9FB63F08" xlink:type="arc" />
    <link:label id="lab_us-gaap_DeferredTaxAssetsOperatingLossCarryforwards_DDA922AA2A320B03C75AC94A9FB6076F_terseLabel_en-US" xlink:label="lab_us-gaap_DeferredTaxAssetsOperatingLossCarryforwards_DDA922AA2A320B03C75AC94A9FB6076F" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Deferred tax assets, tax loss carryforwards</link:label>
    <link:label id="lab_us-gaap_DeferredTaxAssetsOperatingLossCarryforwards_DDA922AA2A320B03C75AC94A9FB6076F_label_en-US" xlink:label="lab_us-gaap_DeferredTaxAssetsOperatingLossCarryforwards_DDA922AA2A320B03C75AC94A9FB6076F" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Deferred Tax Assets, Operating Loss Carryforwards</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DeferredTaxAssetsOperatingLossCarryforwards" xlink:label="loc_us-gaap_DeferredTaxAssetsOperatingLossCarryforwards_DDA922AA2A320B03C75AC94A9FB6076F" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DeferredTaxAssetsOperatingLossCarryforwards_DDA922AA2A320B03C75AC94A9FB6076F" xlink:to="lab_us-gaap_DeferredTaxAssetsOperatingLossCarryforwards_DDA922AA2A320B03C75AC94A9FB6076F" xlink:type="arc" />
    <link:label id="lab_us-gaap_DeferredTaxAssetsTaxCreditCarryforwards_39AB71899B2A12709EB9C94A9FB70945_terseLabel_en-US" xlink:label="lab_us-gaap_DeferredTaxAssetsTaxCreditCarryforwards_39AB71899B2A12709EB9C94A9FB70945" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Deferred tax assets, tax credit carryforwards</link:label>
    <link:label id="lab_us-gaap_DeferredTaxAssetsTaxCreditCarryforwards_39AB71899B2A12709EB9C94A9FB70945_label_en-US" xlink:label="lab_us-gaap_DeferredTaxAssetsTaxCreditCarryforwards_39AB71899B2A12709EB9C94A9FB70945" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Deferred Tax Assets, Tax Credit Carryforwards</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DeferredTaxAssetsTaxCreditCarryforwards" xlink:label="loc_us-gaap_DeferredTaxAssetsTaxCreditCarryforwards_39AB71899B2A12709EB9C94A9FB70945" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DeferredTaxAssetsTaxCreditCarryforwards_39AB71899B2A12709EB9C94A9FB70945" xlink:to="lab_us-gaap_DeferredTaxAssetsTaxCreditCarryforwards_39AB71899B2A12709EB9C94A9FB70945" xlink:type="arc" />
    <link:label id="lab_us-gaap_DeferredTaxAssetsOther_E802951177969B2EB130C94A9FB7DD3E_verboseLabel_en-US" xlink:label="lab_us-gaap_DeferredTaxAssetsOther_E802951177969B2EB130C94A9FB7DD3E" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Deferred tax assets, other</link:label>
    <link:label id="lab_us-gaap_DeferredTaxAssetsOther_E802951177969B2EB130C94A9FB7DD3E_label_en-US" xlink:label="lab_us-gaap_DeferredTaxAssetsOther_E802951177969B2EB130C94A9FB7DD3E" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Deferred Tax Assets, Other</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DeferredTaxAssetsOther" xlink:label="loc_us-gaap_DeferredTaxAssetsOther_E802951177969B2EB130C94A9FB7DD3E" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DeferredTaxAssetsOther_E802951177969B2EB130C94A9FB7DD3E" xlink:to="lab_us-gaap_DeferredTaxAssetsOther_E802951177969B2EB130C94A9FB7DD3E" xlink:type="arc" />
    <link:label id="lab_us-gaap_DeferredTaxAssetsGross_CB452C656D414845E1F4C94A9FB71D3A_totalLabel_en-US" xlink:label="lab_us-gaap_DeferredTaxAssetsGross_CB452C656D414845E1F4C94A9FB71D3A" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Deferred tax assets, gross</link:label>
    <link:label id="lab_us-gaap_DeferredTaxAssetsGross_CB452C656D414845E1F4C94A9FB71D3A_label_en-US" xlink:label="lab_us-gaap_DeferredTaxAssetsGross_CB452C656D414845E1F4C94A9FB71D3A" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Deferred Tax Assets, Gross</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DeferredTaxAssetsGross" xlink:label="loc_us-gaap_DeferredTaxAssetsGross_CB452C656D414845E1F4C94A9FB71D3A" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DeferredTaxAssetsGross_CB452C656D414845E1F4C94A9FB71D3A" xlink:to="lab_us-gaap_DeferredTaxAssetsGross_CB452C656D414845E1F4C94A9FB71D3A" xlink:type="arc" />
    <link:label id="lab_us-gaap_DeferredTaxAssetsValuationAllowance_76B765FF1E2DC663E1E2C94A9FB77A59_negatedLabel_en-US" xlink:label="lab_us-gaap_DeferredTaxAssetsValuationAllowance_76B765FF1E2DC663E1E2C94A9FB77A59" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xml:lang="en-US">Valuation allowance</link:label>
    <link:label id="lab_us-gaap_DeferredTaxAssetsValuationAllowance_76B765FF1E2DC663E1E2C94A9FB77A59_label_en-US" xlink:label="lab_us-gaap_DeferredTaxAssetsValuationAllowance_76B765FF1E2DC663E1E2C94A9FB77A59" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Deferred Tax Assets, Valuation Allowance</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DeferredTaxAssetsValuationAllowance" xlink:label="loc_us-gaap_DeferredTaxAssetsValuationAllowance_76B765FF1E2DC663E1E2C94A9FB77A59" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DeferredTaxAssetsValuationAllowance_76B765FF1E2DC663E1E2C94A9FB77A59" xlink:to="lab_us-gaap_DeferredTaxAssetsValuationAllowance_76B765FF1E2DC663E1E2C94A9FB77A59" xlink:type="arc" />
    <link:label id="lab_us-gaap_DeferredTaxAssetsNet_387BAF17D2429C4186CDC94A9FB8A738_totalLabel_en-US" xlink:label="lab_us-gaap_DeferredTaxAssetsNet_387BAF17D2429C4186CDC94A9FB8A738" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Deferred tax assets, net</link:label>
    <link:label id="lab_us-gaap_DeferredTaxAssetsNet_387BAF17D2429C4186CDC94A9FB8A738_label_en-US" xlink:label="lab_us-gaap_DeferredTaxAssetsNet_387BAF17D2429C4186CDC94A9FB8A738" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Deferred Tax Assets, Net of Valuation Allowance</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DeferredTaxAssetsNet" xlink:label="loc_us-gaap_DeferredTaxAssetsNet_387BAF17D2429C4186CDC94A9FB8A738" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DeferredTaxAssetsNet_387BAF17D2429C4186CDC94A9FB8A738" xlink:to="lab_us-gaap_DeferredTaxAssetsNet_387BAF17D2429C4186CDC94A9FB8A738" xlink:type="arc" />
    <link:label id="lab_arnc_DeferredTaxLiabilitiesDepreciation_6B84511D72927161B059C94A9FB87E18_terseLabel_en-US" xlink:label="lab_arnc_DeferredTaxLiabilitiesDepreciation_6B84511D72927161B059C94A9FB87E18" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Deferred tax liabilities, depreciation</link:label>
    <link:label id="lab_arnc_DeferredTaxLiabilitiesDepreciation_6B84511D72927161B059C94A9FB87E18_label_en-US" xlink:label="lab_arnc_DeferredTaxLiabilitiesDepreciation_6B84511D72927161B059C94A9FB87E18" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Deferred Tax Liabilities Depreciation</link:label>
    <link:label id="lab_arnc_DeferredTaxLiabilitiesDepreciation_6B84511D72927161B059C94A9FB87E18_documentation_en-US" xlink:label="lab_arnc_DeferredTaxLiabilitiesDepreciation_6B84511D72927161B059C94A9FB87E18" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Deferred tax liabilities depreciation.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_DeferredTaxLiabilitiesDepreciation" xlink:label="loc_arnc_DeferredTaxLiabilitiesDepreciation_6B84511D72927161B059C94A9FB87E18" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_DeferredTaxLiabilitiesDepreciation_6B84511D72927161B059C94A9FB87E18" xlink:to="lab_arnc_DeferredTaxLiabilitiesDepreciation_6B84511D72927161B059C94A9FB87E18" xlink:type="arc" />
    <link:label id="lab_arnc_DeferredTaxLiabilitiesEmployeeBenefits_B22A31C771DB0DD16527C94A9FB85F7C_terseLabel_en-US" xlink:label="lab_arnc_DeferredTaxLiabilitiesEmployeeBenefits_B22A31C771DB0DD16527C94A9FB85F7C" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Deferred tax liabilities, employee benefits</link:label>
    <link:label id="lab_arnc_DeferredTaxLiabilitiesEmployeeBenefits_B22A31C771DB0DD16527C94A9FB85F7C_label_en-US" xlink:label="lab_arnc_DeferredTaxLiabilitiesEmployeeBenefits_B22A31C771DB0DD16527C94A9FB85F7C" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Deferred Tax Liabilities Employee Benefits</link:label>
    <link:label id="lab_arnc_DeferredTaxLiabilitiesEmployeeBenefits_B22A31C771DB0DD16527C94A9FB85F7C_documentation_en-US" xlink:label="lab_arnc_DeferredTaxLiabilitiesEmployeeBenefits_B22A31C771DB0DD16527C94A9FB85F7C" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Deferred tax liabilities, employee benefits.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_DeferredTaxLiabilitiesEmployeeBenefits" xlink:label="loc_arnc_DeferredTaxLiabilitiesEmployeeBenefits_B22A31C771DB0DD16527C94A9FB85F7C" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_DeferredTaxLiabilitiesEmployeeBenefits_B22A31C771DB0DD16527C94A9FB85F7C" xlink:to="lab_arnc_DeferredTaxLiabilitiesEmployeeBenefits_B22A31C771DB0DD16527C94A9FB85F7C" xlink:type="arc" />
    <link:label id="lab_arnc_DeferredTaxLiabilitiesLossProvisions_EA6758344033CE46220CC94A9FB896EE_terseLabel_en-US" xlink:label="lab_arnc_DeferredTaxLiabilitiesLossProvisions_EA6758344033CE46220CC94A9FB896EE" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Deferred tax liabilities, loss provisions</link:label>
    <link:label id="lab_arnc_DeferredTaxLiabilitiesLossProvisions_EA6758344033CE46220CC94A9FB896EE_label_en-US" xlink:label="lab_arnc_DeferredTaxLiabilitiesLossProvisions_EA6758344033CE46220CC94A9FB896EE" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Deferred Tax Liabilities Loss Provisions</link:label>
    <link:label id="lab_arnc_DeferredTaxLiabilitiesLossProvisions_EA6758344033CE46220CC94A9FB896EE_documentation_en-US" xlink:label="lab_arnc_DeferredTaxLiabilitiesLossProvisions_EA6758344033CE46220CC94A9FB896EE" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Deferred tax liabilities, loss provisions.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_DeferredTaxLiabilitiesLossProvisions" xlink:label="loc_arnc_DeferredTaxLiabilitiesLossProvisions_EA6758344033CE46220CC94A9FB896EE" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_DeferredTaxLiabilitiesLossProvisions_EA6758344033CE46220CC94A9FB896EE" xlink:to="lab_arnc_DeferredTaxLiabilitiesLossProvisions_EA6758344033CE46220CC94A9FB896EE" xlink:type="arc" />
    <link:label id="lab_us-gaap_DeferredTaxLiabilitiesDeferredExpense_14833283C66986C39253C94A9FB82C12_terseLabel_en-US" xlink:label="lab_us-gaap_DeferredTaxLiabilitiesDeferredExpense_14833283C66986C39253C94A9FB82C12" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Deferred tax liabilities, deferred expense</link:label>
    <link:label id="lab_us-gaap_DeferredTaxLiabilitiesDeferredExpense_14833283C66986C39253C94A9FB82C12_label_en-US" xlink:label="lab_us-gaap_DeferredTaxLiabilitiesDeferredExpense_14833283C66986C39253C94A9FB82C12" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Deferred Tax Liabilities, Deferred Expense</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DeferredTaxLiabilitiesDeferredExpense" xlink:label="loc_us-gaap_DeferredTaxLiabilitiesDeferredExpense_14833283C66986C39253C94A9FB82C12" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DeferredTaxLiabilitiesDeferredExpense_14833283C66986C39253C94A9FB82C12" xlink:to="lab_us-gaap_DeferredTaxLiabilitiesDeferredExpense_14833283C66986C39253C94A9FB82C12" xlink:type="arc" />
    <link:label id="lab_arnc_DeferredTaxLiabilitiesTaxLossCarryforwards_4D194BCC45FC0C0DC9A6C94A9FB850BB_terseLabel_en-US" xlink:label="lab_arnc_DeferredTaxLiabilitiesTaxLossCarryforwards_4D194BCC45FC0C0DC9A6C94A9FB850BB" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Deferred tax liabilities, tax loss carryforwards</link:label>
    <link:label id="lab_arnc_DeferredTaxLiabilitiesTaxLossCarryforwards_4D194BCC45FC0C0DC9A6C94A9FB850BB_label_en-US" xlink:label="lab_arnc_DeferredTaxLiabilitiesTaxLossCarryforwards_4D194BCC45FC0C0DC9A6C94A9FB850BB" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Deferred Tax Liabilities Tax Loss Carryforwards</link:label>
    <link:label id="lab_arnc_DeferredTaxLiabilitiesTaxLossCarryforwards_4D194BCC45FC0C0DC9A6C94A9FB850BB_documentation_en-US" xlink:label="lab_arnc_DeferredTaxLiabilitiesTaxLossCarryforwards_4D194BCC45FC0C0DC9A6C94A9FB850BB" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Deferred tax liabilities, tax loss carryforwards.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_DeferredTaxLiabilitiesTaxLossCarryforwards" xlink:label="loc_arnc_DeferredTaxLiabilitiesTaxLossCarryforwards_4D194BCC45FC0C0DC9A6C94A9FB850BB" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_DeferredTaxLiabilitiesTaxLossCarryforwards_4D194BCC45FC0C0DC9A6C94A9FB850BB" xlink:to="lab_arnc_DeferredTaxLiabilitiesTaxLossCarryforwards_4D194BCC45FC0C0DC9A6C94A9FB850BB" xlink:type="arc" />
    <link:label id="lab_arnc_DeferredTaxLiabilitiesTaxCreditCarryforwards_F1E66419CEB21E7EE64AC94A9FB943E3_terseLabel_en-US" xlink:label="lab_arnc_DeferredTaxLiabilitiesTaxCreditCarryforwards_F1E66419CEB21E7EE64AC94A9FB943E3" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Deferred tax liabilities, tax credit carryforwards</link:label>
    <link:label id="lab_arnc_DeferredTaxLiabilitiesTaxCreditCarryforwards_F1E66419CEB21E7EE64AC94A9FB943E3_label_en-US" xlink:label="lab_arnc_DeferredTaxLiabilitiesTaxCreditCarryforwards_F1E66419CEB21E7EE64AC94A9FB943E3" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Deferred Tax Liabilities Tax Credit Carryforwards</link:label>
    <link:label id="lab_arnc_DeferredTaxLiabilitiesTaxCreditCarryforwards_F1E66419CEB21E7EE64AC94A9FB943E3_documentation_en-US" xlink:label="lab_arnc_DeferredTaxLiabilitiesTaxCreditCarryforwards_F1E66419CEB21E7EE64AC94A9FB943E3" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Deferred tax liabilities, tax credit carryforwards.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_DeferredTaxLiabilitiesTaxCreditCarryforwards" xlink:label="loc_arnc_DeferredTaxLiabilitiesTaxCreditCarryforwards_F1E66419CEB21E7EE64AC94A9FB943E3" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_DeferredTaxLiabilitiesTaxCreditCarryforwards_F1E66419CEB21E7EE64AC94A9FB943E3" xlink:to="lab_arnc_DeferredTaxLiabilitiesTaxCreditCarryforwards_F1E66419CEB21E7EE64AC94A9FB943E3" xlink:type="arc" />
    <link:label id="lab_us-gaap_DeferredTaxLiabilitiesOther_2FE925804C61F9849B84C94A9FB95F2F_terseLabel_en-US" xlink:label="lab_us-gaap_DeferredTaxLiabilitiesOther_2FE925804C61F9849B84C94A9FB95F2F" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Deferred tax liabilities, other</link:label>
    <link:label id="lab_us-gaap_DeferredTaxLiabilitiesOther_2FE925804C61F9849B84C94A9FB95F2F_label_en-US" xlink:label="lab_us-gaap_DeferredTaxLiabilitiesOther_2FE925804C61F9849B84C94A9FB95F2F" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Deferred Tax Liabilities, Other</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DeferredTaxLiabilitiesOther" xlink:label="loc_us-gaap_DeferredTaxLiabilitiesOther_2FE925804C61F9849B84C94A9FB95F2F" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DeferredTaxLiabilitiesOther_2FE925804C61F9849B84C94A9FB95F2F" xlink:to="lab_us-gaap_DeferredTaxLiabilitiesOther_2FE925804C61F9849B84C94A9FB95F2F" xlink:type="arc" />
    <link:label id="lab_arnc_DeferredTaxLiabilitiesGross_0A9316180DF40EFB49A1C94A9FBAA631_totalLabel_en-US" xlink:label="lab_arnc_DeferredTaxLiabilitiesGross_0A9316180DF40EFB49A1C94A9FBAA631" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Deferred tax liabilities, gross</link:label>
    <link:label id="lab_arnc_DeferredTaxLiabilitiesGross_0A9316180DF40EFB49A1C94A9FBAA631_label_en-US" xlink:label="lab_arnc_DeferredTaxLiabilitiesGross_0A9316180DF40EFB49A1C94A9FBAA631" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Deferred Tax Liabilities Gross</link:label>
    <link:label id="lab_arnc_DeferredTaxLiabilitiesGross_0A9316180DF40EFB49A1C94A9FBAA631_documentation_en-US" xlink:label="lab_arnc_DeferredTaxLiabilitiesGross_0A9316180DF40EFB49A1C94A9FBAA631" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Deferred tax liabilities gross.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_DeferredTaxLiabilitiesGross" xlink:label="loc_arnc_DeferredTaxLiabilitiesGross_0A9316180DF40EFB49A1C94A9FBAA631" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_DeferredTaxLiabilitiesGross_0A9316180DF40EFB49A1C94A9FBAA631" xlink:to="lab_arnc_DeferredTaxLiabilitiesGross_0A9316180DF40EFB49A1C94A9FBAA631" xlink:type="arc" />
    <link:label id="lab_arnc_DeferredTaxLiabilitiesValuationAllowance_35419D4BA0269EA84D61C94A9FBA207B_negatedTerseLabel_en-US" xlink:label="lab_arnc_DeferredTaxLiabilitiesValuationAllowance_35419D4BA0269EA84D61C94A9FBA207B" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:type="resource" xml:lang="en-US">Deferred tax liabilities, valuation allowance</link:label>
    <link:label id="lab_arnc_DeferredTaxLiabilitiesValuationAllowance_35419D4BA0269EA84D61C94A9FBA207B_label_en-US" xlink:label="lab_arnc_DeferredTaxLiabilitiesValuationAllowance_35419D4BA0269EA84D61C94A9FBA207B" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Deferred Tax Liabilities Valuation Allowance</link:label>
    <link:label id="lab_arnc_DeferredTaxLiabilitiesValuationAllowance_35419D4BA0269EA84D61C94A9FBA207B_documentation_en-US" xlink:label="lab_arnc_DeferredTaxLiabilitiesValuationAllowance_35419D4BA0269EA84D61C94A9FBA207B" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Deferred tax liabilities valuation allowance.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_DeferredTaxLiabilitiesValuationAllowance" xlink:label="loc_arnc_DeferredTaxLiabilitiesValuationAllowance_35419D4BA0269EA84D61C94A9FBA207B" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_DeferredTaxLiabilitiesValuationAllowance_35419D4BA0269EA84D61C94A9FBA207B" xlink:to="lab_arnc_DeferredTaxLiabilitiesValuationAllowance_35419D4BA0269EA84D61C94A9FBA207B" xlink:type="arc" />
    <link:label id="lab_us-gaap_DeferredTaxLiabilities_05745A99F6234A158454C94A9FBA1E4B_totalLabel_en-US" xlink:label="lab_us-gaap_DeferredTaxLiabilities_05745A99F6234A158454C94A9FBA1E4B" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Deferred tax liabilities, net</link:label>
    <link:label id="lab_us-gaap_DeferredTaxLiabilities_05745A99F6234A158454C94A9FBA1E4B_label_en-US" xlink:label="lab_us-gaap_DeferredTaxLiabilities_05745A99F6234A158454C94A9FBA1E4B" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Deferred Tax Liabilities, Net</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DeferredTaxLiabilities" xlink:label="loc_us-gaap_DeferredTaxLiabilities_05745A99F6234A158454C94A9FBA1E4B" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DeferredTaxLiabilities_05745A99F6234A158454C94A9FBA1E4B" xlink:to="lab_us-gaap_DeferredTaxLiabilities_05745A99F6234A158454C94A9FBA1E4B" xlink:type="arc" />
    <link:label id="lab_us-gaap_CashFlowSupplementalDisclosuresTextBlock_751087B833CB3B0A85037C362CF5DFB0_terseLabel_en-US" xlink:label="lab_us-gaap_CashFlowSupplementalDisclosuresTextBlock_751087B833CB3B0A85037C362CF5DFB0" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Cash Flow Information</link:label>
    <link:label id="lab_us-gaap_CashFlowSupplementalDisclosuresTextBlock_751087B833CB3B0A85037C362CF5DFB0_label_en-US" xlink:label="lab_us-gaap_CashFlowSupplementalDisclosuresTextBlock_751087B833CB3B0A85037C362CF5DFB0" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Cash Flow, Supplemental Disclosures [Text Block]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_CashFlowSupplementalDisclosuresTextBlock" xlink:label="loc_us-gaap_CashFlowSupplementalDisclosuresTextBlock_751087B833CB3B0A85037C362CF5DFB0" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CashFlowSupplementalDisclosuresTextBlock_751087B833CB3B0A85037C362CF5DFB0" xlink:to="lab_us-gaap_CashFlowSupplementalDisclosuresTextBlock_751087B833CB3B0A85037C362CF5DFB0" xlink:type="arc" />
    <link:label id="lab_us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInNextTwelveMonths_E3F48BEA16FC2DAD1033E244A98EEEFE_terseLabel_en-US" xlink:label="lab_us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInNextTwelveMonths_E3F48BEA16FC2DAD1033E244A98EEEFE" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Principal amount of long-term debt maturing in year 2019</link:label>
    <link:label id="lab_us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInNextTwelveMonths_E3F48BEA16FC2DAD1033E244A98EEEFE_label_en-US" xlink:label="lab_us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInNextTwelveMonths_E3F48BEA16FC2DAD1033E244A98EEEFE" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Long-term Debt, Maturities, Repayments of Principal in Next Twelve Months</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInNextTwelveMonths" xlink:label="loc_us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInNextTwelveMonths_E3F48BEA16FC2DAD1033E244A98EEEFE" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInNextTwelveMonths_E3F48BEA16FC2DAD1033E244A98EEEFE" xlink:to="lab_us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInNextTwelveMonths_E3F48BEA16FC2DAD1033E244A98EEEFE" xlink:type="arc" />
    <link:label id="lab_us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearTwo_683EF9625FC3AB951E14E244A98ED946_terseLabel_en-US" xlink:label="lab_us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearTwo_683EF9625FC3AB951E14E244A98ED946" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Principal amount of long-term debt maturing in year 2020</link:label>
    <link:label id="lab_us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearTwo_683EF9625FC3AB951E14E244A98ED946_label_en-US" xlink:label="lab_us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearTwo_683EF9625FC3AB951E14E244A98ED946" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Long-term Debt, Maturities, Repayments of Principal in Year Two</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearTwo" xlink:label="loc_us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearTwo_683EF9625FC3AB951E14E244A98ED946" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearTwo_683EF9625FC3AB951E14E244A98ED946" xlink:to="lab_us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearTwo_683EF9625FC3AB951E14E244A98ED946" xlink:type="arc" />
    <link:label id="lab_us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearThree_DDC7E130A74A7E47D63DE244A98EF8B0_terseLabel_en-US" xlink:label="lab_us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearThree_DDC7E130A74A7E47D63DE244A98EF8B0" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Principal amount of long-term debt maturing in year 2021</link:label>
    <link:label id="lab_us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearThree_DDC7E130A74A7E47D63DE244A98EF8B0_label_en-US" xlink:label="lab_us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearThree_DDC7E130A74A7E47D63DE244A98EF8B0" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Long-term Debt, Maturities, Repayments of Principal in Year Three</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearThree" xlink:label="loc_us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearThree_DDC7E130A74A7E47D63DE244A98EF8B0" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearThree_DDC7E130A74A7E47D63DE244A98EF8B0" xlink:to="lab_us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearThree_DDC7E130A74A7E47D63DE244A98EF8B0" xlink:type="arc" />
    <link:label id="lab_us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFour_ADECA182658B804814DCE244A98ED388_terseLabel_en-US" xlink:label="lab_us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFour_ADECA182658B804814DCE244A98ED388" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Principal amount of long-term debt maturing in year 2022</link:label>
    <link:label id="lab_us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFour_ADECA182658B804814DCE244A98ED388_label_en-US" xlink:label="lab_us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFour_ADECA182658B804814DCE244A98ED388" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Long-term Debt, Maturities, Repayments of Principal in Year Four</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFour" xlink:label="loc_us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFour_ADECA182658B804814DCE244A98ED388" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFour_ADECA182658B804814DCE244A98ED388" xlink:to="lab_us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFour_ADECA182658B804814DCE244A98ED388" xlink:type="arc" />
    <link:label id="lab_us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFive_E100EC0181E2C2FF3B11E244A98EED4E_terseLabel_en-US" xlink:label="lab_us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFive_E100EC0181E2C2FF3B11E244A98EED4E" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Principal amount of long-term debt maturing in year 2023</link:label>
    <link:label id="lab_us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFive_E100EC0181E2C2FF3B11E244A98EED4E_label_en-US" xlink:label="lab_us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFive_E100EC0181E2C2FF3B11E244A98EED4E" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Long-term Debt, Maturities, Repayments of Principal in Year Five</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFive" xlink:label="loc_us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFive_E100EC0181E2C2FF3B11E244A98EED4E" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFive_E100EC0181E2C2FF3B11E244A98EED4E" xlink:to="lab_us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFive_E100EC0181E2C2FF3B11E244A98EED4E" xlink:type="arc" />
    <link:label id="lab_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosureTextBlock_37D7BDA518389C93E116E244A95E8405_terseLabel_en-US" xlink:label="lab_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosureTextBlock_37D7BDA518389C93E116E244A95E8405" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Other Financial Instruments</link:label>
    <link:label id="lab_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosureTextBlock_37D7BDA518389C93E116E244A95E8405_label_en-US" xlink:label="lab_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosureTextBlock_37D7BDA518389C93E116E244A95E8405" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Derivative Instruments and Hedging Activities Disclosure [Text Block]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosureTextBlock" xlink:label="loc_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosureTextBlock_37D7BDA518389C93E116E244A95E8405" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosureTextBlock_37D7BDA518389C93E116E244A95E8405" xlink:to="lab_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosureTextBlock_37D7BDA518389C93E116E244A95E8405" xlink:type="arc" />
    <link:label id="lab_us-gaap_ScheduleOfStockByClassTable_5684C705FB84AE74D2FB0D84AA7812AD_terseLabel_en-US" xlink:label="lab_us-gaap_ScheduleOfStockByClassTable_5684C705FB84AE74D2FB0D84AA7812AD" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Schedule of Stock by Class [Table]</link:label>
    <link:label id="lab_us-gaap_ScheduleOfStockByClassTable_5684C705FB84AE74D2FB0D84AA7812AD_label_en-US" xlink:label="lab_us-gaap_ScheduleOfStockByClassTable_5684C705FB84AE74D2FB0D84AA7812AD" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Schedule of Stock by Class [Table]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ScheduleOfStockByClassTable" xlink:label="loc_us-gaap_ScheduleOfStockByClassTable_5684C705FB84AE74D2FB0D84AA7812AD" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfStockByClassTable_5684C705FB84AE74D2FB0D84AA7812AD" xlink:to="lab_us-gaap_ScheduleOfStockByClassTable_5684C705FB84AE74D2FB0D84AA7812AD" xlink:type="arc" />
    <link:label id="lab_us-gaap_ConvertibleDebtMember_8310BBB1B2023EF2582B0DA0D1751684_terseLabel_en-US" xlink:label="lab_us-gaap_ConvertibleDebtMember_8310BBB1B2023EF2582B0DA0D1751684" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Convertible Debt</link:label>
    <link:label id="lab_us-gaap_ConvertibleDebtMember_8310BBB1B2023EF2582B0DA0D1751684_label_en-US" xlink:label="lab_us-gaap_ConvertibleDebtMember_8310BBB1B2023EF2582B0DA0D1751684" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Convertible Debt [Member]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ConvertibleDebtMember" xlink:label="loc_us-gaap_ConvertibleDebtMember_8310BBB1B2023EF2582B0DA0D1751684" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ConvertibleDebtMember_8310BBB1B2023EF2582B0DA0D1751684" xlink:to="lab_us-gaap_ConvertibleDebtMember_8310BBB1B2023EF2582B0DA0D1751684" xlink:type="arc" />
    <link:label id="lab_arnc_TrancheDueDecember2015Member_7A1691AF2BDF0B71A3F70DA9D18C0687_terseLabel_en-US" xlink:label="lab_arnc_TrancheDueDecember2015Member_7A1691AF2BDF0B71A3F70DA9D18C0687" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Tranche Due December 2015</link:label>
    <link:label id="lab_arnc_TrancheDueDecember2015Member_7A1691AF2BDF0B71A3F70DA9D18C0687_label_en-US" xlink:label="lab_arnc_TrancheDueDecember2015Member_7A1691AF2BDF0B71A3F70DA9D18C0687" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Tranche Due December 2015 [Member]</link:label>
    <link:label id="lab_arnc_TrancheDueDecember2015Member_7A1691AF2BDF0B71A3F70DA9D18C0687_documentation_en-US" xlink:label="lab_arnc_TrancheDueDecember2015Member_7A1691AF2BDF0B71A3F70DA9D18C0687" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Tranche Due December 2015 [Member]</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_TrancheDueDecember2015Member" xlink:label="loc_arnc_TrancheDueDecember2015Member_7A1691AF2BDF0B71A3F70DA9D18C0687" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_TrancheDueDecember2015Member_7A1691AF2BDF0B71A3F70DA9D18C0687" xlink:to="lab_arnc_TrancheDueDecember2015Member_7A1691AF2BDF0B71A3F70DA9D18C0687" xlink:type="arc" />
    <link:label id="lab_arnc_TrancheDueOctober2019Member_0EAC9D87C73BCD0937A20DA1896B6FAA_terseLabel_en-US" xlink:label="lab_arnc_TrancheDueOctober2019Member_0EAC9D87C73BCD0937A20DA1896B6FAA" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Tranche Due October 2019</link:label>
    <link:label id="lab_arnc_TrancheDueOctober2019Member_0EAC9D87C73BCD0937A20DA1896B6FAA_label_en-US" xlink:label="lab_arnc_TrancheDueOctober2019Member_0EAC9D87C73BCD0937A20DA1896B6FAA" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Tranche Due October 2019 [Member]</link:label>
    <link:label id="lab_arnc_TrancheDueOctober2019Member_0EAC9D87C73BCD0937A20DA1896B6FAA_documentation_en-US" xlink:label="lab_arnc_TrancheDueOctober2019Member_0EAC9D87C73BCD0937A20DA1896B6FAA" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Tranche Due October 2019 [Member]</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_TrancheDueOctober2019Member" xlink:label="loc_arnc_TrancheDueOctober2019Member_0EAC9D87C73BCD0937A20DA1896B6FAA" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_TrancheDueOctober2019Member_0EAC9D87C73BCD0937A20DA1896B6FAA" xlink:to="lab_arnc_TrancheDueOctober2019Member_0EAC9D87C73BCD0937A20DA1896B6FAA" xlink:type="arc" />
    <link:label id="lab_us-gaap_AwardDateAxis_EE346AFDD13559161FE40D84AA78F240_terseLabel_en-US" xlink:label="lab_us-gaap_AwardDateAxis_EE346AFDD13559161FE40D84AA78F240" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Award Date [Axis]</link:label>
    <link:label id="lab_us-gaap_AwardDateAxis_EE346AFDD13559161FE40D84AA78F240_label_en-US" xlink:label="lab_us-gaap_AwardDateAxis_EE346AFDD13559161FE40D84AA78F240" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Award Date [Axis]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AwardDateAxis" xlink:label="loc_us-gaap_AwardDateAxis_EE346AFDD13559161FE40D84AA78F240" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AwardDateAxis_EE346AFDD13559161FE40D84AA78F240" xlink:to="lab_us-gaap_AwardDateAxis_EE346AFDD13559161FE40D84AA78F240" xlink:type="arc" />
    <link:label id="lab_us-gaap_AwardDateDomain_47593723D01D9C43DDCD0D84AA785BE9_terseLabel_en-US" xlink:label="lab_us-gaap_AwardDateDomain_47593723D01D9C43DDCD0D84AA785BE9" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Award Date [Domain]</link:label>
    <link:label id="lab_us-gaap_AwardDateDomain_47593723D01D9C43DDCD0D84AA785BE9_label_en-US" xlink:label="lab_us-gaap_AwardDateDomain_47593723D01D9C43DDCD0D84AA785BE9" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Award Date [Domain]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AwardDateDomain" xlink:label="loc_us-gaap_AwardDateDomain_47593723D01D9C43DDCD0D84AA785BE9" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AwardDateDomain_47593723D01D9C43DDCD0D84AA785BE9" xlink:to="lab_us-gaap_AwardDateDomain_47593723D01D9C43DDCD0D84AA785BE9" xlink:type="arc" />
    <link:label id="lab_arnc_TwentySeventeenAwardsMember_A0E5F62DDF00E6B5EABE0D84AA78E320_terseLabel_en-US" xlink:label="lab_arnc_TwentySeventeenAwardsMember_A0E5F62DDF00E6B5EABE0D84AA78E320" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Twenty Seventeen Awards</link:label>
    <link:label id="lab_arnc_TwentySeventeenAwardsMember_A0E5F62DDF00E6B5EABE0D84AA78E320_label_en-US" xlink:label="lab_arnc_TwentySeventeenAwardsMember_A0E5F62DDF00E6B5EABE0D84AA78E320" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Twenty Seventeen Awards [Member]</link:label>
    <link:label id="lab_arnc_TwentySeventeenAwardsMember_A0E5F62DDF00E6B5EABE0D84AA78E320_documentation_en-US" xlink:label="lab_arnc_TwentySeventeenAwardsMember_A0E5F62DDF00E6B5EABE0D84AA78E320" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Twenty Seventeen Awards [Member]</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_TwentySeventeenAwardsMember" xlink:label="loc_arnc_TwentySeventeenAwardsMember_A0E5F62DDF00E6B5EABE0D84AA78E320" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_TwentySeventeenAwardsMember_A0E5F62DDF00E6B5EABE0D84AA78E320" xlink:to="lab_arnc_TwentySeventeenAwardsMember_A0E5F62DDF00E6B5EABE0D84AA78E320" xlink:type="arc" />
    <link:label id="lab_arnc_TwentyFifteenAndTwentySixteenAwardsMember_0A3B781C5926856CF5A20D84AA782792_terseLabel_en-US" xlink:label="lab_arnc_TwentyFifteenAndTwentySixteenAwardsMember_0A3B781C5926856CF5A20D84AA782792" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Twenty Fifteen And Twenty Sixteen Awards</link:label>
    <link:label id="lab_arnc_TwentyFifteenAndTwentySixteenAwardsMember_0A3B781C5926856CF5A20D84AA782792_label_en-US" xlink:label="lab_arnc_TwentyFifteenAndTwentySixteenAwardsMember_0A3B781C5926856CF5A20D84AA782792" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Twenty Fifteen And Twenty Sixteen Awards [Member]</link:label>
    <link:label id="lab_arnc_TwentyFifteenAndTwentySixteenAwardsMember_0A3B781C5926856CF5A20D84AA782792_documentation_en-US" xlink:label="lab_arnc_TwentyFifteenAndTwentySixteenAwardsMember_0A3B781C5926856CF5A20D84AA782792" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Twenty Fifteen And Twenty Sixteen Awards [Member]</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_TwentyFifteenAndTwentySixteenAwardsMember" xlink:label="loc_arnc_TwentyFifteenAndTwentySixteenAwardsMember_0A3B781C5926856CF5A20D84AA782792" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_TwentyFifteenAndTwentySixteenAwardsMember_0A3B781C5926856CF5A20D84AA782792" xlink:to="lab_arnc_TwentyFifteenAndTwentySixteenAwardsMember_0A3B781C5926856CF5A20D84AA782792" xlink:type="arc" />
    <link:label id="lab_us-gaap_VestingAxis_32746A07F8F665C9B87B0D84AA7807B4_terseLabel_en-US" xlink:label="lab_us-gaap_VestingAxis_32746A07F8F665C9B87B0D84AA7807B4" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Vesting [Axis]</link:label>
    <link:label id="lab_us-gaap_VestingAxis_32746A07F8F665C9B87B0D84AA7807B4_label_en-US" xlink:label="lab_us-gaap_VestingAxis_32746A07F8F665C9B87B0D84AA7807B4" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Vesting [Axis]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_VestingAxis" xlink:label="loc_us-gaap_VestingAxis_32746A07F8F665C9B87B0D84AA7807B4" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_VestingAxis_32746A07F8F665C9B87B0D84AA7807B4" xlink:to="lab_us-gaap_VestingAxis_32746A07F8F665C9B87B0D84AA7807B4" xlink:type="arc" />
    <link:label id="lab_us-gaap_VestingDomain_57648092107D42EAD8440D84AA784187_terseLabel_en-US" xlink:label="lab_us-gaap_VestingDomain_57648092107D42EAD8440D84AA784187" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Vesting [Domain]</link:label>
    <link:label id="lab_us-gaap_VestingDomain_57648092107D42EAD8440D84AA784187_label_en-US" xlink:label="lab_us-gaap_VestingDomain_57648092107D42EAD8440D84AA784187" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Vesting [Domain]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_VestingDomain" xlink:label="loc_us-gaap_VestingDomain_57648092107D42EAD8440D84AA784187" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_VestingDomain_57648092107D42EAD8440D84AA784187" xlink:to="lab_us-gaap_VestingDomain_57648092107D42EAD8440D84AA784187" xlink:type="arc" />
    <link:label id="lab_us-gaap_ShareBasedCompensationAwardTrancheOneMember_29DD025C97E9ADBAF0400D84AA782175_terseLabel_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationAwardTrancheOneMember_29DD025C97E9ADBAF0400D84AA782175" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Share-based Compensation Award, Tranche One</link:label>
    <link:label id="lab_us-gaap_ShareBasedCompensationAwardTrancheOneMember_29DD025C97E9ADBAF0400D84AA782175_label_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationAwardTrancheOneMember_29DD025C97E9ADBAF0400D84AA782175" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Share-based Compensation Award, Tranche One [Member]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ShareBasedCompensationAwardTrancheOneMember" xlink:label="loc_us-gaap_ShareBasedCompensationAwardTrancheOneMember_29DD025C97E9ADBAF0400D84AA782175" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ShareBasedCompensationAwardTrancheOneMember_29DD025C97E9ADBAF0400D84AA782175" xlink:to="lab_us-gaap_ShareBasedCompensationAwardTrancheOneMember_29DD025C97E9ADBAF0400D84AA782175" xlink:type="arc" />
    <link:label id="lab_us-gaap_ShareBasedCompensationAwardTrancheTwoMember_268023B1760119D253350D84AA785EEF_terseLabel_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationAwardTrancheTwoMember_268023B1760119D253350D84AA785EEF" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Share-based Compensation Award, Tranche Two</link:label>
    <link:label id="lab_us-gaap_ShareBasedCompensationAwardTrancheTwoMember_268023B1760119D253350D84AA785EEF_label_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationAwardTrancheTwoMember_268023B1760119D253350D84AA785EEF" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Share-based Compensation Award, Tranche Two [Member]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ShareBasedCompensationAwardTrancheTwoMember" xlink:label="loc_us-gaap_ShareBasedCompensationAwardTrancheTwoMember_268023B1760119D253350D84AA785EEF" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ShareBasedCompensationAwardTrancheTwoMember_268023B1760119D253350D84AA785EEF" xlink:to="lab_us-gaap_ShareBasedCompensationAwardTrancheTwoMember_268023B1760119D253350D84AA785EEF" xlink:type="arc" />
    <link:label id="lab_us-gaap_ShareBasedCompensationAwardTrancheThreeMember_F5666AF9A49577811AE50D84AA78EC94_terseLabel_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationAwardTrancheThreeMember_F5666AF9A49577811AE50D84AA78EC94" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Share-based Compensation Award, Tranche Three</link:label>
    <link:label id="lab_us-gaap_ShareBasedCompensationAwardTrancheThreeMember_F5666AF9A49577811AE50D84AA78EC94_label_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationAwardTrancheThreeMember_F5666AF9A49577811AE50D84AA78EC94" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Share-based Compensation Award, Tranche Three [Member]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ShareBasedCompensationAwardTrancheThreeMember" xlink:label="loc_us-gaap_ShareBasedCompensationAwardTrancheThreeMember_F5666AF9A49577811AE50D84AA78EC94" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ShareBasedCompensationAwardTrancheThreeMember_F5666AF9A49577811AE50D84AA78EC94" xlink:to="lab_us-gaap_ShareBasedCompensationAwardTrancheThreeMember_F5666AF9A49577811AE50D84AA78EC94" xlink:type="arc" />
    <link:label id="lab_us-gaap_StatementClassOfStockAxis_D17048EF5F4B3E8F69600D84AA78FB07_terseLabel_en-US" xlink:label="lab_us-gaap_StatementClassOfStockAxis_D17048EF5F4B3E8F69600D84AA78FB07" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Class of Stock [Axis]</link:label>
    <link:label id="lab_us-gaap_StatementClassOfStockAxis_D17048EF5F4B3E8F69600D84AA78FB07_label_en-US" xlink:label="lab_us-gaap_StatementClassOfStockAxis_D17048EF5F4B3E8F69600D84AA78FB07" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Class of Stock [Axis]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_StatementClassOfStockAxis" xlink:label="loc_us-gaap_StatementClassOfStockAxis_D17048EF5F4B3E8F69600D84AA78FB07" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_StatementClassOfStockAxis_D17048EF5F4B3E8F69600D84AA78FB07" xlink:to="lab_us-gaap_StatementClassOfStockAxis_D17048EF5F4B3E8F69600D84AA78FB07" xlink:type="arc" />
    <link:label id="lab_us-gaap_ClassOfStockDomain_3B4466BE5364C097AA300D84AA78180D_terseLabel_en-US" xlink:label="lab_us-gaap_ClassOfStockDomain_3B4466BE5364C097AA300D84AA78180D" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Class of Stock [Domain]</link:label>
    <link:label id="lab_us-gaap_ClassOfStockDomain_3B4466BE5364C097AA300D84AA78180D_label_en-US" xlink:label="lab_us-gaap_ClassOfStockDomain_3B4466BE5364C097AA300D84AA78180D" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Class of Stock [Domain]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ClassOfStockDomain" xlink:label="loc_us-gaap_ClassOfStockDomain_3B4466BE5364C097AA300D84AA78180D" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ClassOfStockDomain_3B4466BE5364C097AA300D84AA78180D" xlink:to="lab_us-gaap_ClassOfStockDomain_3B4466BE5364C097AA300D84AA78180D" xlink:type="arc" />
    <link:label id="lab_us-gaap_PreferredClassAMember_110A9988D23ABCD6F18F0D84AA789242_terseLabel_en-US" xlink:label="lab_us-gaap_PreferredClassAMember_110A9988D23ABCD6F18F0D84AA789242" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Preferred Class A</link:label>
    <link:label id="lab_us-gaap_PreferredClassAMember_110A9988D23ABCD6F18F0D84AA789242_label_en-US" xlink:label="lab_us-gaap_PreferredClassAMember_110A9988D23ABCD6F18F0D84AA789242" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Preferred Class A [Member]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PreferredClassAMember" xlink:label="loc_us-gaap_PreferredClassAMember_110A9988D23ABCD6F18F0D84AA789242" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PreferredClassAMember_110A9988D23ABCD6F18F0D84AA789242" xlink:to="lab_us-gaap_PreferredClassAMember_110A9988D23ABCD6F18F0D84AA789242" xlink:type="arc" />
    <link:label id="lab_us-gaap_PreferredClassBMember_CA7D91A06CEFDE2900060D84AA783196_terseLabel_en-US" xlink:label="lab_us-gaap_PreferredClassBMember_CA7D91A06CEFDE2900060D84AA783196" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Preferred Class B</link:label>
    <link:label id="lab_us-gaap_PreferredClassBMember_CA7D91A06CEFDE2900060D84AA783196_label_en-US" xlink:label="lab_us-gaap_PreferredClassBMember_CA7D91A06CEFDE2900060D84AA783196" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Preferred Class B [Member]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PreferredClassBMember" xlink:label="loc_us-gaap_PreferredClassBMember_CA7D91A06CEFDE2900060D84AA783196" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PreferredClassBMember_CA7D91A06CEFDE2900060D84AA783196" xlink:to="lab_us-gaap_PreferredClassBMember_CA7D91A06CEFDE2900060D84AA783196" xlink:type="arc" />
    <link:label id="lab_us-gaap_ScheduleOfSharesSubjectToMandatoryRedemptionBySettlementTermsAxis_E7E3026B398CB70A14000D84AA78021F_terseLabel_en-US" xlink:label="lab_us-gaap_ScheduleOfSharesSubjectToMandatoryRedemptionBySettlementTermsAxis_E7E3026B398CB70A14000D84AA78021F" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Schedule of Financial Instruments Subject to Mandatory Redemption by Settlement Terms [Axis]</link:label>
    <link:label id="lab_us-gaap_ScheduleOfSharesSubjectToMandatoryRedemptionBySettlementTermsAxis_E7E3026B398CB70A14000D84AA78021F_label_en-US" xlink:label="lab_us-gaap_ScheduleOfSharesSubjectToMandatoryRedemptionBySettlementTermsAxis_E7E3026B398CB70A14000D84AA78021F" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Schedule of Financial Instruments Subject to Mandatory Redemption by Settlement Terms [Axis]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ScheduleOfSharesSubjectToMandatoryRedemptionBySettlementTermsAxis" xlink:label="loc_us-gaap_ScheduleOfSharesSubjectToMandatoryRedemptionBySettlementTermsAxis_E7E3026B398CB70A14000D84AA78021F" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfSharesSubjectToMandatoryRedemptionBySettlementTermsAxis_E7E3026B398CB70A14000D84AA78021F" xlink:to="lab_us-gaap_ScheduleOfSharesSubjectToMandatoryRedemptionBySettlementTermsAxis_E7E3026B398CB70A14000D84AA78021F" xlink:type="arc" />
    <link:label id="lab_us-gaap_SharesSubjectToMandatoryRedemptionFinancialInstrumentDomain_D9C3ED9B67DC2FD55DFB0D84AA78C22A_terseLabel_en-US" xlink:label="lab_us-gaap_SharesSubjectToMandatoryRedemptionFinancialInstrumentDomain_D9C3ED9B67DC2FD55DFB0D84AA78C22A" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Financial Instruments Subject to Mandatory Redemption, Financial Instrument [Domain]</link:label>
    <link:label id="lab_us-gaap_SharesSubjectToMandatoryRedemptionFinancialInstrumentDomain_D9C3ED9B67DC2FD55DFB0D84AA78C22A_label_en-US" xlink:label="lab_us-gaap_SharesSubjectToMandatoryRedemptionFinancialInstrumentDomain_D9C3ED9B67DC2FD55DFB0D84AA78C22A" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Financial Instruments Subject to Mandatory Redemption, Financial Instrument [Domain]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_SharesSubjectToMandatoryRedemptionFinancialInstrumentDomain" xlink:label="loc_us-gaap_SharesSubjectToMandatoryRedemptionFinancialInstrumentDomain_D9C3ED9B67DC2FD55DFB0D84AA78C22A" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SharesSubjectToMandatoryRedemptionFinancialInstrumentDomain_D9C3ED9B67DC2FD55DFB0D84AA78C22A" xlink:to="lab_us-gaap_SharesSubjectToMandatoryRedemptionFinancialInstrumentDomain_D9C3ED9B67DC2FD55DFB0D84AA78C22A" xlink:type="arc" />
    <link:label id="lab_arnc_ClassbMandatoryConvertiblePreferredStockMember_6A33E057D26CB7B263AA0D84AA78A3CD_terseLabel_en-US" xlink:label="lab_arnc_ClassbMandatoryConvertiblePreferredStockMember_6A33E057D26CB7B263AA0D84AA78A3CD" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Class B Mandatory Convertible Preferred Stock</link:label>
    <link:label id="lab_arnc_ClassbMandatoryConvertiblePreferredStockMember_6A33E057D26CB7B263AA0D84AA78A3CD_label_en-US" xlink:label="lab_arnc_ClassbMandatoryConvertiblePreferredStockMember_6A33E057D26CB7B263AA0D84AA78A3CD" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Classb Mandatory Convertible Preferred Stock [Member]</link:label>
    <link:label id="lab_arnc_ClassbMandatoryConvertiblePreferredStockMember_6A33E057D26CB7B263AA0D84AA78A3CD_documentation_en-US" xlink:label="lab_arnc_ClassbMandatoryConvertiblePreferredStockMember_6A33E057D26CB7B263AA0D84AA78A3CD" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Classb Mandatory Convertible Preferred Stock [Member]</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_ClassbMandatoryConvertiblePreferredStockMember" xlink:label="loc_arnc_ClassbMandatoryConvertiblePreferredStockMember_6A33E057D26CB7B263AA0D84AA78A3CD" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_ClassbMandatoryConvertiblePreferredStockMember_6A33E057D26CB7B263AA0D84AA78A3CD" xlink:to="lab_arnc_ClassbMandatoryConvertiblePreferredStockMember_6A33E057D26CB7B263AA0D84AA78A3CD" xlink:type="arc" />
    <link:label id="lab_arnc_MandatoryConvertiblePreferredStockMember_B94B25C2DBC7378A70130D84AA78C25D_terseLabel_en-US" xlink:label="lab_arnc_MandatoryConvertiblePreferredStockMember_B94B25C2DBC7378A70130D84AA78C25D" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Mandatory convertible preferred stock</link:label>
    <link:label id="lab_arnc_MandatoryConvertiblePreferredStockMember_B94B25C2DBC7378A70130D84AA78C25D_label_en-US" xlink:label="lab_arnc_MandatoryConvertiblePreferredStockMember_B94B25C2DBC7378A70130D84AA78C25D" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Mandatory Convertible Preferred Stock [Member]</link:label>
    <link:label id="lab_arnc_MandatoryConvertiblePreferredStockMember_B94B25C2DBC7378A70130D84AA78C25D_documentation_en-US" xlink:label="lab_arnc_MandatoryConvertiblePreferredStockMember_B94B25C2DBC7378A70130D84AA78C25D" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Mandatory Convertible Preferred Stock [Member]</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_MandatoryConvertiblePreferredStockMember" xlink:label="loc_arnc_MandatoryConvertiblePreferredStockMember_B94B25C2DBC7378A70130D84AA78C25D" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_MandatoryConvertiblePreferredStockMember_B94B25C2DBC7378A70130D84AA78C25D" xlink:to="lab_arnc_MandatoryConvertiblePreferredStockMember_B94B25C2DBC7378A70130D84AA78C25D" xlink:type="arc" />
    <link:label id="lab_us-gaap_CommonStockMember_A782973C23224C3781770D84AA7893F3_terseLabel_en-US" xlink:label="lab_us-gaap_CommonStockMember_A782973C23224C3781770D84AA7893F3" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Common stock</link:label>
    <link:label id="lab_us-gaap_CommonStockMember_A782973C23224C3781770D84AA7893F3_label_en-US" xlink:label="lab_us-gaap_CommonStockMember_A782973C23224C3781770D84AA7893F3" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Common Stock [Member]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_CommonStockMember" xlink:label="loc_us-gaap_CommonStockMember_A782973C23224C3781770D84AA7893F3" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CommonStockMember_A782973C23224C3781770D84AA7893F3" xlink:to="lab_us-gaap_CommonStockMember_A782973C23224C3781770D84AA7893F3" xlink:type="arc" />
    <link:label id="lab_us-gaap_AdditionalPaidInCapitalMember_C39E2471F07358B6E1870D84AA787C9E_terseLabel_en-US" xlink:label="lab_us-gaap_AdditionalPaidInCapitalMember_C39E2471F07358B6E1870D84AA787C9E" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Additional capital</link:label>
    <link:label id="lab_us-gaap_AdditionalPaidInCapitalMember_C39E2471F07358B6E1870D84AA787C9E_label_en-US" xlink:label="lab_us-gaap_AdditionalPaidInCapitalMember_C39E2471F07358B6E1870D84AA787C9E" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Additional Paid-in Capital [Member]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AdditionalPaidInCapitalMember" xlink:label="loc_us-gaap_AdditionalPaidInCapitalMember_C39E2471F07358B6E1870D84AA787C9E" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AdditionalPaidInCapitalMember_C39E2471F07358B6E1870D84AA787C9E" xlink:to="lab_us-gaap_AdditionalPaidInCapitalMember_C39E2471F07358B6E1870D84AA787C9E" xlink:type="arc" />
    <link:label id="lab_us-gaap_AwardTypeAxis_2C9730D74B9D4F97C9140D84AA78CDCD_terseLabel_en-US" xlink:label="lab_us-gaap_AwardTypeAxis_2C9730D74B9D4F97C9140D84AA78CDCD" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Award Type [Axis]</link:label>
    <link:label id="lab_us-gaap_AwardTypeAxis_2C9730D74B9D4F97C9140D84AA78CDCD_label_en-US" xlink:label="lab_us-gaap_AwardTypeAxis_2C9730D74B9D4F97C9140D84AA78CDCD" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Award Type [Axis]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AwardTypeAxis" xlink:label="loc_us-gaap_AwardTypeAxis_2C9730D74B9D4F97C9140D84AA78CDCD" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AwardTypeAxis_2C9730D74B9D4F97C9140D84AA78CDCD" xlink:to="lab_us-gaap_AwardTypeAxis_2C9730D74B9D4F97C9140D84AA78CDCD" xlink:type="arc" />
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_DFB0F47E6930175FE5170D84AA78CCCF_terseLabel_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_DFB0F47E6930175FE5170D84AA78CCCF" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Equity Award [Domain]</link:label>
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_DFB0F47E6930175FE5170D84AA78CCCF_label_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_DFB0F47E6930175FE5170D84AA78CCCF" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Equity Award [Domain]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_DFB0F47E6930175FE5170D84AA78CCCF" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_DFB0F47E6930175FE5170D84AA78CCCF" xlink:to="lab_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_DFB0F47E6930175FE5170D84AA78CCCF" xlink:type="arc" />
    <link:label id="lab_us-gaap_EmployeeStockOptionMember_1ED7247D435CAABA205E0D84AA7875A3_terseLabel_en-US" xlink:label="lab_us-gaap_EmployeeStockOptionMember_1ED7247D435CAABA205E0D84AA7875A3" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Stock Options</link:label>
    <link:label id="lab_us-gaap_EmployeeStockOptionMember_1ED7247D435CAABA205E0D84AA7875A3_label_en-US" xlink:label="lab_us-gaap_EmployeeStockOptionMember_1ED7247D435CAABA205E0D84AA7875A3" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Employee Stock Option [Member]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_EmployeeStockOptionMember" xlink:label="loc_us-gaap_EmployeeStockOptionMember_1ED7247D435CAABA205E0D84AA7875A3" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_EmployeeStockOptionMember_1ED7247D435CAABA205E0D84AA7875A3" xlink:to="lab_us-gaap_EmployeeStockOptionMember_1ED7247D435CAABA205E0D84AA7875A3" xlink:type="arc" />
    <link:label id="lab_us-gaap_RestrictedStockUnitsRSUMember_C4FAFB5BC504125D435A0D84AA7899AE_terseLabel_en-US" xlink:label="lab_us-gaap_RestrictedStockUnitsRSUMember_C4FAFB5BC504125D435A0D84AA7899AE" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Restricted Stock Units (RSUs)</link:label>
    <link:label id="lab_us-gaap_RestrictedStockUnitsRSUMember_C4FAFB5BC504125D435A0D84AA7899AE_label_en-US" xlink:label="lab_us-gaap_RestrictedStockUnitsRSUMember_C4FAFB5BC504125D435A0D84AA7899AE" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Restricted Stock Units (RSUs) [Member]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RestrictedStockUnitsRSUMember" xlink:label="loc_us-gaap_RestrictedStockUnitsRSUMember_C4FAFB5BC504125D435A0D84AA7899AE" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RestrictedStockUnitsRSUMember_C4FAFB5BC504125D435A0D84AA7899AE" xlink:to="lab_us-gaap_RestrictedStockUnitsRSUMember_C4FAFB5BC504125D435A0D84AA7899AE" xlink:type="arc" />
    <link:label id="lab_arnc_CliffOptionsMember_625899C1D55A073C69500D84AA78E9AD_terseLabel_en-US" xlink:label="lab_arnc_CliffOptionsMember_625899C1D55A073C69500D84AA78E9AD" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Cliff Options</link:label>
    <link:label id="lab_arnc_CliffOptionsMember_625899C1D55A073C69500D84AA78E9AD_label_en-US" xlink:label="lab_arnc_CliffOptionsMember_625899C1D55A073C69500D84AA78E9AD" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Cliff Options [Member]</link:label>
    <link:label id="lab_arnc_CliffOptionsMember_625899C1D55A073C69500D84AA78E9AD_documentation_en-US" xlink:label="lab_arnc_CliffOptionsMember_625899C1D55A073C69500D84AA78E9AD" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Cliff Options [Member]</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_CliffOptionsMember" xlink:label="loc_arnc_CliffOptionsMember_625899C1D55A073C69500D84AA78E9AD" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_CliffOptionsMember_625899C1D55A073C69500D84AA78E9AD" xlink:to="lab_arnc_CliffOptionsMember_625899C1D55A073C69500D84AA78E9AD" xlink:type="arc" />
    <link:label id="lab_us-gaap_PerformanceSharesMember_666C0D227E72D3C3715A0D84AA78F18C_terseLabel_en-US" xlink:label="lab_us-gaap_PerformanceSharesMember_666C0D227E72D3C3715A0D84AA78F18C" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Performance Shares</link:label>
    <link:label id="lab_us-gaap_PerformanceSharesMember_666C0D227E72D3C3715A0D84AA78F18C_label_en-US" xlink:label="lab_us-gaap_PerformanceSharesMember_666C0D227E72D3C3715A0D84AA78F18C" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Performance Shares [Member]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PerformanceSharesMember" xlink:label="loc_us-gaap_PerformanceSharesMember_666C0D227E72D3C3715A0D84AA78F18C" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PerformanceSharesMember_666C0D227E72D3C3715A0D84AA78F18C" xlink:to="lab_us-gaap_PerformanceSharesMember_666C0D227E72D3C3715A0D84AA78F18C" xlink:type="arc" />
    <link:label id="lab_us-gaap_IncomeStatementLocationAxis_2CB906A95B5547C420FF0D84AA788C5B_terseLabel_en-US" xlink:label="lab_us-gaap_IncomeStatementLocationAxis_2CB906A95B5547C420FF0D84AA788C5B" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Income Statement Location [Axis]</link:label>
    <link:label id="lab_us-gaap_IncomeStatementLocationAxis_2CB906A95B5547C420FF0D84AA788C5B_label_en-US" xlink:label="lab_us-gaap_IncomeStatementLocationAxis_2CB906A95B5547C420FF0D84AA788C5B" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Income Statement Location [Axis]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_IncomeStatementLocationAxis" xlink:label="loc_us-gaap_IncomeStatementLocationAxis_2CB906A95B5547C420FF0D84AA788C5B" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncomeStatementLocationAxis_2CB906A95B5547C420FF0D84AA788C5B" xlink:to="lab_us-gaap_IncomeStatementLocationAxis_2CB906A95B5547C420FF0D84AA788C5B" xlink:type="arc" />
    <link:label id="lab_us-gaap_IncomeStatementLocationDomain_340BAADF170FD8F9B12E0D84AA7848CC_terseLabel_en-US" xlink:label="lab_us-gaap_IncomeStatementLocationDomain_340BAADF170FD8F9B12E0D84AA7848CC" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Income Statement Location [Domain]</link:label>
    <link:label id="lab_us-gaap_IncomeStatementLocationDomain_340BAADF170FD8F9B12E0D84AA7848CC_label_en-US" xlink:label="lab_us-gaap_IncomeStatementLocationDomain_340BAADF170FD8F9B12E0D84AA7848CC" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Income Statement Location [Domain]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_IncomeStatementLocationDomain" xlink:label="loc_us-gaap_IncomeStatementLocationDomain_340BAADF170FD8F9B12E0D84AA7848CC" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncomeStatementLocationDomain_340BAADF170FD8F9B12E0D84AA7848CC" xlink:to="lab_us-gaap_IncomeStatementLocationDomain_340BAADF170FD8F9B12E0D84AA7848CC" xlink:type="arc" />
    <link:label id="lab_arnc_RestructuringAndOtherChargesMember_363A0FCDDB17D892A3D60D84AA789D50_terseLabel_en-US" xlink:label="lab_arnc_RestructuringAndOtherChargesMember_363A0FCDDB17D892A3D60D84AA789D50" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Restructuring and Other Charges</link:label>
    <link:label id="lab_arnc_RestructuringAndOtherChargesMember_363A0FCDDB17D892A3D60D84AA789D50_label_en-US" xlink:label="lab_arnc_RestructuringAndOtherChargesMember_363A0FCDDB17D892A3D60D84AA789D50" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Restructuring and Other Charges [Member]</link:label>
    <link:label id="lab_arnc_RestructuringAndOtherChargesMember_363A0FCDDB17D892A3D60D84AA789D50_documentation_en-US" xlink:label="lab_arnc_RestructuringAndOtherChargesMember_363A0FCDDB17D892A3D60D84AA789D50" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Restructuring and other charges.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_RestructuringAndOtherChargesMember" xlink:label="loc_arnc_RestructuringAndOtherChargesMember_363A0FCDDB17D892A3D60D84AA789D50" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_RestructuringAndOtherChargesMember_363A0FCDDB17D892A3D60D84AA789D50" xlink:to="lab_arnc_RestructuringAndOtherChargesMember_363A0FCDDB17D892A3D60D84AA789D50" xlink:type="arc" />
    <link:label id="lab_us-gaap_ClassOfStockLineItems_9D6576E6F81DA486D1240D84AA78F504_terseLabel_en-US" xlink:label="lab_us-gaap_ClassOfStockLineItems_9D6576E6F81DA486D1240D84AA78F504" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Class of Stock [Line Items]</link:label>
    <link:label id="lab_us-gaap_ClassOfStockLineItems_9D6576E6F81DA486D1240D84AA78F504_label_en-US" xlink:label="lab_us-gaap_ClassOfStockLineItems_9D6576E6F81DA486D1240D84AA78F504" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Class of Stock [Line Items]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ClassOfStockLineItems" xlink:label="loc_us-gaap_ClassOfStockLineItems_9D6576E6F81DA486D1240D84AA78F504" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ClassOfStockLineItems_9D6576E6F81DA486D1240D84AA78F504" xlink:to="lab_us-gaap_ClassOfStockLineItems_9D6576E6F81DA486D1240D84AA78F504" xlink:type="arc" />
    <link:label id="lab_us-gaap_PreferredStockNumberOfSharesParValueAndOtherDisclosuresAbstract_E031500284723F71DECE0D84AA789B92_terseLabel_en-US" xlink:label="lab_us-gaap_PreferredStockNumberOfSharesParValueAndOtherDisclosuresAbstract_E031500284723F71DECE0D84AA789B92" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Preferred Stock</link:label>
    <link:label id="lab_us-gaap_PreferredStockNumberOfSharesParValueAndOtherDisclosuresAbstract_E031500284723F71DECE0D84AA789B92_label_en-US" xlink:label="lab_us-gaap_PreferredStockNumberOfSharesParValueAndOtherDisclosuresAbstract_E031500284723F71DECE0D84AA789B92" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Preferred Stock, Number of Shares, Par Value and Other Disclosures [Abstract]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PreferredStockNumberOfSharesParValueAndOtherDisclosuresAbstract" xlink:label="loc_us-gaap_PreferredStockNumberOfSharesParValueAndOtherDisclosuresAbstract_E031500284723F71DECE0D84AA789B92" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PreferredStockNumberOfSharesParValueAndOtherDisclosuresAbstract_E031500284723F71DECE0D84AA789B92" xlink:to="lab_us-gaap_PreferredStockNumberOfSharesParValueAndOtherDisclosuresAbstract_E031500284723F71DECE0D84AA789B92" xlink:type="arc" />
    <link:label id="lab_arnc_PreferredStockNumberOfClasses_3C21C15780ADFC89C66C0D84AA7873E2_terseLabel_en-US" xlink:label="lab_arnc_PreferredStockNumberOfClasses_3C21C15780ADFC89C66C0D84AA7873E2" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Preferred stock, number of classes</link:label>
    <link:label id="lab_arnc_PreferredStockNumberOfClasses_3C21C15780ADFC89C66C0D84AA7873E2_label_en-US" xlink:label="lab_arnc_PreferredStockNumberOfClasses_3C21C15780ADFC89C66C0D84AA7873E2" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Preferred Stock, Number Of Classes</link:label>
    <link:label id="lab_arnc_PreferredStockNumberOfClasses_3C21C15780ADFC89C66C0D84AA7873E2_documentation_en-US" xlink:label="lab_arnc_PreferredStockNumberOfClasses_3C21C15780ADFC89C66C0D84AA7873E2" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Preferred Stock, Number Of Classes</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_PreferredStockNumberOfClasses" xlink:label="loc_arnc_PreferredStockNumberOfClasses_3C21C15780ADFC89C66C0D84AA7873E2" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_PreferredStockNumberOfClasses_3C21C15780ADFC89C66C0D84AA7873E2" xlink:to="lab_arnc_PreferredStockNumberOfClasses_3C21C15780ADFC89C66C0D84AA7873E2" xlink:type="arc" />
    <link:label id="lab_us-gaap_PreferredStockSharesAuthorized_553AA16E52EA1DED668D0D84AA78CF45_terseLabel_en-US" xlink:label="lab_us-gaap_PreferredStockSharesAuthorized_553AA16E52EA1DED668D0D84AA78CF45" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Number of shares of preferred stock authorized (in shares)</link:label>
    <link:label id="lab_us-gaap_PreferredStockSharesAuthorized_553AA16E52EA1DED668D0D84AA78CF45_label_en-US" xlink:label="lab_us-gaap_PreferredStockSharesAuthorized_553AA16E52EA1DED668D0D84AA78CF45" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Preferred Stock, Shares Authorized</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PreferredStockSharesAuthorized" xlink:label="loc_us-gaap_PreferredStockSharesAuthorized_553AA16E52EA1DED668D0D84AA78CF45" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PreferredStockSharesAuthorized_553AA16E52EA1DED668D0D84AA78CF45" xlink:to="lab_us-gaap_PreferredStockSharesAuthorized_553AA16E52EA1DED668D0D84AA78CF45" xlink:type="arc" />
    <link:label id="lab_us-gaap_PreferredStockParOrStatedValuePerShare_2348D73F86BBA0784A410D84AA78B3EC_terseLabel_en-US" xlink:label="lab_us-gaap_PreferredStockParOrStatedValuePerShare_2348D73F86BBA0784A410D84AA78B3EC" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Preferred stock par value (usd per share)</link:label>
    <link:label id="lab_us-gaap_PreferredStockParOrStatedValuePerShare_2348D73F86BBA0784A410D84AA78B3EC_label_en-US" xlink:label="lab_us-gaap_PreferredStockParOrStatedValuePerShare_2348D73F86BBA0784A410D84AA78B3EC" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Preferred Stock, Par or Stated Value Per Share</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PreferredStockParOrStatedValuePerShare" xlink:label="loc_us-gaap_PreferredStockParOrStatedValuePerShare_2348D73F86BBA0784A410D84AA78B3EC" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PreferredStockParOrStatedValuePerShare_2348D73F86BBA0784A410D84AA78B3EC" xlink:to="lab_us-gaap_PreferredStockParOrStatedValuePerShare_2348D73F86BBA0784A410D84AA78B3EC" xlink:type="arc" />
    <link:label id="lab_us-gaap_PreferredStockDividendsPerShareDeclared_3C74F6F3812711D4187E0D84AA781E79_terseLabel_en-US" xlink:label="lab_us-gaap_PreferredStockDividendsPerShareDeclared_3C74F6F3812711D4187E0D84AA781E79" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Preferred stock dividend declared (usd per share)</link:label>
    <link:label id="lab_us-gaap_PreferredStockDividendsPerShareDeclared_3C74F6F3812711D4187E0D84AA781E79_label_en-US" xlink:label="lab_us-gaap_PreferredStockDividendsPerShareDeclared_3C74F6F3812711D4187E0D84AA781E79" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Preferred Stock, Dividends Per Share, Declared</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PreferredStockDividendsPerShareDeclared" xlink:label="loc_us-gaap_PreferredStockDividendsPerShareDeclared_3C74F6F3812711D4187E0D84AA781E79" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PreferredStockDividendsPerShareDeclared_3C74F6F3812711D4187E0D84AA781E79" xlink:to="lab_us-gaap_PreferredStockDividendsPerShareDeclared_3C74F6F3812711D4187E0D84AA781E79" xlink:type="arc" />
    <link:label id="lab_us-gaap_PreferredStockSharesOutstanding_6F57B95B9363FD443D8D0D84AA7851A7_terseLabel_en-US" xlink:label="lab_us-gaap_PreferredStockSharesOutstanding_6F57B95B9363FD443D8D0D84AA7851A7" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Preferred stock, shares outstanding (in shares)</link:label>
    <link:label id="lab_us-gaap_PreferredStockSharesOutstanding_6F57B95B9363FD443D8D0D84AA7851A7_label_en-US" xlink:label="lab_us-gaap_PreferredStockSharesOutstanding_6F57B95B9363FD443D8D0D84AA7851A7" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Preferred Stock, Shares Outstanding</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PreferredStockSharesOutstanding" xlink:label="loc_us-gaap_PreferredStockSharesOutstanding_6F57B95B9363FD443D8D0D84AA7851A7" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PreferredStockSharesOutstanding_6F57B95B9363FD443D8D0D84AA7851A7" xlink:to="lab_us-gaap_PreferredStockSharesOutstanding_6F57B95B9363FD443D8D0D84AA7851A7" xlink:type="arc" />
    <link:label id="lab_us-gaap_SaleOfStockConsiderationReceivedPerTransaction_BC125C5CFCB1C948FB710D84AA788BE3_terseLabel_en-US" xlink:label="lab_us-gaap_SaleOfStockConsiderationReceivedPerTransaction_BC125C5CFCB1C948FB710D84AA788BE3" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Public offering of preferred stock</link:label>
    <link:label id="lab_us-gaap_SaleOfStockConsiderationReceivedPerTransaction_BC125C5CFCB1C948FB710D84AA788BE3_label_en-US" xlink:label="lab_us-gaap_SaleOfStockConsiderationReceivedPerTransaction_BC125C5CFCB1C948FB710D84AA788BE3" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Sale of Stock, Consideration Received Per Transaction</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_SaleOfStockConsiderationReceivedPerTransaction" xlink:label="loc_us-gaap_SaleOfStockConsiderationReceivedPerTransaction_BC125C5CFCB1C948FB710D84AA788BE3" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SaleOfStockConsiderationReceivedPerTransaction_BC125C5CFCB1C948FB710D84AA788BE3" xlink:to="lab_us-gaap_SaleOfStockConsiderationReceivedPerTransaction_BC125C5CFCB1C948FB710D84AA788BE3" xlink:type="arc" />
    <link:label id="lab_us-gaap_SaleOfStockNumberOfSharesIssuedInTransaction_3191CC34C0FEB47178380D84AA782974_verboseLabel_en-US" xlink:label="lab_us-gaap_SaleOfStockNumberOfSharesIssuedInTransaction_3191CC34C0FEB47178380D84AA782974" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Depository shares sold (in shares)</link:label>
    <link:label id="lab_us-gaap_SaleOfStockNumberOfSharesIssuedInTransaction_3191CC34C0FEB47178380D84AA782974_label_en-US" xlink:label="lab_us-gaap_SaleOfStockNumberOfSharesIssuedInTransaction_3191CC34C0FEB47178380D84AA782974" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Sale of Stock, Number of Shares Issued in Transaction</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_SaleOfStockNumberOfSharesIssuedInTransaction" xlink:label="loc_us-gaap_SaleOfStockNumberOfSharesIssuedInTransaction_3191CC34C0FEB47178380D84AA782974" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SaleOfStockNumberOfSharesIssuedInTransaction_3191CC34C0FEB47178380D84AA782974" xlink:to="lab_us-gaap_SaleOfStockNumberOfSharesIssuedInTransaction_3191CC34C0FEB47178380D84AA782974" xlink:type="arc" />
    <link:label id="lab_us-gaap_SaleOfStockPercentageOfOwnershipBeforeTransaction_4495077C6C90BA7DBB5A0D84AA78909D_terseLabel_en-US" xlink:label="lab_us-gaap_SaleOfStockPercentageOfOwnershipBeforeTransaction_4495077C6C90BA7DBB5A0D84AA78909D" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Percentage ownership</link:label>
    <link:label id="lab_us-gaap_SaleOfStockPercentageOfOwnershipBeforeTransaction_4495077C6C90BA7DBB5A0D84AA78909D_label_en-US" xlink:label="lab_us-gaap_SaleOfStockPercentageOfOwnershipBeforeTransaction_4495077C6C90BA7DBB5A0D84AA78909D" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Sale of Stock, Percentage of Ownership before Transaction</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_SaleOfStockPercentageOfOwnershipBeforeTransaction" xlink:label="loc_us-gaap_SaleOfStockPercentageOfOwnershipBeforeTransaction_4495077C6C90BA7DBB5A0D84AA78909D" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SaleOfStockPercentageOfOwnershipBeforeTransaction_4495077C6C90BA7DBB5A0D84AA78909D" xlink:to="lab_us-gaap_SaleOfStockPercentageOfOwnershipBeforeTransaction_4495077C6C90BA7DBB5A0D84AA78909D" xlink:type="arc" />
    <link:label id="lab_us-gaap_PreferredStockLiquidationPreference_6DD7D68E413878D7AC990D84AA7881A1_terseLabel_en-US" xlink:label="lab_us-gaap_PreferredStockLiquidationPreference_6DD7D68E413878D7AC990D84AA7881A1" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Preferred stock liquidation preference (usd per share)</link:label>
    <link:label id="lab_us-gaap_PreferredStockLiquidationPreference_6DD7D68E413878D7AC990D84AA7881A1_label_en-US" xlink:label="lab_us-gaap_PreferredStockLiquidationPreference_6DD7D68E413878D7AC990D84AA7881A1" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Preferred Stock, Liquidation Preference Per Share</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PreferredStockLiquidationPreference" xlink:label="loc_us-gaap_PreferredStockLiquidationPreference_6DD7D68E413878D7AC990D84AA7881A1" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PreferredStockLiquidationPreference_6DD7D68E413878D7AC990D84AA7881A1" xlink:to="lab_us-gaap_PreferredStockLiquidationPreference_6DD7D68E413878D7AC990D84AA7881A1" xlink:type="arc" />
    <link:label id="lab_arnc_InvestmentInPreferredShare_9A9A81C94358FF1C5D4E0D84AA78014B_terseLabel_en-US" xlink:label="lab_arnc_InvestmentInPreferredShare_9A9A81C94358FF1C5D4E0D84AA78014B" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Preferred shares (in shares)</link:label>
    <link:label id="lab_arnc_InvestmentInPreferredShare_9A9A81C94358FF1C5D4E0D84AA78014B_label_en-US" xlink:label="lab_arnc_InvestmentInPreferredShare_9A9A81C94358FF1C5D4E0D84AA78014B" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Investment In Preferred Share</link:label>
    <link:label id="lab_arnc_InvestmentInPreferredShare_9A9A81C94358FF1C5D4E0D84AA78014B_documentation_en-US" xlink:label="lab_arnc_InvestmentInPreferredShare_9A9A81C94358FF1C5D4E0D84AA78014B" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Investment In Preferred Share</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_InvestmentInPreferredShare" xlink:label="loc_arnc_InvestmentInPreferredShare_9A9A81C94358FF1C5D4E0D84AA78014B" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_InvestmentInPreferredShare_9A9A81C94358FF1C5D4E0D84AA78014B" xlink:to="lab_arnc_InvestmentInPreferredShare_9A9A81C94358FF1C5D4E0D84AA78014B" xlink:type="arc" />
    <link:label id="lab_arnc_ProceedsFromIssuancePublicOfferingNetOfOfferingCosts_3BAE37908C67425E167D0D84AA787A4F_terseLabel_en-US" xlink:label="lab_arnc_ProceedsFromIssuancePublicOfferingNetOfOfferingCosts_3BAE37908C67425E167D0D84AA787A4F" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Proceeds from public offering</link:label>
    <link:label id="lab_arnc_ProceedsFromIssuancePublicOfferingNetOfOfferingCosts_3BAE37908C67425E167D0D84AA787A4F_label_en-US" xlink:label="lab_arnc_ProceedsFromIssuancePublicOfferingNetOfOfferingCosts_3BAE37908C67425E167D0D84AA787A4F" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Proceeds From Issuance Public Offering Net Of Offering Costs</link:label>
    <link:label id="lab_arnc_ProceedsFromIssuancePublicOfferingNetOfOfferingCosts_3BAE37908C67425E167D0D84AA787A4F_documentation_en-US" xlink:label="lab_arnc_ProceedsFromIssuancePublicOfferingNetOfOfferingCosts_3BAE37908C67425E167D0D84AA787A4F" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Proceeds From Issuance Public Offering Net Of Offering Costs</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_ProceedsFromIssuancePublicOfferingNetOfOfferingCosts" xlink:label="loc_arnc_ProceedsFromIssuancePublicOfferingNetOfOfferingCosts_3BAE37908C67425E167D0D84AA787A4F" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_ProceedsFromIssuancePublicOfferingNetOfOfferingCosts_3BAE37908C67425E167D0D84AA787A4F" xlink:to="lab_arnc_ProceedsFromIssuancePublicOfferingNetOfOfferingCosts_3BAE37908C67425E167D0D84AA787A4F" xlink:type="arc" />
    <link:label id="lab_arnc_PreferredStockConversionPrice_4C9D7A787F659B07314E0D84AA78CA1C_terseLabel_en-US" xlink:label="lab_arnc_PreferredStockConversionPrice_4C9D7A787F659B07314E0D84AA78CA1C" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Preferred stock conversion price (in usd per share)</link:label>
    <link:label id="lab_arnc_PreferredStockConversionPrice_4C9D7A787F659B07314E0D84AA78CA1C_label_en-US" xlink:label="lab_arnc_PreferredStockConversionPrice_4C9D7A787F659B07314E0D84AA78CA1C" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Preferred Stock Conversion Price</link:label>
    <link:label id="lab_arnc_PreferredStockConversionPrice_4C9D7A787F659B07314E0D84AA78CA1C_documentation_en-US" xlink:label="lab_arnc_PreferredStockConversionPrice_4C9D7A787F659B07314E0D84AA78CA1C" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Preferred Stock Conversion Price</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_PreferredStockConversionPrice" xlink:label="loc_arnc_PreferredStockConversionPrice_4C9D7A787F659B07314E0D84AA78CA1C" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_PreferredStockConversionPrice_4C9D7A787F659B07314E0D84AA78CA1C" xlink:to="lab_arnc_PreferredStockConversionPrice_4C9D7A787F659B07314E0D84AA78CA1C" xlink:type="arc" />
    <link:label id="lab_us-gaap_ConversionOfStockSharesConverted1_8F4B6A174777127AD4FE0D84AA78316B_terseLabel_en-US" xlink:label="lab_us-gaap_ConversionOfStockSharesConverted1_8F4B6A174777127AD4FE0D84AA78316B" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Conversion of stock, shares converted (in shares)</link:label>
    <link:label id="lab_us-gaap_ConversionOfStockSharesConverted1_8F4B6A174777127AD4FE0D84AA78316B_label_en-US" xlink:label="lab_us-gaap_ConversionOfStockSharesConverted1_8F4B6A174777127AD4FE0D84AA78316B" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Conversion of Stock, Shares Converted</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ConversionOfStockSharesConverted1" xlink:label="loc_us-gaap_ConversionOfStockSharesConverted1_8F4B6A174777127AD4FE0D84AA78316B" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ConversionOfStockSharesConverted1_8F4B6A174777127AD4FE0D84AA78316B" xlink:to="lab_us-gaap_ConversionOfStockSharesConverted1_8F4B6A174777127AD4FE0D84AA78316B" xlink:type="arc" />
    <link:label id="lab_us-gaap_PreferredStockDividendsPerShareCashPaid_B9ADE5F225A0D98522630D84AA7847C7_terseLabel_en-US" xlink:label="lab_us-gaap_PreferredStockDividendsPerShareCashPaid_B9ADE5F225A0D98522630D84AA7847C7" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Cash paid for dividends, preferred stock (per share)</link:label>
    <link:label id="lab_us-gaap_PreferredStockDividendsPerShareCashPaid_B9ADE5F225A0D98522630D84AA7847C7_label_en-US" xlink:label="lab_us-gaap_PreferredStockDividendsPerShareCashPaid_B9ADE5F225A0D98522630D84AA7847C7" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Preferred Stock, Dividends, Per Share, Cash Paid</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PreferredStockDividendsPerShareCashPaid" xlink:label="loc_us-gaap_PreferredStockDividendsPerShareCashPaid_B9ADE5F225A0D98522630D84AA7847C7" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PreferredStockDividendsPerShareCashPaid_B9ADE5F225A0D98522630D84AA7847C7" xlink:to="lab_us-gaap_PreferredStockDividendsPerShareCashPaid_B9ADE5F225A0D98522630D84AA7847C7" xlink:type="arc" />
    <link:label id="lab_arnc_PreferredStockConversionRatePerShare_2195EDA9FB03D9B243A00D84AA783273_verboseLabel_en-US" xlink:label="lab_arnc_PreferredStockConversionRatePerShare_2195EDA9FB03D9B243A00D84AA783273" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Preferred stock conversion rate per share</link:label>
    <link:label id="lab_arnc_PreferredStockConversionRatePerShare_2195EDA9FB03D9B243A00D84AA783273_label_en-US" xlink:label="lab_arnc_PreferredStockConversionRatePerShare_2195EDA9FB03D9B243A00D84AA783273" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Preferred Stock Conversion Rate Per Share</link:label>
    <link:label id="lab_arnc_PreferredStockConversionRatePerShare_2195EDA9FB03D9B243A00D84AA783273_documentation_en-US" xlink:label="lab_arnc_PreferredStockConversionRatePerShare_2195EDA9FB03D9B243A00D84AA783273" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Preferred Stock Conversion Rate Per Share</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_PreferredStockConversionRatePerShare" xlink:label="loc_arnc_PreferredStockConversionRatePerShare_2195EDA9FB03D9B243A00D84AA783273" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_PreferredStockConversionRatePerShare_2195EDA9FB03D9B243A00D84AA783273" xlink:to="lab_arnc_PreferredStockConversionRatePerShare_2195EDA9FB03D9B243A00D84AA783273" xlink:type="arc" />
    <link:label id="lab_us-gaap_DividendsPreferredStockStock_49F7BDE32A16BE66865A0D84AA7874F2_terseLabel_en-US" xlink:label="lab_us-gaap_DividendsPreferredStockStock_49F7BDE32A16BE66865A0D84AA7874F2" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Dividends on mandatory convertible preferred stock (usd per share)</link:label>
    <link:label id="lab_us-gaap_DividendsPreferredStockStock_49F7BDE32A16BE66865A0D84AA7874F2_label_en-US" xlink:label="lab_us-gaap_DividendsPreferredStockStock_49F7BDE32A16BE66865A0D84AA7874F2" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Dividends, Preferred Stock, Stock</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DividendsPreferredStockStock" xlink:label="loc_us-gaap_DividendsPreferredStockStock_49F7BDE32A16BE66865A0D84AA7874F2" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DividendsPreferredStockStock_49F7BDE32A16BE66865A0D84AA7874F2" xlink:to="lab_us-gaap_DividendsPreferredStockStock_49F7BDE32A16BE66865A0D84AA7874F2" xlink:type="arc" />
    <link:label id="lab_us-gaap_StockholdersEquityNoteStockSplitConversionRatio1_6679C35AECF9819CF14A0D84AA7830B7_terseLabel_en-US" xlink:label="lab_us-gaap_StockholdersEquityNoteStockSplitConversionRatio1_6679C35AECF9819CF14A0D84AA7830B7" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Reverse stock split ratio</link:label>
    <link:label id="lab_us-gaap_StockholdersEquityNoteStockSplitConversionRatio1_6679C35AECF9819CF14A0D84AA7830B7_label_en-US" xlink:label="lab_us-gaap_StockholdersEquityNoteStockSplitConversionRatio1_6679C35AECF9819CF14A0D84AA7830B7" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Stockholders' Equity Note, Stock Split, Conversion Ratio</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_StockholdersEquityNoteStockSplitConversionRatio1" xlink:label="loc_us-gaap_StockholdersEquityNoteStockSplitConversionRatio1_6679C35AECF9819CF14A0D84AA7830B7" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_StockholdersEquityNoteStockSplitConversionRatio1_6679C35AECF9819CF14A0D84AA7830B7" xlink:to="lab_us-gaap_StockholdersEquityNoteStockSplitConversionRatio1_6679C35AECF9819CF14A0D84AA7830B7" xlink:type="arc" />
    <link:label id="lab_us-gaap_CommonStockNumberOfSharesParValueAndOtherDisclosuresAbstract_42F563964CB956E2C8130D84AA781855_terseLabel_en-US" xlink:label="lab_us-gaap_CommonStockNumberOfSharesParValueAndOtherDisclosuresAbstract_42F563964CB956E2C8130D84AA781855" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Common Stock</link:label>
    <link:label id="lab_us-gaap_CommonStockNumberOfSharesParValueAndOtherDisclosuresAbstract_42F563964CB956E2C8130D84AA781855_label_en-US" xlink:label="lab_us-gaap_CommonStockNumberOfSharesParValueAndOtherDisclosuresAbstract_42F563964CB956E2C8130D84AA781855" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Common Stock, Number of Shares, Par Value and Other Disclosures [Abstract]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_CommonStockNumberOfSharesParValueAndOtherDisclosuresAbstract" xlink:label="loc_us-gaap_CommonStockNumberOfSharesParValueAndOtherDisclosuresAbstract_42F563964CB956E2C8130D84AA781855" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CommonStockNumberOfSharesParValueAndOtherDisclosuresAbstract_42F563964CB956E2C8130D84AA781855" xlink:to="lab_us-gaap_CommonStockNumberOfSharesParValueAndOtherDisclosuresAbstract_42F563964CB956E2C8130D84AA781855" xlink:type="arc" />
    <link:label id="lab_us-gaap_CommonStockSharesOutstanding_E26C4106D506C48D188A0D84AA7851EB_terseLabel_en-US" xlink:label="lab_us-gaap_CommonStockSharesOutstanding_E26C4106D506C48D188A0D84AA7851EB" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Common stock outstanding (in shares)</link:label>
    <link:label id="lab_us-gaap_CommonStockSharesOutstanding_E26C4106D506C48D188A0D84AA7851EB_label_en-US" xlink:label="lab_us-gaap_CommonStockSharesOutstanding_E26C4106D506C48D188A0D84AA7851EB" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Common Stock, Shares, Outstanding</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_CommonStockSharesOutstanding" xlink:label="loc_us-gaap_CommonStockSharesOutstanding_E26C4106D506C48D188A0D84AA7851EB" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CommonStockSharesOutstanding_E26C4106D506C48D188A0D84AA7851EB" xlink:to="lab_us-gaap_CommonStockSharesOutstanding_E26C4106D506C48D188A0D84AA7851EB" xlink:type="arc" />
    <link:label id="lab_us-gaap_CommonStockParOrStatedValuePerShare_6F73E8211844C634D6090D84AA784325_verboseLabel_en-US" xlink:label="lab_us-gaap_CommonStockParOrStatedValuePerShare_6F73E8211844C634D6090D84AA784325" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Common stock, par value per share (usd per share)</link:label>
    <link:label id="lab_us-gaap_CommonStockParOrStatedValuePerShare_6F73E8211844C634D6090D84AA784325_label_en-US" xlink:label="lab_us-gaap_CommonStockParOrStatedValuePerShare_6F73E8211844C634D6090D84AA784325" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Common Stock, Par or Stated Value Per Share</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_CommonStockParOrStatedValuePerShare" xlink:label="loc_us-gaap_CommonStockParOrStatedValuePerShare_6F73E8211844C634D6090D84AA784325" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CommonStockParOrStatedValuePerShare_6F73E8211844C634D6090D84AA784325" xlink:to="lab_us-gaap_CommonStockParOrStatedValuePerShare_6F73E8211844C634D6090D84AA784325" xlink:type="arc" />
    <link:label id="lab_arnc_IncreaseDecreaseInCommonStockDueToReverseStockSplit_48EDDB46731A33DE30CD0D84AA781A96_terseLabel_en-US" xlink:label="lab_arnc_IncreaseDecreaseInCommonStockDueToReverseStockSplit_48EDDB46731A33DE30CD0D84AA781A96" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Common stock decrease</link:label>
    <link:label id="lab_arnc_IncreaseDecreaseInCommonStockDueToReverseStockSplit_48EDDB46731A33DE30CD0D84AA781A96_label_en-US" xlink:label="lab_arnc_IncreaseDecreaseInCommonStockDueToReverseStockSplit_48EDDB46731A33DE30CD0D84AA781A96" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Increase Decrease In Common Stock Due To Reverse Stock Split</link:label>
    <link:label id="lab_arnc_IncreaseDecreaseInCommonStockDueToReverseStockSplit_48EDDB46731A33DE30CD0D84AA781A96_documentation_en-US" xlink:label="lab_arnc_IncreaseDecreaseInCommonStockDueToReverseStockSplit_48EDDB46731A33DE30CD0D84AA781A96" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Increase (decrease) in common stock due to reverse stock split.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_IncreaseDecreaseInCommonStockDueToReverseStockSplit" xlink:label="loc_arnc_IncreaseDecreaseInCommonStockDueToReverseStockSplit_48EDDB46731A33DE30CD0D84AA781A96" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_IncreaseDecreaseInCommonStockDueToReverseStockSplit_48EDDB46731A33DE30CD0D84AA781A96" xlink:to="lab_arnc_IncreaseDecreaseInCommonStockDueToReverseStockSplit_48EDDB46731A33DE30CD0D84AA781A96" xlink:type="arc" />
    <link:label id="lab_us-gaap_CommonStockSharesAuthorized_A69F6096A7BBD93D03470D84AA789A8A_terseLabel_en-US" xlink:label="lab_us-gaap_CommonStockSharesAuthorized_A69F6096A7BBD93D03470D84AA789A8A" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Common stock authorized (in shares)</link:label>
    <link:label id="lab_us-gaap_CommonStockSharesAuthorized_A69F6096A7BBD93D03470D84AA789A8A_label_en-US" xlink:label="lab_us-gaap_CommonStockSharesAuthorized_A69F6096A7BBD93D03470D84AA789A8A" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Common Stock, Shares Authorized</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_CommonStockSharesAuthorized" xlink:label="loc_us-gaap_CommonStockSharesAuthorized_A69F6096A7BBD93D03470D84AA789A8A" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CommonStockSharesAuthorized_A69F6096A7BBD93D03470D84AA789A8A" xlink:to="lab_us-gaap_CommonStockSharesAuthorized_A69F6096A7BBD93D03470D84AA789A8A" xlink:type="arc" />
    <link:label id="lab_us-gaap_TreasuryStockSharesRetired_DE55BFCCAD55A4B864C90D84AA78B43E_terseLabel_en-US" xlink:label="lab_us-gaap_TreasuryStockSharesRetired_DE55BFCCAD55A4B864C90D84AA78B43E" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Treasury stock retirement (in shares)</link:label>
    <link:label id="lab_us-gaap_TreasuryStockSharesRetired_DE55BFCCAD55A4B864C90D84AA78B43E_label_en-US" xlink:label="lab_us-gaap_TreasuryStockSharesRetired_DE55BFCCAD55A4B864C90D84AA78B43E" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Treasury Stock, Shares, Retired</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_TreasuryStockSharesRetired" xlink:label="loc_us-gaap_TreasuryStockSharesRetired_DE55BFCCAD55A4B864C90D84AA78B43E" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_TreasuryStockSharesRetired_DE55BFCCAD55A4B864C90D84AA78B43E" xlink:to="lab_us-gaap_TreasuryStockSharesRetired_DE55BFCCAD55A4B864C90D84AA78B43E" xlink:type="arc" />
    <link:label id="lab_us-gaap_TreasuryStockRetiredCostMethodAmount_18E25BF48F35CDDF9CB00D84AA785A62_terseLabel_en-US" xlink:label="lab_us-gaap_TreasuryStockRetiredCostMethodAmount_18E25BF48F35CDDF9CB00D84AA785A62" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Retirement of treasury stock</link:label>
    <link:label id="lab_us-gaap_TreasuryStockRetiredCostMethodAmount_18E25BF48F35CDDF9CB00D84AA785A62_label_en-US" xlink:label="lab_us-gaap_TreasuryStockRetiredCostMethodAmount_18E25BF48F35CDDF9CB00D84AA785A62" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Treasury Stock, Retired, Cost Method, Amount</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_TreasuryStockRetiredCostMethodAmount" xlink:label="loc_us-gaap_TreasuryStockRetiredCostMethodAmount_18E25BF48F35CDDF9CB00D84AA785A62" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_TreasuryStockRetiredCostMethodAmount_18E25BF48F35CDDF9CB00D84AA785A62" xlink:to="lab_us-gaap_TreasuryStockRetiredCostMethodAmount_18E25BF48F35CDDF9CB00D84AA785A62" xlink:type="arc" />
    <link:label id="lab_us-gaap_TreasuryStockValue_647BC0B44D4748E25FD20D84AA7879EF_terseLabel_en-US" xlink:label="lab_us-gaap_TreasuryStockValue_647BC0B44D4748E25FD20D84AA7879EF" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Treasury stock outstanding</link:label>
    <link:label id="lab_us-gaap_TreasuryStockValue_647BC0B44D4748E25FD20D84AA7879EF_label_en-US" xlink:label="lab_us-gaap_TreasuryStockValue_647BC0B44D4748E25FD20D84AA7879EF" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Treasury Stock, Value</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_TreasuryStockValue" xlink:label="loc_us-gaap_TreasuryStockValue_647BC0B44D4748E25FD20D84AA7879EF" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_TreasuryStockValue_647BC0B44D4748E25FD20D84AA7879EF" xlink:to="lab_us-gaap_TreasuryStockValue_647BC0B44D4748E25FD20D84AA7879EF" xlink:type="arc" />
    <link:label id="lab_arnc_NumberOfRepaymentTranches_4245616D30002D7000690D85AE3E92E1_terseLabel_en-US" xlink:label="lab_arnc_NumberOfRepaymentTranches_4245616D30002D7000690D85AE3E92E1" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Number of repayment tranches</link:label>
    <link:label id="lab_arnc_NumberOfRepaymentTranches_4245616D30002D7000690D85AE3E92E1_label_en-US" xlink:label="lab_arnc_NumberOfRepaymentTranches_4245616D30002D7000690D85AE3E92E1" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Number Of Repayment Tranches</link:label>
    <link:label id="lab_arnc_NumberOfRepaymentTranches_4245616D30002D7000690D85AE3E92E1_documentation_en-US" xlink:label="lab_arnc_NumberOfRepaymentTranches_4245616D30002D7000690D85AE3E92E1" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Number of repayment tranches.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_NumberOfRepaymentTranches" xlink:label="loc_arnc_NumberOfRepaymentTranches_4245616D30002D7000690D85AE3E92E1" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_NumberOfRepaymentTranches_4245616D30002D7000690D85AE3E92E1" xlink:to="lab_arnc_NumberOfRepaymentTranches_4245616D30002D7000690D85AE3E92E1" xlink:type="arc" />
    <link:label id="lab_us-gaap_DebtInstrumentFaceAmount_2E54FF2D0DE0B581737F0D8745EF66E0_terseLabel_en-US" xlink:label="lab_us-gaap_DebtInstrumentFaceAmount_2E54FF2D0DE0B581737F0D8745EF66E0" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Debt instrument, face amount</link:label>
    <link:label id="lab_us-gaap_DebtInstrumentFaceAmount_2E54FF2D0DE0B581737F0D8745EF66E0_label_en-US" xlink:label="lab_us-gaap_DebtInstrumentFaceAmount_2E54FF2D0DE0B581737F0D8745EF66E0" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Debt Instrument, Face Amount</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DebtInstrumentFaceAmount" xlink:label="loc_us-gaap_DebtInstrumentFaceAmount_2E54FF2D0DE0B581737F0D8745EF66E0" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DebtInstrumentFaceAmount_2E54FF2D0DE0B581737F0D8745EF66E0" xlink:to="lab_us-gaap_DebtInstrumentFaceAmount_2E54FF2D0DE0B581737F0D8745EF66E0" xlink:type="arc" />
    <link:label id="lab_arnc_CommonStockSharesIssuedUponConversion_B4141E1FA8A9868339490D8F1C61D8F0_terseLabel_en-US" xlink:label="lab_arnc_CommonStockSharesIssuedUponConversion_B4141E1FA8A9868339490D8F1C61D8F0" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Common stock, number of shares issued upon conversion</link:label>
    <link:label id="lab_arnc_CommonStockSharesIssuedUponConversion_B4141E1FA8A9868339490D8F1C61D8F0_label_en-US" xlink:label="lab_arnc_CommonStockSharesIssuedUponConversion_B4141E1FA8A9868339490D8F1C61D8F0" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Common Stock, Shares, Issued Upon Conversion</link:label>
    <link:label id="lab_arnc_CommonStockSharesIssuedUponConversion_B4141E1FA8A9868339490D8F1C61D8F0_documentation_en-US" xlink:label="lab_arnc_CommonStockSharesIssuedUponConversion_B4141E1FA8A9868339490D8F1C61D8F0" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Common Stock, Shares, Issued Upon Conversion</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_CommonStockSharesIssuedUponConversion" xlink:label="loc_arnc_CommonStockSharesIssuedUponConversion_B4141E1FA8A9868339490D8F1C61D8F0" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_CommonStockSharesIssuedUponConversion_B4141E1FA8A9868339490D8F1C61D8F0" xlink:to="lab_arnc_CommonStockSharesIssuedUponConversion_B4141E1FA8A9868339490D8F1C61D8F0" xlink:type="arc" />
    <link:label id="lab_us-gaap_DebtInstrumentConvertibleConversionRatio1_6901BB112EFCE69B5DC00DA6F74C3116_terseLabel_en-US" xlink:label="lab_us-gaap_DebtInstrumentConvertibleConversionRatio1_6901BB112EFCE69B5DC00DA6F74C3116" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Conversion rate per $1,000 bond (in shares)</link:label>
    <link:label id="lab_us-gaap_DebtInstrumentConvertibleConversionRatio1_6901BB112EFCE69B5DC00DA6F74C3116_label_en-US" xlink:label="lab_us-gaap_DebtInstrumentConvertibleConversionRatio1_6901BB112EFCE69B5DC00DA6F74C3116" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Debt Instrument, Convertible, Conversion Ratio</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DebtInstrumentConvertibleConversionRatio1" xlink:label="loc_us-gaap_DebtInstrumentConvertibleConversionRatio1_6901BB112EFCE69B5DC00DA6F74C3116" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DebtInstrumentConvertibleConversionRatio1_6901BB112EFCE69B5DC00DA6F74C3116" xlink:to="lab_us-gaap_DebtInstrumentConvertibleConversionRatio1_6901BB112EFCE69B5DC00DA6F74C3116" xlink:type="arc" />
    <link:label id="lab_arnc_CommonStockConversionRatePerShare_63FF30FAC131A63DB2940D905696B848_terseLabel_en-US" xlink:label="lab_arnc_CommonStockConversionRatePerShare_63FF30FAC131A63DB2940D905696B848" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Common stock, conversion rate (usd per share)</link:label>
    <link:label id="lab_arnc_CommonStockConversionRatePerShare_63FF30FAC131A63DB2940D905696B848_label_en-US" xlink:label="lab_arnc_CommonStockConversionRatePerShare_63FF30FAC131A63DB2940D905696B848" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Common Stock, Conversion Rate, Per Share</link:label>
    <link:label id="lab_arnc_CommonStockConversionRatePerShare_63FF30FAC131A63DB2940D905696B848_documentation_en-US" xlink:label="lab_arnc_CommonStockConversionRatePerShare_63FF30FAC131A63DB2940D905696B848" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Common Stock, Conversion Rate, Per Share</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_CommonStockConversionRatePerShare" xlink:label="loc_arnc_CommonStockConversionRatePerShare_63FF30FAC131A63DB2940D905696B848" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_CommonStockConversionRatePerShare_63FF30FAC131A63DB2940D905696B848" xlink:to="lab_arnc_CommonStockConversionRatePerShare_63FF30FAC131A63DB2940D905696B848" xlink:type="arc" />
    <link:label id="lab_us-gaap_CommonStockDividendsPerShareDeclared_3234731560293F7D2E950D84AA78843B_verboseLabel_en-US" xlink:label="lab_us-gaap_CommonStockDividendsPerShareDeclared_3234731560293F7D2E950D84AA78843B" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Common stock, dividends yield (usd per share)</link:label>
    <link:label id="lab_us-gaap_CommonStockDividendsPerShareDeclared_3234731560293F7D2E950D84AA78843B_label_en-US" xlink:label="lab_us-gaap_CommonStockDividendsPerShareDeclared_3234731560293F7D2E950D84AA78843B" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Common Stock, Dividends, Per Share, Declared</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_CommonStockDividendsPerShareDeclared" xlink:label="loc_us-gaap_CommonStockDividendsPerShareDeclared_3234731560293F7D2E950D84AA78843B" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CommonStockDividendsPerShareDeclared_3234731560293F7D2E950D84AA78843B" xlink:to="lab_us-gaap_CommonStockDividendsPerShareDeclared_3234731560293F7D2E950D84AA78843B" xlink:type="arc" />
    <link:label id="lab_us-gaap_CommonStockDividendsPerShareCashPaid_8717ABE852C1124E43310D84AA7899D3_terseLabel_en-US" xlink:label="lab_us-gaap_CommonStockDividendsPerShareCashPaid_8717ABE852C1124E43310D84AA7899D3" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Dividends paid per share (usd per share)</link:label>
    <link:label id="lab_us-gaap_CommonStockDividendsPerShareCashPaid_8717ABE852C1124E43310D84AA7899D3_label_en-US" xlink:label="lab_us-gaap_CommonStockDividendsPerShareCashPaid_8717ABE852C1124E43310D84AA7899D3" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Common Stock, Dividends, Per Share, Cash Paid</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_CommonStockDividendsPerShareCashPaid" xlink:label="loc_us-gaap_CommonStockDividendsPerShareCashPaid_8717ABE852C1124E43310D84AA7899D3" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CommonStockDividendsPerShareCashPaid_8717ABE852C1124E43310D84AA7899D3" xlink:to="lab_us-gaap_CommonStockDividendsPerShareCashPaid_8717ABE852C1124E43310D84AA7899D3" xlink:type="arc" />
    <link:label id="lab_us-gaap_CommonStockCapitalSharesReservedForFutureIssuance_BDF3012C4FBAEFCB4CE00D84AA7845E6_terseLabel_en-US" xlink:label="lab_us-gaap_CommonStockCapitalSharesReservedForFutureIssuance_BDF3012C4FBAEFCB4CE00D84AA7845E6" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Common stock reserved for future issuance (in shares)</link:label>
    <link:label id="lab_us-gaap_CommonStockCapitalSharesReservedForFutureIssuance_BDF3012C4FBAEFCB4CE00D84AA7845E6_label_en-US" xlink:label="lab_us-gaap_CommonStockCapitalSharesReservedForFutureIssuance_BDF3012C4FBAEFCB4CE00D84AA7845E6" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Common Stock, Capital Shares Reserved for Future Issuance</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_CommonStockCapitalSharesReservedForFutureIssuance" xlink:label="loc_us-gaap_CommonStockCapitalSharesReservedForFutureIssuance_BDF3012C4FBAEFCB4CE00D84AA7845E6" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CommonStockCapitalSharesReservedForFutureIssuance_BDF3012C4FBAEFCB4CE00D84AA7845E6" xlink:to="lab_us-gaap_CommonStockCapitalSharesReservedForFutureIssuance_BDF3012C4FBAEFCB4CE00D84AA7845E6" xlink:type="arc" />
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant_81D19D97B2C13E8870DC0D84AA7866A7_terseLabel_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant_81D19D97B2C13E8870DC0D84AA7866A7" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Number of shares available for issuance</link:label>
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant_81D19D97B2C13E8870DC0D84AA7866A7_label_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant_81D19D97B2C13E8870DC0D84AA7866A7" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant_81D19D97B2C13E8870DC0D84AA7866A7" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant_81D19D97B2C13E8870DC0D84AA7866A7" xlink:to="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant_81D19D97B2C13E8870DC0D84AA7866A7" xlink:type="arc" />
    <link:label id="lab_us-gaap_ProceedsFromIssuanceOfSharesUnderIncentiveAndShareBasedCompensationPlansIncludingStockOptionsAbstract_6C4617CBBC475F50BA030D84AA789B97_terseLabel_en-US" xlink:label="lab_us-gaap_ProceedsFromIssuanceOfSharesUnderIncentiveAndShareBasedCompensationPlansIncludingStockOptionsAbstract_6C4617CBBC475F50BA030D84AA789B97" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Stock-based Compensation</link:label>
    <link:label id="lab_us-gaap_ProceedsFromIssuanceOfSharesUnderIncentiveAndShareBasedCompensationPlansIncludingStockOptionsAbstract_6C4617CBBC475F50BA030D84AA789B97_label_en-US" xlink:label="lab_us-gaap_ProceedsFromIssuanceOfSharesUnderIncentiveAndShareBasedCompensationPlansIncludingStockOptionsAbstract_6C4617CBBC475F50BA030D84AA789B97" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Proceeds from Issuance of Shares under Incentive and Share-based Compensation Plans, Including Stock Options [Abstract]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ProceedsFromIssuanceOfSharesUnderIncentiveAndShareBasedCompensationPlansIncludingStockOptionsAbstract" xlink:label="loc_us-gaap_ProceedsFromIssuanceOfSharesUnderIncentiveAndShareBasedCompensationPlansIncludingStockOptionsAbstract_6C4617CBBC475F50BA030D84AA789B97" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ProceedsFromIssuanceOfSharesUnderIncentiveAndShareBasedCompensationPlansIncludingStockOptionsAbstract_6C4617CBBC475F50BA030D84AA789B97" xlink:to="lab_us-gaap_ProceedsFromIssuanceOfSharesUnderIncentiveAndShareBasedCompensationPlansIncludingStockOptionsAbstract_6C4617CBBC475F50BA030D84AA789B97" xlink:type="arc" />
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1_4D1D40FE632B893EC6FE0D84AA789CED_terseLabel_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1_4D1D40FE632B893EC6FE0D84AA789CED" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Stock options granted, vesting period</link:label>
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1_4D1D40FE632B893EC6FE0D84AA789CED_label_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1_4D1D40FE632B893EC6FE0D84AA789CED" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1_4D1D40FE632B893EC6FE0D84AA789CED" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1_4D1D40FE632B893EC6FE0D84AA789CED" xlink:to="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1_4D1D40FE632B893EC6FE0D84AA789CED" xlink:type="arc" />
    <link:label id="lab_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardExpirationPeriod_4D23A3E14C061E8E09730D84AA78262B_terseLabel_en-US" xlink:label="lab_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardExpirationPeriod_4D23A3E14C061E8E09730D84AA78262B" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Share-based compensation arrangement by share-based payment award, expiration period</link:label>
    <link:label id="lab_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardExpirationPeriod_4D23A3E14C061E8E09730D84AA78262B_label_en-US" xlink:label="lab_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardExpirationPeriod_4D23A3E14C061E8E09730D84AA78262B" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardExpirationPeriod" xlink:label="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardExpirationPeriod_4D23A3E14C061E8E09730D84AA78262B" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardExpirationPeriod_4D23A3E14C061E8E09730D84AA78262B" xlink:to="lab_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardExpirationPeriod_4D23A3E14C061E8E09730D84AA78262B" xlink:type="arc" />
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardRequisiteServicePeriod1_2CD519FCA18CF0B2D4880D84AA78063D_terseLabel_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardRequisiteServicePeriod1_2CD519FCA18CF0B2D4880D84AA78063D" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Stock options granted, contractual term</link:label>
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardRequisiteServicePeriod1_2CD519FCA18CF0B2D4880D84AA78063D_label_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardRequisiteServicePeriod1_2CD519FCA18CF0B2D4880D84AA78063D" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Share-based Compensation Arrangement by Share-based Payment Award, Award Requisite Service Period</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardRequisiteServicePeriod1" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardRequisiteServicePeriod1_2CD519FCA18CF0B2D4880D84AA78063D" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardRequisiteServicePeriod1_2CD519FCA18CF0B2D4880D84AA78063D" xlink:to="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardRequisiteServicePeriod1_2CD519FCA18CF0B2D4880D84AA78063D" xlink:type="arc" />
    <link:label id="lab_arnc_ShareBasedCompensationArrangementBySharebasedPaymentAwardAwardPerformancePeriod_A20FEDAF69FB6B7A57360D84AA78A676_terseLabel_en-US" xlink:label="lab_arnc_ShareBasedCompensationArrangementBySharebasedPaymentAwardAwardPerformancePeriod_A20FEDAF69FB6B7A57360D84AA78A676" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Share-based compensation arrangement by share-based payment award, award performance period</link:label>
    <link:label id="lab_arnc_ShareBasedCompensationArrangementBySharebasedPaymentAwardAwardPerformancePeriod_A20FEDAF69FB6B7A57360D84AA78A676_label_en-US" xlink:label="lab_arnc_ShareBasedCompensationArrangementBySharebasedPaymentAwardAwardPerformancePeriod_A20FEDAF69FB6B7A57360D84AA78A676" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Share-Based Compensation Arrangement By Share-based Payment Award, Award Performance Period</link:label>
    <link:label id="lab_arnc_ShareBasedCompensationArrangementBySharebasedPaymentAwardAwardPerformancePeriod_A20FEDAF69FB6B7A57360D84AA78A676_documentation_en-US" xlink:label="lab_arnc_ShareBasedCompensationArrangementBySharebasedPaymentAwardAwardPerformancePeriod_A20FEDAF69FB6B7A57360D84AA78A676" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Share-Based Compensation Arrangement By Share-based Payment Award, Award Performance Period</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_ShareBasedCompensationArrangementBySharebasedPaymentAwardAwardPerformancePeriod" xlink:label="loc_arnc_ShareBasedCompensationArrangementBySharebasedPaymentAwardAwardPerformancePeriod_A20FEDAF69FB6B7A57360D84AA78A676" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_ShareBasedCompensationArrangementBySharebasedPaymentAwardAwardPerformancePeriod_A20FEDAF69FB6B7A57360D84AA78A676" xlink:to="lab_arnc_ShareBasedCompensationArrangementBySharebasedPaymentAwardAwardPerformancePeriod_A20FEDAF69FB6B7A57360D84AA78A676" xlink:type="arc" />
    <link:label id="lab_us-gaap_ShareBasedCompensation_A94B6EF236C9178E427F0D84AA7874BD_terseLabel_en-US" xlink:label="lab_us-gaap_ShareBasedCompensation_A94B6EF236C9178E427F0D84AA7874BD" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Stock based compensation expense (benefit), before tax</link:label>
    <link:label id="lab_us-gaap_ShareBasedCompensation_A94B6EF236C9178E427F0D84AA7874BD_label_en-US" xlink:label="lab_us-gaap_ShareBasedCompensation_A94B6EF236C9178E427F0D84AA7874BD" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Share-based Compensation</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ShareBasedCompensation" xlink:label="loc_us-gaap_ShareBasedCompensation_A94B6EF236C9178E427F0D84AA7874BD" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ShareBasedCompensation_A94B6EF236C9178E427F0D84AA7874BD" xlink:to="lab_us-gaap_ShareBasedCompensation_A94B6EF236C9178E427F0D84AA7874BD" xlink:type="arc" />
    <link:label id="lab_us-gaap_AllocatedShareBasedCompensationExpenseNetOfTax_8784329924391FA6A2550D84AA780457_terseLabel_en-US" xlink:label="lab_us-gaap_AllocatedShareBasedCompensationExpenseNetOfTax_8784329924391FA6A2550D84AA780457" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Stock based compensation expense, after tax</link:label>
    <link:label id="lab_us-gaap_AllocatedShareBasedCompensationExpenseNetOfTax_8784329924391FA6A2550D84AA780457_label_en-US" xlink:label="lab_us-gaap_AllocatedShareBasedCompensationExpenseNetOfTax_8784329924391FA6A2550D84AA780457" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Allocated Share-based Compensation Expense, Net of Tax</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AllocatedShareBasedCompensationExpenseNetOfTax" xlink:label="loc_us-gaap_AllocatedShareBasedCompensationExpenseNetOfTax_8784329924391FA6A2550D84AA780457" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AllocatedShareBasedCompensationExpenseNetOfTax_8784329924391FA6A2550D84AA780457" xlink:to="lab_us-gaap_AllocatedShareBasedCompensationExpenseNetOfTax_8784329924391FA6A2550D84AA780457" xlink:type="arc" />
    <link:label id="lab_arnc_EstimatedPercentageOfCompensationExpenseInPerformanceBasedAwardPayouts_4DE93EDA2AAE2565E3460D84AA78AADC_terseLabel_en-US" xlink:label="lab_arnc_EstimatedPercentageOfCompensationExpenseInPerformanceBasedAwardPayouts_4DE93EDA2AAE2565E3460D84AA78AADC" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Stock based compensation expense, stock awards percentage</link:label>
    <link:label id="lab_arnc_EstimatedPercentageOfCompensationExpenseInPerformanceBasedAwardPayouts_4DE93EDA2AAE2565E3460D84AA78AADC_label_en-US" xlink:label="lab_arnc_EstimatedPercentageOfCompensationExpenseInPerformanceBasedAwardPayouts_4DE93EDA2AAE2565E3460D84AA78AADC" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Estimated Percentage Of Compensation Expense In Performance Based Award Payouts</link:label>
    <link:label id="lab_arnc_EstimatedPercentageOfCompensationExpenseInPerformanceBasedAwardPayouts_4DE93EDA2AAE2565E3460D84AA78AADC_documentation_en-US" xlink:label="lab_arnc_EstimatedPercentageOfCompensationExpenseInPerformanceBasedAwardPayouts_4DE93EDA2AAE2565E3460D84AA78AADC" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Estimated Percentage Of Compensation Expense In Performance Based Award Payouts</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_EstimatedPercentageOfCompensationExpenseInPerformanceBasedAwardPayouts" xlink:label="loc_arnc_EstimatedPercentageOfCompensationExpenseInPerformanceBasedAwardPayouts_4DE93EDA2AAE2565E3460D84AA78AADC" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_EstimatedPercentageOfCompensationExpenseInPerformanceBasedAwardPayouts_4DE93EDA2AAE2565E3460D84AA78AADC" xlink:to="lab_arnc_EstimatedPercentageOfCompensationExpenseInPerformanceBasedAwardPayouts_4DE93EDA2AAE2565E3460D84AA78AADC" xlink:type="arc" />
    <link:label id="lab_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized_79975104DF0089DFCBA40D84AA782885_terseLabel_en-US" xlink:label="lab_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized_79975104DF0089DFCBA40D84AA782885" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Unrecognized compensation costs on non-vested stock option awards (pretax)</link:label>
    <link:label id="lab_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized_79975104DF0089DFCBA40D84AA782885_label_en-US" xlink:label="lab_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized_79975104DF0089DFCBA40D84AA782885" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized" xlink:label="loc_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized_79975104DF0089DFCBA40D84AA782885" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized_79975104DF0089DFCBA40D84AA782885" xlink:to="lab_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized_79975104DF0089DFCBA40D84AA782885" xlink:type="arc" />
    <link:label id="lab_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedStockOptions_0FD62D8F6A060958602F0D84AA88567C_terseLabel_en-US" xlink:label="lab_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedStockOptions_0FD62D8F6A060958602F0D84AA88567C" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Unrecognized compensation costs on non-vested stock option grants (pretax)</link:label>
    <link:label id="lab_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedStockOptions_0FD62D8F6A060958602F0D84AA88567C_label_en-US" xlink:label="lab_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedStockOptions_0FD62D8F6A060958602F0D84AA88567C" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Employee Service Share-based Compensation, Nonvested Awards, Compensation Not yet Recognized, Stock Options</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedStockOptions" xlink:label="loc_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedStockOptions_0FD62D8F6A060958602F0D84AA88567C" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedStockOptions_0FD62D8F6A060958602F0D84AA88567C" xlink:to="lab_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedStockOptions_0FD62D8F6A060958602F0D84AA88567C" xlink:type="arc" />
    <link:label id="lab_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1_6BA8EABC657E048BD7340D84AA88D2C4_terseLabel_en-US" xlink:label="lab_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1_6BA8EABC657E048BD7340D84AA88D2C4" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Unrecognized compensation costs on non-vested awards, weighted average period of recognition in years</link:label>
    <link:label id="lab_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1_6BA8EABC657E048BD7340D84AA88D2C4_label_en-US" xlink:label="lab_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1_6BA8EABC657E048BD7340D84AA88D2C4" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1" xlink:label="loc_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1_6BA8EABC657E048BD7340D84AA88D2C4" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1_6BA8EABC657E048BD7340D84AA88D2C4" xlink:to="lab_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1_6BA8EABC657E048BD7340D84AA88D2C4" xlink:type="arc" />
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageGrantDateFairValue_601C41F1ACF9C628AAB20D84AA88F93D_terseLabel_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageGrantDateFairValue_601C41F1ACF9C628AAB20D84AA88F93D" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Share-based compensation arrangement by share-based payment award, options, grants in period, weighted average grant date fair value (in usd per share)</link:label>
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageGrantDateFairValue_601C41F1ACF9C628AAB20D84AA88F93D_label_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageGrantDateFairValue_601C41F1ACF9C628AAB20D84AA88F93D" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageGrantDateFairValue" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageGrantDateFairValue_601C41F1ACF9C628AAB20D84AA88F93D" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageGrantDateFairValue_601C41F1ACF9C628AAB20D84AA88F93D" xlink:to="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageGrantDateFairValue_601C41F1ACF9C628AAB20D84AA88F93D" xlink:type="arc" />
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRate_CD186ADF08705C33F8490D84AA886652_terseLabel_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRate_CD186ADF08705C33F8490D84AA886652" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Average risk-free interest rate. percentage</link:label>
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRate_CD186ADF08705C33F8490D84AA886652_label_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRate_CD186ADF08705C33F8490D84AA886652" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Risk Free Interest Rate</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRate" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRate_CD186ADF08705C33F8490D84AA886652" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRate_CD186ADF08705C33F8490D84AA886652" xlink:to="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRate_CD186ADF08705C33F8490D84AA886652" xlink:type="arc" />
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRate_A5FA43719093E83E1DAB0D84AA883EBD_terseLabel_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRate_A5FA43719093E83E1DAB0D84AA883EBD" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Volatility, percentage</link:label>
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRate_A5FA43719093E83E1DAB0D84AA883EBD_label_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRate_A5FA43719093E83E1DAB0D84AA883EBD" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Volatility Rate</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRate" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRate_A5FA43719093E83E1DAB0D84AA883EBD" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRate_A5FA43719093E83E1DAB0D84AA883EBD" xlink:to="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRate_A5FA43719093E83E1DAB0D84AA883EBD" xlink:type="arc" />
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedDividendRate_5D91CE56B4FE4C15A3100D84AA88A77D_terseLabel_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedDividendRate_5D91CE56B4FE4C15A3100D84AA88A77D" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Dividend yield, percentage</link:label>
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedDividendRate_5D91CE56B4FE4C15A3100D84AA88A77D_label_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedDividendRate_5D91CE56B4FE4C15A3100D84AA88A77D" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Dividend Rate</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedDividendRate" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedDividendRate_5D91CE56B4FE4C15A3100D84AA88A77D" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedDividendRate_5D91CE56B4FE4C15A3100D84AA88A77D" xlink:to="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedDividendRate_5D91CE56B4FE4C15A3100D84AA88A77D" xlink:type="arc" />
    <link:label id="lab_arnc_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsAnnualForfeitureRate_DE062FAB7D3FA67660450D84AA88EBEE_terseLabel_en-US" xlink:label="lab_arnc_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsAnnualForfeitureRate_DE062FAB7D3FA67660450D84AA88EBEE" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Annual pre- and post-vesting forfeitures, percentage</link:label>
    <link:label id="lab_arnc_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsAnnualForfeitureRate_DE062FAB7D3FA67660450D84AA88EBEE_label_en-US" xlink:label="lab_arnc_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsAnnualForfeitureRate_DE062FAB7D3FA67660450D84AA88EBEE" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions Annual Forfeiture Rate</link:label>
    <link:label id="lab_arnc_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsAnnualForfeitureRate_DE062FAB7D3FA67660450D84AA88EBEE_documentation_en-US" xlink:label="lab_arnc_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsAnnualForfeitureRate_DE062FAB7D3FA67660450D84AA88EBEE" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Share based compensation arrangement by share based payment award fair value assumptions annual forfeiture rate.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsAnnualForfeitureRate" xlink:label="loc_arnc_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsAnnualForfeitureRate_DE062FAB7D3FA67660450D84AA88EBEE" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsAnnualForfeitureRate_DE062FAB7D3FA67660450D84AA88EBEE" xlink:to="lab_arnc_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsAnnualForfeitureRate_DE062FAB7D3FA67660450D84AA88EBEE" xlink:type="arc" />
    <link:label id="lab_arnc_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExerciseBehavior_F10435A7FB6CD75B9CBF0D84AA885A86_terseLabel_en-US" xlink:label="lab_arnc_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExerciseBehavior_F10435A7FB6CD75B9CBF0D84AA885A86" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Exercise behavior, percentage</link:label>
    <link:label id="lab_arnc_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExerciseBehavior_F10435A7FB6CD75B9CBF0D84AA885A86_label_en-US" xlink:label="lab_arnc_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExerciseBehavior_F10435A7FB6CD75B9CBF0D84AA885A86" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions Exercise Behavior</link:label>
    <link:label id="lab_arnc_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExerciseBehavior_F10435A7FB6CD75B9CBF0D84AA885A86_documentation_en-US" xlink:label="lab_arnc_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExerciseBehavior_F10435A7FB6CD75B9CBF0D84AA885A86" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Share Based compensation arrangement by share based payment award fair value assumptions exercise behavior.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExerciseBehavior" xlink:label="loc_arnc_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExerciseBehavior_F10435A7FB6CD75B9CBF0D84AA885A86" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExerciseBehavior_F10435A7FB6CD75B9CBF0D84AA885A86" xlink:to="lab_arnc_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExerciseBehavior_F10435A7FB6CD75B9CBF0D84AA885A86" xlink:type="arc" />
    <link:label id="lab_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1_F573DD45C1E64905EF510D84AA8807CD_terseLabel_en-US" xlink:label="lab_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1_F573DD45C1E64905EF510D84AA8807CD" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Life (years)</link:label>
    <link:label id="lab_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1_F573DD45C1E64905EF510D84AA8807CD_label_en-US" xlink:label="lab_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1_F573DD45C1E64905EF510D84AA8807CD" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Term</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1" xlink:label="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1_F573DD45C1E64905EF510D84AA8807CD" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1_F573DD45C1E64905EF510D84AA8807CD" xlink:to="lab_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1_F573DD45C1E64905EF510D84AA8807CD" xlink:type="arc" />
    <link:label id="lab_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTerm2_A4E744163F35BB48BE680D84AA8876CE_terseLabel_en-US" xlink:label="lab_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTerm2_A4E744163F35BB48BE680D84AA8876CE" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Number of options, outstanding weighted average remaining contractual life</link:label>
    <link:label id="lab_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTerm2_A4E744163F35BB48BE680D84AA8876CE_label_en-US" xlink:label="lab_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTerm2_A4E744163F35BB48BE680D84AA8876CE" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Remaining Contractual Term</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTerm2" xlink:label="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTerm2_A4E744163F35BB48BE680D84AA8876CE" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTerm2_A4E744163F35BB48BE680D84AA8876CE" xlink:to="lab_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTerm2_A4E744163F35BB48BE680D84AA8876CE" xlink:type="arc" />
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValue_2257E3DE176041E3E2380D84AA88402B_terseLabel_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValue_2257E3DE176041E3E2380D84AA88402B" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Total intrinsic value of options outstanding</link:label>
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValue_2257E3DE176041E3E2380D84AA88402B_label_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValue_2257E3DE176041E3E2380D84AA88402B" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Intrinsic Value</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValue" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValue_2257E3DE176041E3E2380D84AA88402B" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValue_2257E3DE176041E3E2380D84AA88402B" xlink:to="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValue_2257E3DE176041E3E2380D84AA88402B" xlink:type="arc" />
    <link:label id="lab_arnc_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOptionsVestedInPeriod_BA4F69181EDD2401FAED0D84AA889C51_terseLabel_en-US" xlink:label="lab_arnc_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOptionsVestedInPeriod_BA4F69181EDD2401FAED0D84AA889C51" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Stock options vested (in shares)</link:label>
    <link:label id="lab_arnc_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOptionsVestedInPeriod_BA4F69181EDD2401FAED0D84AA889C51_label_en-US" xlink:label="lab_arnc_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOptionsVestedInPeriod_BA4F69181EDD2401FAED0D84AA889C51" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Options Vested In Period</link:label>
    <link:label id="lab_arnc_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOptionsVestedInPeriod_BA4F69181EDD2401FAED0D84AA889C51_documentation_en-US" xlink:label="lab_arnc_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOptionsVestedInPeriod_BA4F69181EDD2401FAED0D84AA889C51" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Options Vested In Period</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOptionsVestedInPeriod" xlink:label="loc_arnc_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOptionsVestedInPeriod_BA4F69181EDD2401FAED0D84AA889C51" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOptionsVestedInPeriod_BA4F69181EDD2401FAED0D84AA889C51" xlink:to="lab_arnc_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOptionsVestedInPeriod_BA4F69181EDD2401FAED0D84AA889C51" xlink:type="arc" />
    <link:label id="lab_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedAndExpectedToVestExercisableWeightedAverageRemainingContractualTerm1_E885BD4CCE0E6EAD4B890D84AA8835BC_terseLabel_en-US" xlink:label="lab_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedAndExpectedToVestExercisableWeightedAverageRemainingContractualTerm1_E885BD4CCE0E6EAD4B890D84AA8835BC" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Weighted average remaining contractual life, vested and exercisable</link:label>
    <link:label id="lab_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedAndExpectedToVestExercisableWeightedAverageRemainingContractualTerm1_E885BD4CCE0E6EAD4B890D84AA8835BC_label_en-US" xlink:label="lab_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedAndExpectedToVestExercisableWeightedAverageRemainingContractualTerm1_E885BD4CCE0E6EAD4B890D84AA8835BC" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Exercisable, Weighted Average Remaining Contractual Term</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedAndExpectedToVestExercisableWeightedAverageRemainingContractualTerm1" xlink:label="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedAndExpectedToVestExercisableWeightedAverageRemainingContractualTerm1_E885BD4CCE0E6EAD4B890D84AA8835BC" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedAndExpectedToVestExercisableWeightedAverageRemainingContractualTerm1_E885BD4CCE0E6EAD4B890D84AA8835BC" xlink:to="lab_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedAndExpectedToVestExercisableWeightedAverageRemainingContractualTerm1_E885BD4CCE0E6EAD4B890D84AA8835BC" xlink:type="arc" />
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestExercisableWeightedAverageExercisePrice_77E2DA2E2BB03E7C040D0D84AA881094_terseLabel_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestExercisableWeightedAverageExercisePrice_77E2DA2E2BB03E7C040D0D84AA881094" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Weighted average exercise price, vested and exercisable (in usd per share)</link:label>
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestExercisableWeightedAverageExercisePrice_77E2DA2E2BB03E7C040D0D84AA881094_label_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestExercisableWeightedAverageExercisePrice_77E2DA2E2BB03E7C040D0D84AA881094" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Exercisable, Weighted Average Exercise Price</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestExercisableWeightedAverageExercisePrice" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestExercisableWeightedAverageExercisePrice_77E2DA2E2BB03E7C040D0D84AA881094" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestExercisableWeightedAverageExercisePrice_77E2DA2E2BB03E7C040D0D84AA881094" xlink:to="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestExercisableWeightedAverageExercisePrice_77E2DA2E2BB03E7C040D0D84AA881094" xlink:type="arc" />
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestExercisableAggregateIntrinsicValue_79CDFB82537E994B03BD0D84AA888FB7_terseLabel_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestExercisableAggregateIntrinsicValue_79CDFB82537E994B03BD0D84AA888FB7" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Total intrinsic value of options vested and exercisable</link:label>
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestExercisableAggregateIntrinsicValue_79CDFB82537E994B03BD0D84AA888FB7_label_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestExercisableAggregateIntrinsicValue_79CDFB82537E994B03BD0D84AA888FB7" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Exercisable, Aggregate Intrinsic Value</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestExercisableAggregateIntrinsicValue" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestExercisableAggregateIntrinsicValue_79CDFB82537E994B03BD0D84AA888FB7" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestExercisableAggregateIntrinsicValue_79CDFB82537E994B03BD0D84AA888FB7" xlink:to="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestExercisableAggregateIntrinsicValue_79CDFB82537E994B03BD0D84AA888FB7" xlink:type="arc" />
    <link:label id="lab_us-gaap_ProceedsFromStockOptionsExercised_8556E3988A3864D8C4050D84AA88C256_terseLabel_en-US" xlink:label="lab_us-gaap_ProceedsFromStockOptionsExercised_8556E3988A3864D8C4050D84AA88C256" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Proceeds from exercise of employee stock options</link:label>
    <link:label id="lab_us-gaap_ProceedsFromStockOptionsExercised_8556E3988A3864D8C4050D84AA88C256_label_en-US" xlink:label="lab_us-gaap_ProceedsFromStockOptionsExercised_8556E3988A3864D8C4050D84AA88C256" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Proceeds from Stock Options Exercised</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ProceedsFromStockOptionsExercised" xlink:label="loc_us-gaap_ProceedsFromStockOptionsExercised_8556E3988A3864D8C4050D84AA88C256" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ProceedsFromStockOptionsExercised_8556E3988A3864D8C4050D84AA88C256" xlink:to="lab_us-gaap_ProceedsFromStockOptionsExercised_8556E3988A3864D8C4050D84AA88C256" xlink:type="arc" />
    <link:label id="lab_us-gaap_DeferredTaxExpenseFromStockOptionsExercised_619BE2542D336EF8456B0D84AA883861_terseLabel_en-US" xlink:label="lab_us-gaap_DeferredTaxExpenseFromStockOptionsExercised_619BE2542D336EF8456B0D84AA883861" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Total tax benefit realized from these exercises</link:label>
    <link:label id="lab_us-gaap_DeferredTaxExpenseFromStockOptionsExercised_619BE2542D336EF8456B0D84AA883861_label_en-US" xlink:label="lab_us-gaap_DeferredTaxExpenseFromStockOptionsExercised_619BE2542D336EF8456B0D84AA883861" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Deferred Tax Expense from Stock Options Exercised</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DeferredTaxExpenseFromStockOptionsExercised" xlink:label="loc_us-gaap_DeferredTaxExpenseFromStockOptionsExercised_619BE2542D336EF8456B0D84AA883861" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DeferredTaxExpenseFromStockOptionsExercised_619BE2542D336EF8456B0D84AA883861" xlink:to="lab_us-gaap_DeferredTaxExpenseFromStockOptionsExercised_619BE2542D336EF8456B0D84AA883861" xlink:type="arc" />
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisesInPeriodTotalIntrinsicValue_4BE39CEDC48DC2BACA0A0D84AA889E21_terseLabel_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisesInPeriodTotalIntrinsicValue_4BE39CEDC48DC2BACA0A0D84AA889E21" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Total intrinsic value of options exercised</link:label>
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisesInPeriodTotalIntrinsicValue_4BE39CEDC48DC2BACA0A0D84AA889E21_label_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisesInPeriodTotalIntrinsicValue_4BE39CEDC48DC2BACA0A0D84AA889E21" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Intrinsic Value</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisesInPeriodTotalIntrinsicValue" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisesInPeriodTotalIntrinsicValue_4BE39CEDC48DC2BACA0A0D84AA889E21" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisesInPeriodTotalIntrinsicValue_4BE39CEDC48DC2BACA0A0D84AA889E21" xlink:to="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisesInPeriodTotalIntrinsicValue_4BE39CEDC48DC2BACA0A0D84AA889E21" xlink:type="arc" />
    <link:label id="lab_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardAwardVestingRightsPercentage_D23AE2204B569F84B0E70D84AA8826FA_terseLabel_en-US" xlink:label="lab_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardAwardVestingRightsPercentage_D23AE2204B569F84B0E70D84AA8826FA" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Share-based compensation arrangement by share-based payment award, award vesting rights, percentage</link:label>
    <link:label id="lab_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardAwardVestingRightsPercentage_D23AE2204B569F84B0E70D84AA8826FA_label_en-US" xlink:label="lab_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardAwardVestingRightsPercentage_D23AE2204B569F84B0E70D84AA8826FA" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardAwardVestingRightsPercentage" xlink:label="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardAwardVestingRightsPercentage_D23AE2204B569F84B0E70D84AA8826FA" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardAwardVestingRightsPercentage_D23AE2204B569F84B0E70D84AA8826FA" xlink:to="lab_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardAwardVestingRightsPercentage_D23AE2204B569F84B0E70D84AA8826FA" xlink:type="arc" />
    <link:label id="lab_us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTable_F4CE52F7E1F5BBAD441C7C362DA12761_terseLabel_en-US" xlink:label="lab_us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTable_F4CE52F7E1F5BBAD441C7C362DA12761" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table]</link:label>
    <link:label id="lab_us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTable_F4CE52F7E1F5BBAD441C7C362DA12761_label_en-US" xlink:label="lab_us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTable_F4CE52F7E1F5BBAD441C7C362DA12761" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTable" xlink:label="loc_us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTable_F4CE52F7E1F5BBAD441C7C362DA12761" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTable_F4CE52F7E1F5BBAD441C7C362DA12761" xlink:to="lab_us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTable_F4CE52F7E1F5BBAD441C7C362DA12761" xlink:type="arc" />
    <link:label id="lab_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis_DC2A74F166A8FB5D7B0A7C362DA1CDA8_terseLabel_en-US" xlink:label="lab_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis_DC2A74F166A8FB5D7B0A7C362DA1CDA8" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Antidilutive Securities [Axis]</link:label>
    <link:label id="lab_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis_DC2A74F166A8FB5D7B0A7C362DA1CDA8_label_en-US" xlink:label="lab_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis_DC2A74F166A8FB5D7B0A7C362DA1CDA8" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Antidilutive Securities [Axis]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis" xlink:label="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis_DC2A74F166A8FB5D7B0A7C362DA1CDA8" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis_DC2A74F166A8FB5D7B0A7C362DA1CDA8" xlink:to="lab_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis_DC2A74F166A8FB5D7B0A7C362DA1CDA8" xlink:type="arc" />
    <link:label id="lab_us-gaap_AntidilutiveSecuritiesNameDomain_FE838DA3AA50A84D5F447C362DA1BDDB_terseLabel_en-US" xlink:label="lab_us-gaap_AntidilutiveSecuritiesNameDomain_FE838DA3AA50A84D5F447C362DA1BDDB" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Antidilutive Securities, Name [Domain]</link:label>
    <link:label id="lab_us-gaap_AntidilutiveSecuritiesNameDomain_FE838DA3AA50A84D5F447C362DA1BDDB_label_en-US" xlink:label="lab_us-gaap_AntidilutiveSecuritiesNameDomain_FE838DA3AA50A84D5F447C362DA1BDDB" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Antidilutive Securities, Name [Domain]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AntidilutiveSecuritiesNameDomain" xlink:label="loc_us-gaap_AntidilutiveSecuritiesNameDomain_FE838DA3AA50A84D5F447C362DA1BDDB" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AntidilutiveSecuritiesNameDomain_FE838DA3AA50A84D5F447C362DA1BDDB" xlink:to="lab_us-gaap_AntidilutiveSecuritiesNameDomain_FE838DA3AA50A84D5F447C362DA1BDDB" xlink:type="arc" />
    <link:label id="lab_arnc_MandatoryConvertibleNotesMember_132CC810204FF2AB979A7C362DA14C1D_terseLabel_en-US" xlink:label="lab_arnc_MandatoryConvertibleNotesMember_132CC810204FF2AB979A7C362DA14C1D" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Mandatory convertible preferred stock</link:label>
    <link:label id="lab_arnc_MandatoryConvertibleNotesMember_132CC810204FF2AB979A7C362DA14C1D_label_en-US" xlink:label="lab_arnc_MandatoryConvertibleNotesMember_132CC810204FF2AB979A7C362DA14C1D" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Mandatory Convertible Notes [Member]</link:label>
    <link:label id="lab_arnc_MandatoryConvertibleNotesMember_132CC810204FF2AB979A7C362DA14C1D_documentation_en-US" xlink:label="lab_arnc_MandatoryConvertibleNotesMember_132CC810204FF2AB979A7C362DA14C1D" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Mandatory Convertible Notes [Member]</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_MandatoryConvertibleNotesMember" xlink:label="loc_arnc_MandatoryConvertibleNotesMember_132CC810204FF2AB979A7C362DA14C1D" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_MandatoryConvertibleNotesMember_132CC810204FF2AB979A7C362DA14C1D" xlink:to="lab_arnc_MandatoryConvertibleNotesMember_132CC810204FF2AB979A7C362DA14C1D" xlink:type="arc" />
    <link:label id="lab_arnc_ConvertibleNotesMember_01143B00F3BA462E3E737C362DA1B7AC_terseLabel_en-US" xlink:label="lab_arnc_ConvertibleNotesMember_01143B00F3BA462E3E737C362DA1B7AC" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Convertible notes</link:label>
    <link:label id="lab_arnc_ConvertibleNotesMember_01143B00F3BA462E3E737C362DA1B7AC_label_en-US" xlink:label="lab_arnc_ConvertibleNotesMember_01143B00F3BA462E3E737C362DA1B7AC" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Convertible Notes [Member]</link:label>
    <link:label id="lab_arnc_ConvertibleNotesMember_01143B00F3BA462E3E737C362DA1B7AC_documentation_en-US" xlink:label="lab_arnc_ConvertibleNotesMember_01143B00F3BA462E3E737C362DA1B7AC" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Convertible notes.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_ConvertibleNotesMember" xlink:label="loc_arnc_ConvertibleNotesMember_01143B00F3BA462E3E737C362DA1B7AC" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_ConvertibleNotesMember_01143B00F3BA462E3E737C362DA1B7AC" xlink:to="lab_arnc_ConvertibleNotesMember_01143B00F3BA462E3E737C362DA1B7AC" xlink:type="arc" />
    <link:label id="lab_arnc_StockAwardsMember_AC5AAC91223E8B71BCFF7C362DA1E655_terseLabel_en-US" xlink:label="lab_arnc_StockAwardsMember_AC5AAC91223E8B71BCFF7C362DA1E655" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Stock awards</link:label>
    <link:label id="lab_arnc_StockAwardsMember_AC5AAC91223E8B71BCFF7C362DA1E655_label_en-US" xlink:label="lab_arnc_StockAwardsMember_AC5AAC91223E8B71BCFF7C362DA1E655" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Stock Awards [Member]</link:label>
    <link:label id="lab_arnc_StockAwardsMember_AC5AAC91223E8B71BCFF7C362DA1E655_documentation_en-US" xlink:label="lab_arnc_StockAwardsMember_AC5AAC91223E8B71BCFF7C362DA1E655" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Stock awards.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_StockAwardsMember" xlink:label="loc_arnc_StockAwardsMember_AC5AAC91223E8B71BCFF7C362DA1E655" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_StockAwardsMember_AC5AAC91223E8B71BCFF7C362DA1E655" xlink:to="lab_arnc_StockAwardsMember_AC5AAC91223E8B71BCFF7C362DA1E655" xlink:type="arc" />
    <link:label id="lab_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems_F654B605BAAE835329877C362DA16638_terseLabel_en-US" xlink:label="lab_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems_F654B605BAAE835329877C362DA16638" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]</link:label>
    <link:label id="lab_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems_F654B605BAAE835329877C362DA16638_label_en-US" xlink:label="lab_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems_F654B605BAAE835329877C362DA16638" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems" xlink:label="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems_F654B605BAAE835329877C362DA16638" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems_F654B605BAAE835329877C362DA16638" xlink:to="lab_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems_F654B605BAAE835329877C362DA16638" xlink:type="arc" />
    <link:label id="lab_arnc_SharesThatWouldHaveBeenIncludedInDilutedEarningsPerShareCalculation_9C4EDAC7A366A8CF56FB7C362DA1F607_terseLabel_en-US" xlink:label="lab_arnc_SharesThatWouldHaveBeenIncludedInDilutedEarningsPerShareCalculation_9C4EDAC7A366A8CF56FB7C362DA1F607" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Shares that would have been included in diluted earnings per share calculation (in shares)</link:label>
    <link:label id="lab_arnc_SharesThatWouldHaveBeenIncludedInDilutedEarningsPerShareCalculation_9C4EDAC7A366A8CF56FB7C362DA1F607_label_en-US" xlink:label="lab_arnc_SharesThatWouldHaveBeenIncludedInDilutedEarningsPerShareCalculation_9C4EDAC7A366A8CF56FB7C362DA1F607" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Shares That Would Have Been Included In Diluted Earnings Per Share Calculation</link:label>
    <link:label id="lab_arnc_SharesThatWouldHaveBeenIncludedInDilutedEarningsPerShareCalculation_9C4EDAC7A366A8CF56FB7C362DA1F607_documentation_en-US" xlink:label="lab_arnc_SharesThatWouldHaveBeenIncludedInDilutedEarningsPerShareCalculation_9C4EDAC7A366A8CF56FB7C362DA1F607" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Shares that would have been included in diluted earnings per share calculation.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_SharesThatWouldHaveBeenIncludedInDilutedEarningsPerShareCalculation" xlink:label="loc_arnc_SharesThatWouldHaveBeenIncludedInDilutedEarningsPerShareCalculation_9C4EDAC7A366A8CF56FB7C362DA1F607" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_SharesThatWouldHaveBeenIncludedInDilutedEarningsPerShareCalculation_9C4EDAC7A366A8CF56FB7C362DA1F607" xlink:to="lab_arnc_SharesThatWouldHaveBeenIncludedInDilutedEarningsPerShareCalculation_9C4EDAC7A366A8CF56FB7C362DA1F607" xlink:type="arc" />
    <link:label id="lab_us-gaap_DerivativeTable_681BDA6BE81F414FE730E244A956A924_terseLabel_en-US" xlink:label="lab_us-gaap_DerivativeTable_681BDA6BE81F414FE730E244A956A924" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Derivative [Table]</link:label>
    <link:label id="lab_us-gaap_DerivativeTable_681BDA6BE81F414FE730E244A956A924_label_en-US" xlink:label="lab_us-gaap_DerivativeTable_681BDA6BE81F414FE730E244A956A924" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Derivative [Table]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DerivativeTable" xlink:label="loc_us-gaap_DerivativeTable_681BDA6BE81F414FE730E244A956A924" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DerivativeTable_681BDA6BE81F414FE730E244A956A924" xlink:to="lab_us-gaap_DerivativeTable_681BDA6BE81F414FE730E244A956A924" xlink:type="arc" />
    <link:label id="lab_us-gaap_FairValueByMeasurementBasisAxis_6D547E05C54F388F78DDE244A956C918_terseLabel_en-US" xlink:label="lab_us-gaap_FairValueByMeasurementBasisAxis_6D547E05C54F388F78DDE244A956C918" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Measurement Basis [Axis]</link:label>
    <link:label id="lab_us-gaap_FairValueByMeasurementBasisAxis_6D547E05C54F388F78DDE244A956C918_label_en-US" xlink:label="lab_us-gaap_FairValueByMeasurementBasisAxis_6D547E05C54F388F78DDE244A956C918" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Measurement Basis [Axis]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_FairValueByMeasurementBasisAxis" xlink:label="loc_us-gaap_FairValueByMeasurementBasisAxis_6D547E05C54F388F78DDE244A956C918" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FairValueByMeasurementBasisAxis_6D547E05C54F388F78DDE244A956C918" xlink:to="lab_us-gaap_FairValueByMeasurementBasisAxis_6D547E05C54F388F78DDE244A956C918" xlink:type="arc" />
    <link:label id="lab_us-gaap_FairValueDisclosureItemAmountsDomain_B5B5B5F380D3BD2377FFE244A95A6F2B_terseLabel_en-US" xlink:label="lab_us-gaap_FairValueDisclosureItemAmountsDomain_B5B5B5F380D3BD2377FFE244A95A6F2B" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Fair Value Measurement [Domain]</link:label>
    <link:label id="lab_us-gaap_FairValueDisclosureItemAmountsDomain_B5B5B5F380D3BD2377FFE244A95A6F2B_label_en-US" xlink:label="lab_us-gaap_FairValueDisclosureItemAmountsDomain_B5B5B5F380D3BD2377FFE244A95A6F2B" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Fair Value Measurement [Domain]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_FairValueDisclosureItemAmountsDomain" xlink:label="loc_us-gaap_FairValueDisclosureItemAmountsDomain_B5B5B5F380D3BD2377FFE244A95A6F2B" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FairValueDisclosureItemAmountsDomain_B5B5B5F380D3BD2377FFE244A95A6F2B" xlink:to="lab_us-gaap_FairValueDisclosureItemAmountsDomain_B5B5B5F380D3BD2377FFE244A95A6F2B" xlink:type="arc" />
    <link:label id="lab_us-gaap_PortionAtFairValueFairValueDisclosureMember_E623E9662A6F47F2576AE244A95ACE48_terseLabel_en-US" xlink:label="lab_us-gaap_PortionAtFairValueFairValueDisclosureMember_E623E9662A6F47F2576AE244A95ACE48" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Portion at Fair Value Measurement [Member]</link:label>
    <link:label id="lab_us-gaap_PortionAtFairValueFairValueDisclosureMember_E623E9662A6F47F2576AE244A95ACE48_label_en-US" xlink:label="lab_us-gaap_PortionAtFairValueFairValueDisclosureMember_E623E9662A6F47F2576AE244A95ACE48" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Portion at Fair Value Measurement [Member]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PortionAtFairValueFairValueDisclosureMember" xlink:label="loc_us-gaap_PortionAtFairValueFairValueDisclosureMember_E623E9662A6F47F2576AE244A95ACE48" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PortionAtFairValueFairValueDisclosureMember_E623E9662A6F47F2576AE244A95ACE48" xlink:to="lab_us-gaap_PortionAtFairValueFairValueDisclosureMember_E623E9662A6F47F2576AE244A95ACE48" xlink:type="arc" />
    <link:label id="lab_us-gaap_CarryingReportedAmountFairValueDisclosureMember_2F82384CBF63ED13C8C6E244A95AB943_terseLabel_en-US" xlink:label="lab_us-gaap_CarryingReportedAmountFairValueDisclosureMember_2F82384CBF63ED13C8C6E244A95AB943" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Carrying value</link:label>
    <link:label id="lab_us-gaap_CarryingReportedAmountFairValueDisclosureMember_2F82384CBF63ED13C8C6E244A95AB943_label_en-US" xlink:label="lab_us-gaap_CarryingReportedAmountFairValueDisclosureMember_2F82384CBF63ED13C8C6E244A95AB943" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Reported Value Measurement [Member]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_CarryingReportedAmountFairValueDisclosureMember" xlink:label="loc_us-gaap_CarryingReportedAmountFairValueDisclosureMember_2F82384CBF63ED13C8C6E244A95AB943" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CarryingReportedAmountFairValueDisclosureMember_2F82384CBF63ED13C8C6E244A95AB943" xlink:to="lab_us-gaap_CarryingReportedAmountFairValueDisclosureMember_2F82384CBF63ED13C8C6E244A95AB943" xlink:type="arc" />
    <link:label id="lab_us-gaap_EstimateOfFairValueFairValueDisclosureMember_F6277A77032842942763E244A95A13E3_terseLabel_en-US" xlink:label="lab_us-gaap_EstimateOfFairValueFairValueDisclosureMember_F6277A77032842942763E244A95A13E3" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Fair value</link:label>
    <link:label id="lab_us-gaap_EstimateOfFairValueFairValueDisclosureMember_F6277A77032842942763E244A95A13E3_label_en-US" xlink:label="lab_us-gaap_EstimateOfFairValueFairValueDisclosureMember_F6277A77032842942763E244A95A13E3" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Estimate of Fair Value Measurement [Member]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_EstimateOfFairValueFairValueDisclosureMember" xlink:label="loc_us-gaap_EstimateOfFairValueFairValueDisclosureMember_F6277A77032842942763E244A95A13E3" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_EstimateOfFairValueFairValueDisclosureMember_F6277A77032842942763E244A95A13E3" xlink:to="lab_us-gaap_EstimateOfFairValueFairValueDisclosureMember_F6277A77032842942763E244A95A13E3" xlink:type="arc" />
    <link:label id="lab_us-gaap_DerivativeLineItems_30B1D041029B14A52B39E244A95AC1AC_terseLabel_en-US" xlink:label="lab_us-gaap_DerivativeLineItems_30B1D041029B14A52B39E244A95AC1AC" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Derivative [Line Items]</link:label>
    <link:label id="lab_us-gaap_DerivativeLineItems_30B1D041029B14A52B39E244A95AC1AC_label_en-US" xlink:label="lab_us-gaap_DerivativeLineItems_30B1D041029B14A52B39E244A95AC1AC" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Derivative [Line Items]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DerivativeLineItems" xlink:label="loc_us-gaap_DerivativeLineItems_30B1D041029B14A52B39E244A95AC1AC" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DerivativeLineItems_30B1D041029B14A52B39E244A95AC1AC" xlink:to="lab_us-gaap_DerivativeLineItems_30B1D041029B14A52B39E244A95AC1AC" xlink:type="arc" />
    <link:label id="lab_us-gaap_LongTermDebtFairValue_EB85538CFDB9A9946CB7E244A95AAD2A_terseLabel_en-US" xlink:label="lab_us-gaap_LongTermDebtFairValue_EB85538CFDB9A9946CB7E244A95AAD2A" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Long-term debt, less amount due within one year</link:label>
    <link:label id="lab_us-gaap_LongTermDebtFairValue_EB85538CFDB9A9946CB7E244A95AAD2A_label_en-US" xlink:label="lab_us-gaap_LongTermDebtFairValue_EB85538CFDB9A9946CB7E244A95AAD2A" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Long-term Debt, Fair Value</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_LongTermDebtFairValue" xlink:label="loc_us-gaap_LongTermDebtFairValue_EB85538CFDB9A9946CB7E244A95AAD2A" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LongTermDebtFairValue_EB85538CFDB9A9946CB7E244A95AAD2A" xlink:to="lab_us-gaap_LongTermDebtFairValue_EB85538CFDB9A9946CB7E244A95AAD2A" xlink:type="arc" />
    <link:label id="lab_us-gaap_TransfersAndServicingAbstract_6FDC639A503A3BB64C3002565F77EA9E_label_en-US" xlink:label="lab_us-gaap_TransfersAndServicingAbstract_6FDC639A503A3BB64C3002565F77EA9E" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Transfers and Servicing [Abstract]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_TransfersAndServicingAbstract" xlink:label="loc_us-gaap_TransfersAndServicingAbstract_6FDC639A503A3BB64C3002565F77EA9E" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_TransfersAndServicingAbstract_6FDC639A503A3BB64C3002565F77EA9E" xlink:to="lab_us-gaap_TransfersAndServicingAbstract_6FDC639A503A3BB64C3002565F77EA9E" xlink:type="arc" />
    <link:label id="lab_arnc_ScheduleOfFinancialReceivablesTable_7E137A22D55DF758D89F02565F773819_terseLabel_en-US" xlink:label="lab_arnc_ScheduleOfFinancialReceivablesTable_7E137A22D55DF758D89F02565F773819" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Schedule Of Financial Receivables [Table]</link:label>
    <link:label id="lab_arnc_ScheduleOfFinancialReceivablesTable_7E137A22D55DF758D89F02565F773819_label_en-US" xlink:label="lab_arnc_ScheduleOfFinancialReceivablesTable_7E137A22D55DF758D89F02565F773819" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Schedule Of Financial Receivables [Table]</link:label>
    <link:label id="lab_arnc_ScheduleOfFinancialReceivablesTable_7E137A22D55DF758D89F02565F773819_documentation_en-US" xlink:label="lab_arnc_ScheduleOfFinancialReceivablesTable_7E137A22D55DF758D89F02565F773819" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Schedule Of Financial Receivables [Table]</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_ScheduleOfFinancialReceivablesTable" xlink:label="loc_arnc_ScheduleOfFinancialReceivablesTable_7E137A22D55DF758D89F02565F773819" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_ScheduleOfFinancialReceivablesTable_7E137A22D55DF758D89F02565F773819" xlink:to="lab_arnc_ScheduleOfFinancialReceivablesTable_7E137A22D55DF758D89F02565F773819" xlink:type="arc" />
    <link:label id="lab_arnc_ScheduleOfFinancialReceivablesLineItems_BDD1202AFD43E86F302402565F77D36F_terseLabel_en-US" xlink:label="lab_arnc_ScheduleOfFinancialReceivablesLineItems_BDD1202AFD43E86F302402565F77D36F" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Schedule Of Financial Receivables [Line Items]</link:label>
    <link:label id="lab_arnc_ScheduleOfFinancialReceivablesLineItems_BDD1202AFD43E86F302402565F77D36F_label_en-US" xlink:label="lab_arnc_ScheduleOfFinancialReceivablesLineItems_BDD1202AFD43E86F302402565F77D36F" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Schedule Of Financial Receivables [Line Items]</link:label>
    <link:label id="lab_arnc_ScheduleOfFinancialReceivablesLineItems_BDD1202AFD43E86F302402565F77D36F_documentation_en-US" xlink:label="lab_arnc_ScheduleOfFinancialReceivablesLineItems_BDD1202AFD43E86F302402565F77D36F" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Schedule Of Financial Receivables [Line Items]</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_ScheduleOfFinancialReceivablesLineItems" xlink:label="loc_arnc_ScheduleOfFinancialReceivablesLineItems_BDD1202AFD43E86F302402565F77D36F" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_ScheduleOfFinancialReceivablesLineItems_BDD1202AFD43E86F302402565F77D36F" xlink:to="lab_arnc_ScheduleOfFinancialReceivablesLineItems_BDD1202AFD43E86F302402565F77D36F" xlink:type="arc" />
    <link:label id="lab_arnc_NumberOfArrangementsToSellCustomerReceivables_E6638F4B97A9223184F302565F77F8D2_terseLabel_en-US" xlink:label="lab_arnc_NumberOfArrangementsToSellCustomerReceivables_E6638F4B97A9223184F302565F77F8D2" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Number of arrangement with different financial institution to sell customer receivables</link:label>
    <link:label id="lab_arnc_NumberOfArrangementsToSellCustomerReceivables_E6638F4B97A9223184F302565F77F8D2_label_en-US" xlink:label="lab_arnc_NumberOfArrangementsToSellCustomerReceivables_E6638F4B97A9223184F302565F77F8D2" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Number Of Arrangements To Sell Customer Receivables</link:label>
    <link:label id="lab_arnc_NumberOfArrangementsToSellCustomerReceivables_E6638F4B97A9223184F302565F77F8D2_documentation_en-US" xlink:label="lab_arnc_NumberOfArrangementsToSellCustomerReceivables_E6638F4B97A9223184F302565F77F8D2" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Number of arrangements to sell customer receivables.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_NumberOfArrangementsToSellCustomerReceivables" xlink:label="loc_arnc_NumberOfArrangementsToSellCustomerReceivables_E6638F4B97A9223184F302565F77F8D2" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_NumberOfArrangementsToSellCustomerReceivables_E6638F4B97A9223184F302565F77F8D2" xlink:to="lab_arnc_NumberOfArrangementsToSellCustomerReceivables_E6638F4B97A9223184F302565F77F8D2" xlink:type="arc" />
    <link:label id="lab_arnc_FundingOfCustomerReceivablesSold_A569B635C3F11C0BEDEE02565F77CF0D_terseLabel_en-US" xlink:label="lab_arnc_FundingOfCustomerReceivablesSold_A569B635C3F11C0BEDEE02565F77CF0D" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Funding of customer receivables sold</link:label>
    <link:label id="lab_arnc_FundingOfCustomerReceivablesSold_A569B635C3F11C0BEDEE02565F77CF0D_label_en-US" xlink:label="lab_arnc_FundingOfCustomerReceivablesSold_A569B635C3F11C0BEDEE02565F77CF0D" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Funding Of Customer Receivables Sold</link:label>
    <link:label id="lab_arnc_FundingOfCustomerReceivablesSold_A569B635C3F11C0BEDEE02565F77CF0D_documentation_en-US" xlink:label="lab_arnc_FundingOfCustomerReceivablesSold_A569B635C3F11C0BEDEE02565F77CF0D" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Funding of customer receivables sold.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_FundingOfCustomerReceivablesSold" xlink:label="loc_arnc_FundingOfCustomerReceivablesSold_A569B635C3F11C0BEDEE02565F77CF0D" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_FundingOfCustomerReceivablesSold_A569B635C3F11C0BEDEE02565F77CF0D" xlink:to="lab_arnc_FundingOfCustomerReceivablesSold_A569B635C3F11C0BEDEE02565F77CF0D" xlink:type="arc" />
    <link:label id="lab_arnc_SaleOfCustomerReceivables_18CF4389FAB2192EC2F002565F7795D3_terseLabel_en-US" xlink:label="lab_arnc_SaleOfCustomerReceivables_18CF4389FAB2192EC2F002565F7795D3" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Sale of customer receivables</link:label>
    <link:label id="lab_arnc_SaleOfCustomerReceivables_18CF4389FAB2192EC2F002565F7795D3_label_en-US" xlink:label="lab_arnc_SaleOfCustomerReceivables_18CF4389FAB2192EC2F002565F7795D3" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Sale Of Customer Receivables</link:label>
    <link:label id="lab_arnc_SaleOfCustomerReceivables_18CF4389FAB2192EC2F002565F7795D3_documentation_en-US" xlink:label="lab_arnc_SaleOfCustomerReceivables_18CF4389FAB2192EC2F002565F7795D3" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Sale of customer receivables</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_SaleOfCustomerReceivables" xlink:label="loc_arnc_SaleOfCustomerReceivables_18CF4389FAB2192EC2F002565F7795D3" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_SaleOfCustomerReceivables_18CF4389FAB2192EC2F002565F7795D3" xlink:to="lab_arnc_SaleOfCustomerReceivables_18CF4389FAB2192EC2F002565F7795D3" xlink:type="arc" />
    <link:label id="lab_us-gaap_ProceedsFromSaleOfFinanceReceivables_79E2340A14E1DBDCB3F802565F7743C8_verboseLabel_en-US" xlink:label="lab_us-gaap_ProceedsFromSaleOfFinanceReceivables_79E2340A14E1DBDCB3F802565F7743C8" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Cash received for receivables</link:label>
    <link:label id="lab_us-gaap_ProceedsFromSaleOfFinanceReceivables_79E2340A14E1DBDCB3F802565F7743C8_label_en-US" xlink:label="lab_us-gaap_ProceedsFromSaleOfFinanceReceivables_79E2340A14E1DBDCB3F802565F7743C8" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Proceeds from Sale of Finance Receivables</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ProceedsFromSaleOfFinanceReceivables" xlink:label="loc_us-gaap_ProceedsFromSaleOfFinanceReceivables_79E2340A14E1DBDCB3F802565F7743C8" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ProceedsFromSaleOfFinanceReceivables_79E2340A14E1DBDCB3F802565F7743C8" xlink:to="lab_us-gaap_ProceedsFromSaleOfFinanceReceivables_79E2340A14E1DBDCB3F802565F7743C8" xlink:type="arc" />
    <link:label id="lab_arnc_DeferredPriceCustomerReceivables_F10C99C87E134E0C2A3E02565F77C4E7_terseLabel_en-US" xlink:label="lab_arnc_DeferredPriceCustomerReceivables_F10C99C87E134E0C2A3E02565F77C4E7" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Deferred purchase price receivable</link:label>
    <link:label id="lab_arnc_DeferredPriceCustomerReceivables_F10C99C87E134E0C2A3E02565F77C4E7_label_en-US" xlink:label="lab_arnc_DeferredPriceCustomerReceivables_F10C99C87E134E0C2A3E02565F77C4E7" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Deferred Price Customer Receivables</link:label>
    <link:label id="lab_arnc_DeferredPriceCustomerReceivables_F10C99C87E134E0C2A3E02565F77C4E7_documentation_en-US" xlink:label="lab_arnc_DeferredPriceCustomerReceivables_F10C99C87E134E0C2A3E02565F77C4E7" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Deferred purchase price customer receivables.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_DeferredPriceCustomerReceivables" xlink:label="loc_arnc_DeferredPriceCustomerReceivables_F10C99C87E134E0C2A3E02565F77C4E7" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_DeferredPriceCustomerReceivables_F10C99C87E134E0C2A3E02565F77C4E7" xlink:to="lab_arnc_DeferredPriceCustomerReceivables_F10C99C87E134E0C2A3E02565F77C4E7" xlink:type="arc" />
    <link:label id="lab_arnc_NetCashFundingReceivedForDevelopmentOfReservesDuringThePeriod_7D85618A4D70A77CDCB202565F77F746_terseLabel_en-US" xlink:label="lab_arnc_NetCashFundingReceivedForDevelopmentOfReservesDuringThePeriod_7D85618A4D70A77CDCB202565F77F746" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Net cash funding received during the period</link:label>
    <link:label id="lab_arnc_NetCashFundingReceivedForDevelopmentOfReservesDuringThePeriod_7D85618A4D70A77CDCB202565F77F746_label_en-US" xlink:label="lab_arnc_NetCashFundingReceivedForDevelopmentOfReservesDuringThePeriod_7D85618A4D70A77CDCB202565F77F746" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Net Cash Funding Received For Development Of Reserves During The Period</link:label>
    <link:label id="lab_arnc_NetCashFundingReceivedForDevelopmentOfReservesDuringThePeriod_7D85618A4D70A77CDCB202565F77F746_documentation_en-US" xlink:label="lab_arnc_NetCashFundingReceivedForDevelopmentOfReservesDuringThePeriod_7D85618A4D70A77CDCB202565F77F746" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Net cash funding received for development of reserves during the period.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_NetCashFundingReceivedForDevelopmentOfReservesDuringThePeriod" xlink:label="loc_arnc_NetCashFundingReceivedForDevelopmentOfReservesDuringThePeriod_7D85618A4D70A77CDCB202565F77F746" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_NetCashFundingReceivedForDevelopmentOfReservesDuringThePeriod_7D85618A4D70A77CDCB202565F77F746" xlink:to="lab_arnc_NetCashFundingReceivedForDevelopmentOfReservesDuringThePeriod_7D85618A4D70A77CDCB202565F77F746" xlink:type="arc" />
    <link:label id="lab_arnc_ProceedsFromReceivableFundingDuringThePeriod_9A60C21BAC814A15AD1C02565F77D3BE_terseLabel_en-US" xlink:label="lab_arnc_ProceedsFromReceivableFundingDuringThePeriod_9A60C21BAC814A15AD1C02565F77D3BE" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Amount of cash draws under arrangement during the period</link:label>
    <link:label id="lab_arnc_ProceedsFromReceivableFundingDuringThePeriod_9A60C21BAC814A15AD1C02565F77D3BE_label_en-US" xlink:label="lab_arnc_ProceedsFromReceivableFundingDuringThePeriod_9A60C21BAC814A15AD1C02565F77D3BE" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Proceeds From Receivable Funding During The Period</link:label>
    <link:label id="lab_arnc_ProceedsFromReceivableFundingDuringThePeriod_9A60C21BAC814A15AD1C02565F77D3BE_documentation_en-US" xlink:label="lab_arnc_ProceedsFromReceivableFundingDuringThePeriod_9A60C21BAC814A15AD1C02565F77D3BE" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Proceeds from receivable funding during the period.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_ProceedsFromReceivableFundingDuringThePeriod" xlink:label="loc_arnc_ProceedsFromReceivableFundingDuringThePeriod_9A60C21BAC814A15AD1C02565F77D3BE" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_ProceedsFromReceivableFundingDuringThePeriod_9A60C21BAC814A15AD1C02565F77D3BE" xlink:to="lab_arnc_ProceedsFromReceivableFundingDuringThePeriod_9A60C21BAC814A15AD1C02565F77D3BE" xlink:type="arc" />
    <link:label id="lab_arnc_RepaymentsForReceivableFundingDuringThePeriod_92537293E54716E367DD02565F7740E1_negatedTerseLabel_en-US" xlink:label="lab_arnc_RepaymentsForReceivableFundingDuringThePeriod_92537293E54716E367DD02565F7740E1" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:type="resource" xml:lang="en-US">Amount of cash repayments under arrangement during the period</link:label>
    <link:label id="lab_arnc_RepaymentsForReceivableFundingDuringThePeriod_92537293E54716E367DD02565F7740E1_label_en-US" xlink:label="lab_arnc_RepaymentsForReceivableFundingDuringThePeriod_92537293E54716E367DD02565F7740E1" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Repayments For Receivable Funding During The Period</link:label>
    <link:label id="lab_arnc_RepaymentsForReceivableFundingDuringThePeriod_92537293E54716E367DD02565F7740E1_documentation_en-US" xlink:label="lab_arnc_RepaymentsForReceivableFundingDuringThePeriod_92537293E54716E367DD02565F7740E1" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Repayments for receivable funding during the period.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_RepaymentsForReceivableFundingDuringThePeriod" xlink:label="loc_arnc_RepaymentsForReceivableFundingDuringThePeriod_92537293E54716E367DD02565F7740E1" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_RepaymentsForReceivableFundingDuringThePeriod_92537293E54716E367DD02565F7740E1" xlink:to="lab_arnc_RepaymentsForReceivableFundingDuringThePeriod_92537293E54716E367DD02565F7740E1" xlink:type="arc" />
    <link:label id="lab_arnc_ProceedsFromReceivableFundingSinceInception_DA73A41B8238F0D4542302565F77CB9D_terseLabel_en-US" xlink:label="lab_arnc_ProceedsFromReceivableFundingSinceInception_DA73A41B8238F0D4542302565F77CB9D" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Amount of cash draws under arrangement since inception</link:label>
    <link:label id="lab_arnc_ProceedsFromReceivableFundingSinceInception_DA73A41B8238F0D4542302565F77CB9D_label_en-US" xlink:label="lab_arnc_ProceedsFromReceivableFundingSinceInception_DA73A41B8238F0D4542302565F77CB9D" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Proceeds From Receivable Funding Since Inception</link:label>
    <link:label id="lab_arnc_ProceedsFromReceivableFundingSinceInception_DA73A41B8238F0D4542302565F77CB9D_documentation_en-US" xlink:label="lab_arnc_ProceedsFromReceivableFundingSinceInception_DA73A41B8238F0D4542302565F77CB9D" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Proceeds from receivable funding since inception.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_ProceedsFromReceivableFundingSinceInception" xlink:label="loc_arnc_ProceedsFromReceivableFundingSinceInception_DA73A41B8238F0D4542302565F77CB9D" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_ProceedsFromReceivableFundingSinceInception_DA73A41B8238F0D4542302565F77CB9D" xlink:to="lab_arnc_ProceedsFromReceivableFundingSinceInception_DA73A41B8238F0D4542302565F77CB9D" xlink:type="arc" />
    <link:label id="lab_arnc_RepaymentsForReceivableFundingSinceInception_26C569482093F22748F602565F773573_negatedTerseLabel_en-US" xlink:label="lab_arnc_RepaymentsForReceivableFundingSinceInception_26C569482093F22748F602565F773573" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:type="resource" xml:lang="en-US">Amount of cash repayments under arrangement since inception</link:label>
    <link:label id="lab_arnc_RepaymentsForReceivableFundingSinceInception_26C569482093F22748F602565F773573_label_en-US" xlink:label="lab_arnc_RepaymentsForReceivableFundingSinceInception_26C569482093F22748F602565F773573" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Repayments For Receivable Funding Since Inception</link:label>
    <link:label id="lab_arnc_RepaymentsForReceivableFundingSinceInception_26C569482093F22748F602565F773573_documentation_en-US" xlink:label="lab_arnc_RepaymentsForReceivableFundingSinceInception_26C569482093F22748F602565F773573" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Repayments for receivable funding since inception.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_RepaymentsForReceivableFundingSinceInception" xlink:label="loc_arnc_RepaymentsForReceivableFundingSinceInception_26C569482093F22748F602565F773573" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_RepaymentsForReceivableFundingSinceInception_26C569482093F22748F602565F773573" xlink:to="lab_arnc_RepaymentsForReceivableFundingSinceInception_26C569482093F22748F602565F773573" xlink:type="arc" />
    <link:label id="lab_arnc_GrossAmountofReceivablesSoldSinceInception_085CB33BA470FE7C9FCB02565F77372D_terseLabel_en-US" xlink:label="lab_arnc_GrossAmountofReceivablesSoldSinceInception_085CB33BA470FE7C9FCB02565F77372D" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Gross amount of receivables sold under the deferred purchase program</link:label>
    <link:label id="lab_arnc_GrossAmountofReceivablesSoldSinceInception_085CB33BA470FE7C9FCB02565F77372D_label_en-US" xlink:label="lab_arnc_GrossAmountofReceivablesSoldSinceInception_085CB33BA470FE7C9FCB02565F77372D" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Gross Amount of Receivables Sold Since Inception</link:label>
    <link:label id="lab_arnc_GrossAmountofReceivablesSoldSinceInception_085CB33BA470FE7C9FCB02565F77372D_documentation_en-US" xlink:label="lab_arnc_GrossAmountofReceivablesSoldSinceInception_085CB33BA470FE7C9FCB02565F77372D" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Gross Amount of Receivables Sold Since Inception</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_GrossAmountofReceivablesSoldSinceInception" xlink:label="loc_arnc_GrossAmountofReceivablesSoldSinceInception_085CB33BA470FE7C9FCB02565F77372D" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_GrossAmountofReceivablesSoldSinceInception_085CB33BA470FE7C9FCB02565F77372D" xlink:to="lab_arnc_GrossAmountofReceivablesSoldSinceInception_085CB33BA470FE7C9FCB02565F77372D" xlink:type="arc" />
    <link:label id="lab_us-gaap_ProceedsFromCollectionOfOtherReceivables_53774FB9380049CFAF4702565F770720_terseLabel_en-US" xlink:label="lab_us-gaap_ProceedsFromCollectionOfOtherReceivables_53774FB9380049CFAF4702565F770720" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Cash collections of other receivables</link:label>
    <link:label id="lab_us-gaap_ProceedsFromCollectionOfOtherReceivables_53774FB9380049CFAF4702565F770720_label_en-US" xlink:label="lab_us-gaap_ProceedsFromCollectionOfOtherReceivables_53774FB9380049CFAF4702565F770720" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Proceeds from Collection of Other Receivables</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ProceedsFromCollectionOfOtherReceivables" xlink:label="loc_us-gaap_ProceedsFromCollectionOfOtherReceivables_53774FB9380049CFAF4702565F770720" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ProceedsFromCollectionOfOtherReceivables_53774FB9380049CFAF4702565F770720" xlink:to="lab_us-gaap_ProceedsFromCollectionOfOtherReceivables_53774FB9380049CFAF4702565F770720" xlink:type="arc" />
    <link:label id="lab_arnc_CashOutflowInflowFromDeferredPurchaseReceivable_48C6E2CC5DD119BBF69402565F77666A_terseLabel_en-US" xlink:label="lab_arnc_CashOutflowInflowFromDeferredPurchaseReceivable_48C6E2CC5DD119BBF69402565F77666A" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Gross cash outflows from deferred purchased receivables</link:label>
    <link:label id="lab_arnc_CashOutflowInflowFromDeferredPurchaseReceivable_48C6E2CC5DD119BBF69402565F77666A_label_en-US" xlink:label="lab_arnc_CashOutflowInflowFromDeferredPurchaseReceivable_48C6E2CC5DD119BBF69402565F77666A" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Cash Outflow (Inflow) From Deferred Purchase Receivable</link:label>
    <link:label id="lab_arnc_CashOutflowInflowFromDeferredPurchaseReceivable_48C6E2CC5DD119BBF69402565F77666A_documentation_en-US" xlink:label="lab_arnc_CashOutflowInflowFromDeferredPurchaseReceivable_48C6E2CC5DD119BBF69402565F77666A" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Cash Outflow (Inflow) From Deferred Purchase Receivable</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_CashOutflowInflowFromDeferredPurchaseReceivable" xlink:label="loc_arnc_CashOutflowInflowFromDeferredPurchaseReceivable_48C6E2CC5DD119BBF69402565F77666A" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_CashOutflowInflowFromDeferredPurchaseReceivable_48C6E2CC5DD119BBF69402565F77666A" xlink:to="lab_arnc_CashOutflowInflowFromDeferredPurchaseReceivable_48C6E2CC5DD119BBF69402565F77666A" xlink:type="arc" />
    <link:label id="lab_arnc_CashInflowOutflowFromDeferredPurchaseReceivable_136BC2555018F6D1542802565F77863A_terseLabel_en-US" xlink:label="lab_arnc_CashInflowOutflowFromDeferredPurchaseReceivable_136BC2555018F6D1542802565F77863A" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Gross cash inflow from deferred purchase receivable</link:label>
    <link:label id="lab_arnc_CashInflowOutflowFromDeferredPurchaseReceivable_136BC2555018F6D1542802565F77863A_label_en-US" xlink:label="lab_arnc_CashInflowOutflowFromDeferredPurchaseReceivable_136BC2555018F6D1542802565F77863A" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Cash Inflow (Outflow) From Deferred Purchase Receivable</link:label>
    <link:label id="lab_arnc_CashInflowOutflowFromDeferredPurchaseReceivable_136BC2555018F6D1542802565F77863A_documentation_en-US" xlink:label="lab_arnc_CashInflowOutflowFromDeferredPurchaseReceivable_136BC2555018F6D1542802565F77863A" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Cash Inflow (Outflow) From Deferred Purchase Receivable</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_CashInflowOutflowFromDeferredPurchaseReceivable" xlink:label="loc_arnc_CashInflowOutflowFromDeferredPurchaseReceivable_136BC2555018F6D1542802565F77863A" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_CashInflowOutflowFromDeferredPurchaseReceivable_136BC2555018F6D1542802565F77863A" xlink:to="lab_arnc_CashInflowOutflowFromDeferredPurchaseReceivable_136BC2555018F6D1542802565F77863A" xlink:type="arc" />
    <link:label id="lab_us-gaap_DefinedBenefitPlanEffectOfOnePercentagePointIncreaseOnAccumulatedPostretirementBenefitObligation_FFE7FA72E89D5D15DC80F19FAE258B16_terseLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanEffectOfOnePercentagePointIncreaseOnAccumulatedPostretirementBenefitObligation_FFE7FA72E89D5D15DC80F19FAE258B16" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Effect of 1% increase on other postretirement benefit obligations</link:label>
    <link:label id="lab_us-gaap_DefinedBenefitPlanEffectOfOnePercentagePointIncreaseOnAccumulatedPostretirementBenefitObligation_FFE7FA72E89D5D15DC80F19FAE258B16_label_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanEffectOfOnePercentagePointIncreaseOnAccumulatedPostretirementBenefitObligation_FFE7FA72E89D5D15DC80F19FAE258B16" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Effect of One Percentage Point Increase on Accumulated Postretirement Benefit Obligation</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DefinedBenefitPlanEffectOfOnePercentagePointIncreaseOnAccumulatedPostretirementBenefitObligation" xlink:label="loc_us-gaap_DefinedBenefitPlanEffectOfOnePercentagePointIncreaseOnAccumulatedPostretirementBenefitObligation_FFE7FA72E89D5D15DC80F19FAE258B16" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanEffectOfOnePercentagePointIncreaseOnAccumulatedPostretirementBenefitObligation_FFE7FA72E89D5D15DC80F19FAE258B16" xlink:to="lab_us-gaap_DefinedBenefitPlanEffectOfOnePercentagePointIncreaseOnAccumulatedPostretirementBenefitObligation_FFE7FA72E89D5D15DC80F19FAE258B16" xlink:type="arc" />
    <link:label id="lab_us-gaap_DefinedBenefitPlanEffectOfOnePercentagePointDecreaseOnAccumulatedPostretirementBenefitObligation1_0460154C4385BBBB1828F19FAE258412_negatedTerseLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanEffectOfOnePercentagePointDecreaseOnAccumulatedPostretirementBenefitObligation1_0460154C4385BBBB1828F19FAE258412" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:type="resource" xml:lang="en-US">Effect of 1% decrease on other postretirement benefit obligation</link:label>
    <link:label id="lab_us-gaap_DefinedBenefitPlanEffectOfOnePercentagePointDecreaseOnAccumulatedPostretirementBenefitObligation1_0460154C4385BBBB1828F19FAE258412_label_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanEffectOfOnePercentagePointDecreaseOnAccumulatedPostretirementBenefitObligation1_0460154C4385BBBB1828F19FAE258412" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Effect of One Percentage Point Decrease on Accumulated Postretirement Benefit Obligation</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DefinedBenefitPlanEffectOfOnePercentagePointDecreaseOnAccumulatedPostretirementBenefitObligation1" xlink:label="loc_us-gaap_DefinedBenefitPlanEffectOfOnePercentagePointDecreaseOnAccumulatedPostretirementBenefitObligation1_0460154C4385BBBB1828F19FAE258412" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanEffectOfOnePercentagePointDecreaseOnAccumulatedPostretirementBenefitObligation1_0460154C4385BBBB1828F19FAE258412" xlink:to="lab_us-gaap_DefinedBenefitPlanEffectOfOnePercentagePointDecreaseOnAccumulatedPostretirementBenefitObligation1_0460154C4385BBBB1828F19FAE258412" xlink:type="arc" />
    <link:label id="lab_us-gaap_DefinedBenefitPlanEffectOfOnePercentagePointIncreaseOnServiceAndInterestCostComponents_496A65C6E9F8D0BB69CDF19FAE25BEBB_terseLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanEffectOfOnePercentagePointIncreaseOnServiceAndInterestCostComponents_496A65C6E9F8D0BB69CDF19FAE25BEBB" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Effect of 1% increase on total of service and interest cost components</link:label>
    <link:label id="lab_us-gaap_DefinedBenefitPlanEffectOfOnePercentagePointIncreaseOnServiceAndInterestCostComponents_496A65C6E9F8D0BB69CDF19FAE25BEBB_label_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanEffectOfOnePercentagePointIncreaseOnServiceAndInterestCostComponents_496A65C6E9F8D0BB69CDF19FAE25BEBB" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Effect of One Percentage Point Increase on Service and Interest Cost Components</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DefinedBenefitPlanEffectOfOnePercentagePointIncreaseOnServiceAndInterestCostComponents" xlink:label="loc_us-gaap_DefinedBenefitPlanEffectOfOnePercentagePointIncreaseOnServiceAndInterestCostComponents_496A65C6E9F8D0BB69CDF19FAE25BEBB" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanEffectOfOnePercentagePointIncreaseOnServiceAndInterestCostComponents_496A65C6E9F8D0BB69CDF19FAE25BEBB" xlink:to="lab_us-gaap_DefinedBenefitPlanEffectOfOnePercentagePointIncreaseOnServiceAndInterestCostComponents_496A65C6E9F8D0BB69CDF19FAE25BEBB" xlink:type="arc" />
    <link:label id="lab_us-gaap_DefinedBenefitPlanEffectOfOnePercentagePointDecreaseOnServiceAndInterestCostComponents1_91DDD72252CF0443C636F19FAE26F114_negatedTerseLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanEffectOfOnePercentagePointDecreaseOnServiceAndInterestCostComponents1_91DDD72252CF0443C636F19FAE26F114" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:type="resource" xml:lang="en-US">Effect of 1% decrease on total of service and interest cost components</link:label>
    <link:label id="lab_us-gaap_DefinedBenefitPlanEffectOfOnePercentagePointDecreaseOnServiceAndInterestCostComponents1_91DDD72252CF0443C636F19FAE26F114_label_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanEffectOfOnePercentagePointDecreaseOnServiceAndInterestCostComponents1_91DDD72252CF0443C636F19FAE26F114" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Effect of One Percentage Point Decrease on Service and Interest Cost Components</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DefinedBenefitPlanEffectOfOnePercentagePointDecreaseOnServiceAndInterestCostComponents1" xlink:label="loc_us-gaap_DefinedBenefitPlanEffectOfOnePercentagePointDecreaseOnServiceAndInterestCostComponents1_91DDD72252CF0443C636F19FAE26F114" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanEffectOfOnePercentagePointDecreaseOnServiceAndInterestCostComponents1_91DDD72252CF0443C636F19FAE26F114" xlink:to="lab_us-gaap_DefinedBenefitPlanEffectOfOnePercentagePointDecreaseOnServiceAndInterestCostComponents1_91DDD72252CF0443C636F19FAE26F114" xlink:type="arc" />
    <link:label id="lab_us-gaap_MachineryAndEquipmentMember_8972DC00B02C6DE7AE0095CE5EDFA9BD_terseLabel_en-US" xlink:label="lab_us-gaap_MachineryAndEquipmentMember_8972DC00B02C6DE7AE0095CE5EDFA9BD" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Machinery and equipment</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_MachineryAndEquipmentMember" xlink:label="loc_us-gaap_MachineryAndEquipmentMember_8972DC00B02C6DE7AE0095CE5EDFA9BD" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_MachineryAndEquipmentMember_8972DC00B02C6DE7AE0095CE5EDFA9BD" xlink:to="lab_us-gaap_MachineryAndEquipmentMember_8972DC00B02C6DE7AE0095CE5EDFA9BD" xlink:type="arc" />
    <link:label id="lab_arnc_EngineeredProductsAndSolutionsMember_A13A127D4E21CFB9D0F895CE5EDF9C11_verboseLabel_en-US" xlink:label="lab_arnc_EngineeredProductsAndSolutionsMember_A13A127D4E21CFB9D0F895CE5EDF9C11" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Engineered Products and Solutions</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_EngineeredProductsAndSolutionsMember" xlink:label="loc_arnc_EngineeredProductsAndSolutionsMember_A13A127D4E21CFB9D0F895CE5EDF9C11" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_EngineeredProductsAndSolutionsMember_A13A127D4E21CFB9D0F895CE5EDF9C11" xlink:to="lab_arnc_EngineeredProductsAndSolutionsMember_A13A127D4E21CFB9D0F895CE5EDF9C11" xlink:type="arc" />
    <link:label id="lab_us-gaap_PropertyPlantAndEquipmentUsefulLife_0F8472303584A9E8388A95CE5EE33667_terseLabel_en-US" xlink:label="lab_us-gaap_PropertyPlantAndEquipmentUsefulLife_0F8472303584A9E8388A95CE5EE33667" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Weighted-average useful lives of assets, years</link:label>
    <link:label id="lab_us-gaap_PropertyPlantAndEquipmentUsefulLife_0F8472303584A9E8388A95CE5EE33667_label_en-US" xlink:label="lab_us-gaap_PropertyPlantAndEquipmentUsefulLife_0F8472303584A9E8388A95CE5EE33667" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Property, Plant and Equipment, Useful Life</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PropertyPlantAndEquipmentUsefulLife" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentUsefulLife_0F8472303584A9E8388A95CE5EE33667" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentUsefulLife_0F8472303584A9E8388A95CE5EE33667" xlink:to="lab_us-gaap_PropertyPlantAndEquipmentUsefulLife_0F8472303584A9E8388A95CE5EE33667" xlink:type="arc" />
    <link:label id="lab_us-gaap_InterestExpense_B51A3129330301567716C96832A8E71B_totalLabel_en-US" xlink:label="lab_us-gaap_InterestExpense_B51A3129330301567716C96832A8E71B" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Amount charged to expense</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_InterestExpense" xlink:label="loc_us-gaap_InterestExpense_B51A3129330301567716C96832A8E71B" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_InterestExpense_B51A3129330301567716C96832A8E71B" xlink:to="lab_us-gaap_InterestExpense_B51A3129330301567716C96832A8E71B" xlink:type="arc" />
    <link:label id="lab_us-gaap_InterestCostsCapitalizedAdjustment_64874AAA38C40B4733D5C9685A496B7D_terseLabel_en-US" xlink:label="lab_us-gaap_InterestCostsCapitalizedAdjustment_64874AAA38C40B4733D5C9685A496B7D" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Amount capitalized</link:label>
    <link:label id="lab_us-gaap_InterestCostsCapitalizedAdjustment_64874AAA38C40B4733D5C9685A496B7D_label_en-US" xlink:label="lab_us-gaap_InterestCostsCapitalizedAdjustment_64874AAA38C40B4733D5C9685A496B7D" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Interest Costs Capitalized Adjustment</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_InterestCostsCapitalizedAdjustment" xlink:label="loc_us-gaap_InterestCostsCapitalizedAdjustment_64874AAA38C40B4733D5C9685A496B7D" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_InterestCostsCapitalizedAdjustment_64874AAA38C40B4733D5C9685A496B7D" xlink:to="lab_us-gaap_InterestCostsCapitalizedAdjustment_64874AAA38C40B4733D5C9685A496B7D" xlink:type="arc" />
    <link:label id="lab_us-gaap_InterestCostsIncurred_E7067DD1E6FC7C1BEB3AC96832A9E858_terseLabel_en-US" xlink:label="lab_us-gaap_InterestCostsIncurred_E7067DD1E6FC7C1BEB3AC96832A9E858" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Interest costs</link:label>
    <link:label id="lab_us-gaap_InterestCostsIncurred_E7067DD1E6FC7C1BEB3AC96832A9E858_label_en-US" xlink:label="lab_us-gaap_InterestCostsIncurred_E7067DD1E6FC7C1BEB3AC96832A9E858" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Interest Costs Incurred</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_InterestCostsIncurred" xlink:label="loc_us-gaap_InterestCostsIncurred_E7067DD1E6FC7C1BEB3AC96832A9E858" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_InterestCostsIncurred_E7067DD1E6FC7C1BEB3AC96832A9E858" xlink:to="lab_us-gaap_InterestCostsIncurred_E7067DD1E6FC7C1BEB3AC96832A9E858" xlink:type="arc" />
    <link:label id="lab_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_BAF2712FC75071EFE3CBC968BD138437_terseLabel_en-US" xlink:label="lab_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_BAF2712FC75071EFE3CBC968BD138437" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table]</link:label>
    <link:label id="lab_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_BAF2712FC75071EFE3CBC968BD138437_label_en-US" xlink:label="lab_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_BAF2712FC75071EFE3CBC968BD138437" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable" xlink:label="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_BAF2712FC75071EFE3CBC968BD138437" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_BAF2712FC75071EFE3CBC968BD138437" xlink:to="lab_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_BAF2712FC75071EFE3CBC968BD138437" xlink:type="arc" />
    <link:label id="lab_us-gaap_TreasuryStockMember_45A90D5E33895EF5E99AC968BD1409C0_terseLabel_en-US" xlink:label="lab_us-gaap_TreasuryStockMember_45A90D5E33895EF5E99AC968BD1409C0" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Treasury stock</link:label>
    <link:label id="lab_us-gaap_TreasuryStockMember_45A90D5E33895EF5E99AC968BD1409C0_label_en-US" xlink:label="lab_us-gaap_TreasuryStockMember_45A90D5E33895EF5E99AC968BD1409C0" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Treasury Stock [Member]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_TreasuryStockMember" xlink:label="loc_us-gaap_TreasuryStockMember_45A90D5E33895EF5E99AC968BD1409C0" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_TreasuryStockMember_45A90D5E33895EF5E99AC968BD1409C0" xlink:to="lab_us-gaap_TreasuryStockMember_45A90D5E33895EF5E99AC968BD1409C0" xlink:type="arc" />
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_BBA36A83F269D487C970C968BD15475B_terseLabel_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_BBA36A83F269D487C970C968BD15475B" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Share-based Compensation Arrangement by Share-based Payment Award [Line Items]</link:label>
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_BBA36A83F269D487C970C968BD15475B_label_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_BBA36A83F269D487C970C968BD15475B" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Share-based Compensation Arrangement by Share-based Payment Award [Line Items]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_BBA36A83F269D487C970C968BD15475B" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_BBA36A83F269D487C970C968BD15475B" xlink:to="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_BBA36A83F269D487C970C968BD15475B" xlink:type="arc" />
    <link:label id="lab_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_092F476FB95C3CFC4F70C968BD15EAAB_terseLabel_en-US" xlink:label="lab_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_092F476FB95C3CFC4F70C968BD15EAAB" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Increase (Decrease) in Stockholders' Equity [Roll Forward]</link:label>
    <link:label id="lab_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_092F476FB95C3CFC4F70C968BD15EAAB_label_en-US" xlink:label="lab_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_092F476FB95C3CFC4F70C968BD15EAAB" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Increase (Decrease) in Stockholders' Equity [Roll Forward]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_IncreaseDecreaseInStockholdersEquityRollForward" xlink:label="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_092F476FB95C3CFC4F70C968BD15EAAB" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_092F476FB95C3CFC4F70C968BD15EAAB" xlink:to="lab_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_092F476FB95C3CFC4F70C968BD15EAAB" xlink:type="arc" />
    <link:label id="lab_us-gaap_TreasuryStockShares_87C2315FD7B4FB24FF33C968BD153336_periodStartLabel_en-US" xlink:label="lab_us-gaap_TreasuryStockShares_87C2315FD7B4FB24FF33C968BD153336" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel" xlink:type="resource" xml:lang="en-US">Treasury stock, beginning balance (in shares)</link:label>
    <link:label id="lab_us-gaap_TreasuryStockShares_87C2315FD7B4FB24FF33C968BD153336_label_en-US" xlink:label="lab_us-gaap_TreasuryStockShares_87C2315FD7B4FB24FF33C968BD153336" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Treasury Stock, Shares</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_TreasuryStockShares" xlink:label="loc_us-gaap_TreasuryStockShares_87C2315FD7B4FB24FF33C968BD153336" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_TreasuryStockShares_87C2315FD7B4FB24FF33C968BD153336" xlink:to="lab_us-gaap_TreasuryStockShares_87C2315FD7B4FB24FF33C968BD153336" xlink:type="arc" />
    <link:label id="lab_us-gaap_CommonStockSharesOutstanding_EF241FAE11E4572664CCC968BD1521EA_periodStartLabel_en-US" xlink:label="lab_us-gaap_CommonStockSharesOutstanding_EF241FAE11E4572664CCC968BD1521EA" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel" xlink:type="resource" xml:lang="en-US">Common stock outstanding, beginning balance (in shares)</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_CommonStockSharesOutstanding" xlink:label="loc_us-gaap_CommonStockSharesOutstanding_EF241FAE11E4572664CCC968BD1521EA" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CommonStockSharesOutstanding_EF241FAE11E4572664CCC968BD1521EA" xlink:to="lab_us-gaap_CommonStockSharesOutstanding_EF241FAE11E4572664CCC968BD1521EA" xlink:type="arc" />
    <link:label id="lab_us-gaap_StockIssuedDuringPeriodSharesShareBasedCompensation_336343B4176512FA6D37C968BD15DF46_negatedTerseLabel_en-US" xlink:label="lab_us-gaap_StockIssuedDuringPeriodSharesShareBasedCompensation_336343B4176512FA6D37C968BD15DF46" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:type="resource" xml:lang="en-US">Issued for stock-based compensation plans (in shares)</link:label>
    <link:label id="lab_us-gaap_StockIssuedDuringPeriodSharesShareBasedCompensation_336343B4176512FA6D37C968BD15DF46_label_en-US" xlink:label="lab_us-gaap_StockIssuedDuringPeriodSharesShareBasedCompensation_336343B4176512FA6D37C968BD15DF46" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Stock Issued During Period, Shares, Share-based Compensation, Net of Forfeitures</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_StockIssuedDuringPeriodSharesShareBasedCompensation" xlink:label="loc_us-gaap_StockIssuedDuringPeriodSharesShareBasedCompensation_336343B4176512FA6D37C968BD15DF46" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_StockIssuedDuringPeriodSharesShareBasedCompensation_336343B4176512FA6D37C968BD15DF46" xlink:to="lab_us-gaap_StockIssuedDuringPeriodSharesShareBasedCompensation_336343B4176512FA6D37C968BD15DF46" xlink:type="arc" />
    <link:label id="lab_us-gaap_TreasuryStockSharesRetired_F80D2E0AC2CBE7E635A4C968BD166CBE_negatedLabel_en-US" xlink:label="lab_us-gaap_TreasuryStockSharesRetired_F80D2E0AC2CBE7E635A4C968BD166CBE" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xml:lang="en-US">Treasury stock retirement (in shares)</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_TreasuryStockSharesRetired" xlink:label="loc_us-gaap_TreasuryStockSharesRetired_F80D2E0AC2CBE7E635A4C968BD166CBE" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_TreasuryStockSharesRetired_F80D2E0AC2CBE7E635A4C968BD166CBE" xlink:to="lab_us-gaap_TreasuryStockSharesRetired_F80D2E0AC2CBE7E635A4C968BD166CBE" xlink:type="arc" />
    <link:label id="lab_us-gaap_StockIssuedDuringPeriodSharesReverseStockSplits_B211B264D5436306961CC968BD168576_negatedLabel_en-US" xlink:label="lab_us-gaap_StockIssuedDuringPeriodSharesReverseStockSplits_B211B264D5436306961CC968BD168576" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xml:lang="en-US">Reverse stock split (in shares)</link:label>
    <link:label id="lab_us-gaap_StockIssuedDuringPeriodSharesReverseStockSplits_B211B264D5436306961CC968BD168576_label_en-US" xlink:label="lab_us-gaap_StockIssuedDuringPeriodSharesReverseStockSplits_B211B264D5436306961CC968BD168576" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Stock Issued During Period, Shares, Reverse Stock Splits</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_StockIssuedDuringPeriodSharesReverseStockSplits" xlink:label="loc_us-gaap_StockIssuedDuringPeriodSharesReverseStockSplits_B211B264D5436306961CC968BD168576" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_StockIssuedDuringPeriodSharesReverseStockSplits_B211B264D5436306961CC968BD168576" xlink:to="lab_us-gaap_StockIssuedDuringPeriodSharesReverseStockSplits_B211B264D5436306961CC968BD168576" xlink:type="arc" />
    <link:label id="lab_us-gaap_StockIssuedDuringPeriodSharesConversionOfConvertibleSecurities_07516146368F3A48623CC968BD16999A_terseLabel_en-US" xlink:label="lab_us-gaap_StockIssuedDuringPeriodSharesConversionOfConvertibleSecurities_07516146368F3A48623CC968BD16999A" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Conversion of convertible notes (in shares)</link:label>
    <link:label id="lab_us-gaap_StockIssuedDuringPeriodSharesConversionOfConvertibleSecurities_07516146368F3A48623CC968BD16999A_label_en-US" xlink:label="lab_us-gaap_StockIssuedDuringPeriodSharesConversionOfConvertibleSecurities_07516146368F3A48623CC968BD16999A" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Stock Issued During Period, Shares, Conversion of Convertible Securities</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_StockIssuedDuringPeriodSharesConversionOfConvertibleSecurities" xlink:label="loc_us-gaap_StockIssuedDuringPeriodSharesConversionOfConvertibleSecurities_07516146368F3A48623CC968BD16999A" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_StockIssuedDuringPeriodSharesConversionOfConvertibleSecurities_07516146368F3A48623CC968BD16999A" xlink:to="lab_us-gaap_StockIssuedDuringPeriodSharesConversionOfConvertibleSecurities_07516146368F3A48623CC968BD16999A" xlink:type="arc" />
    <link:label id="lab_us-gaap_TreasuryStockShares_8F297E4BDD2AE3BBFA34C968BD1683D4_periodEndLabel_en-US" xlink:label="lab_us-gaap_TreasuryStockShares_8F297E4BDD2AE3BBFA34C968BD1683D4" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel" xlink:type="resource" xml:lang="en-US">Treasury stock, ending balance (in shares)</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_TreasuryStockShares" xlink:label="loc_us-gaap_TreasuryStockShares_8F297E4BDD2AE3BBFA34C968BD1683D4" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_TreasuryStockShares_8F297E4BDD2AE3BBFA34C968BD1683D4" xlink:to="lab_us-gaap_TreasuryStockShares_8F297E4BDD2AE3BBFA34C968BD1683D4" xlink:type="arc" />
    <link:label id="lab_us-gaap_CommonStockSharesOutstanding_39B25279E094F203B716C968BD173FC0_periodEndLabel_en-US" xlink:label="lab_us-gaap_CommonStockSharesOutstanding_39B25279E094F203B716C968BD173FC0" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel" xlink:type="resource" xml:lang="en-US">Common stock outstanding, ending balance (in shares)</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_CommonStockSharesOutstanding" xlink:label="loc_us-gaap_CommonStockSharesOutstanding_39B25279E094F203B716C968BD173FC0" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CommonStockSharesOutstanding_39B25279E094F203B716C968BD173FC0" xlink:to="lab_us-gaap_CommonStockSharesOutstanding_39B25279E094F203B716C968BD173FC0" xlink:type="arc" />
    <link:label id="lab_us-gaap_ScheduleOfEarningsPerShareBasicAndDilutedTableTextBlock_6021CACBCC8360257F7D7C362DB1041A_terseLabel_en-US" xlink:label="lab_us-gaap_ScheduleOfEarningsPerShareBasicAndDilutedTableTextBlock_6021CACBCC8360257F7D7C362DB1041A" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Reconciliation of Information Used to Compute Basic and Diluted EPS</link:label>
    <link:label id="lab_us-gaap_ScheduleOfEarningsPerShareBasicAndDilutedTableTextBlock_6021CACBCC8360257F7D7C362DB1041A_label_en-US" xlink:label="lab_us-gaap_ScheduleOfEarningsPerShareBasicAndDilutedTableTextBlock_6021CACBCC8360257F7D7C362DB1041A" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Schedule of Earnings Per Share, Basic and Diluted [Table Text Block]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ScheduleOfEarningsPerShareBasicAndDilutedTableTextBlock" xlink:label="loc_us-gaap_ScheduleOfEarningsPerShareBasicAndDilutedTableTextBlock_6021CACBCC8360257F7D7C362DB1041A" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfEarningsPerShareBasicAndDilutedTableTextBlock_6021CACBCC8360257F7D7C362DB1041A" xlink:to="lab_us-gaap_ScheduleOfEarningsPerShareBasicAndDilutedTableTextBlock_6021CACBCC8360257F7D7C362DB1041A" xlink:type="arc" />
    <link:label id="lab_us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTextBlock_BB9B03DB259A4E4B7A917C362DB1DB4C_terseLabel_en-US" xlink:label="lab_us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTextBlock_BB9B03DB259A4E4B7A917C362DB1DB4C" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share</link:label>
    <link:label id="lab_us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTextBlock_BB9B03DB259A4E4B7A917C362DB1DB4C_label_en-US" xlink:label="lab_us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTextBlock_BB9B03DB259A4E4B7A917C362DB1DB4C" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table Text Block]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTextBlock" xlink:label="loc_us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTextBlock_BB9B03DB259A4E4B7A917C362DB1DB4C" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTextBlock_BB9B03DB259A4E4B7A917C362DB1DB4C" xlink:to="lab_us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTextBlock_BB9B03DB259A4E4B7A917C362DB1DB4C" xlink:type="arc" />
    <link:label id="lab_arnc_ScheduleOfOtherNonOperatingIncomeExpenseTable_4BF793E6530037089A09EDFC595C418A_terseLabel_en-US" xlink:label="lab_arnc_ScheduleOfOtherNonOperatingIncomeExpenseTable_4BF793E6530037089A09EDFC595C418A" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Schedule Of Other Non operating Income Expense [Table]</link:label>
    <link:label id="lab_arnc_ScheduleOfOtherNonOperatingIncomeExpenseTable_4BF793E6530037089A09EDFC595C418A_label_en-US" xlink:label="lab_arnc_ScheduleOfOtherNonOperatingIncomeExpenseTable_4BF793E6530037089A09EDFC595C418A" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Schedule Of Other Non operating Income Expense [Table]</link:label>
    <link:label id="lab_arnc_ScheduleOfOtherNonOperatingIncomeExpenseTable_4BF793E6530037089A09EDFC595C418A_documentation_en-US" xlink:label="lab_arnc_ScheduleOfOtherNonOperatingIncomeExpenseTable_4BF793E6530037089A09EDFC595C418A" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Schedule Of Other Non operating Income Expense [Table]</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_ScheduleOfOtherNonOperatingIncomeExpenseTable" xlink:label="loc_arnc_ScheduleOfOtherNonOperatingIncomeExpenseTable_4BF793E6530037089A09EDFC595C418A" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_ScheduleOfOtherNonOperatingIncomeExpenseTable_4BF793E6530037089A09EDFC595C418A" xlink:to="lab_arnc_ScheduleOfOtherNonOperatingIncomeExpenseTable_4BF793E6530037089A09EDFC595C418A" xlink:type="arc" />
    <link:label id="lab_us-gaap_OtherNonoperatingIncomeExpenseMember_693A2FC06518D7FFD767EDFC595D73B3_terseLabel_en-US" xlink:label="lab_us-gaap_OtherNonoperatingIncomeExpenseMember_693A2FC06518D7FFD767EDFC595D73B3" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Other Nonoperating Income (Expense)</link:label>
    <link:label id="lab_us-gaap_OtherNonoperatingIncomeExpenseMember_693A2FC06518D7FFD767EDFC595D73B3_label_en-US" xlink:label="lab_us-gaap_OtherNonoperatingIncomeExpenseMember_693A2FC06518D7FFD767EDFC595D73B3" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Other Nonoperating Income (Expense) [Member]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_OtherNonoperatingIncomeExpenseMember" xlink:label="loc_us-gaap_OtherNonoperatingIncomeExpenseMember_693A2FC06518D7FFD767EDFC595D73B3" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OtherNonoperatingIncomeExpenseMember_693A2FC06518D7FFD767EDFC595D73B3" xlink:to="lab_us-gaap_OtherNonoperatingIncomeExpenseMember_693A2FC06518D7FFD767EDFC595D73B3" xlink:type="arc" />
    <link:label id="lab_arnc_OtherNonOperatingIncomeExpenseLineItems_9916D7AAE113E7D82619EDFC59601B13_terseLabel_en-US" xlink:label="lab_arnc_OtherNonOperatingIncomeExpenseLineItems_9916D7AAE113E7D82619EDFC59601B13" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Other Non operating Income Expense [Line Items]</link:label>
    <link:label id="lab_arnc_OtherNonOperatingIncomeExpenseLineItems_9916D7AAE113E7D82619EDFC59601B13_label_en-US" xlink:label="lab_arnc_OtherNonOperatingIncomeExpenseLineItems_9916D7AAE113E7D82619EDFC59601B13" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Other Non operating Income Expense [Line Items]</link:label>
    <link:label id="lab_arnc_OtherNonOperatingIncomeExpenseLineItems_9916D7AAE113E7D82619EDFC59601B13_documentation_en-US" xlink:label="lab_arnc_OtherNonOperatingIncomeExpenseLineItems_9916D7AAE113E7D82619EDFC59601B13" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Other Non operating Income Expense [Line Items]</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_OtherNonOperatingIncomeExpenseLineItems" xlink:label="loc_arnc_OtherNonOperatingIncomeExpenseLineItems_9916D7AAE113E7D82619EDFC59601B13" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_OtherNonOperatingIncomeExpenseLineItems_9916D7AAE113E7D82619EDFC59601B13" xlink:to="lab_arnc_OtherNonOperatingIncomeExpenseLineItems_9916D7AAE113E7D82619EDFC59601B13" xlink:type="arc" />
    <link:label id="lab_us-gaap_IncomeTaxExpenseBenefit_99387B58FF2CFB293F28EDFC59604A0F_negatedLabel_en-US" xlink:label="lab_us-gaap_IncomeTaxExpenseBenefit_99387B58FF2CFB293F28EDFC59604A0F" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xml:lang="en-US">Income tax benefit</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_IncomeTaxExpenseBenefit" xlink:label="loc_us-gaap_IncomeTaxExpenseBenefit_99387B58FF2CFB293F28EDFC59604A0F" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncomeTaxExpenseBenefit_99387B58FF2CFB293F28EDFC59604A0F" xlink:to="lab_us-gaap_IncomeTaxExpenseBenefit_99387B58FF2CFB293F28EDFC59604A0F" xlink:type="arc" />
    <link:label id="lab_us-gaap_GainLossOnDispositionOfAssets1_38786B4DFB7643A7A383EDFC5960DA69_terseLabel_en-US" xlink:label="lab_us-gaap_GainLossOnDispositionOfAssets1_38786B4DFB7643A7A383EDFC5960DA69" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Net loss (gain) from asset sales</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_GainLossOnDispositionOfAssets1" xlink:label="loc_us-gaap_GainLossOnDispositionOfAssets1_38786B4DFB7643A7A383EDFC5960DA69" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_GainLossOnDispositionOfAssets1_38786B4DFB7643A7A383EDFC5960DA69" xlink:to="lab_us-gaap_GainLossOnDispositionOfAssets1_38786B4DFB7643A7A383EDFC5960DA69" xlink:type="arc" />
    <link:label id="lab_us-gaap_CostMethodInvestmentsRealizedGainLoss_A6737EFF4AA44289BE51EDFC59609DD5_terseLabel_en-US" xlink:label="lab_us-gaap_CostMethodInvestmentsRealizedGainLoss_A6737EFF4AA44289BE51EDFC59609DD5" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Pre-tax gain on sale of common stock</link:label>
    <link:label id="lab_us-gaap_CostMethodInvestmentsRealizedGainLoss_A6737EFF4AA44289BE51EDFC59609DD5_label_en-US" xlink:label="lab_us-gaap_CostMethodInvestmentsRealizedGainLoss_A6737EFF4AA44289BE51EDFC59609DD5" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Cost-method Investments, Realized Gain (Loss)</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_CostMethodInvestmentsRealizedGainLoss" xlink:label="loc_us-gaap_CostMethodInvestmentsRealizedGainLoss_A6737EFF4AA44289BE51EDFC59609DD5" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CostMethodInvestmentsRealizedGainLoss_A6737EFF4AA44289BE51EDFC59609DD5" xlink:to="lab_us-gaap_CostMethodInvestmentsRealizedGainLoss_A6737EFF4AA44289BE51EDFC59609DD5" xlink:type="arc" />
    <link:label id="lab_us-gaap_BusinessCombinationProvisionalInformationInitialAccountingIncompleteAdjustmentConsiderationTransferred_94D89084A59036ED1B9DEDFC59616CB2_terseLabel_en-US" xlink:label="lab_us-gaap_BusinessCombinationProvisionalInformationInitialAccountingIncompleteAdjustmentConsiderationTransferred_94D89084A59036ED1B9DEDFC59616CB2" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Business combination, post acquisition closing adjustment</link:label>
    <link:label id="lab_us-gaap_BusinessCombinationProvisionalInformationInitialAccountingIncompleteAdjustmentConsiderationTransferred_94D89084A59036ED1B9DEDFC59616CB2_label_en-US" xlink:label="lab_us-gaap_BusinessCombinationProvisionalInformationInitialAccountingIncompleteAdjustmentConsiderationTransferred_94D89084A59036ED1B9DEDFC59616CB2" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Consideration Transferred</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_BusinessCombinationProvisionalInformationInitialAccountingIncompleteAdjustmentConsiderationTransferred" xlink:label="loc_us-gaap_BusinessCombinationProvisionalInformationInitialAccountingIncompleteAdjustmentConsiderationTransferred_94D89084A59036ED1B9DEDFC59616CB2" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_BusinessCombinationProvisionalInformationInitialAccountingIncompleteAdjustmentConsiderationTransferred_94D89084A59036ED1B9DEDFC59616CB2" xlink:to="lab_us-gaap_BusinessCombinationProvisionalInformationInitialAccountingIncompleteAdjustmentConsiderationTransferred_94D89084A59036ED1B9DEDFC59616CB2" xlink:type="arc" />
    <link:label id="lab_us-gaap_ComprehensiveIncomeNoteTextBlock_7BBCDE3319E54B9FB5DC7C362D922038_terseLabel_en-US" xlink:label="lab_us-gaap_ComprehensiveIncomeNoteTextBlock_7BBCDE3319E54B9FB5DC7C362D922038" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Accumulated Other Comprehensive Loss</link:label>
    <link:label id="lab_us-gaap_ComprehensiveIncomeNoteTextBlock_7BBCDE3319E54B9FB5DC7C362D922038_label_en-US" xlink:label="lab_us-gaap_ComprehensiveIncomeNoteTextBlock_7BBCDE3319E54B9FB5DC7C362D922038" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Comprehensive Income (Loss) Note [Text Block]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ComprehensiveIncomeNoteTextBlock" xlink:label="loc_us-gaap_ComprehensiveIncomeNoteTextBlock_7BBCDE3319E54B9FB5DC7C362D922038" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ComprehensiveIncomeNoteTextBlock_7BBCDE3319E54B9FB5DC7C362D922038" xlink:to="lab_us-gaap_ComprehensiveIncomeNoteTextBlock_7BBCDE3319E54B9FB5DC7C362D922038" xlink:type="arc" />
    <link:label id="lab_us-gaap_ScheduleOfOtherNonoperatingIncomeExpenseTableTextBlock_543AD84EBE81F3268F7EEDFC596A1415_terseLabel_en-US" xlink:label="lab_us-gaap_ScheduleOfOtherNonoperatingIncomeExpenseTableTextBlock_543AD84EBE81F3268F7EEDFC596A1415" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Schedule of Other Expenses (Income), Net</link:label>
    <link:label id="lab_us-gaap_ScheduleOfOtherNonoperatingIncomeExpenseTableTextBlock_543AD84EBE81F3268F7EEDFC596A1415_label_en-US" xlink:label="lab_us-gaap_ScheduleOfOtherNonoperatingIncomeExpenseTableTextBlock_543AD84EBE81F3268F7EEDFC596A1415" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Schedule of Other Nonoperating Income (Expense) [Table Text Block]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ScheduleOfOtherNonoperatingIncomeExpenseTableTextBlock" xlink:label="loc_us-gaap_ScheduleOfOtherNonoperatingIncomeExpenseTableTextBlock_543AD84EBE81F3268F7EEDFC596A1415" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfOtherNonoperatingIncomeExpenseTableTextBlock_543AD84EBE81F3268F7EEDFC596A1415" xlink:to="lab_us-gaap_ScheduleOfOtherNonoperatingIncomeExpenseTableTextBlock_543AD84EBE81F3268F7EEDFC596A1415" xlink:type="arc" />
    <link:label id="lab_us-gaap_InventoryCurrentTable_7546CDB9BDC17CF14F9A06E10C1AD5E7_terseLabel_en-US" xlink:label="lab_us-gaap_InventoryCurrentTable_7546CDB9BDC17CF14F9A06E10C1AD5E7" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Inventory, Current [Table]</link:label>
    <link:label id="lab_us-gaap_InventoryCurrentTable_7546CDB9BDC17CF14F9A06E10C1AD5E7_label_en-US" xlink:label="lab_us-gaap_InventoryCurrentTable_7546CDB9BDC17CF14F9A06E10C1AD5E7" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Inventory, Current [Table]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_InventoryCurrentTable" xlink:label="loc_us-gaap_InventoryCurrentTable_7546CDB9BDC17CF14F9A06E10C1AD5E7" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_InventoryCurrentTable_7546CDB9BDC17CF14F9A06E10C1AD5E7" xlink:to="lab_us-gaap_InventoryCurrentTable_7546CDB9BDC17CF14F9A06E10C1AD5E7" xlink:type="arc" />
    <link:label id="lab_us-gaap_InventoryLineItems_B3514A22C03FB8DAB20A06E10C1B2ABE_terseLabel_en-US" xlink:label="lab_us-gaap_InventoryLineItems_B3514A22C03FB8DAB20A06E10C1B2ABE" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Inventory [Line Items]</link:label>
    <link:label id="lab_us-gaap_InventoryLineItems_B3514A22C03FB8DAB20A06E10C1B2ABE_label_en-US" xlink:label="lab_us-gaap_InventoryLineItems_B3514A22C03FB8DAB20A06E10C1B2ABE" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Inventory [Line Items]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_InventoryLineItems" xlink:label="loc_us-gaap_InventoryLineItems_B3514A22C03FB8DAB20A06E10C1B2ABE" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_InventoryLineItems_B3514A22C03FB8DAB20A06E10C1B2ABE" xlink:to="lab_us-gaap_InventoryLineItems_B3514A22C03FB8DAB20A06E10C1B2ABE" xlink:type="arc" />
    <link:label id="lab_us-gaap_LIFOInventoryAmount_2954CD5DB619ED5FE20806E10C1C279B_terseLabel_en-US" xlink:label="lab_us-gaap_LIFOInventoryAmount_2954CD5DB619ED5FE20806E10C1C279B" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Inventories valued on a LIFO basis</link:label>
    <link:label id="lab_us-gaap_LIFOInventoryAmount_2954CD5DB619ED5FE20806E10C1C279B_label_en-US" xlink:label="lab_us-gaap_LIFOInventoryAmount_2954CD5DB619ED5FE20806E10C1C279B" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">LIFO Inventory Amount</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_LIFOInventoryAmount" xlink:label="loc_us-gaap_LIFOInventoryAmount_2954CD5DB619ED5FE20806E10C1C279B" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LIFOInventoryAmount_2954CD5DB619ED5FE20806E10C1C279B" xlink:to="lab_us-gaap_LIFOInventoryAmount_2954CD5DB619ED5FE20806E10C1C279B" xlink:type="arc" />
    <link:label id="lab_us-gaap_InventoryLIFOReserve_14F66C4342DF818BB50206E10C1C501C_verboseLabel_en-US" xlink:label="lab_us-gaap_InventoryLIFOReserve_14F66C4342DF818BB50206E10C1C501C" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Total inventories valued on an average-cost basis</link:label>
    <link:label id="lab_us-gaap_InventoryLIFOReserve_14F66C4342DF818BB50206E10C1C501C_label_en-US" xlink:label="lab_us-gaap_InventoryLIFOReserve_14F66C4342DF818BB50206E10C1C501C" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Inventory, LIFO Reserve</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_InventoryLIFOReserve" xlink:label="loc_us-gaap_InventoryLIFOReserve_14F66C4342DF818BB50206E10C1C501C" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_InventoryLIFOReserve_14F66C4342DF818BB50206E10C1C501C" xlink:to="lab_us-gaap_InventoryLIFOReserve_14F66C4342DF818BB50206E10C1C501C" xlink:type="arc" />
    <link:label id="lab_us-gaap_InventoryAdjustments_7AFCA22A30710C70AADF06E10C1C08BE_terseLabel_en-US" xlink:label="lab_us-gaap_InventoryAdjustments_7AFCA22A30710C70AADF06E10C1C08BE" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Inventory adjustment recorded in cost of goods sold and inventories</link:label>
    <link:label id="lab_us-gaap_InventoryAdjustments_7AFCA22A30710C70AADF06E10C1C08BE_label_en-US" xlink:label="lab_us-gaap_InventoryAdjustments_7AFCA22A30710C70AADF06E10C1C08BE" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Inventory Adjustments</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_InventoryAdjustments" xlink:label="loc_us-gaap_InventoryAdjustments_7AFCA22A30710C70AADF06E10C1C08BE" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_InventoryAdjustments_7AFCA22A30710C70AADF06E10C1C08BE" xlink:to="lab_us-gaap_InventoryAdjustments_7AFCA22A30710C70AADF06E10C1C08BE" xlink:type="arc" />
    <link:label id="lab_arnc_NumberOfPlants_2F496F772BBADFA05DAD06E1B7E0ECD9_terseLabel_en-US" xlink:label="lab_arnc_NumberOfPlants_2F496F772BBADFA05DAD06E1B7E0ECD9" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Number of plants with inventory adjustments</link:label>
    <link:label id="lab_arnc_NumberOfPlants_2F496F772BBADFA05DAD06E1B7E0ECD9_label_en-US" xlink:label="lab_arnc_NumberOfPlants_2F496F772BBADFA05DAD06E1B7E0ECD9" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Number Of Plants</link:label>
    <link:label id="lab_arnc_NumberOfPlants_2F496F772BBADFA05DAD06E1B7E0ECD9_documentation_en-US" xlink:label="lab_arnc_NumberOfPlants_2F496F772BBADFA05DAD06E1B7E0ECD9" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Number Of Plants</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_NumberOfPlants" xlink:label="loc_arnc_NumberOfPlants_2F496F772BBADFA05DAD06E1B7E0ECD9" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_NumberOfPlants_2F496F772BBADFA05DAD06E1B7E0ECD9" xlink:to="lab_arnc_NumberOfPlants_2F496F772BBADFA05DAD06E1B7E0ECD9" xlink:type="arc" />
    <link:label id="lab_arnc_InvestmentBanksMember_05E7C0426F99501B280EE244A8AED5D2_terseLabel_en-US" xlink:label="lab_arnc_InvestmentBanksMember_05E7C0426F99501B280EE244A8AED5D2" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Investment Banks</link:label>
    <link:label id="lab_arnc_InvestmentBanksMember_05E7C0426F99501B280EE244A8AED5D2_label_en-US" xlink:label="lab_arnc_InvestmentBanksMember_05E7C0426F99501B280EE244A8AED5D2" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Investment Banks [Member]</link:label>
    <link:label id="lab_arnc_InvestmentBanksMember_05E7C0426F99501B280EE244A8AED5D2_documentation_en-US" xlink:label="lab_arnc_InvestmentBanksMember_05E7C0426F99501B280EE244A8AED5D2" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Investment banks.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_InvestmentBanksMember" xlink:label="loc_arnc_InvestmentBanksMember_05E7C0426F99501B280EE244A8AED5D2" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_InvestmentBanksMember_05E7C0426F99501B280EE244A8AED5D2" xlink:to="lab_arnc_InvestmentBanksMember_05E7C0426F99501B280EE244A8AED5D2" xlink:type="arc" />
    <link:label id="lab_us-gaap_SellingGeneralAndAdministrativeExpensesMember_4C7EBA72FFCA9D1EDC8CE244A8B29284_terseLabel_en-US" xlink:label="lab_us-gaap_SellingGeneralAndAdministrativeExpensesMember_4C7EBA72FFCA9D1EDC8CE244A8B29284" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Selling, General Administrative, and Other Expenses</link:label>
    <link:label id="lab_us-gaap_SellingGeneralAndAdministrativeExpensesMember_4C7EBA72FFCA9D1EDC8CE244A8B29284_label_en-US" xlink:label="lab_us-gaap_SellingGeneralAndAdministrativeExpensesMember_4C7EBA72FFCA9D1EDC8CE244A8B29284" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Selling, General and Administrative Expenses [Member]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_SellingGeneralAndAdministrativeExpensesMember" xlink:label="loc_us-gaap_SellingGeneralAndAdministrativeExpensesMember_4C7EBA72FFCA9D1EDC8CE244A8B29284" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SellingGeneralAndAdministrativeExpensesMember_4C7EBA72FFCA9D1EDC8CE244A8B29284" xlink:to="lab_us-gaap_SellingGeneralAndAdministrativeExpensesMember_4C7EBA72FFCA9D1EDC8CE244A8B29284" xlink:type="arc" />
    <link:label id="lab_us-gaap_DiscontinuedOperationEquityMethodInvestmentRetainedAfterDisposalOwnershipInterestPriorToDisposal_EC15B9A8EC4DE3F7221AE244A8B2880B_terseLabel_en-US" xlink:label="lab_us-gaap_DiscontinuedOperationEquityMethodInvestmentRetainedAfterDisposalOwnershipInterestPriorToDisposal_EC15B9A8EC4DE3F7221AE244A8B2880B" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Common stock outstanding percentage</link:label>
    <link:label id="lab_us-gaap_DiscontinuedOperationEquityMethodInvestmentRetainedAfterDisposalOwnershipInterestPriorToDisposal_EC15B9A8EC4DE3F7221AE244A8B2880B_label_en-US" xlink:label="lab_us-gaap_DiscontinuedOperationEquityMethodInvestmentRetainedAfterDisposalOwnershipInterestPriorToDisposal_EC15B9A8EC4DE3F7221AE244A8B2880B" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Discontinued Operation, Equity Method Investment Retained after Disposal, Ownership Interest Prior to Disposal</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DiscontinuedOperationEquityMethodInvestmentRetainedAfterDisposalOwnershipInterestPriorToDisposal" xlink:label="loc_us-gaap_DiscontinuedOperationEquityMethodInvestmentRetainedAfterDisposalOwnershipInterestPriorToDisposal_EC15B9A8EC4DE3F7221AE244A8B2880B" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DiscontinuedOperationEquityMethodInvestmentRetainedAfterDisposalOwnershipInterestPriorToDisposal_EC15B9A8EC4DE3F7221AE244A8B2880B" xlink:to="lab_us-gaap_DiscontinuedOperationEquityMethodInvestmentRetainedAfterDisposalOwnershipInterestPriorToDisposal_EC15B9A8EC4DE3F7221AE244A8B2880B" xlink:type="arc" />
    <link:label id="lab_us-gaap_DiscontinuedOperationEquityMethodInvestmentRetainedAfterDisposalOwnershipInterestAfterDisposal_44C344D4FE0BC9AA7853E244A8B24952_terseLabel_en-US" xlink:label="lab_us-gaap_DiscontinuedOperationEquityMethodInvestmentRetainedAfterDisposalOwnershipInterestAfterDisposal_44C344D4FE0BC9AA7853E244A8B24952" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Percentage of common stock retained</link:label>
    <link:label id="lab_us-gaap_DiscontinuedOperationEquityMethodInvestmentRetainedAfterDisposalOwnershipInterestAfterDisposal_44C344D4FE0BC9AA7853E244A8B24952_label_en-US" xlink:label="lab_us-gaap_DiscontinuedOperationEquityMethodInvestmentRetainedAfterDisposalOwnershipInterestAfterDisposal_44C344D4FE0BC9AA7853E244A8B24952" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Discontinued Operation, Equity Method Investment Retained after Disposal, Ownership Interest after Disposal</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DiscontinuedOperationEquityMethodInvestmentRetainedAfterDisposalOwnershipInterestAfterDisposal" xlink:label="loc_us-gaap_DiscontinuedOperationEquityMethodInvestmentRetainedAfterDisposalOwnershipInterestAfterDisposal_44C344D4FE0BC9AA7853E244A8B24952" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DiscontinuedOperationEquityMethodInvestmentRetainedAfterDisposalOwnershipInterestAfterDisposal_44C344D4FE0BC9AA7853E244A8B24952" xlink:to="lab_us-gaap_DiscontinuedOperationEquityMethodInvestmentRetainedAfterDisposalOwnershipInterestAfterDisposal_44C344D4FE0BC9AA7853E244A8B24952" xlink:type="arc" />
    <link:label id="lab_arnc_DiscontinuedOperationCommonStockRetainedAfterDisposal_DB18D9FB80EE233A83A3E244A8B27136_terseLabel_en-US" xlink:label="lab_arnc_DiscontinuedOperationCommonStockRetainedAfterDisposal_DB18D9FB80EE233A83A3E244A8B27136" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Number of common stock retained (in shares)</link:label>
    <link:label id="lab_arnc_DiscontinuedOperationCommonStockRetainedAfterDisposal_DB18D9FB80EE233A83A3E244A8B27136_label_en-US" xlink:label="lab_arnc_DiscontinuedOperationCommonStockRetainedAfterDisposal_DB18D9FB80EE233A83A3E244A8B27136" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Discontinued Operation Common Stock Retained After Disposal</link:label>
    <link:label id="lab_arnc_DiscontinuedOperationCommonStockRetainedAfterDisposal_DB18D9FB80EE233A83A3E244A8B27136_documentation_en-US" xlink:label="lab_arnc_DiscontinuedOperationCommonStockRetainedAfterDisposal_DB18D9FB80EE233A83A3E244A8B27136" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Discontinued operation common stock retained after disposal.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_DiscontinuedOperationCommonStockRetainedAfterDisposal" xlink:label="loc_arnc_DiscontinuedOperationCommonStockRetainedAfterDisposal_DB18D9FB80EE233A83A3E244A8B27136" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_DiscontinuedOperationCommonStockRetainedAfterDisposal_DB18D9FB80EE233A83A3E244A8B27136" xlink:to="lab_arnc_DiscontinuedOperationCommonStockRetainedAfterDisposal_DB18D9FB80EE233A83A3E244A8B27136" xlink:type="arc" />
    <link:label id="lab_us-gaap_InvestmentsInAndAdvancesToAffiliatesAmountOfEquity_6BCF0BCAF295556E0A16E244A8B28B82_terseLabel_en-US" xlink:label="lab_us-gaap_InvestmentsInAndAdvancesToAffiliatesAmountOfEquity_6BCF0BCAF295556E0A16E244A8B28B82" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Investment in common stock of Alcoa Corporation</link:label>
    <link:label id="lab_us-gaap_InvestmentsInAndAdvancesToAffiliatesAmountOfEquity_6BCF0BCAF295556E0A16E244A8B28B82_label_en-US" xlink:label="lab_us-gaap_InvestmentsInAndAdvancesToAffiliatesAmountOfEquity_6BCF0BCAF295556E0A16E244A8B28B82" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Investments in and Advances to Affiliates, Amount of Equity</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_InvestmentsInAndAdvancesToAffiliatesAmountOfEquity" xlink:label="loc_us-gaap_InvestmentsInAndAdvancesToAffiliatesAmountOfEquity_6BCF0BCAF295556E0A16E244A8B28B82" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_InvestmentsInAndAdvancesToAffiliatesAmountOfEquity_6BCF0BCAF295556E0A16E244A8B28B82" xlink:to="lab_us-gaap_InvestmentsInAndAdvancesToAffiliatesAmountOfEquity_6BCF0BCAF295556E0A16E244A8B28B82" xlink:type="arc" />
    <link:label id="lab_us-gaap_SaleOfStockNumberOfSharesIssuedInTransaction_51CF8AA113F7A52CD025E244A8B20EE1_terseLabel_en-US" xlink:label="lab_us-gaap_SaleOfStockNumberOfSharesIssuedInTransaction_51CF8AA113F7A52CD025E244A8B20EE1" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Common stock sold (in shares)</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_SaleOfStockNumberOfSharesIssuedInTransaction" xlink:label="loc_us-gaap_SaleOfStockNumberOfSharesIssuedInTransaction_51CF8AA113F7A52CD025E244A8B20EE1" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SaleOfStockNumberOfSharesIssuedInTransaction_51CF8AA113F7A52CD025E244A8B20EE1" xlink:to="lab_us-gaap_SaleOfStockNumberOfSharesIssuedInTransaction_51CF8AA113F7A52CD025E244A8B20EE1" xlink:type="arc" />
    <link:label id="lab_us-gaap_SaleOfStockPricePerShare_D0872F040268E49C3A8AE244A8B2EA5E_verboseLabel_en-US" xlink:label="lab_us-gaap_SaleOfStockPricePerShare_D0872F040268E49C3A8AE244A8B2EA5E" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Common stock sold per share (usd per share)</link:label>
    <link:label id="lab_us-gaap_SaleOfStockPricePerShare_D0872F040268E49C3A8AE244A8B2EA5E_label_en-US" xlink:label="lab_us-gaap_SaleOfStockPricePerShare_D0872F040268E49C3A8AE244A8B2EA5E" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Sale of Stock, Price Per Share</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_SaleOfStockPricePerShare" xlink:label="loc_us-gaap_SaleOfStockPricePerShare_D0872F040268E49C3A8AE244A8B2EA5E" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SaleOfStockPricePerShare_D0872F040268E49C3A8AE244A8B2EA5E" xlink:to="lab_us-gaap_SaleOfStockPricePerShare_D0872F040268E49C3A8AE244A8B2EA5E" xlink:type="arc" />
    <link:label id="lab_us-gaap_ProceedsFromDivestitureOfInterestInSubsidiariesAndAffiliates_F129457CEEFC460AE636E244A8B20FF8_terseLabel_en-US" xlink:label="lab_us-gaap_ProceedsFromDivestitureOfInterestInSubsidiariesAndAffiliates_F129457CEEFC460AE636E244A8B20FF8" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Cash proceeds sale of common stock</link:label>
    <link:label id="lab_us-gaap_ProceedsFromDivestitureOfInterestInSubsidiariesAndAffiliates_F129457CEEFC460AE636E244A8B20FF8_label_en-US" xlink:label="lab_us-gaap_ProceedsFromDivestitureOfInterestInSubsidiariesAndAffiliates_F129457CEEFC460AE636E244A8B20FF8" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Proceeds from Divestiture of Interest in Subsidiaries and Affiliates</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ProceedsFromDivestitureOfInterestInSubsidiariesAndAffiliates" xlink:label="loc_us-gaap_ProceedsFromDivestitureOfInterestInSubsidiariesAndAffiliates_F129457CEEFC460AE636E244A8B20FF8" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ProceedsFromDivestitureOfInterestInSubsidiariesAndAffiliates_F129457CEEFC460AE636E244A8B20FF8" xlink:to="lab_us-gaap_ProceedsFromDivestitureOfInterestInSubsidiariesAndAffiliates_F129457CEEFC460AE636E244A8B20FF8" xlink:type="arc" />
    <link:label id="lab_arnc_NumberOfCounterparties_7B045D06F88E6DAC2730E244A8B2F3BE_terseLabel_en-US" xlink:label="lab_arnc_NumberOfCounterparties_7B045D06F88E6DAC2730E244A8B2F3BE" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Number of counterparties</link:label>
    <link:label id="lab_arnc_NumberOfCounterparties_7B045D06F88E6DAC2730E244A8B2F3BE_label_en-US" xlink:label="lab_arnc_NumberOfCounterparties_7B045D06F88E6DAC2730E244A8B2F3BE" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Number Of Counterparties</link:label>
    <link:label id="lab_arnc_NumberOfCounterparties_7B045D06F88E6DAC2730E244A8B2F3BE_documentation_en-US" xlink:label="lab_arnc_NumberOfCounterparties_7B045D06F88E6DAC2730E244A8B2F3BE" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Number Of Counterparties</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_NumberOfCounterparties" xlink:label="loc_arnc_NumberOfCounterparties_7B045D06F88E6DAC2730E244A8B2F3BE" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_NumberOfCounterparties_7B045D06F88E6DAC2730E244A8B2F3BE" xlink:to="lab_arnc_NumberOfCounterparties_7B045D06F88E6DAC2730E244A8B2F3BE" xlink:type="arc" />
    <link:label id="lab_arnc_PaymentGuaranteesRelatedToDisposalGroup_486FC2607C4463D7D2DDE244A8B26EEC_terseLabel_en-US" xlink:label="lab_arnc_PaymentGuaranteesRelatedToDisposalGroup_486FC2607C4463D7D2DDE244A8B26EEC" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Payment guarantees related to disposal group</link:label>
    <link:label id="lab_arnc_PaymentGuaranteesRelatedToDisposalGroup_486FC2607C4463D7D2DDE244A8B26EEC_label_en-US" xlink:label="lab_arnc_PaymentGuaranteesRelatedToDisposalGroup_486FC2607C4463D7D2DDE244A8B26EEC" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Payment Guarantees Related To Disposal Group</link:label>
    <link:label id="lab_arnc_PaymentGuaranteesRelatedToDisposalGroup_486FC2607C4463D7D2DDE244A8B26EEC_documentation_en-US" xlink:label="lab_arnc_PaymentGuaranteesRelatedToDisposalGroup_486FC2607C4463D7D2DDE244A8B26EEC" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Payment Guarantees Related To Disposal Group</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_PaymentGuaranteesRelatedToDisposalGroup" xlink:label="loc_arnc_PaymentGuaranteesRelatedToDisposalGroup_486FC2607C4463D7D2DDE244A8B26EEC" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_PaymentGuaranteesRelatedToDisposalGroup_486FC2607C4463D7D2DDE244A8B26EEC" xlink:to="lab_arnc_PaymentGuaranteesRelatedToDisposalGroup_486FC2607C4463D7D2DDE244A8B26EEC" xlink:type="arc" />
    <link:label id="lab_us-gaap_PaymentsForProceedsFromOtherInvestingActivities_BF264B2887E576C1E68CE244A8B205D8_negatedTerseLabel_en-US" xlink:label="lab_us-gaap_PaymentsForProceedsFromOtherInvestingActivities_BF264B2887E576C1E68CE244A8B205D8" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:type="resource" xml:lang="en-US">Proceeds from Alcoa Corporation's sale of Yadkin Hydroelectric Project</link:label>
    <link:label id="lab_us-gaap_PaymentsForProceedsFromOtherInvestingActivities_BF264B2887E576C1E68CE244A8B205D8_label_en-US" xlink:label="lab_us-gaap_PaymentsForProceedsFromOtherInvestingActivities_BF264B2887E576C1E68CE244A8B205D8" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Payments for (Proceeds from) Other Investing Activities</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PaymentsForProceedsFromOtherInvestingActivities" xlink:label="loc_us-gaap_PaymentsForProceedsFromOtherInvestingActivities_BF264B2887E576C1E68CE244A8B205D8" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PaymentsForProceedsFromOtherInvestingActivities_BF264B2887E576C1E68CE244A8B205D8" xlink:to="lab_us-gaap_PaymentsForProceedsFromOtherInvestingActivities_BF264B2887E576C1E68CE244A8B205D8" xlink:type="arc" />
    <link:label id="lab_arnc_SeparationTransactionCostsBeforeTax_6FFCE7A1922213EA34E0E244A8B2B585_terseLabel_en-US" xlink:label="lab_arnc_SeparationTransactionCostsBeforeTax_6FFCE7A1922213EA34E0E244A8B2B585" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Costs related to separation transaction, pre-tax</link:label>
    <link:label id="lab_arnc_SeparationTransactionCostsBeforeTax_6FFCE7A1922213EA34E0E244A8B2B585_label_en-US" xlink:label="lab_arnc_SeparationTransactionCostsBeforeTax_6FFCE7A1922213EA34E0E244A8B2B585" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Separation Transaction Costs Before Tax</link:label>
    <link:label id="lab_arnc_SeparationTransactionCostsBeforeTax_6FFCE7A1922213EA34E0E244A8B2B585_documentation_en-US" xlink:label="lab_arnc_SeparationTransactionCostsBeforeTax_6FFCE7A1922213EA34E0E244A8B2B585" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Separation transaction costs before tax.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_SeparationTransactionCostsBeforeTax" xlink:label="loc_arnc_SeparationTransactionCostsBeforeTax_6FFCE7A1922213EA34E0E244A8B2B585" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_SeparationTransactionCostsBeforeTax_6FFCE7A1922213EA34E0E244A8B2B585" xlink:to="lab_arnc_SeparationTransactionCostsBeforeTax_6FFCE7A1922213EA34E0E244A8B2B585" xlink:type="arc" />
    <link:label id="lab_arnc_SeparationTransactionCostsNetOfTax_87F923FA2F517953FB84E244A8B25FBB_terseLabel_en-US" xlink:label="lab_arnc_SeparationTransactionCostsNetOfTax_87F923FA2F517953FB84E244A8B25FBB" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Costs related to separation transaction, after-tax</link:label>
    <link:label id="lab_arnc_SeparationTransactionCostsNetOfTax_87F923FA2F517953FB84E244A8B25FBB_label_en-US" xlink:label="lab_arnc_SeparationTransactionCostsNetOfTax_87F923FA2F517953FB84E244A8B25FBB" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Separation Transaction Costs Net Of Tax</link:label>
    <link:label id="lab_arnc_SeparationTransactionCostsNetOfTax_87F923FA2F517953FB84E244A8B25FBB_documentation_en-US" xlink:label="lab_arnc_SeparationTransactionCostsNetOfTax_87F923FA2F517953FB84E244A8B25FBB" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Separation transaction costs net of tax.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_SeparationTransactionCostsNetOfTax" xlink:label="loc_arnc_SeparationTransactionCostsNetOfTax_87F923FA2F517953FB84E244A8B25FBB" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_SeparationTransactionCostsNetOfTax_87F923FA2F517953FB84E244A8B25FBB" xlink:to="lab_arnc_SeparationTransactionCostsNetOfTax_87F923FA2F517953FB84E244A8B25FBB" xlink:type="arc" />
    <link:label id="lab_arnc_CapitalExpendituresAndDebtIssuanceCostsRelatedToSeparation_309825D8CA0587A0971CE244A8B22BE4_terseLabel_en-US" xlink:label="lab_arnc_CapitalExpendituresAndDebtIssuanceCostsRelatedToSeparation_309825D8CA0587A0971CE244A8B22BE4" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Debt issuance and capital expenditures incurred</link:label>
    <link:label id="lab_arnc_CapitalExpendituresAndDebtIssuanceCostsRelatedToSeparation_309825D8CA0587A0971CE244A8B22BE4_label_en-US" xlink:label="lab_arnc_CapitalExpendituresAndDebtIssuanceCostsRelatedToSeparation_309825D8CA0587A0971CE244A8B22BE4" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Capital Expenditures And Debt Issuance Costs Related To Separation</link:label>
    <link:label id="lab_arnc_CapitalExpendituresAndDebtIssuanceCostsRelatedToSeparation_309825D8CA0587A0971CE244A8B22BE4_documentation_en-US" xlink:label="lab_arnc_CapitalExpendituresAndDebtIssuanceCostsRelatedToSeparation_309825D8CA0587A0971CE244A8B22BE4" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Capital expenditures and debt issuance costs related to separation.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_CapitalExpendituresAndDebtIssuanceCostsRelatedToSeparation" xlink:label="loc_arnc_CapitalExpendituresAndDebtIssuanceCostsRelatedToSeparation_309825D8CA0587A0971CE244A8B22BE4" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_CapitalExpendituresAndDebtIssuanceCostsRelatedToSeparation_309825D8CA0587A0971CE244A8B22BE4" xlink:to="lab_arnc_CapitalExpendituresAndDebtIssuanceCostsRelatedToSeparation_309825D8CA0587A0971CE244A8B22BE4" xlink:type="arc" />
    <link:label id="lab_us-gaap_AssetImpairmentCharges_F60984C7974689204C2DE244A8B20B33_positiveLabel_en-US" xlink:label="lab_us-gaap_AssetImpairmentCharges_F60984C7974689204C2DE244A8B20B33" xlink:role="http://www.xbrl.org/2003/role/positiveLabel" xlink:type="resource" xml:lang="en-US">Impairment charges</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AssetImpairmentCharges" xlink:label="loc_us-gaap_AssetImpairmentCharges_F60984C7974689204C2DE244A8B20B33" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AssetImpairmentCharges_F60984C7974689204C2DE244A8B20B33" xlink:to="lab_us-gaap_AssetImpairmentCharges_F60984C7974689204C2DE244A8B20B33" xlink:type="arc" />
    <link:label id="lab_arnc_DiscontinuedOperationConversionRatio_F7C81A00D8A48C59B9A3E244A8B20438_terseLabel_en-US" xlink:label="lab_arnc_DiscontinuedOperationConversionRatio_F7C81A00D8A48C59B9A3E244A8B20438" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Discontinued operation conversion rate</link:label>
    <link:label id="lab_arnc_DiscontinuedOperationConversionRatio_F7C81A00D8A48C59B9A3E244A8B20438_label_en-US" xlink:label="lab_arnc_DiscontinuedOperationConversionRatio_F7C81A00D8A48C59B9A3E244A8B20438" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Discontinued Operation Conversion Ratio</link:label>
    <link:label id="lab_arnc_DiscontinuedOperationConversionRatio_F7C81A00D8A48C59B9A3E244A8B20438_documentation_en-US" xlink:label="lab_arnc_DiscontinuedOperationConversionRatio_F7C81A00D8A48C59B9A3E244A8B20438" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Discontinued operation conversion ratio.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_DiscontinuedOperationConversionRatio" xlink:label="loc_arnc_DiscontinuedOperationConversionRatio_F7C81A00D8A48C59B9A3E244A8B20438" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_DiscontinuedOperationConversionRatio_F7C81A00D8A48C59B9A3E244A8B20438" xlink:to="lab_arnc_DiscontinuedOperationConversionRatio_F7C81A00D8A48C59B9A3E244A8B20438" xlink:type="arc" />
    <link:label id="lab_us-gaap_SaleOfStockPercentageOfOwnershipAfterTransaction_5C726C01A4F67C720427E244A8B2BF71_terseLabel_en-US" xlink:label="lab_us-gaap_SaleOfStockPercentageOfOwnershipAfterTransaction_5C726C01A4F67C720427E244A8B2BF71" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Percentage ownership in Alcoa after sale</link:label>
    <link:label id="lab_us-gaap_SaleOfStockPercentageOfOwnershipAfterTransaction_5C726C01A4F67C720427E244A8B2BF71_label_en-US" xlink:label="lab_us-gaap_SaleOfStockPercentageOfOwnershipAfterTransaction_5C726C01A4F67C720427E244A8B2BF71" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Sale of Stock, Percentage of Ownership after Transaction</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_SaleOfStockPercentageOfOwnershipAfterTransaction" xlink:label="loc_us-gaap_SaleOfStockPercentageOfOwnershipAfterTransaction_5C726C01A4F67C720427E244A8B2BF71" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SaleOfStockPercentageOfOwnershipAfterTransaction_5C726C01A4F67C720427E244A8B2BF71" xlink:to="lab_us-gaap_SaleOfStockPercentageOfOwnershipAfterTransaction_5C726C01A4F67C720427E244A8B2BF71" xlink:type="arc" />
    <link:label id="lab_us-gaap_PensionAndOtherPostretirementBenefitsDisclosureTextBlock_48E9315DE224AFC67CFD7C362F837636_terseLabel_en-US" xlink:label="lab_us-gaap_PensionAndOtherPostretirementBenefitsDisclosureTextBlock_48E9315DE224AFC67CFD7C362F837636" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Pension and Other Postretirement Benefits</link:label>
    <link:label id="lab_us-gaap_PensionAndOtherPostretirementBenefitsDisclosureTextBlock_48E9315DE224AFC67CFD7C362F837636_label_en-US" xlink:label="lab_us-gaap_PensionAndOtherPostretirementBenefitsDisclosureTextBlock_48E9315DE224AFC67CFD7C362F837636" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Pension and Other Postretirement Benefits Disclosure [Text Block]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PensionAndOtherPostretirementBenefitsDisclosureTextBlock" xlink:label="loc_us-gaap_PensionAndOtherPostretirementBenefitsDisclosureTextBlock_48E9315DE224AFC67CFD7C362F837636" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PensionAndOtherPostretirementBenefitsDisclosureTextBlock_48E9315DE224AFC67CFD7C362F837636" xlink:to="lab_us-gaap_PensionAndOtherPostretirementBenefitsDisclosureTextBlock_48E9315DE224AFC67CFD7C362F837636" xlink:type="arc" />
    <link:label id="lab_us-gaap_ConcentrationRiskByBenchmarkAxis_12E6E3AC47F663997B717C36304FFCCA_terseLabel_en-US" xlink:label="lab_us-gaap_ConcentrationRiskByBenchmarkAxis_12E6E3AC47F663997B717C36304FFCCA" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Concentration Risk Benchmark [Axis]</link:label>
    <link:label id="lab_us-gaap_ConcentrationRiskByBenchmarkAxis_12E6E3AC47F663997B717C36304FFCCA_label_en-US" xlink:label="lab_us-gaap_ConcentrationRiskByBenchmarkAxis_12E6E3AC47F663997B717C36304FFCCA" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Concentration Risk Benchmark [Axis]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ConcentrationRiskByBenchmarkAxis" xlink:label="loc_us-gaap_ConcentrationRiskByBenchmarkAxis_12E6E3AC47F663997B717C36304FFCCA" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ConcentrationRiskByBenchmarkAxis_12E6E3AC47F663997B717C36304FFCCA" xlink:to="lab_us-gaap_ConcentrationRiskByBenchmarkAxis_12E6E3AC47F663997B717C36304FFCCA" xlink:type="arc" />
    <link:label id="lab_us-gaap_ConcentrationRiskBenchmarkDomain_B4D1EEAE703E14C81AEE7C36304F7F1C_terseLabel_en-US" xlink:label="lab_us-gaap_ConcentrationRiskBenchmarkDomain_B4D1EEAE703E14C81AEE7C36304F7F1C" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Concentration Risk Benchmark [Domain]</link:label>
    <link:label id="lab_us-gaap_ConcentrationRiskBenchmarkDomain_B4D1EEAE703E14C81AEE7C36304F7F1C_label_en-US" xlink:label="lab_us-gaap_ConcentrationRiskBenchmarkDomain_B4D1EEAE703E14C81AEE7C36304F7F1C" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Concentration Risk Benchmark [Domain]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ConcentrationRiskBenchmarkDomain" xlink:label="loc_us-gaap_ConcentrationRiskBenchmarkDomain_B4D1EEAE703E14C81AEE7C36304F7F1C" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ConcentrationRiskBenchmarkDomain_B4D1EEAE703E14C81AEE7C36304F7F1C" xlink:to="lab_us-gaap_ConcentrationRiskBenchmarkDomain_B4D1EEAE703E14C81AEE7C36304F7F1C" xlink:type="arc" />
    <link:label id="lab_us-gaap_SalesRevenueSegmentMember_D635BCC9C926801525B17C36304FAC9A_terseLabel_en-US" xlink:label="lab_us-gaap_SalesRevenueSegmentMember_D635BCC9C926801525B17C36304FAC9A" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Sales Revenue, Segment</link:label>
    <link:label id="lab_us-gaap_SalesRevenueSegmentMember_D635BCC9C926801525B17C36304FAC9A_label_en-US" xlink:label="lab_us-gaap_SalesRevenueSegmentMember_D635BCC9C926801525B17C36304FAC9A" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Sales Revenue, Segment [Member]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_SalesRevenueSegmentMember" xlink:label="loc_us-gaap_SalesRevenueSegmentMember_D635BCC9C926801525B17C36304FAC9A" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SalesRevenueSegmentMember_D635BCC9C926801525B17C36304FAC9A" xlink:to="lab_us-gaap_SalesRevenueSegmentMember_D635BCC9C926801525B17C36304FAC9A" xlink:type="arc" />
    <link:label id="lab_us-gaap_ConcentrationRiskByTypeAxis_6683DBD7712285EAC8367C36304F99AF_terseLabel_en-US" xlink:label="lab_us-gaap_ConcentrationRiskByTypeAxis_6683DBD7712285EAC8367C36304F99AF" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Concentration Risk Type [Axis]</link:label>
    <link:label id="lab_us-gaap_ConcentrationRiskByTypeAxis_6683DBD7712285EAC8367C36304F99AF_label_en-US" xlink:label="lab_us-gaap_ConcentrationRiskByTypeAxis_6683DBD7712285EAC8367C36304F99AF" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Concentration Risk Type [Axis]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ConcentrationRiskByTypeAxis" xlink:label="loc_us-gaap_ConcentrationRiskByTypeAxis_6683DBD7712285EAC8367C36304F99AF" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ConcentrationRiskByTypeAxis_6683DBD7712285EAC8367C36304F99AF" xlink:to="lab_us-gaap_ConcentrationRiskByTypeAxis_6683DBD7712285EAC8367C36304F99AF" xlink:type="arc" />
    <link:label id="lab_us-gaap_ConcentrationRiskTypeDomain_61B350DA2FC20D3F79997C36304FE6B4_terseLabel_en-US" xlink:label="lab_us-gaap_ConcentrationRiskTypeDomain_61B350DA2FC20D3F79997C36304FE6B4" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Concentration Risk Type [Domain]</link:label>
    <link:label id="lab_us-gaap_ConcentrationRiskTypeDomain_61B350DA2FC20D3F79997C36304FE6B4_label_en-US" xlink:label="lab_us-gaap_ConcentrationRiskTypeDomain_61B350DA2FC20D3F79997C36304FE6B4" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Concentration Risk Type [Domain]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ConcentrationRiskTypeDomain" xlink:label="loc_us-gaap_ConcentrationRiskTypeDomain_61B350DA2FC20D3F79997C36304FE6B4" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ConcentrationRiskTypeDomain_61B350DA2FC20D3F79997C36304FE6B4" xlink:to="lab_us-gaap_ConcentrationRiskTypeDomain_61B350DA2FC20D3F79997C36304FE6B4" xlink:type="arc" />
    <link:label id="lab_us-gaap_ProductConcentrationRiskMember_B26790D862DC36A8908A7C36304FED5D_terseLabel_en-US" xlink:label="lab_us-gaap_ProductConcentrationRiskMember_B26790D862DC36A8908A7C36304FED5D" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Product Concentration Risk</link:label>
    <link:label id="lab_us-gaap_ProductConcentrationRiskMember_B26790D862DC36A8908A7C36304FED5D_label_en-US" xlink:label="lab_us-gaap_ProductConcentrationRiskMember_B26790D862DC36A8908A7C36304FED5D" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Product Concentration Risk [Member]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ProductConcentrationRiskMember" xlink:label="loc_us-gaap_ProductConcentrationRiskMember_B26790D862DC36A8908A7C36304FED5D" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ProductConcentrationRiskMember_B26790D862DC36A8908A7C36304FED5D" xlink:to="lab_us-gaap_ProductConcentrationRiskMember_B26790D862DC36A8908A7C36304FED5D" xlink:type="arc" />
    <link:label id="lab_us-gaap_NumberOfReportableSegments_B96111218FD2D36CED477C36304FB963_terseLabel_en-US" xlink:label="lab_us-gaap_NumberOfReportableSegments_B96111218FD2D36CED477C36304FB963" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Number of reportable segments</link:label>
    <link:label id="lab_us-gaap_NumberOfReportableSegments_B96111218FD2D36CED477C36304FB963_label_en-US" xlink:label="lab_us-gaap_NumberOfReportableSegments_B96111218FD2D36CED477C36304FB963" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Number of Reportable Segments</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_NumberOfReportableSegments" xlink:label="loc_us-gaap_NumberOfReportableSegments_B96111218FD2D36CED477C36304FB963" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_NumberOfReportableSegments_B96111218FD2D36CED477C36304FB963" xlink:to="lab_us-gaap_NumberOfReportableSegments_B96111218FD2D36CED477C36304FB963" xlink:type="arc" />
    <link:label id="lab_arnc_SalesPercentage_9D1CC5D2377789D064987C36304FB427_terseLabel_en-US" xlink:label="lab_arnc_SalesPercentage_9D1CC5D2377789D064987C36304FB427" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Sales percentage</link:label>
    <link:label id="lab_arnc_SalesPercentage_9D1CC5D2377789D064987C36304FB427_label_en-US" xlink:label="lab_arnc_SalesPercentage_9D1CC5D2377789D064987C36304FB427" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Sales Percentage</link:label>
    <link:label id="lab_arnc_SalesPercentage_9D1CC5D2377789D064987C36304FB427_documentation_en-US" xlink:label="lab_arnc_SalesPercentage_9D1CC5D2377789D064987C36304FB427" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Sales Percentage</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_SalesPercentage" xlink:label="loc_arnc_SalesPercentage_9D1CC5D2377789D064987C36304FB427" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_SalesPercentage_9D1CC5D2377789D064987C36304FB427" xlink:to="lab_arnc_SalesPercentage_9D1CC5D2377789D064987C36304FB427" xlink:type="arc" />
    <link:label id="lab_us-gaap_IncomeTaxContingencyTable_4E529BCF85F2E66BE10A0D704726DF7E_terseLabel_en-US" xlink:label="lab_us-gaap_IncomeTaxContingencyTable_4E529BCF85F2E66BE10A0D704726DF7E" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Income Tax Contingency [Table]</link:label>
    <link:label id="lab_us-gaap_IncomeTaxContingencyTable_4E529BCF85F2E66BE10A0D704726DF7E_label_en-US" xlink:label="lab_us-gaap_IncomeTaxContingencyTable_4E529BCF85F2E66BE10A0D704726DF7E" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Income Tax Contingency [Table]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_IncomeTaxContingencyTable" xlink:label="loc_us-gaap_IncomeTaxContingencyTable_4E529BCF85F2E66BE10A0D704726DF7E" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncomeTaxContingencyTable_4E529BCF85F2E66BE10A0D704726DF7E" xlink:to="lab_us-gaap_IncomeTaxContingencyTable_4E529BCF85F2E66BE10A0D704726DF7E" xlink:type="arc" />
    <link:label id="lab_us-gaap_ValuationAllowanceByDeferredTaxAssetAxis_13C10FEA07429428D9C00D7047265776_terseLabel_en-US" xlink:label="lab_us-gaap_ValuationAllowanceByDeferredTaxAssetAxis_13C10FEA07429428D9C00D7047265776" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Valuation Allowance by Deferred Tax Asset [Axis]</link:label>
    <link:label id="lab_us-gaap_ValuationAllowanceByDeferredTaxAssetAxis_13C10FEA07429428D9C00D7047265776_label_en-US" xlink:label="lab_us-gaap_ValuationAllowanceByDeferredTaxAssetAxis_13C10FEA07429428D9C00D7047265776" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Valuation Allowance by Deferred Tax Asset [Axis]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ValuationAllowanceByDeferredTaxAssetAxis" xlink:label="loc_us-gaap_ValuationAllowanceByDeferredTaxAssetAxis_13C10FEA07429428D9C00D7047265776" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ValuationAllowanceByDeferredTaxAssetAxis_13C10FEA07429428D9C00D7047265776" xlink:to="lab_us-gaap_ValuationAllowanceByDeferredTaxAssetAxis_13C10FEA07429428D9C00D7047265776" xlink:type="arc" />
    <link:label id="lab_us-gaap_DeferredTaxAssetDomain_997F64B230021E28A1A40D7047264E1A_terseLabel_en-US" xlink:label="lab_us-gaap_DeferredTaxAssetDomain_997F64B230021E28A1A40D7047264E1A" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Deferred Tax Asset [Domain]</link:label>
    <link:label id="lab_us-gaap_DeferredTaxAssetDomain_997F64B230021E28A1A40D7047264E1A_label_en-US" xlink:label="lab_us-gaap_DeferredTaxAssetDomain_997F64B230021E28A1A40D7047264E1A" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Deferred Tax Asset [Domain]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DeferredTaxAssetDomain" xlink:label="loc_us-gaap_DeferredTaxAssetDomain_997F64B230021E28A1A40D7047264E1A" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DeferredTaxAssetDomain_997F64B230021E28A1A40D7047264E1A" xlink:to="lab_us-gaap_DeferredTaxAssetDomain_997F64B230021E28A1A40D7047264E1A" xlink:type="arc" />
    <link:label id="lab_arnc_OtherNetStateDeferredTaxAssetMember_96AF1D2C312E4CCB67D70D70472699E7_terseLabel_en-US" xlink:label="lab_arnc_OtherNetStateDeferredTaxAssetMember_96AF1D2C312E4CCB67D70D70472699E7" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Other Net State Deferred Tax Asset</link:label>
    <link:label id="lab_arnc_OtherNetStateDeferredTaxAssetMember_96AF1D2C312E4CCB67D70D70472699E7_label_en-US" xlink:label="lab_arnc_OtherNetStateDeferredTaxAssetMember_96AF1D2C312E4CCB67D70D70472699E7" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Other Net State Deferred Tax Asset [Member]</link:label>
    <link:label id="lab_arnc_OtherNetStateDeferredTaxAssetMember_96AF1D2C312E4CCB67D70D70472699E7_documentation_en-US" xlink:label="lab_arnc_OtherNetStateDeferredTaxAssetMember_96AF1D2C312E4CCB67D70D70472699E7" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Other Net State Deferred Tax Asset</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_OtherNetStateDeferredTaxAssetMember" xlink:label="loc_arnc_OtherNetStateDeferredTaxAssetMember_96AF1D2C312E4CCB67D70D70472699E7" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_OtherNetStateDeferredTaxAssetMember_96AF1D2C312E4CCB67D70D70472699E7" xlink:to="lab_arnc_OtherNetStateDeferredTaxAssetMember_96AF1D2C312E4CCB67D70D70472699E7" xlink:type="arc" />
    <link:label id="lab_us-gaap_IncomeTaxAuthorityNameAxis_4345C133563468CD5EA10D704726AF95_terseLabel_en-US" xlink:label="lab_us-gaap_IncomeTaxAuthorityNameAxis_4345C133563468CD5EA10D704726AF95" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Income Tax Authority, Name [Axis]</link:label>
    <link:label id="lab_us-gaap_IncomeTaxAuthorityNameAxis_4345C133563468CD5EA10D704726AF95_label_en-US" xlink:label="lab_us-gaap_IncomeTaxAuthorityNameAxis_4345C133563468CD5EA10D704726AF95" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Income Tax Authority, Name [Axis]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_IncomeTaxAuthorityNameAxis" xlink:label="loc_us-gaap_IncomeTaxAuthorityNameAxis_4345C133563468CD5EA10D704726AF95" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncomeTaxAuthorityNameAxis_4345C133563468CD5EA10D704726AF95" xlink:to="lab_us-gaap_IncomeTaxAuthorityNameAxis_4345C133563468CD5EA10D704726AF95" xlink:type="arc" />
    <link:label id="lab_us-gaap_IncomeTaxAuthorityNameDomain_A359661D95A96C6A806B0D7047355589_terseLabel_en-US" xlink:label="lab_us-gaap_IncomeTaxAuthorityNameDomain_A359661D95A96C6A806B0D7047355589" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Income Tax Authority, Name [Domain]</link:label>
    <link:label id="lab_us-gaap_IncomeTaxAuthorityNameDomain_A359661D95A96C6A806B0D7047355589_label_en-US" xlink:label="lab_us-gaap_IncomeTaxAuthorityNameDomain_A359661D95A96C6A806B0D7047355589" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Income Tax Authority, Name [Domain]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_IncomeTaxAuthorityNameDomain" xlink:label="loc_us-gaap_IncomeTaxAuthorityNameDomain_A359661D95A96C6A806B0D7047355589" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncomeTaxAuthorityNameDomain_A359661D95A96C6A806B0D7047355589" xlink:to="lab_us-gaap_IncomeTaxAuthorityNameDomain_A359661D95A96C6A806B0D7047355589" xlink:type="arc" />
    <link:label id="lab_us-gaap_InternalRevenueServiceIRSMember_1A05637D539DF20F7F680D704735B52C_terseLabel_en-US" xlink:label="lab_us-gaap_InternalRevenueServiceIRSMember_1A05637D539DF20F7F680D704735B52C" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Internal Revenue Service IRS</link:label>
    <link:label id="lab_us-gaap_InternalRevenueServiceIRSMember_1A05637D539DF20F7F680D704735B52C_label_en-US" xlink:label="lab_us-gaap_InternalRevenueServiceIRSMember_1A05637D539DF20F7F680D704735B52C" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Internal Revenue Service (IRS) [Member]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_InternalRevenueServiceIRSMember" xlink:label="loc_us-gaap_InternalRevenueServiceIRSMember_1A05637D539DF20F7F680D704735B52C" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_InternalRevenueServiceIRSMember_1A05637D539DF20F7F680D704735B52C" xlink:to="lab_us-gaap_InternalRevenueServiceIRSMember_1A05637D539DF20F7F680D704735B52C" xlink:type="arc" />
    <link:label id="lab_us-gaap_LuxembourgInlandRevenueMember_4B2AFC87E2C1F3E64E570D7047357F2C_terseLabel_en-US" xlink:label="lab_us-gaap_LuxembourgInlandRevenueMember_4B2AFC87E2C1F3E64E570D7047357F2C" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Luxembourg</link:label>
    <link:label id="lab_us-gaap_LuxembourgInlandRevenueMember_4B2AFC87E2C1F3E64E570D7047357F2C_label_en-US" xlink:label="lab_us-gaap_LuxembourgInlandRevenueMember_4B2AFC87E2C1F3E64E570D7047357F2C" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Luxembourg Inland Revenue [Member]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_LuxembourgInlandRevenueMember" xlink:label="loc_us-gaap_LuxembourgInlandRevenueMember_4B2AFC87E2C1F3E64E570D7047357F2C" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LuxembourgInlandRevenueMember_4B2AFC87E2C1F3E64E570D7047357F2C" xlink:to="lab_us-gaap_LuxembourgInlandRevenueMember_4B2AFC87E2C1F3E64E570D7047357F2C" xlink:type="arc" />
    <link:label id="lab_arnc_FederalTaxServicesOfRussiaMember_AF2A9A3E6B089E632A9D0D70473539B8_terseLabel_en-US" xlink:label="lab_arnc_FederalTaxServicesOfRussiaMember_AF2A9A3E6B089E632A9D0D70473539B8" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Federal Tax Services of Russia</link:label>
    <link:label id="lab_arnc_FederalTaxServicesOfRussiaMember_AF2A9A3E6B089E632A9D0D70473539B8_label_en-US" xlink:label="lab_arnc_FederalTaxServicesOfRussiaMember_AF2A9A3E6B089E632A9D0D70473539B8" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Federal Tax Services Of Russia [Member]</link:label>
    <link:label id="lab_arnc_FederalTaxServicesOfRussiaMember_AF2A9A3E6B089E632A9D0D70473539B8_documentation_en-US" xlink:label="lab_arnc_FederalTaxServicesOfRussiaMember_AF2A9A3E6B089E632A9D0D70473539B8" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Federal tax services of Russia.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_FederalTaxServicesOfRussiaMember" xlink:label="loc_arnc_FederalTaxServicesOfRussiaMember_AF2A9A3E6B089E632A9D0D70473539B8" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_FederalTaxServicesOfRussiaMember_AF2A9A3E6B089E632A9D0D70473539B8" xlink:to="lab_arnc_FederalTaxServicesOfRussiaMember_AF2A9A3E6B089E632A9D0D70473539B8" xlink:type="arc" />
    <link:label id="lab_us-gaap_CanadaRevenueAgencyMember_F7A2D03509682FAB632F0D704735BC09_terseLabel_en-US" xlink:label="lab_us-gaap_CanadaRevenueAgencyMember_F7A2D03509682FAB632F0D704735BC09" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Canada Revenue Agency</link:label>
    <link:label id="lab_us-gaap_CanadaRevenueAgencyMember_F7A2D03509682FAB632F0D704735BC09_label_en-US" xlink:label="lab_us-gaap_CanadaRevenueAgencyMember_F7A2D03509682FAB632F0D704735BC09" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Canada Revenue Agency [Member]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_CanadaRevenueAgencyMember" xlink:label="loc_us-gaap_CanadaRevenueAgencyMember_F7A2D03509682FAB632F0D704735BC09" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CanadaRevenueAgencyMember_F7A2D03509682FAB632F0D704735BC09" xlink:to="lab_us-gaap_CanadaRevenueAgencyMember_F7A2D03509682FAB632F0D704735BC09" xlink:type="arc" />
    <link:label id="lab_us-gaap_AustralianTaxationOfficeMember_6C1908CFF90C0666DD290D704735D34D_terseLabel_en-US" xlink:label="lab_us-gaap_AustralianTaxationOfficeMember_6C1908CFF90C0666DD290D704735D34D" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Australia</link:label>
    <link:label id="lab_us-gaap_AustralianTaxationOfficeMember_6C1908CFF90C0666DD290D704735D34D_label_en-US" xlink:label="lab_us-gaap_AustralianTaxationOfficeMember_6C1908CFF90C0666DD290D704735D34D" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Australian Taxation Office [Member]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AustralianTaxationOfficeMember" xlink:label="loc_us-gaap_AustralianTaxationOfficeMember_6C1908CFF90C0666DD290D704735D34D" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AustralianTaxationOfficeMember_6C1908CFF90C0666DD290D704735D34D" xlink:to="lab_us-gaap_AustralianTaxationOfficeMember_6C1908CFF90C0666DD290D704735D34D" xlink:type="arc" />
    <link:label id="lab_us-gaap_TaxAuthoritySpainMember_0CCEF17294C3A8B5DEAA0D7047354F26_terseLabel_en-US" xlink:label="lab_us-gaap_TaxAuthoritySpainMember_0CCEF17294C3A8B5DEAA0D7047354F26" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Tax Authority, Spain</link:label>
    <link:label id="lab_us-gaap_TaxAuthoritySpainMember_0CCEF17294C3A8B5DEAA0D7047354F26_label_en-US" xlink:label="lab_us-gaap_TaxAuthoritySpainMember_0CCEF17294C3A8B5DEAA0D7047354F26" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Tax Authority, Spain [Member]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_TaxAuthoritySpainMember" xlink:label="loc_us-gaap_TaxAuthoritySpainMember_0CCEF17294C3A8B5DEAA0D7047354F26" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_TaxAuthoritySpainMember_0CCEF17294C3A8B5DEAA0D7047354F26" xlink:to="lab_us-gaap_TaxAuthoritySpainMember_0CCEF17294C3A8B5DEAA0D7047354F26" xlink:type="arc" />
    <link:label id="lab_us-gaap_IncomeTaxAuthorityAxis_BDBBB077F3277E4E39410D7047358E68_terseLabel_en-US" xlink:label="lab_us-gaap_IncomeTaxAuthorityAxis_BDBBB077F3277E4E39410D7047358E68" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Income Tax Authority [Axis]</link:label>
    <link:label id="lab_us-gaap_IncomeTaxAuthorityAxis_BDBBB077F3277E4E39410D7047358E68_label_en-US" xlink:label="lab_us-gaap_IncomeTaxAuthorityAxis_BDBBB077F3277E4E39410D7047358E68" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Income Tax Authority [Axis]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_IncomeTaxAuthorityAxis" xlink:label="loc_us-gaap_IncomeTaxAuthorityAxis_BDBBB077F3277E4E39410D7047358E68" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncomeTaxAuthorityAxis_BDBBB077F3277E4E39410D7047358E68" xlink:to="lab_us-gaap_IncomeTaxAuthorityAxis_BDBBB077F3277E4E39410D7047358E68" xlink:type="arc" />
    <link:label id="lab_us-gaap_IncomeTaxAuthorityDomain_A144E549728E1EC1337A0D7047359699_terseLabel_en-US" xlink:label="lab_us-gaap_IncomeTaxAuthorityDomain_A144E549728E1EC1337A0D7047359699" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Income Tax Authority [Domain]</link:label>
    <link:label id="lab_us-gaap_IncomeTaxAuthorityDomain_A144E549728E1EC1337A0D7047359699_label_en-US" xlink:label="lab_us-gaap_IncomeTaxAuthorityDomain_A144E549728E1EC1337A0D7047359699" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Income Tax Authority [Domain]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_IncomeTaxAuthorityDomain" xlink:label="loc_us-gaap_IncomeTaxAuthorityDomain_A144E549728E1EC1337A0D7047359699" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncomeTaxAuthorityDomain_A144E549728E1EC1337A0D7047359699" xlink:to="lab_us-gaap_IncomeTaxAuthorityDomain_A144E549728E1EC1337A0D7047359699" xlink:type="arc" />
    <link:label id="lab_us-gaap_ForeignCountryMember_16AD634428F72C5510D70D7047354789_terseLabel_en-US" xlink:label="lab_us-gaap_ForeignCountryMember_16AD634428F72C5510D70D7047354789" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Foreign Tax Authority</link:label>
    <link:label id="lab_us-gaap_ForeignCountryMember_16AD634428F72C5510D70D7047354789_label_en-US" xlink:label="lab_us-gaap_ForeignCountryMember_16AD634428F72C5510D70D7047354789" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Foreign Tax Authority [Member]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ForeignCountryMember" xlink:label="loc_us-gaap_ForeignCountryMember_16AD634428F72C5510D70D7047354789" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ForeignCountryMember_16AD634428F72C5510D70D7047354789" xlink:to="lab_us-gaap_ForeignCountryMember_16AD634428F72C5510D70D7047354789" xlink:type="arc" />
    <link:label id="lab_us-gaap_IncomeTaxContingencyLineItems_8E206D7B3306F027AA1B0D7047359A69_terseLabel_en-US" xlink:label="lab_us-gaap_IncomeTaxContingencyLineItems_8E206D7B3306F027AA1B0D7047359A69" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Income Tax Contingency [Line Items]</link:label>
    <link:label id="lab_us-gaap_IncomeTaxContingencyLineItems_8E206D7B3306F027AA1B0D7047359A69_label_en-US" xlink:label="lab_us-gaap_IncomeTaxContingencyLineItems_8E206D7B3306F027AA1B0D7047359A69" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Income Tax Contingency [Line Items]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_IncomeTaxContingencyLineItems" xlink:label="loc_us-gaap_IncomeTaxContingencyLineItems_8E206D7B3306F027AA1B0D7047359A69" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncomeTaxContingencyLineItems_8E206D7B3306F027AA1B0D7047359A69" xlink:to="lab_us-gaap_IncomeTaxContingencyLineItems_8E206D7B3306F027AA1B0D7047359A69" xlink:type="arc" />
    <link:label id="lab_arnc_UnamortizedTaxDeductibleGoodwillResultingFromIntercompanyStockSalesAndReorganizations_121336A3E7FAF29D10D90D7047352631_terseLabel_en-US" xlink:label="lab_arnc_UnamortizedTaxDeductibleGoodwillResultingFromIntercompanyStockSalesAndReorganizations_121336A3E7FAF29D10D90D7047352631" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Unamortized tax-deductible goodwill resulting from intercompany stock sales and reorganizations</link:label>
    <link:label id="lab_arnc_UnamortizedTaxDeductibleGoodwillResultingFromIntercompanyStockSalesAndReorganizations_121336A3E7FAF29D10D90D7047352631_label_en-US" xlink:label="lab_arnc_UnamortizedTaxDeductibleGoodwillResultingFromIntercompanyStockSalesAndReorganizations_121336A3E7FAF29D10D90D7047352631" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Unamortized Tax Deductible Goodwill Resulting From Intercompany Stock Sales And Reorganizations</link:label>
    <link:label id="lab_arnc_UnamortizedTaxDeductibleGoodwillResultingFromIntercompanyStockSalesAndReorganizations_121336A3E7FAF29D10D90D7047352631_documentation_en-US" xlink:label="lab_arnc_UnamortizedTaxDeductibleGoodwillResultingFromIntercompanyStockSalesAndReorganizations_121336A3E7FAF29D10D90D7047352631" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Unamortized tax deductible goodwill resulting from intercompany stock sales and reorganizations.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_UnamortizedTaxDeductibleGoodwillResultingFromIntercompanyStockSalesAndReorganizations" xlink:label="loc_arnc_UnamortizedTaxDeductibleGoodwillResultingFromIntercompanyStockSalesAndReorganizations_121336A3E7FAF29D10D90D7047352631" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_UnamortizedTaxDeductibleGoodwillResultingFromIntercompanyStockSalesAndReorganizations_121336A3E7FAF29D10D90D7047352631" xlink:to="lab_arnc_UnamortizedTaxDeductibleGoodwillResultingFromIntercompanyStockSalesAndReorganizations_121336A3E7FAF29D10D90D7047352631" xlink:type="arc" />
    <link:label id="lab_arnc_UnamortizedTaxDeductionRateOnGoodwill_BAC70BDBC0E2171F2FAF0D704735593A_terseLabel_en-US" xlink:label="lab_arnc_UnamortizedTaxDeductionRateOnGoodwill_BAC70BDBC0E2171F2FAF0D704735593A" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Unamortized tax-deduction rate on goodwill</link:label>
    <link:label id="lab_arnc_UnamortizedTaxDeductionRateOnGoodwill_BAC70BDBC0E2171F2FAF0D704735593A_label_en-US" xlink:label="lab_arnc_UnamortizedTaxDeductionRateOnGoodwill_BAC70BDBC0E2171F2FAF0D704735593A" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Unamortized Tax Deduction Rate On Goodwill</link:label>
    <link:label id="lab_arnc_UnamortizedTaxDeductionRateOnGoodwill_BAC70BDBC0E2171F2FAF0D704735593A_documentation_en-US" xlink:label="lab_arnc_UnamortizedTaxDeductionRateOnGoodwill_BAC70BDBC0E2171F2FAF0D704735593A" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Unamortized tax deduction rate on goodwill.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_UnamortizedTaxDeductionRateOnGoodwill" xlink:label="loc_arnc_UnamortizedTaxDeductionRateOnGoodwill_BAC70BDBC0E2171F2FAF0D704735593A" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_UnamortizedTaxDeductionRateOnGoodwill_BAC70BDBC0E2171F2FAF0D704735593A" xlink:to="lab_arnc_UnamortizedTaxDeductionRateOnGoodwill_BAC70BDBC0E2171F2FAF0D704735593A" xlink:type="arc" />
    <link:label id="lab_arnc_TaxCutsAndJobsActOf2017IncompleteAccountingChangeInTaxRateOneTimeTransitionTax_D00AC8BF169B8328DD480D704735CAD1_terseLabel_en-US" xlink:label="lab_arnc_TaxCutsAndJobsActOf2017IncompleteAccountingChangeInTaxRateOneTimeTransitionTax_D00AC8BF169B8328DD480D704735CAD1" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Tax cuts and jobs act of 2017, incomplete accounting, provisional income tax expense (benefit), one-time transition tax</link:label>
    <link:label id="lab_arnc_TaxCutsAndJobsActOf2017IncompleteAccountingChangeInTaxRateOneTimeTransitionTax_D00AC8BF169B8328DD480D704735CAD1_label_en-US" xlink:label="lab_arnc_TaxCutsAndJobsActOf2017IncompleteAccountingChangeInTaxRateOneTimeTransitionTax_D00AC8BF169B8328DD480D704735CAD1" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Tax Cuts And Jobs Act Of 2017, Incomplete Accounting, Change In Tax Rate, One-Time Transition Tax</link:label>
    <link:label id="lab_arnc_TaxCutsAndJobsActOf2017IncompleteAccountingChangeInTaxRateOneTimeTransitionTax_D00AC8BF169B8328DD480D704735CAD1_documentation_en-US" xlink:label="lab_arnc_TaxCutsAndJobsActOf2017IncompleteAccountingChangeInTaxRateOneTimeTransitionTax_D00AC8BF169B8328DD480D704735CAD1" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Tax Cuts And Jobs Act Of 2017, Incomplete Accounting, Change In Tax Rate, One-Time Transition Tax</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_TaxCutsAndJobsActOf2017IncompleteAccountingChangeInTaxRateOneTimeTransitionTax" xlink:label="loc_arnc_TaxCutsAndJobsActOf2017IncompleteAccountingChangeInTaxRateOneTimeTransitionTax_D00AC8BF169B8328DD480D704735CAD1" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_TaxCutsAndJobsActOf2017IncompleteAccountingChangeInTaxRateOneTimeTransitionTax_D00AC8BF169B8328DD480D704735CAD1" xlink:to="lab_arnc_TaxCutsAndJobsActOf2017IncompleteAccountingChangeInTaxRateOneTimeTransitionTax_D00AC8BF169B8328DD480D704735CAD1" xlink:type="arc" />
    <link:label id="lab_arnc_TaxCutsAndJobsActOf2017IncompleteAccountingChangeInTaxRateValuationAllowance_FA5040FFF105246AB7950D7047356FDB_terseLabel_en-US" xlink:label="lab_arnc_TaxCutsAndJobsActOf2017IncompleteAccountingChangeInTaxRateValuationAllowance_FA5040FFF105246AB7950D7047356FDB" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Tax cuts and jobs act of 2017, incomplete accounting, provisional income tax expense (benefit), charge to record valuation allowance on U.S. foreign tax credits</link:label>
    <link:label id="lab_arnc_TaxCutsAndJobsActOf2017IncompleteAccountingChangeInTaxRateValuationAllowance_FA5040FFF105246AB7950D7047356FDB_label_en-US" xlink:label="lab_arnc_TaxCutsAndJobsActOf2017IncompleteAccountingChangeInTaxRateValuationAllowance_FA5040FFF105246AB7950D7047356FDB" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Tax Cuts And Jobs Act Of 2017, Incomplete Accounting, Change In Tax Rate, Valuation Allowance</link:label>
    <link:label id="lab_arnc_TaxCutsAndJobsActOf2017IncompleteAccountingChangeInTaxRateValuationAllowance_FA5040FFF105246AB7950D7047356FDB_documentation_en-US" xlink:label="lab_arnc_TaxCutsAndJobsActOf2017IncompleteAccountingChangeInTaxRateValuationAllowance_FA5040FFF105246AB7950D7047356FDB" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Tax Cuts And Jobs Act Of 2017, Incomplete Accounting, Change in Tax Rate, Valuation Allowance</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_TaxCutsAndJobsActOf2017IncompleteAccountingChangeInTaxRateValuationAllowance" xlink:label="loc_arnc_TaxCutsAndJobsActOf2017IncompleteAccountingChangeInTaxRateValuationAllowance_FA5040FFF105246AB7950D7047356FDB" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_TaxCutsAndJobsActOf2017IncompleteAccountingChangeInTaxRateValuationAllowance_FA5040FFF105246AB7950D7047356FDB" xlink:to="lab_arnc_TaxCutsAndJobsActOf2017IncompleteAccountingChangeInTaxRateValuationAllowance_FA5040FFF105246AB7950D7047356FDB" xlink:type="arc" />
    <link:label id="lab_arnc_PercentageOfTemporaryTaxDifferencesThatReverseWithinCarryforwardPeriod_C8907055F531A9EDA9F10D7047354CC5_terseLabel_en-US" xlink:label="lab_arnc_PercentageOfTemporaryTaxDifferencesThatReverseWithinCarryforwardPeriod_C8907055F531A9EDA9F10D7047354CC5" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Percentage of temporary tax differences that reverse within the carryforward period</link:label>
    <link:label id="lab_arnc_PercentageOfTemporaryTaxDifferencesThatReverseWithinCarryforwardPeriod_C8907055F531A9EDA9F10D7047354CC5_label_en-US" xlink:label="lab_arnc_PercentageOfTemporaryTaxDifferencesThatReverseWithinCarryforwardPeriod_C8907055F531A9EDA9F10D7047354CC5" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Percentage Of Temporary Tax Differences That Reverse Within Carryforward Period</link:label>
    <link:label id="lab_arnc_PercentageOfTemporaryTaxDifferencesThatReverseWithinCarryforwardPeriod_C8907055F531A9EDA9F10D7047354CC5_documentation_en-US" xlink:label="lab_arnc_PercentageOfTemporaryTaxDifferencesThatReverseWithinCarryforwardPeriod_C8907055F531A9EDA9F10D7047354CC5" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Percentage of temporary tax differences that reverse within the carryforward period.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_PercentageOfTemporaryTaxDifferencesThatReverseWithinCarryforwardPeriod" xlink:label="loc_arnc_PercentageOfTemporaryTaxDifferencesThatReverseWithinCarryforwardPeriod_C8907055F531A9EDA9F10D7047354CC5" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_PercentageOfTemporaryTaxDifferencesThatReverseWithinCarryforwardPeriod_C8907055F531A9EDA9F10D7047354CC5" xlink:to="lab_arnc_PercentageOfTemporaryTaxDifferencesThatReverseWithinCarryforwardPeriod_C8907055F531A9EDA9F10D7047354CC5" xlink:type="arc" />
    <link:label id="lab_arnc_PercentageOfDeferredTaxAssetExclusiveOfReversingTemporaryDifferences_64D7B795A87AAD4669910D7047351B55_terseLabel_en-US" xlink:label="lab_arnc_PercentageOfDeferredTaxAssetExclusiveOfReversingTemporaryDifferences_64D7B795A87AAD4669910D7047351B55" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Percentage of deferred tax asset exclusive of reversing temporary differences</link:label>
    <link:label id="lab_arnc_PercentageOfDeferredTaxAssetExclusiveOfReversingTemporaryDifferences_64D7B795A87AAD4669910D7047351B55_label_en-US" xlink:label="lab_arnc_PercentageOfDeferredTaxAssetExclusiveOfReversingTemporaryDifferences_64D7B795A87AAD4669910D7047351B55" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Percentage Of Deferred Tax Asset Exclusive Of Reversing Temporary Differences</link:label>
    <link:label id="lab_arnc_PercentageOfDeferredTaxAssetExclusiveOfReversingTemporaryDifferences_64D7B795A87AAD4669910D7047351B55_documentation_en-US" xlink:label="lab_arnc_PercentageOfDeferredTaxAssetExclusiveOfReversingTemporaryDifferences_64D7B795A87AAD4669910D7047351B55" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Percentage of deferred tax asset exclusive of reversing temporary differences.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_PercentageOfDeferredTaxAssetExclusiveOfReversingTemporaryDifferences" xlink:label="loc_arnc_PercentageOfDeferredTaxAssetExclusiveOfReversingTemporaryDifferences_64D7B795A87AAD4669910D7047351B55" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_PercentageOfDeferredTaxAssetExclusiveOfReversingTemporaryDifferences_64D7B795A87AAD4669910D7047351B55" xlink:to="lab_arnc_PercentageOfDeferredTaxAssetExclusiveOfReversingTemporaryDifferences_64D7B795A87AAD4669910D7047351B55" xlink:type="arc" />
    <link:label id="lab_arnc_DeferredTaxAssetIncreaseDecreaseAmountForeignTaxCredit_83886B6849F3D510021C0D704735E4DC_terseLabel_en-US" xlink:label="lab_arnc_DeferredTaxAssetIncreaseDecreaseAmountForeignTaxCredit_83886B6849F3D510021C0D704735E4DC" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Deferred tax asset, increase (decrease), amount, foreign tax credit</link:label>
    <link:label id="lab_arnc_DeferredTaxAssetIncreaseDecreaseAmountForeignTaxCredit_83886B6849F3D510021C0D704735E4DC_label_en-US" xlink:label="lab_arnc_DeferredTaxAssetIncreaseDecreaseAmountForeignTaxCredit_83886B6849F3D510021C0D704735E4DC" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Deferred Tax Asset, Increase (Decrease), Amount, Foreign Tax Credit</link:label>
    <link:label id="lab_arnc_DeferredTaxAssetIncreaseDecreaseAmountForeignTaxCredit_83886B6849F3D510021C0D704735E4DC_documentation_en-US" xlink:label="lab_arnc_DeferredTaxAssetIncreaseDecreaseAmountForeignTaxCredit_83886B6849F3D510021C0D704735E4DC" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Deferred Tax Asset, Increase (Decrease), Amount, Foreign Tax Credit</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_DeferredTaxAssetIncreaseDecreaseAmountForeignTaxCredit" xlink:label="loc_arnc_DeferredTaxAssetIncreaseDecreaseAmountForeignTaxCredit_83886B6849F3D510021C0D704735E4DC" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_DeferredTaxAssetIncreaseDecreaseAmountForeignTaxCredit_83886B6849F3D510021C0D704735E4DC" xlink:to="lab_arnc_DeferredTaxAssetIncreaseDecreaseAmountForeignTaxCredit_83886B6849F3D510021C0D704735E4DC" xlink:type="arc" />
    <link:label id="lab_arnc_DeferredTaxAssetsTaxCreditCarryforwardsForeignExpiredDuringPeriod_07A6997A44D6972E75230D7047350318_terseLabel_en-US" xlink:label="lab_arnc_DeferredTaxAssetsTaxCreditCarryforwardsForeignExpiredDuringPeriod_07A6997A44D6972E75230D7047350318" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Deferred tax assets, tax credit carryforwards, foreign, expired during period</link:label>
    <link:label id="lab_arnc_DeferredTaxAssetsTaxCreditCarryforwardsForeignExpiredDuringPeriod_07A6997A44D6972E75230D7047350318_label_en-US" xlink:label="lab_arnc_DeferredTaxAssetsTaxCreditCarryforwardsForeignExpiredDuringPeriod_07A6997A44D6972E75230D7047350318" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Deferred Tax Assets, Tax Credit Carryforwards, Foreign, Expired During Period</link:label>
    <link:label id="lab_arnc_DeferredTaxAssetsTaxCreditCarryforwardsForeignExpiredDuringPeriod_07A6997A44D6972E75230D7047350318_documentation_en-US" xlink:label="lab_arnc_DeferredTaxAssetsTaxCreditCarryforwardsForeignExpiredDuringPeriod_07A6997A44D6972E75230D7047350318" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Deferred Tax Assets, Tax Credit Carryforwards, Foreign, Expired During Period</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_DeferredTaxAssetsTaxCreditCarryforwardsForeignExpiredDuringPeriod" xlink:label="loc_arnc_DeferredTaxAssetsTaxCreditCarryforwardsForeignExpiredDuringPeriod_07A6997A44D6972E75230D7047350318" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_DeferredTaxAssetsTaxCreditCarryforwardsForeignExpiredDuringPeriod_07A6997A44D6972E75230D7047350318" xlink:to="lab_arnc_DeferredTaxAssetsTaxCreditCarryforwardsForeignExpiredDuringPeriod_07A6997A44D6972E75230D7047350318" xlink:type="arc" />
    <link:label id="lab_arnc_DeferredTaxAssetsValuationAllowanceForeignTaxCredit_3902F8E2962C60F94CB00D704735010B_terseLabel_en-US" xlink:label="lab_arnc_DeferredTaxAssetsValuationAllowanceForeignTaxCredit_3902F8E2962C60F94CB00D704735010B" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Deferred tax assets, valuation allowance, foreign tax credit</link:label>
    <link:label id="lab_arnc_DeferredTaxAssetsValuationAllowanceForeignTaxCredit_3902F8E2962C60F94CB00D704735010B_label_en-US" xlink:label="lab_arnc_DeferredTaxAssetsValuationAllowanceForeignTaxCredit_3902F8E2962C60F94CB00D704735010B" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Deferred Tax Assets, Valuation Allowance, Foreign Tax Credit</link:label>
    <link:label id="lab_arnc_DeferredTaxAssetsValuationAllowanceForeignTaxCredit_3902F8E2962C60F94CB00D704735010B_documentation_en-US" xlink:label="lab_arnc_DeferredTaxAssetsValuationAllowanceForeignTaxCredit_3902F8E2962C60F94CB00D704735010B" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Deferred Tax Assets, Valuation Allowance, Foreign Tax Credit</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_DeferredTaxAssetsValuationAllowanceForeignTaxCredit" xlink:label="loc_arnc_DeferredTaxAssetsValuationAllowanceForeignTaxCredit_3902F8E2962C60F94CB00D704735010B" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_DeferredTaxAssetsValuationAllowanceForeignTaxCredit_3902F8E2962C60F94CB00D704735010B" xlink:to="lab_arnc_DeferredTaxAssetsValuationAllowanceForeignTaxCredit_3902F8E2962C60F94CB00D704735010B" xlink:type="arc" />
    <link:label id="lab_us-gaap_TaxCreditCarryforwardValuationAllowance_F8CF4CB3D1EBDA7969C00D70473541D0_terseLabel_en-US" xlink:label="lab_us-gaap_TaxCreditCarryforwardValuationAllowance_F8CF4CB3D1EBDA7969C00D70473541D0" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Valuation allowance, amount released</link:label>
    <link:label id="lab_us-gaap_TaxCreditCarryforwardValuationAllowance_F8CF4CB3D1EBDA7969C00D70473541D0_label_en-US" xlink:label="lab_us-gaap_TaxCreditCarryforwardValuationAllowance_F8CF4CB3D1EBDA7969C00D70473541D0" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Tax Credit Carryforward, Valuation Allowance</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_TaxCreditCarryforwardValuationAllowance" xlink:label="loc_us-gaap_TaxCreditCarryforwardValuationAllowance_F8CF4CB3D1EBDA7969C00D70473541D0" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_TaxCreditCarryforwardValuationAllowance_F8CF4CB3D1EBDA7969C00D70473541D0" xlink:to="lab_us-gaap_TaxCreditCarryforwardValuationAllowance_F8CF4CB3D1EBDA7969C00D70473541D0" xlink:type="arc" />
    <link:label id="lab_us-gaap_DeferredTaxAssetsValuationAllowance_FEA039C14D48244331660D704735BA28_terseLabel_en-US" xlink:label="lab_us-gaap_DeferredTaxAssetsValuationAllowance_FEA039C14D48244331660D704735BA28" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Valuation allowance</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DeferredTaxAssetsValuationAllowance" xlink:label="loc_us-gaap_DeferredTaxAssetsValuationAllowance_FEA039C14D48244331660D704735BA28" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DeferredTaxAssetsValuationAllowance_FEA039C14D48244331660D704735BA28" xlink:to="lab_us-gaap_DeferredTaxAssetsValuationAllowance_FEA039C14D48244331660D704735BA28" xlink:type="arc" />
    <link:label id="lab_us-gaap_ValuationAllowanceDeferredTaxAssetChangeInAmount_112CF7D3E03A6B65CB3A0D704735D248_verboseLabel_en-US" xlink:label="lab_us-gaap_ValuationAllowanceDeferredTaxAssetChangeInAmount_112CF7D3E03A6B65CB3A0D704735D248" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Increase (decrease) to valuation allowance</link:label>
    <link:label id="lab_us-gaap_ValuationAllowanceDeferredTaxAssetChangeInAmount_112CF7D3E03A6B65CB3A0D704735D248_label_en-US" xlink:label="lab_us-gaap_ValuationAllowanceDeferredTaxAssetChangeInAmount_112CF7D3E03A6B65CB3A0D704735D248" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Valuation Allowance, Deferred Tax Asset, Increase (Decrease), Amount</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ValuationAllowanceDeferredTaxAssetChangeInAmount" xlink:label="loc_us-gaap_ValuationAllowanceDeferredTaxAssetChangeInAmount_112CF7D3E03A6B65CB3A0D704735D248" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ValuationAllowanceDeferredTaxAssetChangeInAmount_112CF7D3E03A6B65CB3A0D704735D248" xlink:to="lab_us-gaap_ValuationAllowanceDeferredTaxAssetChangeInAmount_112CF7D3E03A6B65CB3A0D704735D248" xlink:type="arc" />
    <link:label id="lab_arnc_DeferredTaxAssetIncreaseDecreaseAmountExpirationOfLossReversal_EDEF36799FEB06D78C750D7047355A13_terseLabel_en-US" xlink:label="lab_arnc_DeferredTaxAssetIncreaseDecreaseAmountExpirationOfLossReversal_EDEF36799FEB06D78C750D7047355A13" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Valuation allowance, changes due to losses no longer supported by temporary differences</link:label>
    <link:label id="lab_arnc_DeferredTaxAssetIncreaseDecreaseAmountExpirationOfLossReversal_EDEF36799FEB06D78C750D7047355A13_label_en-US" xlink:label="lab_arnc_DeferredTaxAssetIncreaseDecreaseAmountExpirationOfLossReversal_EDEF36799FEB06D78C750D7047355A13" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Deferred Tax Asset, Increase (Decrease), Amount, Expiration Of Loss Reversal</link:label>
    <link:label id="lab_arnc_DeferredTaxAssetIncreaseDecreaseAmountExpirationOfLossReversal_EDEF36799FEB06D78C750D7047355A13_documentation_en-US" xlink:label="lab_arnc_DeferredTaxAssetIncreaseDecreaseAmountExpirationOfLossReversal_EDEF36799FEB06D78C750D7047355A13" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Deferred Tax Asset, Increase (Decrease), Amount, Expiration Of Loss Reversal</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_DeferredTaxAssetIncreaseDecreaseAmountExpirationOfLossReversal" xlink:label="loc_arnc_DeferredTaxAssetIncreaseDecreaseAmountExpirationOfLossReversal_EDEF36799FEB06D78C750D7047355A13" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_DeferredTaxAssetIncreaseDecreaseAmountExpirationOfLossReversal_EDEF36799FEB06D78C750D7047355A13" xlink:to="lab_arnc_DeferredTaxAssetIncreaseDecreaseAmountExpirationOfLossReversal_EDEF36799FEB06D78C750D7047355A13" xlink:type="arc" />
    <link:label id="lab_arnc_DiscreteIncomeTaxExpense_7BF438B027DCCB0BC8B60D70473538AC_verboseLabel_en-US" xlink:label="lab_arnc_DiscreteIncomeTaxExpense_7BF438B027DCCB0BC8B60D70473538AC" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Discrete income tax charge for valuation allowances</link:label>
    <link:label id="lab_arnc_DiscreteIncomeTaxExpense_7BF438B027DCCB0BC8B60D70473538AC_label_en-US" xlink:label="lab_arnc_DiscreteIncomeTaxExpense_7BF438B027DCCB0BC8B60D70473538AC" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Discrete Income Tax Expense</link:label>
    <link:label id="lab_arnc_DiscreteIncomeTaxExpense_7BF438B027DCCB0BC8B60D70473538AC_documentation_en-US" xlink:label="lab_arnc_DiscreteIncomeTaxExpense_7BF438B027DCCB0BC8B60D70473538AC" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Discrete Income Tax Expense</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_DiscreteIncomeTaxExpense" xlink:label="loc_arnc_DiscreteIncomeTaxExpense_7BF438B027DCCB0BC8B60D70473538AC" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_DiscreteIncomeTaxExpense_7BF438B027DCCB0BC8B60D70473538AC" xlink:to="lab_arnc_DiscreteIncomeTaxExpense_7BF438B027DCCB0BC8B60D70473538AC" xlink:type="arc" />
    <link:label id="lab_us-gaap_DeferredTaxAssetsLiabilitiesNet_7246DDF5236AC9FC94E50D704735D34F_verboseLabel_en-US" xlink:label="lab_us-gaap_DeferredTaxAssetsLiabilitiesNet_7246DDF5236AC9FC94E50D704735D34F" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Net deferred tax assets</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DeferredTaxAssetsLiabilitiesNet" xlink:label="loc_us-gaap_DeferredTaxAssetsLiabilitiesNet_7246DDF5236AC9FC94E50D704735D34F" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DeferredTaxAssetsLiabilitiesNet_7246DDF5236AC9FC94E50D704735D34F" xlink:to="lab_us-gaap_DeferredTaxAssetsLiabilitiesNet_7246DDF5236AC9FC94E50D704735D34F" xlink:type="arc" />
    <link:label id="lab_us-gaap_DeferredTaxAssetsOther_850F8D6959B561056B5C0D704735730A_negatedLabel_en-US" xlink:label="lab_us-gaap_DeferredTaxAssetsOther_850F8D6959B561056B5C0D704735730A" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xml:lang="en-US">Net deferred tax assets other</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DeferredTaxAssetsOther" xlink:label="loc_us-gaap_DeferredTaxAssetsOther_850F8D6959B561056B5C0D704735730A" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DeferredTaxAssetsOther_850F8D6959B561056B5C0D704735730A" xlink:to="lab_us-gaap_DeferredTaxAssetsOther_850F8D6959B561056B5C0D704735730A" xlink:type="arc" />
    <link:label id="lab_arnc_PercentageOfEffectOfUnrecognizedTaxBenefitIfRecorded_BEC91F2EFDB1216ABC4A0D704735F7A5_terseLabel_en-US" xlink:label="lab_arnc_PercentageOfEffectOfUnrecognizedTaxBenefitIfRecorded_BEC91F2EFDB1216ABC4A0D704735F7A5" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Percentage of the effect of unrecognized tax benefit, if recorded</link:label>
    <link:label id="lab_arnc_PercentageOfEffectOfUnrecognizedTaxBenefitIfRecorded_BEC91F2EFDB1216ABC4A0D704735F7A5_label_en-US" xlink:label="lab_arnc_PercentageOfEffectOfUnrecognizedTaxBenefitIfRecorded_BEC91F2EFDB1216ABC4A0D704735F7A5" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Percentage Of Effect Of Unrecognized Tax Benefit If Recorded</link:label>
    <link:label id="lab_arnc_PercentageOfEffectOfUnrecognizedTaxBenefitIfRecorded_BEC91F2EFDB1216ABC4A0D704735F7A5_documentation_en-US" xlink:label="lab_arnc_PercentageOfEffectOfUnrecognizedTaxBenefitIfRecorded_BEC91F2EFDB1216ABC4A0D704735F7A5" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Percentage of the effect of unrecognized tax benefit, if recorded.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_PercentageOfEffectOfUnrecognizedTaxBenefitIfRecorded" xlink:label="loc_arnc_PercentageOfEffectOfUnrecognizedTaxBenefitIfRecorded_BEC91F2EFDB1216ABC4A0D704735F7A5" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_PercentageOfEffectOfUnrecognizedTaxBenefitIfRecorded_BEC91F2EFDB1216ABC4A0D704735F7A5" xlink:to="lab_arnc_PercentageOfEffectOfUnrecognizedTaxBenefitIfRecorded_BEC91F2EFDB1216ABC4A0D704735F7A5" xlink:type="arc" />
    <link:label id="lab_us-gaap_IncomeTaxExaminationPenaltiesAndInterestExpense_FB9F641C978B493AECEF0D704735C124_terseLabel_en-US" xlink:label="lab_us-gaap_IncomeTaxExaminationPenaltiesAndInterestExpense_FB9F641C978B493AECEF0D704735C124" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Interest or penalties recognized</link:label>
    <link:label id="lab_us-gaap_IncomeTaxExaminationPenaltiesAndInterestExpense_FB9F641C978B493AECEF0D704735C124_label_en-US" xlink:label="lab_us-gaap_IncomeTaxExaminationPenaltiesAndInterestExpense_FB9F641C978B493AECEF0D704735C124" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Income Tax Examination, Penalties and Interest Expense</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_IncomeTaxExaminationPenaltiesAndInterestExpense" xlink:label="loc_us-gaap_IncomeTaxExaminationPenaltiesAndInterestExpense_FB9F641C978B493AECEF0D704735C124" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncomeTaxExaminationPenaltiesAndInterestExpense_FB9F641C978B493AECEF0D704735C124" xlink:to="lab_us-gaap_IncomeTaxExaminationPenaltiesAndInterestExpense_FB9F641C978B493AECEF0D704735C124" xlink:type="arc" />
    <link:label id="lab_arnc_IncomeTaxExpensePaymentOfInterestAndPenalties_F55757C494F59CC440F00D70473550A9_terseLabel_en-US" xlink:label="lab_arnc_IncomeTaxExpensePaymentOfInterestAndPenalties_F55757C494F59CC440F00D70473550A9" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Income related to accrued interest and penalties</link:label>
    <link:label id="lab_arnc_IncomeTaxExpensePaymentOfInterestAndPenalties_F55757C494F59CC440F00D70473550A9_label_en-US" xlink:label="lab_arnc_IncomeTaxExpensePaymentOfInterestAndPenalties_F55757C494F59CC440F00D70473550A9" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Income Tax Expense Payment Of Interest And Penalties</link:label>
    <link:label id="lab_arnc_IncomeTaxExpensePaymentOfInterestAndPenalties_F55757C494F59CC440F00D70473550A9_documentation_en-US" xlink:label="lab_arnc_IncomeTaxExpensePaymentOfInterestAndPenalties_F55757C494F59CC440F00D70473550A9" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Income tax expense, payment of interest and penalties.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_IncomeTaxExpensePaymentOfInterestAndPenalties" xlink:label="loc_arnc_IncomeTaxExpensePaymentOfInterestAndPenalties_F55757C494F59CC440F00D70473550A9" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_IncomeTaxExpensePaymentOfInterestAndPenalties_F55757C494F59CC440F00D70473550A9" xlink:to="lab_arnc_IncomeTaxExpensePaymentOfInterestAndPenalties_F55757C494F59CC440F00D70473550A9" xlink:type="arc" />
    <link:label id="lab_us-gaap_UnrecognizedTaxBenefitsIncomeTaxPenaltiesAccrued_1E4B7197291D558A7CAB0D704735EFB2_terseLabel_en-US" xlink:label="lab_us-gaap_UnrecognizedTaxBenefitsIncomeTaxPenaltiesAccrued_1E4B7197291D558A7CAB0D704735EFB2" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Amount accrued for payment of interest and penalties</link:label>
    <link:label id="lab_us-gaap_UnrecognizedTaxBenefitsIncomeTaxPenaltiesAccrued_1E4B7197291D558A7CAB0D704735EFB2_label_en-US" xlink:label="lab_us-gaap_UnrecognizedTaxBenefitsIncomeTaxPenaltiesAccrued_1E4B7197291D558A7CAB0D704735EFB2" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Unrecognized Tax Benefits, Income Tax Penalties Accrued</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_UnrecognizedTaxBenefitsIncomeTaxPenaltiesAccrued" xlink:label="loc_us-gaap_UnrecognizedTaxBenefitsIncomeTaxPenaltiesAccrued_1E4B7197291D558A7CAB0D704735EFB2" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_UnrecognizedTaxBenefitsIncomeTaxPenaltiesAccrued_1E4B7197291D558A7CAB0D704735EFB2" xlink:to="lab_us-gaap_UnrecognizedTaxBenefitsIncomeTaxPenaltiesAccrued_1E4B7197291D558A7CAB0D704735EFB2" xlink:type="arc" />
    <link:label id="lab_us-gaap_EmployeeServiceShareBasedCompensationTaxBenefitFromExerciseOfStockOptions_23932D85DD9E03C7489C0DBA03DB222B_terseLabel_en-US" xlink:label="lab_us-gaap_EmployeeServiceShareBasedCompensationTaxBenefitFromExerciseOfStockOptions_23932D85DD9E03C7489C0DBA03DB222B" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Employee Service Share-based Compensation, Tax Benefit from Exercise of Stock Options</link:label>
    <link:label id="lab_us-gaap_EmployeeServiceShareBasedCompensationTaxBenefitFromExerciseOfStockOptions_23932D85DD9E03C7489C0DBA03DB222B_label_en-US" xlink:label="lab_us-gaap_EmployeeServiceShareBasedCompensationTaxBenefitFromExerciseOfStockOptions_23932D85DD9E03C7489C0DBA03DB222B" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Employee Service Share-based Compensation, Tax Benefit from Exercise of Stock Options</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_EmployeeServiceShareBasedCompensationTaxBenefitFromExerciseOfStockOptions" xlink:label="loc_us-gaap_EmployeeServiceShareBasedCompensationTaxBenefitFromExerciseOfStockOptions_23932D85DD9E03C7489C0DBA03DB222B" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_EmployeeServiceShareBasedCompensationTaxBenefitFromExerciseOfStockOptions_23932D85DD9E03C7489C0DBA03DB222B" xlink:to="lab_us-gaap_EmployeeServiceShareBasedCompensationTaxBenefitFromExerciseOfStockOptions_23932D85DD9E03C7489C0DBA03DB222B" xlink:type="arc" />
    <link:label id="lab_us-gaap_ValuationAllowanceTable_ACC4D4A4A0C4ED0634600D704D6B665E_terseLabel_en-US" xlink:label="lab_us-gaap_ValuationAllowanceTable_ACC4D4A4A0C4ED0634600D704D6B665E" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Valuation Allowance [Table]</link:label>
    <link:label id="lab_us-gaap_ValuationAllowanceTable_ACC4D4A4A0C4ED0634600D704D6B665E_label_en-US" xlink:label="lab_us-gaap_ValuationAllowanceTable_ACC4D4A4A0C4ED0634600D704D6B665E" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Valuation Allowance [Table]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ValuationAllowanceTable" xlink:label="loc_us-gaap_ValuationAllowanceTable_ACC4D4A4A0C4ED0634600D704D6B665E" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ValuationAllowanceTable_ACC4D4A4A0C4ED0634600D704D6B665E" xlink:to="lab_us-gaap_ValuationAllowanceTable_ACC4D4A4A0C4ED0634600D704D6B665E" xlink:type="arc" />
    <link:label id="lab_us-gaap_ValuationAllowanceLineItems_4589C26C0C1EC58AD12D0D704D6BF064_terseLabel_en-US" xlink:label="lab_us-gaap_ValuationAllowanceLineItems_4589C26C0C1EC58AD12D0D704D6BF064" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Valuation Allowance [Line Items]</link:label>
    <link:label id="lab_us-gaap_ValuationAllowanceLineItems_4589C26C0C1EC58AD12D0D704D6BF064_label_en-US" xlink:label="lab_us-gaap_ValuationAllowanceLineItems_4589C26C0C1EC58AD12D0D704D6BF064" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Valuation Allowance [Line Items]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ValuationAllowanceLineItems" xlink:label="loc_us-gaap_ValuationAllowanceLineItems_4589C26C0C1EC58AD12D0D704D6BF064" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ValuationAllowanceLineItems_4589C26C0C1EC58AD12D0D704D6BF064" xlink:to="lab_us-gaap_ValuationAllowanceLineItems_4589C26C0C1EC58AD12D0D704D6BF064" xlink:type="arc" />
    <link:label id="lab_us-gaap_DeferredTaxAssetsValuationAllowance_EA4537C12C1F553C09140D704D6BAF10_periodStartLabel_en-US" xlink:label="lab_us-gaap_DeferredTaxAssetsValuationAllowance_EA4537C12C1F553C09140D704D6BAF10" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel" xlink:type="resource" xml:lang="en-US">Balance at beginning of year</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DeferredTaxAssetsValuationAllowance" xlink:label="loc_us-gaap_DeferredTaxAssetsValuationAllowance_EA4537C12C1F553C09140D704D6BAF10" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DeferredTaxAssetsValuationAllowance_EA4537C12C1F553C09140D704D6BAF10" xlink:to="lab_us-gaap_DeferredTaxAssetsValuationAllowance_EA4537C12C1F553C09140D704D6BAF10" xlink:type="arc" />
    <link:label id="lab_us-gaap_ValuationAllowanceDeferredTaxAssetChangeInAmount_D49A15ACACCF9530F0250D704D6B9236_terseLabel_en-US" xlink:label="lab_us-gaap_ValuationAllowanceDeferredTaxAssetChangeInAmount_D49A15ACACCF9530F0250D704D6B9236" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Increase to allowance</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ValuationAllowanceDeferredTaxAssetChangeInAmount" xlink:label="loc_us-gaap_ValuationAllowanceDeferredTaxAssetChangeInAmount_D49A15ACACCF9530F0250D704D6B9236" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ValuationAllowanceDeferredTaxAssetChangeInAmount_D49A15ACACCF9530F0250D704D6B9236" xlink:to="lab_us-gaap_ValuationAllowanceDeferredTaxAssetChangeInAmount_D49A15ACACCF9530F0250D704D6B9236" xlink:type="arc" />
    <link:label id="lab_arnc_DeferredTaxAssetsValuationReleaseOfAllowance_3519D5767177854ADDC40D704D6B01D1_negatedLabel_en-US" xlink:label="lab_arnc_DeferredTaxAssetsValuationReleaseOfAllowance_3519D5767177854ADDC40D704D6B01D1" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xml:lang="en-US">Release of allowance</link:label>
    <link:label id="lab_arnc_DeferredTaxAssetsValuationReleaseOfAllowance_3519D5767177854ADDC40D704D6B01D1_label_en-US" xlink:label="lab_arnc_DeferredTaxAssetsValuationReleaseOfAllowance_3519D5767177854ADDC40D704D6B01D1" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Deferred Tax Assets Valuation Release Of Allowance</link:label>
    <link:label id="lab_arnc_DeferredTaxAssetsValuationReleaseOfAllowance_3519D5767177854ADDC40D704D6B01D1_documentation_en-US" xlink:label="lab_arnc_DeferredTaxAssetsValuationReleaseOfAllowance_3519D5767177854ADDC40D704D6B01D1" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Deferred tax assets valuation release of allowance.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_DeferredTaxAssetsValuationReleaseOfAllowance" xlink:label="loc_arnc_DeferredTaxAssetsValuationReleaseOfAllowance_3519D5767177854ADDC40D704D6B01D1" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_DeferredTaxAssetsValuationReleaseOfAllowance_3519D5767177854ADDC40D704D6B01D1" xlink:to="lab_arnc_DeferredTaxAssetsValuationReleaseOfAllowance_3519D5767177854ADDC40D704D6B01D1" xlink:type="arc" />
    <link:label id="lab_arnc_DeferredTaxAssetsValuationAcquisitionsDivestitures_A61FCE7281366A0C924C0D704D6B5B4F_negatedLabel_en-US" xlink:label="lab_arnc_DeferredTaxAssetsValuationAcquisitionsDivestitures_A61FCE7281366A0C924C0D704D6B5B4F" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xml:lang="en-US">Acquisitions and divestitures (F)</link:label>
    <link:label id="lab_arnc_DeferredTaxAssetsValuationAcquisitionsDivestitures_A61FCE7281366A0C924C0D704D6B5B4F_label_en-US" xlink:label="lab_arnc_DeferredTaxAssetsValuationAcquisitionsDivestitures_A61FCE7281366A0C924C0D704D6B5B4F" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Deferred Tax Assets Valuation Acquisitions Divestitures</link:label>
    <link:label id="lab_arnc_DeferredTaxAssetsValuationAcquisitionsDivestitures_A61FCE7281366A0C924C0D704D6B5B4F_documentation_en-US" xlink:label="lab_arnc_DeferredTaxAssetsValuationAcquisitionsDivestitures_A61FCE7281366A0C924C0D704D6B5B4F" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Deferred tax assets valuation acquisitions divestitures.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_DeferredTaxAssetsValuationAcquisitionsDivestitures" xlink:label="loc_arnc_DeferredTaxAssetsValuationAcquisitionsDivestitures_A61FCE7281366A0C924C0D704D6B5B4F" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_DeferredTaxAssetsValuationAcquisitionsDivestitures_A61FCE7281366A0C924C0D704D6B5B4F" xlink:to="lab_arnc_DeferredTaxAssetsValuationAcquisitionsDivestitures_A61FCE7281366A0C924C0D704D6B5B4F" xlink:type="arc" />
    <link:label id="lab_arnc_ChangeInValuationAllowanceRelatedToDeferredStateIncomeTaxes_DB06A90A93F3CED9FBF80D704D6B5930_terseLabel_en-US" xlink:label="lab_arnc_ChangeInValuationAllowanceRelatedToDeferredStateIncomeTaxes_DB06A90A93F3CED9FBF80D704D6B5930" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Tax apportionment, tax rate and tax law changes</link:label>
    <link:label id="lab_arnc_ChangeInValuationAllowanceRelatedToDeferredStateIncomeTaxes_DB06A90A93F3CED9FBF80D704D6B5930_label_en-US" xlink:label="lab_arnc_ChangeInValuationAllowanceRelatedToDeferredStateIncomeTaxes_DB06A90A93F3CED9FBF80D704D6B5930" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Change In Valuation Allowance Related To Deferred State Income Taxes</link:label>
    <link:label id="lab_arnc_ChangeInValuationAllowanceRelatedToDeferredStateIncomeTaxes_DB06A90A93F3CED9FBF80D704D6B5930_documentation_en-US" xlink:label="lab_arnc_ChangeInValuationAllowanceRelatedToDeferredStateIncomeTaxes_DB06A90A93F3CED9FBF80D704D6B5930" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Change in valuation allowance related to deferred state income taxes.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_ChangeInValuationAllowanceRelatedToDeferredStateIncomeTaxes" xlink:label="loc_arnc_ChangeInValuationAllowanceRelatedToDeferredStateIncomeTaxes_DB06A90A93F3CED9FBF80D704D6B5930" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_ChangeInValuationAllowanceRelatedToDeferredStateIncomeTaxes_DB06A90A93F3CED9FBF80D704D6B5930" xlink:to="lab_arnc_ChangeInValuationAllowanceRelatedToDeferredStateIncomeTaxes_DB06A90A93F3CED9FBF80D704D6B5930" xlink:type="arc" />
    <link:label id="lab_arnc_DeferredTaxAssetsValuationForeignCurrencyTranslation_B16C77A01BCF48895A260D704D6B1094_negatedTerseLabel_en-US" xlink:label="lab_arnc_DeferredTaxAssetsValuationForeignCurrencyTranslation_B16C77A01BCF48895A260D704D6B1094" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:type="resource" xml:lang="en-US">Foreign currency translation</link:label>
    <link:label id="lab_arnc_DeferredTaxAssetsValuationForeignCurrencyTranslation_B16C77A01BCF48895A260D704D6B1094_label_en-US" xlink:label="lab_arnc_DeferredTaxAssetsValuationForeignCurrencyTranslation_B16C77A01BCF48895A260D704D6B1094" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Deferred Tax Assets Valuation Foreign Currency Translation</link:label>
    <link:label id="lab_arnc_DeferredTaxAssetsValuationForeignCurrencyTranslation_B16C77A01BCF48895A260D704D6B1094_documentation_en-US" xlink:label="lab_arnc_DeferredTaxAssetsValuationForeignCurrencyTranslation_B16C77A01BCF48895A260D704D6B1094" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Deferred tax assets valuation foreign currency translation.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_DeferredTaxAssetsValuationForeignCurrencyTranslation" xlink:label="loc_arnc_DeferredTaxAssetsValuationForeignCurrencyTranslation_B16C77A01BCF48895A260D704D6B1094" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_DeferredTaxAssetsValuationForeignCurrencyTranslation_B16C77A01BCF48895A260D704D6B1094" xlink:to="lab_arnc_DeferredTaxAssetsValuationForeignCurrencyTranslation_B16C77A01BCF48895A260D704D6B1094" xlink:type="arc" />
    <link:label id="lab_us-gaap_DeferredTaxAssetsValuationAllowance_94D2BF146286DA48BEB00D704D6B7DD2_periodEndLabel_en-US" xlink:label="lab_us-gaap_DeferredTaxAssetsValuationAllowance_94D2BF146286DA48BEB00D704D6B7DD2" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel" xlink:type="resource" xml:lang="en-US">Balance at end of year</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DeferredTaxAssetsValuationAllowance" xlink:label="loc_us-gaap_DeferredTaxAssetsValuationAllowance_94D2BF146286DA48BEB00D704D6B7DD2" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DeferredTaxAssetsValuationAllowance_94D2BF146286DA48BEB00D704D6B7DD2" xlink:to="lab_us-gaap_DeferredTaxAssetsValuationAllowance_94D2BF146286DA48BEB00D704D6B7DD2" xlink:type="arc" />
    <link:label id="lab_us-gaap_OtherIncomeAndOtherExpenseDisclosureTextBlock_3D47A13DF72A5D7DC2AFDEFABA1EE898_terseLabel_en-US" xlink:label="lab_us-gaap_OtherIncomeAndOtherExpenseDisclosureTextBlock_3D47A13DF72A5D7DC2AFDEFABA1EE898" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Other Expense (Income), Net</link:label>
    <link:label id="lab_us-gaap_OtherIncomeAndOtherExpenseDisclosureTextBlock_3D47A13DF72A5D7DC2AFDEFABA1EE898_label_en-US" xlink:label="lab_us-gaap_OtherIncomeAndOtherExpenseDisclosureTextBlock_3D47A13DF72A5D7DC2AFDEFABA1EE898" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Other Income and Other Expense Disclosure [Text Block]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_OtherIncomeAndOtherExpenseDisclosureTextBlock" xlink:label="loc_us-gaap_OtherIncomeAndOtherExpenseDisclosureTextBlock_3D47A13DF72A5D7DC2AFDEFABA1EE898" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OtherIncomeAndOtherExpenseDisclosureTextBlock_3D47A13DF72A5D7DC2AFDEFABA1EE898" xlink:to="lab_us-gaap_OtherIncomeAndOtherExpenseDisclosureTextBlock_3D47A13DF72A5D7DC2AFDEFABA1EE898" xlink:type="arc" />
    <link:label id="lab_us-gaap_GoodwillAndIntangibleAssetsDisclosureAbstract_B16F98B0C84B9D2B3B4DE244A9B68BCE_label_en-US" xlink:label="lab_us-gaap_GoodwillAndIntangibleAssetsDisclosureAbstract_B16F98B0C84B9D2B3B4DE244A9B68BCE" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Goodwill and Intangible Assets Disclosure [Abstract]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_GoodwillAndIntangibleAssetsDisclosureAbstract" xlink:label="loc_us-gaap_GoodwillAndIntangibleAssetsDisclosureAbstract_B16F98B0C84B9D2B3B4DE244A9B68BCE" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_GoodwillAndIntangibleAssetsDisclosureAbstract_B16F98B0C84B9D2B3B4DE244A9B68BCE" xlink:to="lab_us-gaap_GoodwillAndIntangibleAssetsDisclosureAbstract_B16F98B0C84B9D2B3B4DE244A9B68BCE" xlink:type="arc" />
    <link:label id="lab_us-gaap_ScheduleOfGoodwillTextBlock_ECCB00C41372AD177AC2E244A9B69C16_terseLabel_en-US" xlink:label="lab_us-gaap_ScheduleOfGoodwillTextBlock_ECCB00C41372AD177AC2E244A9B69C16" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Changes in Carrying Amount of Goodwill</link:label>
    <link:label id="lab_us-gaap_ScheduleOfGoodwillTextBlock_ECCB00C41372AD177AC2E244A9B69C16_label_en-US" xlink:label="lab_us-gaap_ScheduleOfGoodwillTextBlock_ECCB00C41372AD177AC2E244A9B69C16" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Schedule of Goodwill [Table Text Block]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ScheduleOfGoodwillTextBlock" xlink:label="loc_us-gaap_ScheduleOfGoodwillTextBlock_ECCB00C41372AD177AC2E244A9B69C16" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfGoodwillTextBlock_ECCB00C41372AD177AC2E244A9B69C16" xlink:to="lab_us-gaap_ScheduleOfGoodwillTextBlock_ECCB00C41372AD177AC2E244A9B69C16" xlink:type="arc" />
    <link:label id="lab_arnc_OtherIntangibleAssetsTextBlock_E5A604CF7D1C3CB8F31EE244A9B65891_terseLabel_en-US" xlink:label="lab_arnc_OtherIntangibleAssetsTextBlock_E5A604CF7D1C3CB8F31EE244A9B65891" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Other Intangible Assets</link:label>
    <link:label id="lab_arnc_OtherIntangibleAssetsTextBlock_E5A604CF7D1C3CB8F31EE244A9B65891_label_en-US" xlink:label="lab_arnc_OtherIntangibleAssetsTextBlock_E5A604CF7D1C3CB8F31EE244A9B65891" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Other Intangible Assets [Text Block]</link:label>
    <link:label id="lab_arnc_OtherIntangibleAssetsTextBlock_E5A604CF7D1C3CB8F31EE244A9B65891_documentation_en-US" xlink:label="lab_arnc_OtherIntangibleAssetsTextBlock_E5A604CF7D1C3CB8F31EE244A9B65891" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Other Intangible Assets [Text Block]</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_OtherIntangibleAssetsTextBlock" xlink:label="loc_arnc_OtherIntangibleAssetsTextBlock_E5A604CF7D1C3CB8F31EE244A9B65891" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_OtherIntangibleAssetsTextBlock_E5A604CF7D1C3CB8F31EE244A9B65891" xlink:to="lab_arnc_OtherIntangibleAssetsTextBlock_E5A604CF7D1C3CB8F31EE244A9B65891" xlink:type="arc" />
    <link:label id="lab_us-gaap_AllowanceForCreditLossesOnFinancingReceivablesTableTextBlock_5BF67BA15282B688AE387C362D8261A4_terseLabel_en-US" xlink:label="lab_us-gaap_AllowanceForCreditLossesOnFinancingReceivablesTableTextBlock_5BF67BA15282B688AE387C362D8261A4" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Schedule of Allowance for Doubtful Accounts</link:label>
    <link:label id="lab_us-gaap_AllowanceForCreditLossesOnFinancingReceivablesTableTextBlock_5BF67BA15282B688AE387C362D8261A4_label_en-US" xlink:label="lab_us-gaap_AllowanceForCreditLossesOnFinancingReceivablesTableTextBlock_5BF67BA15282B688AE387C362D8261A4" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Allowance for Credit Losses on Financing Receivables [Table Text Block]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AllowanceForCreditLossesOnFinancingReceivablesTableTextBlock" xlink:label="loc_us-gaap_AllowanceForCreditLossesOnFinancingReceivablesTableTextBlock_5BF67BA15282B688AE387C362D8261A4" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AllowanceForCreditLossesOnFinancingReceivablesTableTextBlock_5BF67BA15282B688AE387C362D8261A4" xlink:to="lab_us-gaap_AllowanceForCreditLossesOnFinancingReceivablesTableTextBlock_5BF67BA15282B688AE387C362D8261A4" xlink:type="arc" />
    <link:label id="lab_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount_2296D26E1118405F7A0696B480E047D5_terseLabel_en-US" xlink:label="lab_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount_2296D26E1118405F7A0696B480E047D5" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Number of anti-dilutive securities (in shares)</link:label>
    <link:label id="lab_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount_2296D26E1118405F7A0696B480E047D5_label_en-US" xlink:label="lab_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount_2296D26E1118405F7A0696B480E047D5" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount" xlink:label="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount_2296D26E1118405F7A0696B480E047D5" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount_2296D26E1118405F7A0696B480E047D5" xlink:to="lab_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount_2296D26E1118405F7A0696B480E047D5" xlink:type="arc" />
    <link:label id="lab_arnc_WeightedAverageExercisePriceOfUnderwaterOptions_AAA74B40545065C34A7196B480E06A95_terseLabel_en-US" xlink:label="lab_arnc_WeightedAverageExercisePriceOfUnderwaterOptions_AAA74B40545065C34A7196B480E06A95" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Weighted average exercise price of options (usd per share)</link:label>
    <link:label id="lab_arnc_WeightedAverageExercisePriceOfUnderwaterOptions_AAA74B40545065C34A7196B480E06A95_label_en-US" xlink:label="lab_arnc_WeightedAverageExercisePriceOfUnderwaterOptions_AAA74B40545065C34A7196B480E06A95" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Weighted Average Exercise Price Of Underwater Options</link:label>
    <link:label id="lab_arnc_WeightedAverageExercisePriceOfUnderwaterOptions_AAA74B40545065C34A7196B480E06A95_documentation_en-US" xlink:label="lab_arnc_WeightedAverageExercisePriceOfUnderwaterOptions_AAA74B40545065C34A7196B480E06A95" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">The weighted average exercise price of stock options whose individual exercise prices were greater than the average market price of an entity's common stock during the period.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_WeightedAverageExercisePriceOfUnderwaterOptions" xlink:label="loc_arnc_WeightedAverageExercisePriceOfUnderwaterOptions_AAA74B40545065C34A7196B480E06A95" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_WeightedAverageExercisePriceOfUnderwaterOptions_AAA74B40545065C34A7196B480E06A95" xlink:to="lab_arnc_WeightedAverageExercisePriceOfUnderwaterOptions_AAA74B40545065C34A7196B480E06A95" xlink:type="arc" />
    <link:label id="lab_us-gaap_EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate_C4BE3D30FB722E2816D20D7048F664CB_terseLabel_en-US" xlink:label="lab_us-gaap_EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate_C4BE3D30FB722E2816D20D7048F664CB" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">U.S. federal statutory rate</link:label>
    <link:label id="lab_us-gaap_EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate_C4BE3D30FB722E2816D20D7048F664CB_label_en-US" xlink:label="lab_us-gaap_EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate_C4BE3D30FB722E2816D20D7048F664CB" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate" xlink:label="loc_us-gaap_EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate_C4BE3D30FB722E2816D20D7048F664CB" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate_C4BE3D30FB722E2816D20D7048F664CB" xlink:to="lab_us-gaap_EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate_C4BE3D30FB722E2816D20D7048F664CB" xlink:type="arc" />
    <link:label id="lab_us-gaap_EffectiveIncomeTaxRateReconciliationForeignIncomeTaxRateDifferential_CDE69362E6FEB9801BCF0D7048F6150D_terseLabel_en-US" xlink:label="lab_us-gaap_EffectiveIncomeTaxRateReconciliationForeignIncomeTaxRateDifferential_CDE69362E6FEB9801BCF0D7048F6150D" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Taxes on foreign operations</link:label>
    <link:label id="lab_us-gaap_EffectiveIncomeTaxRateReconciliationForeignIncomeTaxRateDifferential_CDE69362E6FEB9801BCF0D7048F6150D_label_en-US" xlink:label="lab_us-gaap_EffectiveIncomeTaxRateReconciliationForeignIncomeTaxRateDifferential_CDE69362E6FEB9801BCF0D7048F6150D" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Effective Income Tax Rate Reconciliation, Foreign Income Tax Rate Differential, Percent</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_EffectiveIncomeTaxRateReconciliationForeignIncomeTaxRateDifferential" xlink:label="loc_us-gaap_EffectiveIncomeTaxRateReconciliationForeignIncomeTaxRateDifferential_CDE69362E6FEB9801BCF0D7048F6150D" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_EffectiveIncomeTaxRateReconciliationForeignIncomeTaxRateDifferential_CDE69362E6FEB9801BCF0D7048F6150D" xlink:to="lab_us-gaap_EffectiveIncomeTaxRateReconciliationForeignIncomeTaxRateDifferential_CDE69362E6FEB9801BCF0D7048F6150D" xlink:type="arc" />
    <link:label id="lab_us-gaap_EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes_3FB9401BC05AC72F2C670D7048F6EFEB_terseLabel_en-US" xlink:label="lab_us-gaap_EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes_3FB9401BC05AC72F2C670D7048F6EFEB" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">U.S. State and local taxes</link:label>
    <link:label id="lab_us-gaap_EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes_3FB9401BC05AC72F2C670D7048F6EFEB_label_en-US" xlink:label="lab_us-gaap_EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes_3FB9401BC05AC72F2C670D7048F6EFEB" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Effective Income Tax Rate Reconciliation, State and Local Income Taxes, Percent</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes" xlink:label="loc_us-gaap_EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes_3FB9401BC05AC72F2C670D7048F6EFEB" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes_3FB9401BC05AC72F2C670D7048F6EFEB" xlink:to="lab_us-gaap_EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes_3FB9401BC05AC72F2C670D7048F6EFEB" xlink:type="arc" />
    <link:label id="lab_arnc_EffectiveIncomeTaxRateReconciliationFederalBenefitOfStateTaxesPercent_1EFED331E09C915F221D0D7048F64CA4_terseLabel_en-US" xlink:label="lab_arnc_EffectiveIncomeTaxRateReconciliationFederalBenefitOfStateTaxesPercent_1EFED331E09C915F221D0D7048F64CA4" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Federal benefit of state tax</link:label>
    <link:label id="lab_arnc_EffectiveIncomeTaxRateReconciliationFederalBenefitOfStateTaxesPercent_1EFED331E09C915F221D0D7048F64CA4_label_en-US" xlink:label="lab_arnc_EffectiveIncomeTaxRateReconciliationFederalBenefitOfStateTaxesPercent_1EFED331E09C915F221D0D7048F64CA4" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Effective Income Tax Rate Reconciliation, Federal Benefit Of State Taxes, Percent</link:label>
    <link:label id="lab_arnc_EffectiveIncomeTaxRateReconciliationFederalBenefitOfStateTaxesPercent_1EFED331E09C915F221D0D7048F64CA4_documentation_en-US" xlink:label="lab_arnc_EffectiveIncomeTaxRateReconciliationFederalBenefitOfStateTaxesPercent_1EFED331E09C915F221D0D7048F64CA4" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Effective Income Tax Rate Reconciliation, Federal Benefit of State Taxes, Percent</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_EffectiveIncomeTaxRateReconciliationFederalBenefitOfStateTaxesPercent" xlink:label="loc_arnc_EffectiveIncomeTaxRateReconciliationFederalBenefitOfStateTaxesPercent_1EFED331E09C915F221D0D7048F64CA4" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_EffectiveIncomeTaxRateReconciliationFederalBenefitOfStateTaxesPercent_1EFED331E09C915F221D0D7048F64CA4" xlink:to="lab_arnc_EffectiveIncomeTaxRateReconciliationFederalBenefitOfStateTaxesPercent_1EFED331E09C915F221D0D7048F64CA4" xlink:type="arc" />
    <link:label id="lab_arnc_EffectiveIncomeTaxRateReconciliationDeductibleExpenseRestructuringChargesPercent_F2F0095ABD6112169BD60D7048F709FB_negatedLabel_en-US" xlink:label="lab_arnc_EffectiveIncomeTaxRateReconciliationDeductibleExpenseRestructuringChargesPercent_F2F0095ABD6112169BD60D7048F709FB" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xml:lang="en-US">Permanent differences on restructuring and other charges and asset disposals</link:label>
    <link:label id="lab_arnc_EffectiveIncomeTaxRateReconciliationDeductibleExpenseRestructuringChargesPercent_F2F0095ABD6112169BD60D7048F709FB_label_en-US" xlink:label="lab_arnc_EffectiveIncomeTaxRateReconciliationDeductibleExpenseRestructuringChargesPercent_F2F0095ABD6112169BD60D7048F709FB" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Effective Income Tax Rate Reconciliation, Deductible Expense, Restructuring Charges, Percent</link:label>
    <link:label id="lab_arnc_EffectiveIncomeTaxRateReconciliationDeductibleExpenseRestructuringChargesPercent_F2F0095ABD6112169BD60D7048F709FB_documentation_en-US" xlink:label="lab_arnc_EffectiveIncomeTaxRateReconciliationDeductibleExpenseRestructuringChargesPercent_F2F0095ABD6112169BD60D7048F709FB" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Effective Income Tax Rate Reconciliation, Deductible Expense, Restructuring Charges, Percent</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_EffectiveIncomeTaxRateReconciliationDeductibleExpenseRestructuringChargesPercent" xlink:label="loc_arnc_EffectiveIncomeTaxRateReconciliationDeductibleExpenseRestructuringChargesPercent_F2F0095ABD6112169BD60D7048F709FB" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_EffectiveIncomeTaxRateReconciliationDeductibleExpenseRestructuringChargesPercent_F2F0095ABD6112169BD60D7048F709FB" xlink:to="lab_arnc_EffectiveIncomeTaxRateReconciliationDeductibleExpenseRestructuringChargesPercent_F2F0095ABD6112169BD60D7048F709FB" xlink:type="arc" />
    <link:label id="lab_arnc_EffectiveIncomeTaxRateReconciliationNonDeductibleExpenseAcquisitionCost_28A043DB35B76DFB9A560D7048F7E003_terseLabel_en-US" xlink:label="lab_arnc_EffectiveIncomeTaxRateReconciliationNonDeductibleExpenseAcquisitionCost_28A043DB35B76DFB9A560D7048F7E003" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Non-deductible acquisition costs</link:label>
    <link:label id="lab_arnc_EffectiveIncomeTaxRateReconciliationNonDeductibleExpenseAcquisitionCost_28A043DB35B76DFB9A560D7048F7E003_label_en-US" xlink:label="lab_arnc_EffectiveIncomeTaxRateReconciliationNonDeductibleExpenseAcquisitionCost_28A043DB35B76DFB9A560D7048F7E003" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Effective Income Tax Rate Reconciliation Non Deductible Expense Acquisition Cost</link:label>
    <link:label id="lab_arnc_EffectiveIncomeTaxRateReconciliationNonDeductibleExpenseAcquisitionCost_28A043DB35B76DFB9A560D7048F7E003_documentation_en-US" xlink:label="lab_arnc_EffectiveIncomeTaxRateReconciliationNonDeductibleExpenseAcquisitionCost_28A043DB35B76DFB9A560D7048F7E003" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Effective income tax rate reconciliation non deductible expense acquisition cost.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_EffectiveIncomeTaxRateReconciliationNonDeductibleExpenseAcquisitionCost" xlink:label="loc_arnc_EffectiveIncomeTaxRateReconciliationNonDeductibleExpenseAcquisitionCost_28A043DB35B76DFB9A560D7048F7E003" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_EffectiveIncomeTaxRateReconciliationNonDeductibleExpenseAcquisitionCost_28A043DB35B76DFB9A560D7048F7E003" xlink:to="lab_arnc_EffectiveIncomeTaxRateReconciliationNonDeductibleExpenseAcquisitionCost_28A043DB35B76DFB9A560D7048F7E003" xlink:type="arc" />
    <link:label id="lab_us-gaap_EffectiveIncomeTaxRateReconciliationChangeInEnactedTaxRate_00B8B8D1611D3DBF135E0D7048F772A8_verboseLabel_en-US" xlink:label="lab_us-gaap_EffectiveIncomeTaxRateReconciliationChangeInEnactedTaxRate_00B8B8D1611D3DBF135E0D7048F772A8" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Statutory tax rate and law changes</link:label>
    <link:label id="lab_us-gaap_EffectiveIncomeTaxRateReconciliationChangeInEnactedTaxRate_00B8B8D1611D3DBF135E0D7048F772A8_label_en-US" xlink:label="lab_us-gaap_EffectiveIncomeTaxRateReconciliationChangeInEnactedTaxRate_00B8B8D1611D3DBF135E0D7048F772A8" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Effective Income Tax Rate Reconciliation, Change in Enacted Tax Rate, Percent</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_EffectiveIncomeTaxRateReconciliationChangeInEnactedTaxRate" xlink:label="loc_us-gaap_EffectiveIncomeTaxRateReconciliationChangeInEnactedTaxRate_00B8B8D1611D3DBF135E0D7048F772A8" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_EffectiveIncomeTaxRateReconciliationChangeInEnactedTaxRate_00B8B8D1611D3DBF135E0D7048F772A8" xlink:to="lab_us-gaap_EffectiveIncomeTaxRateReconciliationChangeInEnactedTaxRate_00B8B8D1611D3DBF135E0D7048F772A8" xlink:type="arc" />
    <link:label id="lab_us-gaap_EffectiveIncomeTaxRateReconciliationTaxHolidays_401712AFEADEBD01FE090D7048F797DE_negatedLabel_en-US" xlink:label="lab_us-gaap_EffectiveIncomeTaxRateReconciliationTaxHolidays_401712AFEADEBD01FE090D7048F797DE" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xml:lang="en-US">Tax holidays</link:label>
    <link:label id="lab_us-gaap_EffectiveIncomeTaxRateReconciliationTaxHolidays_401712AFEADEBD01FE090D7048F797DE_label_en-US" xlink:label="lab_us-gaap_EffectiveIncomeTaxRateReconciliationTaxHolidays_401712AFEADEBD01FE090D7048F797DE" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Effective Income Tax Rate Reconciliation, Tax Holiday, Percent</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_EffectiveIncomeTaxRateReconciliationTaxHolidays" xlink:label="loc_us-gaap_EffectiveIncomeTaxRateReconciliationTaxHolidays_401712AFEADEBD01FE090D7048F797DE" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_EffectiveIncomeTaxRateReconciliationTaxHolidays_401712AFEADEBD01FE090D7048F797DE" xlink:to="lab_us-gaap_EffectiveIncomeTaxRateReconciliationTaxHolidays_401712AFEADEBD01FE090D7048F797DE" xlink:type="arc" />
    <link:label id="lab_us-gaap_EffectiveIncomeTaxRateReconciliationChangeInDeferredTaxAssetsValuationAllowance_D3000C53B0194DC5B0CD0D7048F79999_terseLabel_en-US" xlink:label="lab_us-gaap_EffectiveIncomeTaxRateReconciliationChangeInDeferredTaxAssetsValuationAllowance_D3000C53B0194DC5B0CD0D7048F79999" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Changes in valuation allowances</link:label>
    <link:label id="lab_us-gaap_EffectiveIncomeTaxRateReconciliationChangeInDeferredTaxAssetsValuationAllowance_D3000C53B0194DC5B0CD0D7048F79999_label_en-US" xlink:label="lab_us-gaap_EffectiveIncomeTaxRateReconciliationChangeInDeferredTaxAssetsValuationAllowance_D3000C53B0194DC5B0CD0D7048F79999" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Effective Income Tax Rate Reconciliation, Change in Deferred Tax Assets Valuation Allowance, Percent</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_EffectiveIncomeTaxRateReconciliationChangeInDeferredTaxAssetsValuationAllowance" xlink:label="loc_us-gaap_EffectiveIncomeTaxRateReconciliationChangeInDeferredTaxAssetsValuationAllowance_D3000C53B0194DC5B0CD0D7048F79999" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_EffectiveIncomeTaxRateReconciliationChangeInDeferredTaxAssetsValuationAllowance_D3000C53B0194DC5B0CD0D7048F79999" xlink:to="lab_us-gaap_EffectiveIncomeTaxRateReconciliationChangeInDeferredTaxAssetsValuationAllowance_D3000C53B0194DC5B0CD0D7048F79999" xlink:type="arc" />
    <link:label id="lab_us-gaap_EffectiveIncomeTaxRateReconciliationNondeductibleExpenseImpairmentLosses_03150A11646D4AF00EE60D7048F76BCE_terseLabel_en-US" xlink:label="lab_us-gaap_EffectiveIncomeTaxRateReconciliationNondeductibleExpenseImpairmentLosses_03150A11646D4AF00EE60D7048F76BCE" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Impairment of goodwill</link:label>
    <link:label id="lab_us-gaap_EffectiveIncomeTaxRateReconciliationNondeductibleExpenseImpairmentLosses_03150A11646D4AF00EE60D7048F76BCE_label_en-US" xlink:label="lab_us-gaap_EffectiveIncomeTaxRateReconciliationNondeductibleExpenseImpairmentLosses_03150A11646D4AF00EE60D7048F76BCE" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Effective Income Tax Rate Reconciliation, Nondeductible Expense, Impairment Losses, Percent</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_EffectiveIncomeTaxRateReconciliationNondeductibleExpenseImpairmentLosses" xlink:label="loc_us-gaap_EffectiveIncomeTaxRateReconciliationNondeductibleExpenseImpairmentLosses_03150A11646D4AF00EE60D7048F76BCE" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_EffectiveIncomeTaxRateReconciliationNondeductibleExpenseImpairmentLosses_03150A11646D4AF00EE60D7048F76BCE" xlink:to="lab_us-gaap_EffectiveIncomeTaxRateReconciliationNondeductibleExpenseImpairmentLosses_03150A11646D4AF00EE60D7048F76BCE" xlink:type="arc" />
    <link:label id="lab_us-gaap_EffectiveIncomeTaxRateReconciliationNondeductibleExpenseLifeInsurance_2E0CDFF3F4F7AED9C05B0D7048F85C30_negatedLabel_en-US" xlink:label="lab_us-gaap_EffectiveIncomeTaxRateReconciliationNondeductibleExpenseLifeInsurance_2E0CDFF3F4F7AED9C05B0D7048F85C30" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xml:lang="en-US">Company-owned life insurance/split-dollar net premiums</link:label>
    <link:label id="lab_us-gaap_EffectiveIncomeTaxRateReconciliationNondeductibleExpenseLifeInsurance_2E0CDFF3F4F7AED9C05B0D7048F85C30_label_en-US" xlink:label="lab_us-gaap_EffectiveIncomeTaxRateReconciliationNondeductibleExpenseLifeInsurance_2E0CDFF3F4F7AED9C05B0D7048F85C30" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Effective Income Tax Rate Reconciliation, Nondeductible Expense, Life Insurance, Percent</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_EffectiveIncomeTaxRateReconciliationNondeductibleExpenseLifeInsurance" xlink:label="loc_us-gaap_EffectiveIncomeTaxRateReconciliationNondeductibleExpenseLifeInsurance_2E0CDFF3F4F7AED9C05B0D7048F85C30" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_EffectiveIncomeTaxRateReconciliationNondeductibleExpenseLifeInsurance_2E0CDFF3F4F7AED9C05B0D7048F85C30" xlink:to="lab_us-gaap_EffectiveIncomeTaxRateReconciliationNondeductibleExpenseLifeInsurance_2E0CDFF3F4F7AED9C05B0D7048F85C30" xlink:type="arc" />
    <link:label id="lab_us-gaap_EffectiveIncomeTaxRateReconciliationTaxContingencies_97F446CB6250346A19770D7048F81CC7_terseLabel_en-US" xlink:label="lab_us-gaap_EffectiveIncomeTaxRateReconciliationTaxContingencies_97F446CB6250346A19770D7048F81CC7" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Changes in uncertain tax positions</link:label>
    <link:label id="lab_us-gaap_EffectiveIncomeTaxRateReconciliationTaxContingencies_97F446CB6250346A19770D7048F81CC7_label_en-US" xlink:label="lab_us-gaap_EffectiveIncomeTaxRateReconciliationTaxContingencies_97F446CB6250346A19770D7048F81CC7" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Effective Income Tax Rate Reconciliation, Tax Contingency, Percent</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_EffectiveIncomeTaxRateReconciliationTaxContingencies" xlink:label="loc_us-gaap_EffectiveIncomeTaxRateReconciliationTaxContingencies_97F446CB6250346A19770D7048F81CC7" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_EffectiveIncomeTaxRateReconciliationTaxContingencies_97F446CB6250346A19770D7048F81CC7" xlink:to="lab_us-gaap_EffectiveIncomeTaxRateReconciliationTaxContingencies_97F446CB6250346A19770D7048F81CC7" xlink:type="arc" />
    <link:label id="lab_us-gaap_EffectiveIncomeTaxRateReconciliationPriorYearIncomeTaxes_1333CDD295A88ED9EC910D7048F83A4C_terseLabel_en-US" xlink:label="lab_us-gaap_EffectiveIncomeTaxRateReconciliationPriorYearIncomeTaxes_1333CDD295A88ED9EC910D7048F83A4C" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Prior year tax adjustments</link:label>
    <link:label id="lab_us-gaap_EffectiveIncomeTaxRateReconciliationPriorYearIncomeTaxes_1333CDD295A88ED9EC910D7048F83A4C_label_en-US" xlink:label="lab_us-gaap_EffectiveIncomeTaxRateReconciliationPriorYearIncomeTaxes_1333CDD295A88ED9EC910D7048F83A4C" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Effective Income Tax Rate Reconciliation, Prior Year Income Taxes, Percent</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_EffectiveIncomeTaxRateReconciliationPriorYearIncomeTaxes" xlink:label="loc_us-gaap_EffectiveIncomeTaxRateReconciliationPriorYearIncomeTaxes_1333CDD295A88ED9EC910D7048F83A4C" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_EffectiveIncomeTaxRateReconciliationPriorYearIncomeTaxes_1333CDD295A88ED9EC910D7048F83A4C" xlink:to="lab_us-gaap_EffectiveIncomeTaxRateReconciliationPriorYearIncomeTaxes_1333CDD295A88ED9EC910D7048F83A4C" xlink:type="arc" />
    <link:label id="lab_us-gaap_EffectiveIncomeTaxRateReconciliationOtherAdjustments_24A36814DDF29DFA4D870D7048F878C4_terseLabel_en-US" xlink:label="lab_us-gaap_EffectiveIncomeTaxRateReconciliationOtherAdjustments_24A36814DDF29DFA4D870D7048F878C4" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Other</link:label>
    <link:label id="lab_us-gaap_EffectiveIncomeTaxRateReconciliationOtherAdjustments_24A36814DDF29DFA4D870D7048F878C4_label_en-US" xlink:label="lab_us-gaap_EffectiveIncomeTaxRateReconciliationOtherAdjustments_24A36814DDF29DFA4D870D7048F878C4" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Effective Income Tax Rate Reconciliation, Other Adjustments, Percent</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_EffectiveIncomeTaxRateReconciliationOtherAdjustments" xlink:label="loc_us-gaap_EffectiveIncomeTaxRateReconciliationOtherAdjustments_24A36814DDF29DFA4D870D7048F878C4" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_EffectiveIncomeTaxRateReconciliationOtherAdjustments_24A36814DDF29DFA4D870D7048F878C4" xlink:to="lab_us-gaap_EffectiveIncomeTaxRateReconciliationOtherAdjustments_24A36814DDF29DFA4D870D7048F878C4" xlink:type="arc" />
    <link:label id="lab_us-gaap_EffectiveIncomeTaxRateContinuingOperations_D8E90D7FA7D4D00268920D7048F86215_totalLabel_en-US" xlink:label="lab_us-gaap_EffectiveIncomeTaxRateContinuingOperations_D8E90D7FA7D4D00268920D7048F86215" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Effective tax rate</link:label>
    <link:label id="lab_us-gaap_EffectiveIncomeTaxRateContinuingOperations_D8E90D7FA7D4D00268920D7048F86215_label_en-US" xlink:label="lab_us-gaap_EffectiveIncomeTaxRateContinuingOperations_D8E90D7FA7D4D00268920D7048F86215" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Effective Income Tax Rate Reconciliation, Percent</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_EffectiveIncomeTaxRateContinuingOperations" xlink:label="loc_us-gaap_EffectiveIncomeTaxRateContinuingOperations_D8E90D7FA7D4D00268920D7048F86215" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_EffectiveIncomeTaxRateContinuingOperations_D8E90D7FA7D4D00268920D7048F86215" xlink:to="lab_us-gaap_EffectiveIncomeTaxRateContinuingOperations_D8E90D7FA7D4D00268920D7048F86215" xlink:type="arc" />
    <link:label id="lab_us-gaap_ScheduleOfCashFlowSupplementalDisclosuresTableTextBlock_F561A3792C6C15F17B0DE248CA705D1E_terseLabel_en-US" xlink:label="lab_us-gaap_ScheduleOfCashFlowSupplementalDisclosuresTableTextBlock_F561A3792C6C15F17B0DE248CA705D1E" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Schedule of Cash Paid for Interest and Income Taxes</link:label>
    <link:label id="lab_us-gaap_ScheduleOfCashFlowSupplementalDisclosuresTableTextBlock_F561A3792C6C15F17B0DE248CA705D1E_label_en-US" xlink:label="lab_us-gaap_ScheduleOfCashFlowSupplementalDisclosuresTableTextBlock_F561A3792C6C15F17B0DE248CA705D1E" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Schedule of Cash Flow, Supplemental Disclosures [Table Text Block]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ScheduleOfCashFlowSupplementalDisclosuresTableTextBlock" xlink:label="loc_us-gaap_ScheduleOfCashFlowSupplementalDisclosuresTableTextBlock_F561A3792C6C15F17B0DE248CA705D1E" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfCashFlowSupplementalDisclosuresTableTextBlock_F561A3792C6C15F17B0DE248CA705D1E" xlink:to="lab_us-gaap_ScheduleOfCashFlowSupplementalDisclosuresTableTextBlock_F561A3792C6C15F17B0DE248CA705D1E" xlink:type="arc" />
    <link:label id="lab_us-gaap_DefinedBenefitPlanExpectedAmortizationOfGainLossNextFiscalYear_A2CAAC407EDFE71BDC80CE6F49CBCD2A_negatedTerseLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanExpectedAmortizationOfGainLossNextFiscalYear_A2CAAC407EDFE71BDC80CE6F49CBCD2A" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:type="resource" xml:lang="en-US">Net actuarial loss recognition</link:label>
    <link:label id="lab_us-gaap_DefinedBenefitPlanExpectedAmortizationOfGainLossNextFiscalYear_A2CAAC407EDFE71BDC80CE6F49CBCD2A_label_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanExpectedAmortizationOfGainLossNextFiscalYear_A2CAAC407EDFE71BDC80CE6F49CBCD2A" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Expected Amortization of Gain (Loss), Next Fiscal Year</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DefinedBenefitPlanExpectedAmortizationOfGainLossNextFiscalYear" xlink:label="loc_us-gaap_DefinedBenefitPlanExpectedAmortizationOfGainLossNextFiscalYear_A2CAAC407EDFE71BDC80CE6F49CBCD2A" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanExpectedAmortizationOfGainLossNextFiscalYear_A2CAAC407EDFE71BDC80CE6F49CBCD2A" xlink:to="lab_us-gaap_DefinedBenefitPlanExpectedAmortizationOfGainLossNextFiscalYear_A2CAAC407EDFE71BDC80CE6F49CBCD2A" xlink:type="arc" />
    <link:label id="lab_us-gaap_DefinedBenefitPlanExpectedAmortizationOfPriorServiceCostCreditNextFiscalYear_C0CAEFEBAD1BBB575289CE6F49CB8313_terseLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanExpectedAmortizationOfPriorServiceCostCreditNextFiscalYear_C0CAEFEBAD1BBB575289CE6F49CB8313" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Prior service cost (benefit) recognition</link:label>
    <link:label id="lab_us-gaap_DefinedBenefitPlanExpectedAmortizationOfPriorServiceCostCreditNextFiscalYear_C0CAEFEBAD1BBB575289CE6F49CB8313_label_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanExpectedAmortizationOfPriorServiceCostCreditNextFiscalYear_C0CAEFEBAD1BBB575289CE6F49CB8313" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Expected Amortization of Prior Service Cost (Credit), Next Fiscal Year</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DefinedBenefitPlanExpectedAmortizationOfPriorServiceCostCreditNextFiscalYear" xlink:label="loc_us-gaap_DefinedBenefitPlanExpectedAmortizationOfPriorServiceCostCreditNextFiscalYear_C0CAEFEBAD1BBB575289CE6F49CB8313" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanExpectedAmortizationOfPriorServiceCostCreditNextFiscalYear_C0CAEFEBAD1BBB575289CE6F49CB8313" xlink:to="lab_us-gaap_DefinedBenefitPlanExpectedAmortizationOfPriorServiceCostCreditNextFiscalYear_C0CAEFEBAD1BBB575289CE6F49CB8313" xlink:type="arc" />
    <link:label id="lab_us-gaap_ScheduleOfDefinedBenefitPlansDisclosuresTextBlock_4003735E061567FC0B0BBA4BBE3F66A2_terseLabel_en-US" xlink:label="lab_us-gaap_ScheduleOfDefinedBenefitPlansDisclosuresTextBlock_4003735E061567FC0B0BBA4BBE3F66A2" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Schedule of Obligations and Funded Status</link:label>
    <link:label id="lab_us-gaap_ScheduleOfDefinedBenefitPlansDisclosuresTextBlock_4003735E061567FC0B0BBA4BBE3F66A2_label_en-US" xlink:label="lab_us-gaap_ScheduleOfDefinedBenefitPlansDisclosuresTextBlock_4003735E061567FC0B0BBA4BBE3F66A2" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Schedule of Defined Benefit Plans Disclosures [Table Text Block]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ScheduleOfDefinedBenefitPlansDisclosuresTextBlock" xlink:label="loc_us-gaap_ScheduleOfDefinedBenefitPlansDisclosuresTextBlock_4003735E061567FC0B0BBA4BBE3F66A2" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfDefinedBenefitPlansDisclosuresTextBlock_4003735E061567FC0B0BBA4BBE3F66A2" xlink:to="lab_us-gaap_ScheduleOfDefinedBenefitPlansDisclosuresTextBlock_4003735E061567FC0B0BBA4BBE3F66A2" xlink:type="arc" />
    <link:label id="lab_us-gaap_ScheduleOfBenefitObligationsInExcessOfFairValueOfPlanAssetsTableTextBlock_E3654E82651DD548DE13BA4BBE3FA6B7_terseLabel_en-US" xlink:label="lab_us-gaap_ScheduleOfBenefitObligationsInExcessOfFairValueOfPlanAssetsTableTextBlock_E3654E82651DD548DE13BA4BBE3FA6B7" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Schedule of Pension Plan Benefit Obligations</link:label>
    <link:label id="lab_us-gaap_ScheduleOfBenefitObligationsInExcessOfFairValueOfPlanAssetsTableTextBlock_E3654E82651DD548DE13BA4BBE3FA6B7_label_en-US" xlink:label="lab_us-gaap_ScheduleOfBenefitObligationsInExcessOfFairValueOfPlanAssetsTableTextBlock_E3654E82651DD548DE13BA4BBE3FA6B7" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Schedule of Benefit Obligations in Excess of Fair Value of Plan Assets [Table Text Block]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ScheduleOfBenefitObligationsInExcessOfFairValueOfPlanAssetsTableTextBlock" xlink:label="loc_us-gaap_ScheduleOfBenefitObligationsInExcessOfFairValueOfPlanAssetsTableTextBlock_E3654E82651DD548DE13BA4BBE3FA6B7" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfBenefitObligationsInExcessOfFairValueOfPlanAssetsTableTextBlock_E3654E82651DD548DE13BA4BBE3FA6B7" xlink:to="lab_us-gaap_ScheduleOfBenefitObligationsInExcessOfFairValueOfPlanAssetsTableTextBlock_E3654E82651DD548DE13BA4BBE3FA6B7" xlink:type="arc" />
    <link:label id="lab_arnc_ScheduleOfComponentsOfNetPeriodicBenefitCostTextBlock_0C2FA69B68A7CF45ADFBBA4BBE3F71BD_terseLabel_en-US" xlink:label="lab_arnc_ScheduleOfComponentsOfNetPeriodicBenefitCostTextBlock_0C2FA69B68A7CF45ADFBBA4BBE3F71BD" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Components of Net Periodic Benefit Cost</link:label>
    <link:label id="lab_arnc_ScheduleOfComponentsOfNetPeriodicBenefitCostTextBlock_0C2FA69B68A7CF45ADFBBA4BBE3F71BD_label_en-US" xlink:label="lab_arnc_ScheduleOfComponentsOfNetPeriodicBenefitCostTextBlock_0C2FA69B68A7CF45ADFBBA4BBE3F71BD" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Schedule Of Components Of Net Periodic Benefit Cost [Text Block]</link:label>
    <link:label id="lab_arnc_ScheduleOfComponentsOfNetPeriodicBenefitCostTextBlock_0C2FA69B68A7CF45ADFBBA4BBE3F71BD_documentation_en-US" xlink:label="lab_arnc_ScheduleOfComponentsOfNetPeriodicBenefitCostTextBlock_0C2FA69B68A7CF45ADFBBA4BBE3F71BD" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Schedule of components of net periodic benefit cost table text block.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_ScheduleOfComponentsOfNetPeriodicBenefitCostTextBlock" xlink:label="loc_arnc_ScheduleOfComponentsOfNetPeriodicBenefitCostTextBlock_0C2FA69B68A7CF45ADFBBA4BBE3F71BD" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_ScheduleOfComponentsOfNetPeriodicBenefitCostTextBlock_0C2FA69B68A7CF45ADFBBA4BBE3F71BD" xlink:to="lab_arnc_ScheduleOfComponentsOfNetPeriodicBenefitCostTextBlock_0C2FA69B68A7CF45ADFBBA4BBE3F71BD" xlink:type="arc" />
    <link:label id="lab_us-gaap_ScheduleOfNetPeriodicBenefitCostNotYetRecognizedTableTextBlock_187B9770BC6ED5B48CADBA6FC23F7239_terseLabel_en-US" xlink:label="lab_us-gaap_ScheduleOfNetPeriodicBenefitCostNotYetRecognizedTableTextBlock_187B9770BC6ED5B48CADBA6FC23F7239" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Amounts Expected to be Recognized in Net Periodic Benefit Cost</link:label>
    <link:label id="lab_us-gaap_ScheduleOfNetPeriodicBenefitCostNotYetRecognizedTableTextBlock_187B9770BC6ED5B48CADBA6FC23F7239_label_en-US" xlink:label="lab_us-gaap_ScheduleOfNetPeriodicBenefitCostNotYetRecognizedTableTextBlock_187B9770BC6ED5B48CADBA6FC23F7239" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Schedule of Net Periodic Benefit Cost Not yet Recognized [Table Text Block]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ScheduleOfNetPeriodicBenefitCostNotYetRecognizedTableTextBlock" xlink:label="loc_us-gaap_ScheduleOfNetPeriodicBenefitCostNotYetRecognizedTableTextBlock_187B9770BC6ED5B48CADBA6FC23F7239" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfNetPeriodicBenefitCostNotYetRecognizedTableTextBlock_187B9770BC6ED5B48CADBA6FC23F7239" xlink:to="lab_us-gaap_ScheduleOfNetPeriodicBenefitCostNotYetRecognizedTableTextBlock_187B9770BC6ED5B48CADBA6FC23F7239" xlink:type="arc" />
    <link:label id="lab_us-gaap_ScheduleOfAssumptionsUsedTableTextBlock_C999B3A1E22D73490F79BA4BBE3F6536_terseLabel_en-US" xlink:label="lab_us-gaap_ScheduleOfAssumptionsUsedTableTextBlock_C999B3A1E22D73490F79BA4BBE3F6536" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Schedule of Weighted Average Assumptions Used to Determine Benefit Obligations and Net Periodic Benefit Cost</link:label>
    <link:label id="lab_us-gaap_ScheduleOfAssumptionsUsedTableTextBlock_C999B3A1E22D73490F79BA4BBE3F6536_label_en-US" xlink:label="lab_us-gaap_ScheduleOfAssumptionsUsedTableTextBlock_C999B3A1E22D73490F79BA4BBE3F6536" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Schedule of Assumptions Used [Table Text Block]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ScheduleOfAssumptionsUsedTableTextBlock" xlink:label="loc_us-gaap_ScheduleOfAssumptionsUsedTableTextBlock_C999B3A1E22D73490F79BA4BBE3F6536" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfAssumptionsUsedTableTextBlock_C999B3A1E22D73490F79BA4BBE3F6536" xlink:to="lab_us-gaap_ScheduleOfAssumptionsUsedTableTextBlock_C999B3A1E22D73490F79BA4BBE3F6536" xlink:type="arc" />
    <link:label id="lab_us-gaap_ScheduleOfHealthCareCostTrendRatesTableTextBlock_F2527287F93DFCEC2CFCBA4BBE3FF447_terseLabel_en-US" xlink:label="lab_us-gaap_ScheduleOfHealthCareCostTrendRatesTableTextBlock_F2527287F93DFCEC2CFCBA4BBE3FF447" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Schedule of Assumed Health Care Cost Trend Rates</link:label>
    <link:label id="lab_us-gaap_ScheduleOfHealthCareCostTrendRatesTableTextBlock_F2527287F93DFCEC2CFCBA4BBE3FF447_label_en-US" xlink:label="lab_us-gaap_ScheduleOfHealthCareCostTrendRatesTableTextBlock_F2527287F93DFCEC2CFCBA4BBE3FF447" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Schedule of Health Care Cost Trend Rates [Table Text Block]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ScheduleOfHealthCareCostTrendRatesTableTextBlock" xlink:label="loc_us-gaap_ScheduleOfHealthCareCostTrendRatesTableTextBlock_F2527287F93DFCEC2CFCBA4BBE3FF447" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfHealthCareCostTrendRatesTableTextBlock_F2527287F93DFCEC2CFCBA4BBE3FF447" xlink:to="lab_us-gaap_ScheduleOfHealthCareCostTrendRatesTableTextBlock_F2527287F93DFCEC2CFCBA4BBE3FF447" xlink:type="arc" />
    <link:label id="lab_us-gaap_ScheduleOfChangesInFairValueOfPlanAssetsTableTextBlock_2D3F90B4C9A8F1505106BA4BBE3F095D_terseLabel_en-US" xlink:label="lab_us-gaap_ScheduleOfChangesInFairValueOfPlanAssetsTableTextBlock_2D3F90B4C9A8F1505106BA4BBE3F095D" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Schedule of Fair Value of Pension Plan Assets</link:label>
    <link:label id="lab_us-gaap_ScheduleOfChangesInFairValueOfPlanAssetsTableTextBlock_2D3F90B4C9A8F1505106BA4BBE3F095D_label_en-US" xlink:label="lab_us-gaap_ScheduleOfChangesInFairValueOfPlanAssetsTableTextBlock_2D3F90B4C9A8F1505106BA4BBE3F095D" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Schedule of Changes in Fair Value of Plan Assets [Table Text Block]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ScheduleOfChangesInFairValueOfPlanAssetsTableTextBlock" xlink:label="loc_us-gaap_ScheduleOfChangesInFairValueOfPlanAssetsTableTextBlock_2D3F90B4C9A8F1505106BA4BBE3F095D" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfChangesInFairValueOfPlanAssetsTableTextBlock_2D3F90B4C9A8F1505106BA4BBE3F095D" xlink:to="lab_us-gaap_ScheduleOfChangesInFairValueOfPlanAssetsTableTextBlock_2D3F90B4C9A8F1505106BA4BBE3F095D" xlink:type="arc" />
    <link:label id="lab_us-gaap_ScheduleOfAllocationOfPlanAssetsTableTextBlock_3F748D505F874A2208EBBA4BBE3F1211_terseLabel_en-US" xlink:label="lab_us-gaap_ScheduleOfAllocationOfPlanAssetsTableTextBlock_3F748D505F874A2208EBBA4BBE3F1211" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Schedule of Pension and Postretirement Plans Investment Policy and Weighted Average Asset Allocations</link:label>
    <link:label id="lab_us-gaap_ScheduleOfAllocationOfPlanAssetsTableTextBlock_3F748D505F874A2208EBBA4BBE3F1211_label_en-US" xlink:label="lab_us-gaap_ScheduleOfAllocationOfPlanAssetsTableTextBlock_3F748D505F874A2208EBBA4BBE3F1211" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Schedule of Allocation of Plan Assets [Table Text Block]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ScheduleOfAllocationOfPlanAssetsTableTextBlock" xlink:label="loc_us-gaap_ScheduleOfAllocationOfPlanAssetsTableTextBlock_3F748D505F874A2208EBBA4BBE3F1211" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfAllocationOfPlanAssetsTableTextBlock_3F748D505F874A2208EBBA4BBE3F1211" xlink:to="lab_us-gaap_ScheduleOfAllocationOfPlanAssetsTableTextBlock_3F748D505F874A2208EBBA4BBE3F1211" xlink:type="arc" />
    <link:label id="lab_us-gaap_ScheduleOfExpectedBenefitPaymentsTableTextBlock_ECB1A1833C77D178702ABA4BBE3FDCA4_terseLabel_en-US" xlink:label="lab_us-gaap_ScheduleOfExpectedBenefitPaymentsTableTextBlock_ECB1A1833C77D178702ABA4BBE3FDCA4" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Schedule of Benefit Payments Expected to be Paid and Expected Medicare Part D Subsidy Receipts</link:label>
    <link:label id="lab_us-gaap_ScheduleOfExpectedBenefitPaymentsTableTextBlock_ECB1A1833C77D178702ABA4BBE3FDCA4_label_en-US" xlink:label="lab_us-gaap_ScheduleOfExpectedBenefitPaymentsTableTextBlock_ECB1A1833C77D178702ABA4BBE3FDCA4" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Schedule of Expected Benefit Payments [Table Text Block]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ScheduleOfExpectedBenefitPaymentsTableTextBlock" xlink:label="loc_us-gaap_ScheduleOfExpectedBenefitPaymentsTableTextBlock_ECB1A1833C77D178702ABA4BBE3FDCA4" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfExpectedBenefitPaymentsTableTextBlock_ECB1A1833C77D178702ABA4BBE3FDCA4" xlink:to="lab_us-gaap_ScheduleOfExpectedBenefitPaymentsTableTextBlock_ECB1A1833C77D178702ABA4BBE3FDCA4" xlink:type="arc" />
    <link:label id="lab_us-gaap_DebtDisclosureTextBlock_B0424BB2349A7EB2DD7CE244A99EFFD3_terseLabel_en-US" xlink:label="lab_us-gaap_DebtDisclosureTextBlock_B0424BB2349A7EB2DD7CE244A99EFFD3" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Debt</link:label>
    <link:label id="lab_us-gaap_DebtDisclosureTextBlock_B0424BB2349A7EB2DD7CE244A99EFFD3_label_en-US" xlink:label="lab_us-gaap_DebtDisclosureTextBlock_B0424BB2349A7EB2DD7CE244A99EFFD3" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Debt Disclosure [Text Block]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DebtDisclosureTextBlock" xlink:label="loc_us-gaap_DebtDisclosureTextBlock_B0424BB2349A7EB2DD7CE244A99EFFD3" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DebtDisclosureTextBlock_B0424BB2349A7EB2DD7CE244A99EFFD3" xlink:to="lab_us-gaap_DebtDisclosureTextBlock_B0424BB2349A7EB2DD7CE244A99EFFD3" xlink:type="arc" />
    <link:label id="lab_us-gaap_ScheduleOfProductInformationTable_3080934AC384A5A9539A06E20E3A15CF_terseLabel_en-US" xlink:label="lab_us-gaap_ScheduleOfProductInformationTable_3080934AC384A5A9539A06E20E3A15CF" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Schedule of Product Information [Table]</link:label>
    <link:label id="lab_us-gaap_ScheduleOfProductInformationTable_3080934AC384A5A9539A06E20E3A15CF_label_en-US" xlink:label="lab_us-gaap_ScheduleOfProductInformationTable_3080934AC384A5A9539A06E20E3A15CF" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Schedule of Product Information [Table]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ScheduleOfProductInformationTable" xlink:label="loc_us-gaap_ScheduleOfProductInformationTable_3080934AC384A5A9539A06E20E3A15CF" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfProductInformationTable_3080934AC384A5A9539A06E20E3A15CF" xlink:to="lab_us-gaap_ScheduleOfProductInformationTable_3080934AC384A5A9539A06E20E3A15CF" xlink:type="arc" />
    <link:label id="lab_arnc_FlatRolledAluminumMember_F9331D4D667136D542D206E20E3B0A0B_terseLabel_en-US" xlink:label="lab_arnc_FlatRolledAluminumMember_F9331D4D667136D542D206E20E3B0A0B" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Innovative flat-rolled products</link:label>
    <link:label id="lab_arnc_FlatRolledAluminumMember_F9331D4D667136D542D206E20E3B0A0B_label_en-US" xlink:label="lab_arnc_FlatRolledAluminumMember_F9331D4D667136D542D206E20E3B0A0B" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Flat Rolled Aluminum [Member]</link:label>
    <link:label id="lab_arnc_FlatRolledAluminumMember_F9331D4D667136D542D206E20E3B0A0B_documentation_en-US" xlink:label="lab_arnc_FlatRolledAluminumMember_F9331D4D667136D542D206E20E3B0A0B" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Flat rolled aluminum.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_FlatRolledAluminumMember" xlink:label="loc_arnc_FlatRolledAluminumMember_F9331D4D667136D542D206E20E3B0A0B" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_FlatRolledAluminumMember_F9331D4D667136D542D206E20E3B0A0B" xlink:to="lab_arnc_FlatRolledAluminumMember_F9331D4D667136D542D206E20E3B0A0B" xlink:type="arc" />
    <link:label id="lab_arnc_AlcoaFasteningSystemsAndRingsMember_6A44000D37CC6BF6B16506E20E3B113E_terseLabel_en-US" xlink:label="lab_arnc_AlcoaFasteningSystemsAndRingsMember_6A44000D37CC6BF6B16506E20E3B113E" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Engines</link:label>
    <link:label id="lab_arnc_AlcoaFasteningSystemsAndRingsMember_6A44000D37CC6BF6B16506E20E3B113E_label_en-US" xlink:label="lab_arnc_AlcoaFasteningSystemsAndRingsMember_6A44000D37CC6BF6B16506E20E3B113E" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Alcoa Fastening Systems And Rings [Member]</link:label>
    <link:label id="lab_arnc_AlcoaFasteningSystemsAndRingsMember_6A44000D37CC6BF6B16506E20E3B113E_documentation_en-US" xlink:label="lab_arnc_AlcoaFasteningSystemsAndRingsMember_6A44000D37CC6BF6B16506E20E3B113E" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Alcoa fastening systems.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_AlcoaFasteningSystemsAndRingsMember" xlink:label="loc_arnc_AlcoaFasteningSystemsAndRingsMember_6A44000D37CC6BF6B16506E20E3B113E" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_AlcoaFasteningSystemsAndRingsMember_6A44000D37CC6BF6B16506E20E3B113E" xlink:to="lab_arnc_AlcoaFasteningSystemsAndRingsMember_6A44000D37CC6BF6B16506E20E3B113E" xlink:type="arc" />
    <link:label id="lab_arnc_InvestmentCastingsMember_35FBEBA47225640800E406E20E3C6C28_terseLabel_en-US" xlink:label="lab_arnc_InvestmentCastingsMember_35FBEBA47225640800E406E20E3C6C28" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Engineered structures</link:label>
    <link:label id="lab_arnc_InvestmentCastingsMember_35FBEBA47225640800E406E20E3C6C28_label_en-US" xlink:label="lab_arnc_InvestmentCastingsMember_35FBEBA47225640800E406E20E3C6C28" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Investment Castings [Member]</link:label>
    <link:label id="lab_arnc_InvestmentCastingsMember_35FBEBA47225640800E406E20E3C6C28_documentation_en-US" xlink:label="lab_arnc_InvestmentCastingsMember_35FBEBA47225640800E406E20E3C6C28" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Investment castings.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_InvestmentCastingsMember" xlink:label="loc_arnc_InvestmentCastingsMember_35FBEBA47225640800E406E20E3C6C28" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_InvestmentCastingsMember_35FBEBA47225640800E406E20E3C6C28" xlink:to="lab_arnc_InvestmentCastingsMember_35FBEBA47225640800E406E20E3C6C28" xlink:type="arc" />
    <link:label id="lab_arnc_OtherExtrudedAndForgedProductsMember_9C0EB4CBE246AABC38FE06E20E3C4DAE_terseLabel_en-US" xlink:label="lab_arnc_OtherExtrudedAndForgedProductsMember_9C0EB4CBE246AABC38FE06E20E3C4DAE" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Fastening systems</link:label>
    <link:label id="lab_arnc_OtherExtrudedAndForgedProductsMember_9C0EB4CBE246AABC38FE06E20E3C4DAE_label_en-US" xlink:label="lab_arnc_OtherExtrudedAndForgedProductsMember_9C0EB4CBE246AABC38FE06E20E3C4DAE" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Other Extruded And Forged Products [Member]</link:label>
    <link:label id="lab_arnc_OtherExtrudedAndForgedProductsMember_9C0EB4CBE246AABC38FE06E20E3C4DAE_documentation_en-US" xlink:label="lab_arnc_OtherExtrudedAndForgedProductsMember_9C0EB4CBE246AABC38FE06E20E3C4DAE" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Other Extruded And Forged Products [Member]</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_OtherExtrudedAndForgedProductsMember" xlink:label="loc_arnc_OtherExtrudedAndForgedProductsMember_9C0EB4CBE246AABC38FE06E20E3C4DAE" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_OtherExtrudedAndForgedProductsMember_9C0EB4CBE246AABC38FE06E20E3C4DAE" xlink:to="lab_arnc_OtherExtrudedAndForgedProductsMember_9C0EB4CBE246AABC38FE06E20E3C4DAE" xlink:type="arc" />
    <link:label id="lab_arnc_ArchitecturalAluminumSystemsMember_746ACB8127C4769E496106E20E3C17D2_terseLabel_en-US" xlink:label="lab_arnc_ArchitecturalAluminumSystemsMember_746ACB8127C4769E496106E20E3C17D2" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Architectural aluminum systems</link:label>
    <link:label id="lab_arnc_ArchitecturalAluminumSystemsMember_746ACB8127C4769E496106E20E3C17D2_label_en-US" xlink:label="lab_arnc_ArchitecturalAluminumSystemsMember_746ACB8127C4769E496106E20E3C17D2" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Architectural Aluminum Systems [Member]</link:label>
    <link:label id="lab_arnc_ArchitecturalAluminumSystemsMember_746ACB8127C4769E496106E20E3C17D2_documentation_en-US" xlink:label="lab_arnc_ArchitecturalAluminumSystemsMember_746ACB8127C4769E496106E20E3C17D2" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Architectural aluminum systems.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_ArchitecturalAluminumSystemsMember" xlink:label="loc_arnc_ArchitecturalAluminumSystemsMember_746ACB8127C4769E496106E20E3C17D2" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_ArchitecturalAluminumSystemsMember_746ACB8127C4769E496106E20E3C17D2" xlink:to="lab_arnc_ArchitecturalAluminumSystemsMember_746ACB8127C4769E496106E20E3C17D2" xlink:type="arc" />
    <link:label id="lab_arnc_AluminumWheelsMember_C6FD379CC6D1E526305206E20E3CFBA4_terseLabel_en-US" xlink:label="lab_arnc_AluminumWheelsMember_C6FD379CC6D1E526305206E20E3CFBA4" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Aluminum wheels</link:label>
    <link:label id="lab_arnc_AluminumWheelsMember_C6FD379CC6D1E526305206E20E3CFBA4_label_en-US" xlink:label="lab_arnc_AluminumWheelsMember_C6FD379CC6D1E526305206E20E3CFBA4" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Aluminum Wheels [Member]</link:label>
    <link:label id="lab_arnc_AluminumWheelsMember_C6FD379CC6D1E526305206E20E3CFBA4_documentation_en-US" xlink:label="lab_arnc_AluminumWheelsMember_C6FD379CC6D1E526305206E20E3CFBA4" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Aluminum wheels.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_AluminumWheelsMember" xlink:label="loc_arnc_AluminumWheelsMember_C6FD379CC6D1E526305206E20E3CFBA4" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_AluminumWheelsMember_C6FD379CC6D1E526305206E20E3CFBA4" xlink:to="lab_arnc_AluminumWheelsMember_C6FD379CC6D1E526305206E20E3CFBA4" xlink:type="arc" />
    <link:label id="lab_arnc_OtherGroupMember_8FD175CAF762B8FCE36806E20E3C2795_terseLabel_en-US" xlink:label="lab_arnc_OtherGroupMember_8FD175CAF762B8FCE36806E20E3C2795" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Other</link:label>
    <link:label id="lab_arnc_OtherGroupMember_8FD175CAF762B8FCE36806E20E3C2795_label_en-US" xlink:label="lab_arnc_OtherGroupMember_8FD175CAF762B8FCE36806E20E3C2795" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Other Group [Member]</link:label>
    <link:label id="lab_arnc_OtherGroupMember_8FD175CAF762B8FCE36806E20E3C2795_documentation_en-US" xlink:label="lab_arnc_OtherGroupMember_8FD175CAF762B8FCE36806E20E3C2795" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Other group.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_OtherGroupMember" xlink:label="loc_arnc_OtherGroupMember_8FD175CAF762B8FCE36806E20E3C2795" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_OtherGroupMember_8FD175CAF762B8FCE36806E20E3C2795" xlink:to="lab_arnc_OtherGroupMember_8FD175CAF762B8FCE36806E20E3C2795" xlink:type="arc" />
    <link:label id="lab_us-gaap_ProductInformationLineItems_565318756AE8C90D519306E20E3C74AF_terseLabel_en-US" xlink:label="lab_us-gaap_ProductInformationLineItems_565318756AE8C90D519306E20E3C74AF" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Product Information [Line Items]</link:label>
    <link:label id="lab_us-gaap_ProductInformationLineItems_565318756AE8C90D519306E20E3C74AF_label_en-US" xlink:label="lab_us-gaap_ProductInformationLineItems_565318756AE8C90D519306E20E3C74AF" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Product Information [Line Items]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ProductInformationLineItems" xlink:label="loc_us-gaap_ProductInformationLineItems_565318756AE8C90D519306E20E3C74AF" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ProductInformationLineItems_565318756AE8C90D519306E20E3C74AF" xlink:to="lab_us-gaap_ProductInformationLineItems_565318756AE8C90D519306E20E3C74AF" xlink:type="arc" />
    <link:label id="lab_us-gaap_RevenueFromContractWithCustomerIncludingAssessedTax_12BE4396FCC276D9521C06E20E3C4DA4_verboseLabel_en-US" xlink:label="lab_us-gaap_RevenueFromContractWithCustomerIncludingAssessedTax_12BE4396FCC276D9521C06E20E3C4DA4" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Sales</link:label>
    <link:label id="lab_us-gaap_RevenueFromContractWithCustomerIncludingAssessedTax_12BE4396FCC276D9521C06E20E3C4DA4_label_en-US" xlink:label="lab_us-gaap_RevenueFromContractWithCustomerIncludingAssessedTax_12BE4396FCC276D9521C06E20E3C4DA4" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Revenue from Contract with Customer, Including Assessed Tax</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RevenueFromContractWithCustomerIncludingAssessedTax" xlink:label="loc_us-gaap_RevenueFromContractWithCustomerIncludingAssessedTax_12BE4396FCC276D9521C06E20E3C4DA4" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RevenueFromContractWithCustomerIncludingAssessedTax_12BE4396FCC276D9521C06E20E3C4DA4" xlink:to="lab_us-gaap_RevenueFromContractWithCustomerIncludingAssessedTax_12BE4396FCC276D9521C06E20E3C4DA4" xlink:type="arc" />
    <link:label id="lab_us-gaap_StatementOfIncomeAndComprehensiveIncomeAbstract_F61FCB4EBB8D11AA69F6CE6F4B175DEF_label_en-US" xlink:label="lab_us-gaap_StatementOfIncomeAndComprehensiveIncomeAbstract_F61FCB4EBB8D11AA69F6CE6F4B175DEF" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Statement of Comprehensive Income [Abstract]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_StatementOfIncomeAndComprehensiveIncomeAbstract" xlink:label="loc_us-gaap_StatementOfIncomeAndComprehensiveIncomeAbstract_F61FCB4EBB8D11AA69F6CE6F4B175DEF" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_StatementOfIncomeAndComprehensiveIncomeAbstract_F61FCB4EBB8D11AA69F6CE6F4B175DEF" xlink:to="lab_us-gaap_StatementOfIncomeAndComprehensiveIncomeAbstract_F61FCB4EBB8D11AA69F6CE6F4B175DEF" xlink:type="arc" />
    <link:label id="lab_us-gaap_StatementTable_A0432AED5A7EC98390EECE6F4B17AE72_terseLabel_en-US" xlink:label="lab_us-gaap_StatementTable_A0432AED5A7EC98390EECE6F4B17AE72" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Statement [Table]</link:label>
    <link:label id="lab_us-gaap_StatementTable_A0432AED5A7EC98390EECE6F4B17AE72_label_en-US" xlink:label="lab_us-gaap_StatementTable_A0432AED5A7EC98390EECE6F4B17AE72" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Statement [Table]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_StatementTable" xlink:label="loc_us-gaap_StatementTable_A0432AED5A7EC98390EECE6F4B17AE72" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_StatementTable_A0432AED5A7EC98390EECE6F4B17AE72" xlink:to="lab_us-gaap_StatementTable_A0432AED5A7EC98390EECE6F4B17AE72" xlink:type="arc" />
    <link:label id="lab_us-gaap_ParentMember_3741D4F5013C2AEE9078CE6F4B17731B_terseLabel_en-US" xlink:label="lab_us-gaap_ParentMember_3741D4F5013C2AEE9078CE6F4B17731B" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Arconic</link:label>
    <link:label id="lab_us-gaap_ParentMember_3741D4F5013C2AEE9078CE6F4B17731B_label_en-US" xlink:label="lab_us-gaap_ParentMember_3741D4F5013C2AEE9078CE6F4B17731B" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Parent [Member]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ParentMember" xlink:label="loc_us-gaap_ParentMember_3741D4F5013C2AEE9078CE6F4B17731B" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ParentMember_3741D4F5013C2AEE9078CE6F4B17731B" xlink:to="lab_us-gaap_ParentMember_3741D4F5013C2AEE9078CE6F4B17731B" xlink:type="arc" />
    <link:label id="lab_us-gaap_NoncontrollingInterestMember_18F8B8FD8FCC877C1750CE6F4B1B2A3C_terseLabel_en-US" xlink:label="lab_us-gaap_NoncontrollingInterestMember_18F8B8FD8FCC877C1750CE6F4B1B2A3C" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Noncontrolling Interests</link:label>
    <link:label id="lab_us-gaap_NoncontrollingInterestMember_18F8B8FD8FCC877C1750CE6F4B1B2A3C_label_en-US" xlink:label="lab_us-gaap_NoncontrollingInterestMember_18F8B8FD8FCC877C1750CE6F4B1B2A3C" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Noncontrolling Interest [Member]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_NoncontrollingInterestMember" xlink:label="loc_us-gaap_NoncontrollingInterestMember_18F8B8FD8FCC877C1750CE6F4B1B2A3C" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_NoncontrollingInterestMember_18F8B8FD8FCC877C1750CE6F4B1B2A3C" xlink:to="lab_us-gaap_NoncontrollingInterestMember_18F8B8FD8FCC877C1750CE6F4B1B2A3C" xlink:type="arc" />
    <link:label id="lab_us-gaap_StatementLineItems_7A062DD9B15D51256B38CE6F4B1BDD36_terseLabel_en-US" xlink:label="lab_us-gaap_StatementLineItems_7A062DD9B15D51256B38CE6F4B1BDD36" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Statement [Line Items]</link:label>
    <link:label id="lab_us-gaap_StatementLineItems_7A062DD9B15D51256B38CE6F4B1BDD36_label_en-US" xlink:label="lab_us-gaap_StatementLineItems_7A062DD9B15D51256B38CE6F4B1BDD36" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Statement [Line Items]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_StatementLineItems" xlink:label="loc_us-gaap_StatementLineItems_7A062DD9B15D51256B38CE6F4B1BDD36" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_StatementLineItems_7A062DD9B15D51256B38CE6F4B1BDD36" xlink:to="lab_us-gaap_StatementLineItems_7A062DD9B15D51256B38CE6F4B1BDD36" xlink:type="arc" />
    <link:label id="lab_us-gaap_ProfitLoss_AD351C8117CEF08AC497CE6F4B1B27A4_terseLabel_en-US" xlink:label="lab_us-gaap_ProfitLoss_AD351C8117CEF08AC497CE6F4B1B27A4" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Net income (loss)</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ProfitLoss" xlink:label="loc_us-gaap_ProfitLoss_AD351C8117CEF08AC497CE6F4B1B27A4" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ProfitLoss_AD351C8117CEF08AC497CE6F4B1B27A4" xlink:to="lab_us-gaap_ProfitLoss_AD351C8117CEF08AC497CE6F4B1B27A4" xlink:type="arc" />
    <link:label id="lab_us-gaap_OtherComprehensiveIncomeLossNetOfTaxPeriodIncreaseDecreaseAbstract_F492875D75ED35ABA110CE6F4B1B47C2_terseLabel_en-US" xlink:label="lab_us-gaap_OtherComprehensiveIncomeLossNetOfTaxPeriodIncreaseDecreaseAbstract_F492875D75ED35ABA110CE6F4B1B47C2" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Other comprehensive income (loss), net of tax (K):</link:label>
    <link:label id="lab_us-gaap_OtherComprehensiveIncomeLossNetOfTaxPeriodIncreaseDecreaseAbstract_F492875D75ED35ABA110CE6F4B1B47C2_label_en-US" xlink:label="lab_us-gaap_OtherComprehensiveIncomeLossNetOfTaxPeriodIncreaseDecreaseAbstract_F492875D75ED35ABA110CE6F4B1B47C2" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Other Comprehensive Income (Loss), Net of Tax [Abstract]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_OtherComprehensiveIncomeLossNetOfTaxPeriodIncreaseDecreaseAbstract" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTaxPeriodIncreaseDecreaseAbstract_F492875D75ED35ABA110CE6F4B1B47C2" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTaxPeriodIncreaseDecreaseAbstract_F492875D75ED35ABA110CE6F4B1B47C2" xlink:to="lab_us-gaap_OtherComprehensiveIncomeLossNetOfTaxPeriodIncreaseDecreaseAbstract_F492875D75ED35ABA110CE6F4B1B47C2" xlink:type="arc" />
    <link:label id="lab_us-gaap_OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax_4D28057C925A73D5341CCE6F4B1BB826_negatedTerseLabel_en-US" xlink:label="lab_us-gaap_OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax_4D28057C925A73D5341CCE6F4B1BB826" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:type="resource" xml:lang="en-US">Change in unrecognized net actuarial loss and prior service cost/benefit related to pension and other postretirement benefits</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax_4D28057C925A73D5341CCE6F4B1BB826" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax_4D28057C925A73D5341CCE6F4B1BB826" xlink:to="lab_us-gaap_OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax_4D28057C925A73D5341CCE6F4B1BB826" xlink:type="arc" />
    <link:label id="lab_us-gaap_OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax_25765F83F64538996E1CCE6F4B1B42A7_terseLabel_en-US" xlink:label="lab_us-gaap_OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax_25765F83F64538996E1CCE6F4B1B42A7" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Foreign currency translation adjustments</link:label>
    <link:label id="lab_us-gaap_OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax_25765F83F64538996E1CCE6F4B1B42A7_label_en-US" xlink:label="lab_us-gaap_OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax_25765F83F64538996E1CCE6F4B1B42A7" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Net of Tax</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax_25765F83F64538996E1CCE6F4B1B42A7" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax_25765F83F64538996E1CCE6F4B1B42A7" xlink:to="lab_us-gaap_OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax_25765F83F64538996E1CCE6F4B1B42A7" xlink:type="arc" />
    <link:label id="lab_us-gaap_OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax_8F74A4DA7E5380F808A9CE6F4B1B2E8F_terseLabel_en-US" xlink:label="lab_us-gaap_OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax_8F74A4DA7E5380F808A9CE6F4B1B2E8F" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Net change in unrealized gains on available-for-sale securities</link:label>
    <link:label id="lab_us-gaap_OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax_8F74A4DA7E5380F808A9CE6F4B1B2E8F_label_en-US" xlink:label="lab_us-gaap_OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax_8F74A4DA7E5380F808A9CE6F4B1B2E8F" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Other Comprehensive Income (Loss), Securities, Available-for-sale, Adjustment, after Tax</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax_8F74A4DA7E5380F808A9CE6F4B1B2E8F" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax_8F74A4DA7E5380F808A9CE6F4B1B2E8F" xlink:to="lab_us-gaap_OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax_8F74A4DA7E5380F808A9CE6F4B1B2E8F" xlink:type="arc" />
    <link:label id="lab_us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTax_EDFACC934FA73E2A4330CE87784F878C_terseLabel_en-US" xlink:label="lab_us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTax_EDFACC934FA73E2A4330CE87784F878C" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), after Reclassification and Tax</link:label>
    <link:label id="lab_us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTax_EDFACC934FA73E2A4330CE87784F878C_label_en-US" xlink:label="lab_us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTax_EDFACC934FA73E2A4330CE87784F878C" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), after Reclassification and Tax</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTax" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTax_EDFACC934FA73E2A4330CE87784F878C" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTax_EDFACC934FA73E2A4330CE87784F878C" xlink:to="lab_us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTax_EDFACC934FA73E2A4330CE87784F878C" xlink:type="arc" />
    <link:label id="lab_us-gaap_ComprehensiveIncomeNetOfTax_E7D7484702FB3E73FB65CE6F4B1B5EE1_totalLabel_en-US" xlink:label="lab_us-gaap_ComprehensiveIncomeNetOfTax_E7D7484702FB3E73FB65CE6F4B1B5EE1" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Comprehensive income (loss)</link:label>
    <link:label id="lab_us-gaap_ComprehensiveIncomeNetOfTax_E7D7484702FB3E73FB65CE6F4B1B5EE1_label_en-US" xlink:label="lab_us-gaap_ComprehensiveIncomeNetOfTax_E7D7484702FB3E73FB65CE6F4B1B5EE1" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Comprehensive Income (Loss), Net of Tax, Attributable to Parent</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ComprehensiveIncomeNetOfTax" xlink:label="loc_us-gaap_ComprehensiveIncomeNetOfTax_E7D7484702FB3E73FB65CE6F4B1B5EE1" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ComprehensiveIncomeNetOfTax_E7D7484702FB3E73FB65CE6F4B1B5EE1" xlink:to="lab_us-gaap_ComprehensiveIncomeNetOfTax_E7D7484702FB3E73FB65CE6F4B1B5EE1" xlink:type="arc" />
    <link:label id="lab_us-gaap_ScheduleOfGoodwillTable_072FC91BBB08C7BA3998E244A9A63942_terseLabel_en-US" xlink:label="lab_us-gaap_ScheduleOfGoodwillTable_072FC91BBB08C7BA3998E244A9A63942" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Schedule of Goodwill [Table]</link:label>
    <link:label id="lab_us-gaap_ScheduleOfGoodwillTable_072FC91BBB08C7BA3998E244A9A63942_label_en-US" xlink:label="lab_us-gaap_ScheduleOfGoodwillTable_072FC91BBB08C7BA3998E244A9A63942" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Schedule of Goodwill [Table]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ScheduleOfGoodwillTable" xlink:label="loc_us-gaap_ScheduleOfGoodwillTable_072FC91BBB08C7BA3998E244A9A63942" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfGoodwillTable_072FC91BBB08C7BA3998E244A9A63942" xlink:to="lab_us-gaap_ScheduleOfGoodwillTable_072FC91BBB08C7BA3998E244A9A63942" xlink:type="arc" />
    <link:label id="lab_us-gaap_GoodwillLineItems_7025AB8BBB74F77BD113E244A9AAE366_terseLabel_en-US" xlink:label="lab_us-gaap_GoodwillLineItems_7025AB8BBB74F77BD113E244A9AAE366" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Goodwill [Line Items]</link:label>
    <link:label id="lab_us-gaap_GoodwillLineItems_7025AB8BBB74F77BD113E244A9AAE366_label_en-US" xlink:label="lab_us-gaap_GoodwillLineItems_7025AB8BBB74F77BD113E244A9AAE366" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Goodwill [Line Items]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_GoodwillLineItems" xlink:label="loc_us-gaap_GoodwillLineItems_7025AB8BBB74F77BD113E244A9AAE366" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_GoodwillLineItems_7025AB8BBB74F77BD113E244A9AAE366" xlink:to="lab_us-gaap_GoodwillLineItems_7025AB8BBB74F77BD113E244A9AAE366" xlink:type="arc" />
    <link:label id="lab_us-gaap_AmortizationOfIntangibleAssets_36C78320AAD2E3F68597E244A9AAEA31_terseLabel_en-US" xlink:label="lab_us-gaap_AmortizationOfIntangibleAssets_36C78320AAD2E3F68597E244A9AAEA31" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Amortization of intangible assets</link:label>
    <link:label id="lab_us-gaap_AmortizationOfIntangibleAssets_36C78320AAD2E3F68597E244A9AAEA31_label_en-US" xlink:label="lab_us-gaap_AmortizationOfIntangibleAssets_36C78320AAD2E3F68597E244A9AAEA31" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Amortization of Intangible Assets</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AmortizationOfIntangibleAssets" xlink:label="loc_us-gaap_AmortizationOfIntangibleAssets_36C78320AAD2E3F68597E244A9AAEA31" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AmortizationOfIntangibleAssets_36C78320AAD2E3F68597E244A9AAEA31" xlink:to="lab_us-gaap_AmortizationOfIntangibleAssets_36C78320AAD2E3F68597E244A9AAEA31" xlink:type="arc" />
    <link:label id="lab_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseNextTwelveMonths_A096F925F92E1B63396DE244A9AA2E11_terseLabel_en-US" xlink:label="lab_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseNextTwelveMonths_A096F925F92E1B63396DE244A9AA2E11" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Expected amortization for the year 2019</link:label>
    <link:label id="lab_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseNextTwelveMonths_A096F925F92E1B63396DE244A9AA2E11_label_en-US" xlink:label="lab_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseNextTwelveMonths_A096F925F92E1B63396DE244A9AA2E11" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Finite-Lived Intangible Assets, Amortization Expense, Next Twelve Months</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseNextTwelveMonths" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseNextTwelveMonths_A096F925F92E1B63396DE244A9AA2E11" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseNextTwelveMonths_A096F925F92E1B63396DE244A9AA2E11" xlink:to="lab_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseNextTwelveMonths_A096F925F92E1B63396DE244A9AA2E11" xlink:type="arc" />
    <link:label id="lab_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo_755E3C6EE1E569B2E764E244A9AA6C46_terseLabel_en-US" xlink:label="lab_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo_755E3C6EE1E569B2E764E244A9AA6C46" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Expected amortization for the year 2020</link:label>
    <link:label id="lab_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo_755E3C6EE1E569B2E764E244A9AA6C46_label_en-US" xlink:label="lab_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo_755E3C6EE1E569B2E764E244A9AA6C46" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Finite-Lived Intangible Assets, Amortization Expense, Year Two</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo_755E3C6EE1E569B2E764E244A9AA6C46" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo_755E3C6EE1E569B2E764E244A9AA6C46" xlink:to="lab_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo_755E3C6EE1E569B2E764E244A9AA6C46" xlink:type="arc" />
    <link:label id="lab_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearThree_313E1E96755D5E0529B2E244A9AAA52F_terseLabel_en-US" xlink:label="lab_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearThree_313E1E96755D5E0529B2E244A9AAA52F" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Expected amortization for the year 2021</link:label>
    <link:label id="lab_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearThree_313E1E96755D5E0529B2E244A9AAA52F_label_en-US" xlink:label="lab_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearThree_313E1E96755D5E0529B2E244A9AAA52F" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Finite-Lived Intangible Assets, Amortization Expense, Year Three</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearThree" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearThree_313E1E96755D5E0529B2E244A9AAA52F" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearThree_313E1E96755D5E0529B2E244A9AAA52F" xlink:to="lab_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearThree_313E1E96755D5E0529B2E244A9AAA52F" xlink:type="arc" />
    <link:label id="lab_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearFour_D3D7CBA58E865C8D49D5E244A9AAEC28_terseLabel_en-US" xlink:label="lab_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearFour_D3D7CBA58E865C8D49D5E244A9AAEC28" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Expected amortization for the year 2022</link:label>
    <link:label id="lab_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearFour_D3D7CBA58E865C8D49D5E244A9AAEC28_label_en-US" xlink:label="lab_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearFour_D3D7CBA58E865C8D49D5E244A9AAEC28" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Finite-Lived Intangible Assets, Amortization Expense, Year Four</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearFour" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearFour_D3D7CBA58E865C8D49D5E244A9AAEC28" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearFour_D3D7CBA58E865C8D49D5E244A9AAEC28" xlink:to="lab_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearFour_D3D7CBA58E865C8D49D5E244A9AAEC28" xlink:type="arc" />
    <link:label id="lab_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearFive_86A48BB6B749C55F6B5EE244A9AAD400_terseLabel_en-US" xlink:label="lab_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearFive_86A48BB6B749C55F6B5EE244A9AAD400" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Expected amortization for the year 2023</link:label>
    <link:label id="lab_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearFive_86A48BB6B749C55F6B5EE244A9AAD400_label_en-US" xlink:label="lab_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearFive_86A48BB6B749C55F6B5EE244A9AAD400" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Finite-Lived Intangible Assets, Amortization Expense, Year Five</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearFive" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearFive_86A48BB6B749C55F6B5EE244A9AAD400" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearFive_86A48BB6B749C55F6B5EE244A9AAD400" xlink:to="lab_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearFive_86A48BB6B749C55F6B5EE244A9AAD400" xlink:type="arc" />
    <link:label id="lab_us-gaap_ScheduleOfInventoryCurrentTableTextBlock_6C9E986FBFB7BA3FCD087C362D72D93F_terseLabel_en-US" xlink:label="lab_us-gaap_ScheduleOfInventoryCurrentTableTextBlock_6C9E986FBFB7BA3FCD087C362D72D93F" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Schedule of Inventory Components</link:label>
    <link:label id="lab_us-gaap_ScheduleOfInventoryCurrentTableTextBlock_6C9E986FBFB7BA3FCD087C362D72D93F_label_en-US" xlink:label="lab_us-gaap_ScheduleOfInventoryCurrentTableTextBlock_6C9E986FBFB7BA3FCD087C362D72D93F" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Schedule of Inventory, Current [Table Text Block]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ScheduleOfInventoryCurrentTableTextBlock" xlink:label="loc_us-gaap_ScheduleOfInventoryCurrentTableTextBlock_6C9E986FBFB7BA3FCD087C362D72D93F" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfInventoryCurrentTableTextBlock_6C9E986FBFB7BA3FCD087C362D72D93F" xlink:to="lab_us-gaap_ScheduleOfInventoryCurrentTableTextBlock_6C9E986FBFB7BA3FCD087C362D72D93F" xlink:type="arc" />
    <link:label id="lab_arnc_SlimAluminiumMember_360697E999C24D6CC10FE244A9263D5B_terseLabel_en-US" xlink:label="lab_arnc_SlimAluminiumMember_360697E999C24D6CC10FE244A9263D5B" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Slim Aluminium</link:label>
    <link:label id="lab_arnc_SlimAluminiumMember_360697E999C24D6CC10FE244A9263D5B_label_en-US" xlink:label="lab_arnc_SlimAluminiumMember_360697E999C24D6CC10FE244A9263D5B" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Slim Aluminium [Member]</link:label>
    <link:label id="lab_arnc_SlimAluminiumMember_360697E999C24D6CC10FE244A9263D5B_documentation_en-US" xlink:label="lab_arnc_SlimAluminiumMember_360697E999C24D6CC10FE244A9263D5B" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Slim Aluminium.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_SlimAluminiumMember" xlink:label="loc_arnc_SlimAluminiumMember_360697E999C24D6CC10FE244A9263D5B" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_SlimAluminiumMember_360697E999C24D6CC10FE244A9263D5B" xlink:to="lab_arnc_SlimAluminiumMember_360697E999C24D6CC10FE244A9263D5B" xlink:type="arc" />
    <link:label id="lab_arnc_CashExpenseRelatedToDivestitureOfBusinesses_37E22449E7027CA6B61AE244A92A73E0_terseLabel_en-US" xlink:label="lab_arnc_CashExpenseRelatedToDivestitureOfBusinesses_37E22449E7027CA6B61AE244A92A73E0" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Cash expense related to divestiture of business</link:label>
    <link:label id="lab_arnc_CashExpenseRelatedToDivestitureOfBusinesses_37E22449E7027CA6B61AE244A92A73E0_label_en-US" xlink:label="lab_arnc_CashExpenseRelatedToDivestitureOfBusinesses_37E22449E7027CA6B61AE244A92A73E0" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Cash Expense Related To Divestiture Of Businesses</link:label>
    <link:label id="lab_arnc_CashExpenseRelatedToDivestitureOfBusinesses_37E22449E7027CA6B61AE244A92A73E0_documentation_en-US" xlink:label="lab_arnc_CashExpenseRelatedToDivestitureOfBusinesses_37E22449E7027CA6B61AE244A92A73E0" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Cash expense related to divestiture of businesses.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_CashExpenseRelatedToDivestitureOfBusinesses" xlink:label="loc_arnc_CashExpenseRelatedToDivestitureOfBusinesses_37E22449E7027CA6B61AE244A92A73E0" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_CashExpenseRelatedToDivestitureOfBusinesses_37E22449E7027CA6B61AE244A92A73E0" xlink:to="lab_arnc_CashExpenseRelatedToDivestitureOfBusinesses_37E22449E7027CA6B61AE244A92A73E0" xlink:type="arc" />
    <link:label id="lab_arnc_GuaranteePaymentsToThirdParty_857857CA4EEE832D03CDE244A92AE12C_terseLabel_en-US" xlink:label="lab_arnc_GuaranteePaymentsToThirdParty_857857CA4EEE832D03CDE244A92AE12C" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Guarantee payments to third party</link:label>
    <link:label id="lab_arnc_GuaranteePaymentsToThirdParty_857857CA4EEE832D03CDE244A92AE12C_label_en-US" xlink:label="lab_arnc_GuaranteePaymentsToThirdParty_857857CA4EEE832D03CDE244A92AE12C" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Guarantee Payments To Third Party</link:label>
    <link:label id="lab_arnc_GuaranteePaymentsToThirdParty_857857CA4EEE832D03CDE244A92AE12C_documentation_en-US" xlink:label="lab_arnc_GuaranteePaymentsToThirdParty_857857CA4EEE832D03CDE244A92AE12C" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Guarantee payments to third party.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_GuaranteePaymentsToThirdParty" xlink:label="loc_arnc_GuaranteePaymentsToThirdParty_857857CA4EEE832D03CDE244A92AE12C" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_GuaranteePaymentsToThirdParty_857857CA4EEE832D03CDE244A92AE12C" xlink:to="lab_arnc_GuaranteePaymentsToThirdParty_857857CA4EEE832D03CDE244A92AE12C" xlink:type="arc" />
    <link:label id="lab_us-gaap_GainLossOnSaleOfBusiness_67C27525292C1135FC1CE244A92A5829_negatedTerseLabel_en-US" xlink:label="lab_us-gaap_GainLossOnSaleOfBusiness_67C27525292C1135FC1CE244A92A5829" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:type="resource" xml:lang="en-US">Net loss on divestitures of businesses</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_GainLossOnSaleOfBusiness" xlink:label="loc_us-gaap_GainLossOnSaleOfBusiness_67C27525292C1135FC1CE244A92A5829" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_GainLossOnSaleOfBusiness_67C27525292C1135FC1CE244A92A5829" xlink:to="lab_us-gaap_GainLossOnSaleOfBusiness_67C27525292C1135FC1CE244A92A5829" xlink:type="arc" />
    <link:label id="lab_us-gaap_StatementOfCashFlowsAbstract_486F5AA3E2AF64858FB5E2A5AEC77EB8_label_en-US" xlink:label="lab_us-gaap_StatementOfCashFlowsAbstract_486F5AA3E2AF64858FB5E2A5AEC77EB8" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Statement of Cash Flows [Abstract]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_StatementOfCashFlowsAbstract" xlink:label="loc_us-gaap_StatementOfCashFlowsAbstract_486F5AA3E2AF64858FB5E2A5AEC77EB8" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_StatementOfCashFlowsAbstract_486F5AA3E2AF64858FB5E2A5AEC77EB8" xlink:to="lab_us-gaap_StatementOfCashFlowsAbstract_486F5AA3E2AF64858FB5E2A5AEC77EB8" xlink:type="arc" />
    <link:label id="lab_us-gaap_NetCashProvidedByUsedInOperatingActivitiesContinuingOperationsAbstract_824A7D58B3B98DFBCE99E2A5AEC7E1E5_terseLabel_en-US" xlink:label="lab_us-gaap_NetCashProvidedByUsedInOperatingActivitiesContinuingOperationsAbstract_824A7D58B3B98DFBCE99E2A5AEC7E1E5" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Cash from Operations</link:label>
    <link:label id="lab_us-gaap_NetCashProvidedByUsedInOperatingActivitiesContinuingOperationsAbstract_824A7D58B3B98DFBCE99E2A5AEC7E1E5_label_en-US" xlink:label="lab_us-gaap_NetCashProvidedByUsedInOperatingActivitiesContinuingOperationsAbstract_824A7D58B3B98DFBCE99E2A5AEC7E1E5" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Net Cash Provided by (Used in) Operating Activities, Continuing Operations [Abstract]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_NetCashProvidedByUsedInOperatingActivitiesContinuingOperationsAbstract" xlink:label="loc_us-gaap_NetCashProvidedByUsedInOperatingActivitiesContinuingOperationsAbstract_824A7D58B3B98DFBCE99E2A5AEC7E1E5" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivitiesContinuingOperationsAbstract_824A7D58B3B98DFBCE99E2A5AEC7E1E5" xlink:to="lab_us-gaap_NetCashProvidedByUsedInOperatingActivitiesContinuingOperationsAbstract_824A7D58B3B98DFBCE99E2A5AEC7E1E5" xlink:type="arc" />
    <link:label id="lab_us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract_200D2DA6D7E3F88E335EE2A5AEC7C433_terseLabel_en-US" xlink:label="lab_us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract_200D2DA6D7E3F88E335EE2A5AEC7C433" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Adjustments to reconcile net income (loss) to cash provided from (used for) operations:</link:label>
    <link:label id="lab_us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract_200D2DA6D7E3F88E335EE2A5AEC7C433_label_en-US" xlink:label="lab_us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract_200D2DA6D7E3F88E335EE2A5AEC7C433" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Adjustments to Reconcile Net Income (Loss) to Cash Provided by (Used in) Operating Activities [Abstract]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract" xlink:label="loc_us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract_200D2DA6D7E3F88E335EE2A5AEC7C433" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract_200D2DA6D7E3F88E335EE2A5AEC7C433" xlink:to="lab_us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract_200D2DA6D7E3F88E335EE2A5AEC7C433" xlink:type="arc" />
    <link:label id="lab_us-gaap_DepreciationDepletionAndAmortization_15CCDBF02FE1A0217A3AE2A5AEC7B8FD_terseLabel_en-US" xlink:label="lab_us-gaap_DepreciationDepletionAndAmortization_15CCDBF02FE1A0217A3AE2A5AEC7B8FD" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Depreciation and amortization</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DepreciationDepletionAndAmortization" xlink:label="loc_us-gaap_DepreciationDepletionAndAmortization_15CCDBF02FE1A0217A3AE2A5AEC7B8FD" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DepreciationDepletionAndAmortization_15CCDBF02FE1A0217A3AE2A5AEC7B8FD" xlink:to="lab_us-gaap_DepreciationDepletionAndAmortization_15CCDBF02FE1A0217A3AE2A5AEC7B8FD" xlink:type="arc" />
    <link:label id="lab_us-gaap_DeferredIncomeTaxesAndTaxCredits_98E387BC421DA807874BE2A5AEC782EE_terseLabel_en-US" xlink:label="lab_us-gaap_DeferredIncomeTaxesAndTaxCredits_98E387BC421DA807874BE2A5AEC782EE" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Deferred income taxes</link:label>
    <link:label id="lab_us-gaap_DeferredIncomeTaxesAndTaxCredits_98E387BC421DA807874BE2A5AEC782EE_label_en-US" xlink:label="lab_us-gaap_DeferredIncomeTaxesAndTaxCredits_98E387BC421DA807874BE2A5AEC782EE" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Deferred Income Taxes and Tax Credits</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DeferredIncomeTaxesAndTaxCredits" xlink:label="loc_us-gaap_DeferredIncomeTaxesAndTaxCredits_98E387BC421DA807874BE2A5AEC782EE" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DeferredIncomeTaxesAndTaxCredits_98E387BC421DA807874BE2A5AEC782EE" xlink:to="lab_us-gaap_DeferredIncomeTaxesAndTaxCredits_98E387BC421DA807874BE2A5AEC782EE" xlink:type="arc" />
    <link:label id="lab_us-gaap_IncomeLossFromEquityMethodInvestmentsNetOfDividendsOrDistributions_5149D0AD631E4990E70EE2A5AEC7080A_negatedLabel_en-US" xlink:label="lab_us-gaap_IncomeLossFromEquityMethodInvestmentsNetOfDividendsOrDistributions_5149D0AD631E4990E70EE2A5AEC7080A" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xml:lang="en-US">Equity income, net of dividends</link:label>
    <link:label id="lab_us-gaap_IncomeLossFromEquityMethodInvestmentsNetOfDividendsOrDistributions_5149D0AD631E4990E70EE2A5AEC7080A_label_en-US" xlink:label="lab_us-gaap_IncomeLossFromEquityMethodInvestmentsNetOfDividendsOrDistributions_5149D0AD631E4990E70EE2A5AEC7080A" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Income (Loss) from Equity Method Investments, Net of Dividends or Distributions</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_IncomeLossFromEquityMethodInvestmentsNetOfDividendsOrDistributions" xlink:label="loc_us-gaap_IncomeLossFromEquityMethodInvestmentsNetOfDividendsOrDistributions_5149D0AD631E4990E70EE2A5AEC7080A" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncomeLossFromEquityMethodInvestmentsNetOfDividendsOrDistributions_5149D0AD631E4990E70EE2A5AEC7080A" xlink:to="lab_us-gaap_IncomeLossFromEquityMethodInvestmentsNetOfDividendsOrDistributions_5149D0AD631E4990E70EE2A5AEC7080A" xlink:type="arc" />
    <link:label id="lab_arnc_RestructuringAndOtherCharges_AB6F43D4A155A8D2D843E2A5AEC7866C_terseLabel_en-US" xlink:label="lab_arnc_RestructuringAndOtherCharges_AB6F43D4A155A8D2D843E2A5AEC7866C" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Restructuring and other charges</link:label>
    <link:label id="lab_arnc_RestructuringAndOtherCharges_AB6F43D4A155A8D2D843E2A5AEC7866C_label_en-US" xlink:label="lab_arnc_RestructuringAndOtherCharges_AB6F43D4A155A8D2D843E2A5AEC7866C" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Restructuring And Other Charges</link:label>
    <link:label id="lab_arnc_RestructuringAndOtherCharges_AB6F43D4A155A8D2D843E2A5AEC7866C_documentation_en-US" xlink:label="lab_arnc_RestructuringAndOtherCharges_AB6F43D4A155A8D2D843E2A5AEC7866C" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Restructuring And Other Charges</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_RestructuringAndOtherCharges" xlink:label="loc_arnc_RestructuringAndOtherCharges_AB6F43D4A155A8D2D843E2A5AEC7866C" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_RestructuringAndOtherCharges_AB6F43D4A155A8D2D843E2A5AEC7866C" xlink:to="lab_arnc_RestructuringAndOtherCharges_AB6F43D4A155A8D2D843E2A5AEC7866C" xlink:type="arc" />
    <link:label id="lab_us-gaap_GainLossOnSaleOfInvestments_181762754F9D99D6ED58E2BFD6047A3E_negatedLabel_en-US" xlink:label="lab_us-gaap_GainLossOnSaleOfInvestments_181762754F9D99D6ED58E2BFD6047A3E" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xml:lang="en-US">Net loss (gain) from investing activities - asset sales</link:label>
    <link:label id="lab_us-gaap_GainLossOnSaleOfInvestments_181762754F9D99D6ED58E2BFD6047A3E_label_en-US" xlink:label="lab_us-gaap_GainLossOnSaleOfInvestments_181762754F9D99D6ED58E2BFD6047A3E" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Gain (Loss) on Sale of Investments</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_GainLossOnSaleOfInvestments" xlink:label="loc_us-gaap_GainLossOnSaleOfInvestments_181762754F9D99D6ED58E2BFD6047A3E" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_GainLossOnSaleOfInvestments_181762754F9D99D6ED58E2BFD6047A3E" xlink:to="lab_us-gaap_GainLossOnSaleOfInvestments_181762754F9D99D6ED58E2BFD6047A3E" xlink:type="arc" />
    <link:label id="lab_arnc_DefinedBenefitPensionPlansNetPeriodicBenefitCost_86BF3DAEB155CB82BF5CE2A5AEC763F6_terseLabel_en-US" xlink:label="lab_arnc_DefinedBenefitPensionPlansNetPeriodicBenefitCost_86BF3DAEB155CB82BF5CE2A5AEC763F6" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Net periodic pension benefit cost (G)</link:label>
    <link:label id="lab_arnc_DefinedBenefitPensionPlansNetPeriodicBenefitCost_86BF3DAEB155CB82BF5CE2A5AEC763F6_label_en-US" xlink:label="lab_arnc_DefinedBenefitPensionPlansNetPeriodicBenefitCost_86BF3DAEB155CB82BF5CE2A5AEC763F6" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Benefit Pension Plans Net Periodic Benefit Cost</link:label>
    <link:label id="lab_arnc_DefinedBenefitPensionPlansNetPeriodicBenefitCost_86BF3DAEB155CB82BF5CE2A5AEC763F6_documentation_en-US" xlink:label="lab_arnc_DefinedBenefitPensionPlansNetPeriodicBenefitCost_86BF3DAEB155CB82BF5CE2A5AEC763F6" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">The total amount of net periodic benefit cost for defined benefit pension plans for the period excluding settlements, curtailments, and special termination benefits related to restructuring actions. Periodic benefit costs include the following components: service cost, interest cost, expected return on plan assets, gain (loss), prior service cost or credit, transition asset or obligation, and gain (loss) due to settlements or curtailments.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_DefinedBenefitPensionPlansNetPeriodicBenefitCost" xlink:label="loc_arnc_DefinedBenefitPensionPlansNetPeriodicBenefitCost_86BF3DAEB155CB82BF5CE2A5AEC763F6" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_DefinedBenefitPensionPlansNetPeriodicBenefitCost_86BF3DAEB155CB82BF5CE2A5AEC763F6" xlink:to="lab_arnc_DefinedBenefitPensionPlansNetPeriodicBenefitCost_86BF3DAEB155CB82BF5CE2A5AEC763F6" xlink:type="arc" />
    <link:label id="lab_arnc_IncreaseDecreaseInSharebasedCompensation_DB0A3BE3FACBC801F717E2A5AEC7A5BC_verboseLabel_en-US" xlink:label="lab_arnc_IncreaseDecreaseInSharebasedCompensation_DB0A3BE3FACBC801F717E2A5AEC7A5BC" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Stock-based compensation</link:label>
    <link:label id="lab_arnc_IncreaseDecreaseInSharebasedCompensation_DB0A3BE3FACBC801F717E2A5AEC7A5BC_label_en-US" xlink:label="lab_arnc_IncreaseDecreaseInSharebasedCompensation_DB0A3BE3FACBC801F717E2A5AEC7A5BC" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Increase (Decrease) In Share-based Compensation</link:label>
    <link:label id="lab_arnc_IncreaseDecreaseInSharebasedCompensation_DB0A3BE3FACBC801F717E2A5AEC7A5BC_documentation_en-US" xlink:label="lab_arnc_IncreaseDecreaseInSharebasedCompensation_DB0A3BE3FACBC801F717E2A5AEC7A5BC" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Increase (Decrease) In Share-based Compensation</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_IncreaseDecreaseInSharebasedCompensation" xlink:label="loc_arnc_IncreaseDecreaseInSharebasedCompensation_DB0A3BE3FACBC801F717E2A5AEC7A5BC" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_IncreaseDecreaseInSharebasedCompensation_DB0A3BE3FACBC801F717E2A5AEC7A5BC" xlink:to="lab_arnc_IncreaseDecreaseInSharebasedCompensation_DB0A3BE3FACBC801F717E2A5AEC7A5BC" xlink:type="arc" />
    <link:label id="lab_us-gaap_OtherNoncashIncomeExpense_AEDB6EE75FE03B3E0555E2A5AEC7DB79_negatedLabel_en-US" xlink:label="lab_us-gaap_OtherNoncashIncomeExpense_AEDB6EE75FE03B3E0555E2A5AEC7DB79" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xml:lang="en-US">Other</link:label>
    <link:label id="lab_us-gaap_OtherNoncashIncomeExpense_AEDB6EE75FE03B3E0555E2A5AEC7DB79_label_en-US" xlink:label="lab_us-gaap_OtherNoncashIncomeExpense_AEDB6EE75FE03B3E0555E2A5AEC7DB79" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Other Noncash Income (Expense)</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_OtherNoncashIncomeExpense" xlink:label="loc_us-gaap_OtherNoncashIncomeExpense_AEDB6EE75FE03B3E0555E2A5AEC7DB79" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OtherNoncashIncomeExpense_AEDB6EE75FE03B3E0555E2A5AEC7DB79" xlink:to="lab_us-gaap_OtherNoncashIncomeExpense_AEDB6EE75FE03B3E0555E2A5AEC7DB79" xlink:type="arc" />
    <link:label id="lab_us-gaap_IncreaseDecreaseInOperatingCapitalAbstract_D5271C409BEB4583A0C5E2A5AEC7671D_terseLabel_en-US" xlink:label="lab_us-gaap_IncreaseDecreaseInOperatingCapitalAbstract_D5271C409BEB4583A0C5E2A5AEC7671D" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Changes in assets and liabilities, excluding effects of acquisitions, divestitures, and foreign currency translation adjustments:</link:label>
    <link:label id="lab_us-gaap_IncreaseDecreaseInOperatingCapitalAbstract_D5271C409BEB4583A0C5E2A5AEC7671D_label_en-US" xlink:label="lab_us-gaap_IncreaseDecreaseInOperatingCapitalAbstract_D5271C409BEB4583A0C5E2A5AEC7671D" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Increase (Decrease) in Operating Capital [Abstract]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_IncreaseDecreaseInOperatingCapitalAbstract" xlink:label="loc_us-gaap_IncreaseDecreaseInOperatingCapitalAbstract_D5271C409BEB4583A0C5E2A5AEC7671D" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncreaseDecreaseInOperatingCapitalAbstract_D5271C409BEB4583A0C5E2A5AEC7671D" xlink:to="lab_us-gaap_IncreaseDecreaseInOperatingCapitalAbstract_D5271C409BEB4583A0C5E2A5AEC7671D" xlink:type="arc" />
    <link:label id="lab_us-gaap_IncreaseDecreaseInReceivables_F14AF1544DC4A7BDEDE8E2A5AEC7F416_negatedLabel_en-US" xlink:label="lab_us-gaap_IncreaseDecreaseInReceivables_F14AF1544DC4A7BDEDE8E2A5AEC7F416" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xml:lang="en-US">(Increase) in receivables (A)</link:label>
    <link:label id="lab_us-gaap_IncreaseDecreaseInReceivables_F14AF1544DC4A7BDEDE8E2A5AEC7F416_label_en-US" xlink:label="lab_us-gaap_IncreaseDecreaseInReceivables_F14AF1544DC4A7BDEDE8E2A5AEC7F416" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Increase (Decrease) in Receivables</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_IncreaseDecreaseInReceivables" xlink:label="loc_us-gaap_IncreaseDecreaseInReceivables_F14AF1544DC4A7BDEDE8E2A5AEC7F416" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncreaseDecreaseInReceivables_F14AF1544DC4A7BDEDE8E2A5AEC7F416" xlink:to="lab_us-gaap_IncreaseDecreaseInReceivables_F14AF1544DC4A7BDEDE8E2A5AEC7F416" xlink:type="arc" />
    <link:label id="lab_us-gaap_IncreaseDecreaseInInventories_BADCDC8C5CB9BBCBD335E2A5AEC7A706_negatedLabel_en-US" xlink:label="lab_us-gaap_IncreaseDecreaseInInventories_BADCDC8C5CB9BBCBD335E2A5AEC7A706" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xml:lang="en-US">(Increase) in inventories</link:label>
    <link:label id="lab_us-gaap_IncreaseDecreaseInInventories_BADCDC8C5CB9BBCBD335E2A5AEC7A706_label_en-US" xlink:label="lab_us-gaap_IncreaseDecreaseInInventories_BADCDC8C5CB9BBCBD335E2A5AEC7A706" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Increase (Decrease) in Inventories</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_IncreaseDecreaseInInventories" xlink:label="loc_us-gaap_IncreaseDecreaseInInventories_BADCDC8C5CB9BBCBD335E2A5AEC7A706" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncreaseDecreaseInInventories_BADCDC8C5CB9BBCBD335E2A5AEC7A706" xlink:to="lab_us-gaap_IncreaseDecreaseInInventories_BADCDC8C5CB9BBCBD335E2A5AEC7A706" xlink:type="arc" />
    <link:label id="lab_us-gaap_IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets_B233EF80A23F1217F2B5E2A5AEC7EF39_negatedLabel_en-US" xlink:label="lab_us-gaap_IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets_B233EF80A23F1217F2B5E2A5AEC7EF39" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xml:lang="en-US">(Increase) decrease in prepaid expenses and other current assets</link:label>
    <link:label id="lab_us-gaap_IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets_B233EF80A23F1217F2B5E2A5AEC7EF39_label_en-US" xlink:label="lab_us-gaap_IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets_B233EF80A23F1217F2B5E2A5AEC7EF39" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Increase (Decrease) in Prepaid Expense and Other Assets</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets" xlink:label="loc_us-gaap_IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets_B233EF80A23F1217F2B5E2A5AEC7EF39" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets_B233EF80A23F1217F2B5E2A5AEC7EF39" xlink:to="lab_us-gaap_IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets_B233EF80A23F1217F2B5E2A5AEC7EF39" xlink:type="arc" />
    <link:label id="lab_us-gaap_IncreaseDecreaseInAccountsPayableTrade_9BA59E91678127714FC4E2A5AEC7FFD2_terseLabel_en-US" xlink:label="lab_us-gaap_IncreaseDecreaseInAccountsPayableTrade_9BA59E91678127714FC4E2A5AEC7FFD2" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Increase in accounts payable, trade</link:label>
    <link:label id="lab_us-gaap_IncreaseDecreaseInAccountsPayableTrade_9BA59E91678127714FC4E2A5AEC7FFD2_label_en-US" xlink:label="lab_us-gaap_IncreaseDecreaseInAccountsPayableTrade_9BA59E91678127714FC4E2A5AEC7FFD2" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Increase (Decrease) in Accounts Payable, Trade</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_IncreaseDecreaseInAccountsPayableTrade" xlink:label="loc_us-gaap_IncreaseDecreaseInAccountsPayableTrade_9BA59E91678127714FC4E2A5AEC7FFD2" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncreaseDecreaseInAccountsPayableTrade_9BA59E91678127714FC4E2A5AEC7FFD2" xlink:to="lab_us-gaap_IncreaseDecreaseInAccountsPayableTrade_9BA59E91678127714FC4E2A5AEC7FFD2" xlink:type="arc" />
    <link:label id="lab_us-gaap_IncreaseDecreaseInAccruedLiabilities_693ABBFC5449BE5AAAC8E2A5AEC7E2F5_terseLabel_en-US" xlink:label="lab_us-gaap_IncreaseDecreaseInAccruedLiabilities_693ABBFC5449BE5AAAC8E2A5AEC7E2F5" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">(Decrease) in accrued expenses</link:label>
    <link:label id="lab_us-gaap_IncreaseDecreaseInAccruedLiabilities_693ABBFC5449BE5AAAC8E2A5AEC7E2F5_label_en-US" xlink:label="lab_us-gaap_IncreaseDecreaseInAccruedLiabilities_693ABBFC5449BE5AAAC8E2A5AEC7E2F5" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Increase (Decrease) in Accrued Liabilities</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_IncreaseDecreaseInAccruedLiabilities" xlink:label="loc_us-gaap_IncreaseDecreaseInAccruedLiabilities_693ABBFC5449BE5AAAC8E2A5AEC7E2F5" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncreaseDecreaseInAccruedLiabilities_693ABBFC5449BE5AAAC8E2A5AEC7E2F5" xlink:to="lab_us-gaap_IncreaseDecreaseInAccruedLiabilities_693ABBFC5449BE5AAAC8E2A5AEC7E2F5" xlink:type="arc" />
    <link:label id="lab_us-gaap_IncreaseDecreaseInAccruedTaxesPayable_9A1CC011DE346A75B169E2A5AEC706FE_terseLabel_en-US" xlink:label="lab_us-gaap_IncreaseDecreaseInAccruedTaxesPayable_9A1CC011DE346A75B169E2A5AEC706FE" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Increase (decrease) in taxes, including income taxes</link:label>
    <link:label id="lab_us-gaap_IncreaseDecreaseInAccruedTaxesPayable_9A1CC011DE346A75B169E2A5AEC706FE_label_en-US" xlink:label="lab_us-gaap_IncreaseDecreaseInAccruedTaxesPayable_9A1CC011DE346A75B169E2A5AEC706FE" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Increase (Decrease) in Accrued Taxes Payable</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_IncreaseDecreaseInAccruedTaxesPayable" xlink:label="loc_us-gaap_IncreaseDecreaseInAccruedTaxesPayable_9A1CC011DE346A75B169E2A5AEC706FE" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncreaseDecreaseInAccruedTaxesPayable_9A1CC011DE346A75B169E2A5AEC706FE" xlink:to="lab_us-gaap_IncreaseDecreaseInAccruedTaxesPayable_9A1CC011DE346A75B169E2A5AEC706FE" xlink:type="arc" />
    <link:label id="lab_us-gaap_PensionContributions_C4AA7847F7919E9DE897E2A5AEC7485D_negatedLabel_en-US" xlink:label="lab_us-gaap_PensionContributions_C4AA7847F7919E9DE897E2A5AEC7485D" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xml:lang="en-US">Pension contributions</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PensionContributions" xlink:label="loc_us-gaap_PensionContributions_C4AA7847F7919E9DE897E2A5AEC7485D" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PensionContributions_C4AA7847F7919E9DE897E2A5AEC7485D" xlink:to="lab_us-gaap_PensionContributions_C4AA7847F7919E9DE897E2A5AEC7485D" xlink:type="arc" />
    <link:label id="lab_us-gaap_IncreaseDecreaseInOtherNoncurrentAssets_95E18B5CF4E22E63F26EE2A5AEC77589_negatedLabel_en-US" xlink:label="lab_us-gaap_IncreaseDecreaseInOtherNoncurrentAssets_95E18B5CF4E22E63F26EE2A5AEC77589" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xml:lang="en-US">(Increase) in noncurrent assets</link:label>
    <link:label id="lab_us-gaap_IncreaseDecreaseInOtherNoncurrentAssets_95E18B5CF4E22E63F26EE2A5AEC77589_label_en-US" xlink:label="lab_us-gaap_IncreaseDecreaseInOtherNoncurrentAssets_95E18B5CF4E22E63F26EE2A5AEC77589" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Increase (Decrease) in Other Noncurrent Assets</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_IncreaseDecreaseInOtherNoncurrentAssets" xlink:label="loc_us-gaap_IncreaseDecreaseInOtherNoncurrentAssets_95E18B5CF4E22E63F26EE2A5AEC77589" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncreaseDecreaseInOtherNoncurrentAssets_95E18B5CF4E22E63F26EE2A5AEC77589" xlink:to="lab_us-gaap_IncreaseDecreaseInOtherNoncurrentAssets_95E18B5CF4E22E63F26EE2A5AEC77589" xlink:type="arc" />
    <link:label id="lab_us-gaap_IncreaseDecreaseInOtherNoncurrentLiabilities_90C3F61B83C2505509ECE2A5AEC7C322_terseLabel_en-US" xlink:label="lab_us-gaap_IncreaseDecreaseInOtherNoncurrentLiabilities_90C3F61B83C2505509ECE2A5AEC7C322" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">(Decrease) in noncurrent liabilities</link:label>
    <link:label id="lab_us-gaap_IncreaseDecreaseInOtherNoncurrentLiabilities_90C3F61B83C2505509ECE2A5AEC7C322_label_en-US" xlink:label="lab_us-gaap_IncreaseDecreaseInOtherNoncurrentLiabilities_90C3F61B83C2505509ECE2A5AEC7C322" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Increase (Decrease) in Other Noncurrent Liabilities</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_IncreaseDecreaseInOtherNoncurrentLiabilities" xlink:label="loc_us-gaap_IncreaseDecreaseInOtherNoncurrentLiabilities_90C3F61B83C2505509ECE2A5AEC7C322" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncreaseDecreaseInOtherNoncurrentLiabilities_90C3F61B83C2505509ECE2A5AEC7C322" xlink:to="lab_us-gaap_IncreaseDecreaseInOtherNoncurrentLiabilities_90C3F61B83C2505509ECE2A5AEC7C322" xlink:type="arc" />
    <link:label id="lab_us-gaap_NetCashProvidedByUsedInOperatingActivities_B443CB12575C6EFCE05AE2A5AEC7D755_totalLabel_en-US" xlink:label="lab_us-gaap_NetCashProvidedByUsedInOperatingActivities_B443CB12575C6EFCE05AE2A5AEC7D755" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Cash provided from (used for) operations</link:label>
    <link:label id="lab_us-gaap_NetCashProvidedByUsedInOperatingActivities_B443CB12575C6EFCE05AE2A5AEC7D755_label_en-US" xlink:label="lab_us-gaap_NetCashProvidedByUsedInOperatingActivities_B443CB12575C6EFCE05AE2A5AEC7D755" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Net Cash Provided by (Used in) Operating Activities</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_NetCashProvidedByUsedInOperatingActivities" xlink:label="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_B443CB12575C6EFCE05AE2A5AEC7D755" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_B443CB12575C6EFCE05AE2A5AEC7D755" xlink:to="lab_us-gaap_NetCashProvidedByUsedInOperatingActivities_B443CB12575C6EFCE05AE2A5AEC7D755" xlink:type="arc" />
    <link:label id="lab_us-gaap_NetCashProvidedByUsedInFinancingActivitiesContinuingOperationsAbstract_0B544AD7318EFA7DB1D9E2A5AEC70AB8_terseLabel_en-US" xlink:label="lab_us-gaap_NetCashProvidedByUsedInFinancingActivitiesContinuingOperationsAbstract_0B544AD7318EFA7DB1D9E2A5AEC70AB8" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Financing Activities</link:label>
    <link:label id="lab_us-gaap_NetCashProvidedByUsedInFinancingActivitiesContinuingOperationsAbstract_0B544AD7318EFA7DB1D9E2A5AEC70AB8_label_en-US" xlink:label="lab_us-gaap_NetCashProvidedByUsedInFinancingActivitiesContinuingOperationsAbstract_0B544AD7318EFA7DB1D9E2A5AEC70AB8" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Net Cash Provided by (Used in) Financing Activities, Continuing Operations [Abstract]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_NetCashProvidedByUsedInFinancingActivitiesContinuingOperationsAbstract" xlink:label="loc_us-gaap_NetCashProvidedByUsedInFinancingActivitiesContinuingOperationsAbstract_0B544AD7318EFA7DB1D9E2A5AEC70AB8" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivitiesContinuingOperationsAbstract_0B544AD7318EFA7DB1D9E2A5AEC70AB8" xlink:to="lab_us-gaap_NetCashProvidedByUsedInFinancingActivitiesContinuingOperationsAbstract_0B544AD7318EFA7DB1D9E2A5AEC70AB8" xlink:type="arc" />
    <link:label id="lab_us-gaap_ProceedsFromRepaymentsOfShortTermDebtMaturingInThreeMonthsOrLess_A44DD58536C9E47A6F8AE2A5AEC7B185_terseLabel_en-US" xlink:label="lab_us-gaap_ProceedsFromRepaymentsOfShortTermDebtMaturingInThreeMonthsOrLess_A44DD58536C9E47A6F8AE2A5AEC7B185" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Net change in short-term borrowings (original maturities of three months or less)</link:label>
    <link:label id="lab_us-gaap_ProceedsFromRepaymentsOfShortTermDebtMaturingInThreeMonthsOrLess_A44DD58536C9E47A6F8AE2A5AEC7B185_label_en-US" xlink:label="lab_us-gaap_ProceedsFromRepaymentsOfShortTermDebtMaturingInThreeMonthsOrLess_A44DD58536C9E47A6F8AE2A5AEC7B185" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Proceeds from (Repayments of) Short-term Debt, Maturing in Three Months or Less</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ProceedsFromRepaymentsOfShortTermDebtMaturingInThreeMonthsOrLess" xlink:label="loc_us-gaap_ProceedsFromRepaymentsOfShortTermDebtMaturingInThreeMonthsOrLess_A44DD58536C9E47A6F8AE2A5AEC7B185" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ProceedsFromRepaymentsOfShortTermDebtMaturingInThreeMonthsOrLess_A44DD58536C9E47A6F8AE2A5AEC7B185" xlink:to="lab_us-gaap_ProceedsFromRepaymentsOfShortTermDebtMaturingInThreeMonthsOrLess_A44DD58536C9E47A6F8AE2A5AEC7B185" xlink:type="arc" />
    <link:label id="lab_us-gaap_ProceedsFromIssuanceOfLongTermDebt_0D81B025C00537168D0FE2A5AEC7DA9F_terseLabel_en-US" xlink:label="lab_us-gaap_ProceedsFromIssuanceOfLongTermDebt_0D81B025C00537168D0FE2A5AEC7DA9F" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Additions to debt (original maturities greater than three months) (P)</link:label>
    <link:label id="lab_us-gaap_ProceedsFromIssuanceOfLongTermDebt_0D81B025C00537168D0FE2A5AEC7DA9F_label_en-US" xlink:label="lab_us-gaap_ProceedsFromIssuanceOfLongTermDebt_0D81B025C00537168D0FE2A5AEC7DA9F" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Proceeds from Issuance of Long-term Debt</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ProceedsFromIssuanceOfLongTermDebt" xlink:label="loc_us-gaap_ProceedsFromIssuanceOfLongTermDebt_0D81B025C00537168D0FE2A5AEC7DA9F" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ProceedsFromIssuanceOfLongTermDebt_0D81B025C00537168D0FE2A5AEC7DA9F" xlink:to="lab_us-gaap_ProceedsFromIssuanceOfLongTermDebt_0D81B025C00537168D0FE2A5AEC7DA9F" xlink:type="arc" />
    <link:label id="lab_us-gaap_RepaymentsOfLongTermDebt_3FC8EA4959471A647B42E2A5AEC7EA50_negatedLabel_en-US" xlink:label="lab_us-gaap_RepaymentsOfLongTermDebt_3FC8EA4959471A647B42E2A5AEC7EA50" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xml:lang="en-US">Payments on debt (original maturities greater than three months) (P)</link:label>
    <link:label id="lab_us-gaap_RepaymentsOfLongTermDebt_3FC8EA4959471A647B42E2A5AEC7EA50_label_en-US" xlink:label="lab_us-gaap_RepaymentsOfLongTermDebt_3FC8EA4959471A647B42E2A5AEC7EA50" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Repayments of Long-term Debt</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RepaymentsOfLongTermDebt" xlink:label="loc_us-gaap_RepaymentsOfLongTermDebt_3FC8EA4959471A647B42E2A5AEC7EA50" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RepaymentsOfLongTermDebt_3FC8EA4959471A647B42E2A5AEC7EA50" xlink:to="lab_us-gaap_RepaymentsOfLongTermDebt_3FC8EA4959471A647B42E2A5AEC7EA50" xlink:type="arc" />
    <link:label id="lab_us-gaap_PaymentsOfDebtExtinguishmentCosts_217A371EBCEC5FE7E84AE2A5AEC76E28_negatedTerseLabel_en-US" xlink:label="lab_us-gaap_PaymentsOfDebtExtinguishmentCosts_217A371EBCEC5FE7E84AE2A5AEC76E28" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:type="resource" xml:lang="en-US">Premiums paid on early redemption of debt (A and P)</link:label>
    <link:label id="lab_us-gaap_PaymentsOfDebtExtinguishmentCosts_217A371EBCEC5FE7E84AE2A5AEC76E28_label_en-US" xlink:label="lab_us-gaap_PaymentsOfDebtExtinguishmentCosts_217A371EBCEC5FE7E84AE2A5AEC76E28" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Payment for Debt Extinguishment or Debt Prepayment Cost</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PaymentsOfDebtExtinguishmentCosts" xlink:label="loc_us-gaap_PaymentsOfDebtExtinguishmentCosts_217A371EBCEC5FE7E84AE2A5AEC76E28" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PaymentsOfDebtExtinguishmentCosts_217A371EBCEC5FE7E84AE2A5AEC76E28" xlink:to="lab_us-gaap_PaymentsOfDebtExtinguishmentCosts_217A371EBCEC5FE7E84AE2A5AEC76E28" xlink:type="arc" />
    <link:label id="lab_us-gaap_PaymentsOfOrdinaryDividends_D0F6C63B23DA41BB7AF6E2A5AEC76602_negatedLabel_en-US" xlink:label="lab_us-gaap_PaymentsOfOrdinaryDividends_D0F6C63B23DA41BB7AF6E2A5AEC76602" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xml:lang="en-US">Dividends paid to shareholders</link:label>
    <link:label id="lab_us-gaap_PaymentsOfOrdinaryDividends_D0F6C63B23DA41BB7AF6E2A5AEC76602_label_en-US" xlink:label="lab_us-gaap_PaymentsOfOrdinaryDividends_D0F6C63B23DA41BB7AF6E2A5AEC76602" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Payments of Ordinary Dividends</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PaymentsOfOrdinaryDividends" xlink:label="loc_us-gaap_PaymentsOfOrdinaryDividends_D0F6C63B23DA41BB7AF6E2A5AEC76602" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PaymentsOfOrdinaryDividends_D0F6C63B23DA41BB7AF6E2A5AEC76602" xlink:to="lab_us-gaap_PaymentsOfOrdinaryDividends_D0F6C63B23DA41BB7AF6E2A5AEC76602" xlink:type="arc" />
    <link:label id="lab_us-gaap_PaymentsOfDistributionsToAffiliates_2900BC38C445CA157BFCE2A5AEC798D2_negatedLabel_en-US" xlink:label="lab_us-gaap_PaymentsOfDistributionsToAffiliates_2900BC38C445CA157BFCE2A5AEC798D2" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xml:lang="en-US">Distributions to noncontrolling interests</link:label>
    <link:label id="lab_us-gaap_PaymentsOfDistributionsToAffiliates_2900BC38C445CA157BFCE2A5AEC798D2_label_en-US" xlink:label="lab_us-gaap_PaymentsOfDistributionsToAffiliates_2900BC38C445CA157BFCE2A5AEC798D2" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Payments of Distributions to Affiliates</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PaymentsOfDistributionsToAffiliates" xlink:label="loc_us-gaap_PaymentsOfDistributionsToAffiliates_2900BC38C445CA157BFCE2A5AEC798D2" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PaymentsOfDistributionsToAffiliates_2900BC38C445CA157BFCE2A5AEC798D2" xlink:to="lab_us-gaap_PaymentsOfDistributionsToAffiliates_2900BC38C445CA157BFCE2A5AEC798D2" xlink:type="arc" />
    <link:label id="lab_us-gaap_ProceedsFromMinorityShareholders_F29CC10B159F0D5AEE46E2A5AEC70059_terseLabel_en-US" xlink:label="lab_us-gaap_ProceedsFromMinorityShareholders_F29CC10B159F0D5AEE46E2A5AEC70059" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Contributions from noncontrolling interests</link:label>
    <link:label id="lab_us-gaap_ProceedsFromMinorityShareholders_F29CC10B159F0D5AEE46E2A5AEC70059_label_en-US" xlink:label="lab_us-gaap_ProceedsFromMinorityShareholders_F29CC10B159F0D5AEE46E2A5AEC70059" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Proceeds from Noncontrolling Interests</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ProceedsFromMinorityShareholders" xlink:label="loc_us-gaap_ProceedsFromMinorityShareholders_F29CC10B159F0D5AEE46E2A5AEC70059" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ProceedsFromMinorityShareholders_F29CC10B159F0D5AEE46E2A5AEC70059" xlink:to="lab_us-gaap_ProceedsFromMinorityShareholders_F29CC10B159F0D5AEE46E2A5AEC70059" xlink:type="arc" />
    <link:label id="lab_arnc_CashTransferredFromAffiliatesAtSeparation_D7885A956E870003ED61E2A5AEC7EC99_terseLabel_en-US" xlink:label="lab_arnc_CashTransferredFromAffiliatesAtSeparation_D7885A956E870003ED61E2A5AEC7EC99" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Net cash transferred from Alcoa Corporation at separation</link:label>
    <link:label id="lab_arnc_CashTransferredFromAffiliatesAtSeparation_D7885A956E870003ED61E2A5AEC7EC99_label_en-US" xlink:label="lab_arnc_CashTransferredFromAffiliatesAtSeparation_D7885A956E870003ED61E2A5AEC7EC99" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Cash Transferred From Affiliates At Separation</link:label>
    <link:label id="lab_arnc_CashTransferredFromAffiliatesAtSeparation_D7885A956E870003ED61E2A5AEC7EC99_documentation_en-US" xlink:label="lab_arnc_CashTransferredFromAffiliatesAtSeparation_D7885A956E870003ED61E2A5AEC7EC99" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Cash transferred from affiliates at separation.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_CashTransferredFromAffiliatesAtSeparation" xlink:label="loc_arnc_CashTransferredFromAffiliatesAtSeparation_D7885A956E870003ED61E2A5AEC7EC99" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_CashTransferredFromAffiliatesAtSeparation_D7885A956E870003ED61E2A5AEC7EC99" xlink:to="lab_arnc_CashTransferredFromAffiliatesAtSeparation_D7885A956E870003ED61E2A5AEC7EC99" xlink:type="arc" />
    <link:label id="lab_us-gaap_ProceedsFromPaymentsForOtherFinancingActivities_8D55364B72741D318C54E2A5AEC73430_terseLabel_en-US" xlink:label="lab_us-gaap_ProceedsFromPaymentsForOtherFinancingActivities_8D55364B72741D318C54E2A5AEC73430" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Other</link:label>
    <link:label id="lab_us-gaap_ProceedsFromPaymentsForOtherFinancingActivities_8D55364B72741D318C54E2A5AEC73430_label_en-US" xlink:label="lab_us-gaap_ProceedsFromPaymentsForOtherFinancingActivities_8D55364B72741D318C54E2A5AEC73430" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Proceeds from (Payments for) Other Financing Activities</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ProceedsFromPaymentsForOtherFinancingActivities" xlink:label="loc_us-gaap_ProceedsFromPaymentsForOtherFinancingActivities_8D55364B72741D318C54E2A5AEC73430" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ProceedsFromPaymentsForOtherFinancingActivities_8D55364B72741D318C54E2A5AEC73430" xlink:to="lab_us-gaap_ProceedsFromPaymentsForOtherFinancingActivities_8D55364B72741D318C54E2A5AEC73430" xlink:type="arc" />
    <link:label id="lab_us-gaap_NetCashProvidedByUsedInFinancingActivities_15F88612F868DFD1B920E2A5AEC76FEA_totalLabel_en-US" xlink:label="lab_us-gaap_NetCashProvidedByUsedInFinancingActivities_15F88612F868DFD1B920E2A5AEC76FEA" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Cash used for financing activities</link:label>
    <link:label id="lab_us-gaap_NetCashProvidedByUsedInFinancingActivities_15F88612F868DFD1B920E2A5AEC76FEA_label_en-US" xlink:label="lab_us-gaap_NetCashProvidedByUsedInFinancingActivities_15F88612F868DFD1B920E2A5AEC76FEA" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Net Cash Provided by (Used in) Financing Activities</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_NetCashProvidedByUsedInFinancingActivities" xlink:label="loc_us-gaap_NetCashProvidedByUsedInFinancingActivities_15F88612F868DFD1B920E2A5AEC76FEA" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivities_15F88612F868DFD1B920E2A5AEC76FEA" xlink:to="lab_us-gaap_NetCashProvidedByUsedInFinancingActivities_15F88612F868DFD1B920E2A5AEC76FEA" xlink:type="arc" />
    <link:label id="lab_us-gaap_NetCashProvidedByUsedInInvestingActivitiesContinuingOperationsAbstract_CBB8C3CB357A539FE0B0E2A5AEC7E827_terseLabel_en-US" xlink:label="lab_us-gaap_NetCashProvidedByUsedInInvestingActivitiesContinuingOperationsAbstract_CBB8C3CB357A539FE0B0E2A5AEC7E827" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Investing Activities</link:label>
    <link:label id="lab_us-gaap_NetCashProvidedByUsedInInvestingActivitiesContinuingOperationsAbstract_CBB8C3CB357A539FE0B0E2A5AEC7E827_label_en-US" xlink:label="lab_us-gaap_NetCashProvidedByUsedInInvestingActivitiesContinuingOperationsAbstract_CBB8C3CB357A539FE0B0E2A5AEC7E827" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Net Cash Provided by (Used in) Investing Activities, Continuing Operations [Abstract]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_NetCashProvidedByUsedInInvestingActivitiesContinuingOperationsAbstract" xlink:label="loc_us-gaap_NetCashProvidedByUsedInInvestingActivitiesContinuingOperationsAbstract_CBB8C3CB357A539FE0B0E2A5AEC7E827" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_NetCashProvidedByUsedInInvestingActivitiesContinuingOperationsAbstract_CBB8C3CB357A539FE0B0E2A5AEC7E827" xlink:to="lab_us-gaap_NetCashProvidedByUsedInInvestingActivitiesContinuingOperationsAbstract_CBB8C3CB357A539FE0B0E2A5AEC7E827" xlink:type="arc" />
    <link:label id="lab_us-gaap_PaymentsToAcquirePropertyPlantAndEquipment_75D2F34470A32414FBCEE2A5AEC790DA_negatedLabel_en-US" xlink:label="lab_us-gaap_PaymentsToAcquirePropertyPlantAndEquipment_75D2F34470A32414FBCEE2A5AEC790DA" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xml:lang="en-US">Capital expenditures</link:label>
    <link:label id="lab_us-gaap_PaymentsToAcquirePropertyPlantAndEquipment_75D2F34470A32414FBCEE2A5AEC790DA_label_en-US" xlink:label="lab_us-gaap_PaymentsToAcquirePropertyPlantAndEquipment_75D2F34470A32414FBCEE2A5AEC790DA" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Payments to Acquire Property, Plant, and Equipment</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PaymentsToAcquirePropertyPlantAndEquipment" xlink:label="loc_us-gaap_PaymentsToAcquirePropertyPlantAndEquipment_75D2F34470A32414FBCEE2A5AEC790DA" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PaymentsToAcquirePropertyPlantAndEquipment_75D2F34470A32414FBCEE2A5AEC790DA" xlink:to="lab_us-gaap_PaymentsToAcquirePropertyPlantAndEquipment_75D2F34470A32414FBCEE2A5AEC790DA" xlink:type="arc" />
    <link:label id="lab_us-gaap_PaymentsToAcquireBusinessesNetOfCashAcquired_83B195FCBA5CFF789987E2A5AEC73217_negatedLabel_en-US" xlink:label="lab_us-gaap_PaymentsToAcquireBusinessesNetOfCashAcquired_83B195FCBA5CFF789987E2A5AEC73217" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xml:lang="en-US">Acquisitions, net of cash acquired (S)</link:label>
    <link:label id="lab_us-gaap_PaymentsToAcquireBusinessesNetOfCashAcquired_83B195FCBA5CFF789987E2A5AEC73217_label_en-US" xlink:label="lab_us-gaap_PaymentsToAcquireBusinessesNetOfCashAcquired_83B195FCBA5CFF789987E2A5AEC73217" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Payments to Acquire Businesses, Net of Cash Acquired</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PaymentsToAcquireBusinessesNetOfCashAcquired" xlink:label="loc_us-gaap_PaymentsToAcquireBusinessesNetOfCashAcquired_83B195FCBA5CFF789987E2A5AEC73217" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PaymentsToAcquireBusinessesNetOfCashAcquired_83B195FCBA5CFF789987E2A5AEC73217" xlink:to="lab_us-gaap_PaymentsToAcquireBusinessesNetOfCashAcquired_83B195FCBA5CFF789987E2A5AEC73217" xlink:type="arc" />
    <link:label id="lab_us-gaap_PaymentsForProceedsFromProductiveAssets_1F42ABAFF6A8C0762477E2A5AEC79707_negatedLabel_en-US" xlink:label="lab_us-gaap_PaymentsForProceedsFromProductiveAssets_1F42ABAFF6A8C0762477E2A5AEC79707" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xml:lang="en-US">Proceeds from the sale of assets and businesses (S)</link:label>
    <link:label id="lab_us-gaap_PaymentsForProceedsFromProductiveAssets_1F42ABAFF6A8C0762477E2A5AEC79707_label_en-US" xlink:label="lab_us-gaap_PaymentsForProceedsFromProductiveAssets_1F42ABAFF6A8C0762477E2A5AEC79707" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Payments for (Proceeds from) Productive Assets</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PaymentsForProceedsFromProductiveAssets" xlink:label="loc_us-gaap_PaymentsForProceedsFromProductiveAssets_1F42ABAFF6A8C0762477E2A5AEC79707" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PaymentsForProceedsFromProductiveAssets_1F42ABAFF6A8C0762477E2A5AEC79707" xlink:to="lab_us-gaap_PaymentsForProceedsFromProductiveAssets_1F42ABAFF6A8C0762477E2A5AEC79707" xlink:type="arc" />
    <link:label id="lab_us-gaap_ProceedsFromSaleMaturityAndCollectionsOfInvestments_88C760469C2D55B7D329E2A5AEC765CE_terseLabel_en-US" xlink:label="lab_us-gaap_ProceedsFromSaleMaturityAndCollectionsOfInvestments_88C760469C2D55B7D329E2A5AEC765CE" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Sales of investments (S and V)</link:label>
    <link:label id="lab_us-gaap_ProceedsFromSaleMaturityAndCollectionsOfInvestments_88C760469C2D55B7D329E2A5AEC765CE_label_en-US" xlink:label="lab_us-gaap_ProceedsFromSaleMaturityAndCollectionsOfInvestments_88C760469C2D55B7D329E2A5AEC765CE" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Proceeds from Sale, Maturity and Collection of Investments</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ProceedsFromSaleMaturityAndCollectionsOfInvestments" xlink:label="loc_us-gaap_ProceedsFromSaleMaturityAndCollectionsOfInvestments_88C760469C2D55B7D329E2A5AEC765CE" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ProceedsFromSaleMaturityAndCollectionsOfInvestments_88C760469C2D55B7D329E2A5AEC765CE" xlink:to="lab_us-gaap_ProceedsFromSaleMaturityAndCollectionsOfInvestments_88C760469C2D55B7D329E2A5AEC765CE" xlink:type="arc" />
    <link:label id="lab_us-gaap_ProceedsFromSaleOfFinanceReceivables_DD6B66FCA2B50D7DB7D3E2A5AEC758C5_terseLabel_en-US" xlink:label="lab_us-gaap_ProceedsFromSaleOfFinanceReceivables_DD6B66FCA2B50D7DB7D3E2A5AEC758C5" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Cash receipts from sold receivables (A and L)</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ProceedsFromSaleOfFinanceReceivables" xlink:label="loc_us-gaap_ProceedsFromSaleOfFinanceReceivables_DD6B66FCA2B50D7DB7D3E2A5AEC758C5" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ProceedsFromSaleOfFinanceReceivables_DD6B66FCA2B50D7DB7D3E2A5AEC758C5" xlink:to="lab_us-gaap_ProceedsFromSaleOfFinanceReceivables_DD6B66FCA2B50D7DB7D3E2A5AEC758C5" xlink:type="arc" />
    <link:label id="lab_us-gaap_PaymentsForProceedsFromOtherInvestingActivities_74E46E6F501AD54EAEC1E2A5AEC776D8_negatedLabel_en-US" xlink:label="lab_us-gaap_PaymentsForProceedsFromOtherInvestingActivities_74E46E6F501AD54EAEC1E2A5AEC776D8" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xml:lang="en-US">Other (V)</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PaymentsForProceedsFromOtherInvestingActivities" xlink:label="loc_us-gaap_PaymentsForProceedsFromOtherInvestingActivities_74E46E6F501AD54EAEC1E2A5AEC776D8" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PaymentsForProceedsFromOtherInvestingActivities_74E46E6F501AD54EAEC1E2A5AEC776D8" xlink:to="lab_us-gaap_PaymentsForProceedsFromOtherInvestingActivities_74E46E6F501AD54EAEC1E2A5AEC776D8" xlink:type="arc" />
    <link:label id="lab_us-gaap_NetCashProvidedByUsedInInvestingActivities_3B86645455C04EDE4215E2A5AEC72BE5_totalLabel_en-US" xlink:label="lab_us-gaap_NetCashProvidedByUsedInInvestingActivities_3B86645455C04EDE4215E2A5AEC72BE5" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Cash provided from investing activities</link:label>
    <link:label id="lab_us-gaap_NetCashProvidedByUsedInInvestingActivities_3B86645455C04EDE4215E2A5AEC72BE5_label_en-US" xlink:label="lab_us-gaap_NetCashProvidedByUsedInInvestingActivities_3B86645455C04EDE4215E2A5AEC72BE5" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Net Cash Provided by (Used in) Investing Activities</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_NetCashProvidedByUsedInInvestingActivities" xlink:label="loc_us-gaap_NetCashProvidedByUsedInInvestingActivities_3B86645455C04EDE4215E2A5AEC72BE5" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_NetCashProvidedByUsedInInvestingActivities_3B86645455C04EDE4215E2A5AEC72BE5" xlink:to="lab_us-gaap_NetCashProvidedByUsedInInvestingActivities_3B86645455C04EDE4215E2A5AEC72BE5" xlink:type="arc" />
    <link:label id="lab_us-gaap_EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_05AA1CE593DBD89DB2A5E2A5AEC72AD7_terseLabel_en-US" xlink:label="lab_us-gaap_EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_05AA1CE593DBD89DB2A5E2A5AEC72AD7" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Effect of exchange rate changes on cash, cash equivalents and restricted cash</link:label>
    <link:label id="lab_us-gaap_EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_05AA1CE593DBD89DB2A5E2A5AEC72AD7_label_en-US" xlink:label="lab_us-gaap_EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_05AA1CE593DBD89DB2A5E2A5AEC72AD7" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Effect of Exchange Rate on Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents" xlink:label="loc_us-gaap_EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_05AA1CE593DBD89DB2A5E2A5AEC72AD7" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_05AA1CE593DBD89DB2A5E2A5AEC72AD7" xlink:to="lab_us-gaap_EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_05AA1CE593DBD89DB2A5E2A5AEC72AD7" xlink:type="arc" />
    <link:label id="lab_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseExcludingExchangeRateEffect_936F7A52460D07D9D6FCE2A5AEC79D62_totalLabel_en-US" xlink:label="lab_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseExcludingExchangeRateEffect_936F7A52460D07D9D6FCE2A5AEC79D62" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Net change in cash, cash equivalents and restricted cash (A)</link:label>
    <link:label id="lab_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseExcludingExchangeRateEffect_936F7A52460D07D9D6FCE2A5AEC79D62_label_en-US" xlink:label="lab_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseExcludingExchangeRateEffect_936F7A52460D07D9D6FCE2A5AEC79D62" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents, Period Increase (Decrease), Excluding Exchange Rate Effect</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseExcludingExchangeRateEffect" xlink:label="loc_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseExcludingExchangeRateEffect_936F7A52460D07D9D6FCE2A5AEC79D62" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseExcludingExchangeRateEffect_936F7A52460D07D9D6FCE2A5AEC79D62" xlink:to="lab_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseExcludingExchangeRateEffect_936F7A52460D07D9D6FCE2A5AEC79D62" xlink:type="arc" />
    <link:label id="lab_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_53D2BD90193E39ECCCF2E2A5AEC7197D_periodStartLabel_en-US" xlink:label="lab_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_53D2BD90193E39ECCCF2E2A5AEC7197D" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel" xlink:type="resource" xml:lang="en-US">Cash, cash equivalents and restricted cash at beginning of year (A)</link:label>
    <link:label id="lab_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_53D2BD90193E39ECCCF2E2A5AEC7197D_label_en-US" xlink:label="lab_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_53D2BD90193E39ECCCF2E2A5AEC7197D" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents" xlink:label="loc_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_53D2BD90193E39ECCCF2E2A5AEC7197D" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_53D2BD90193E39ECCCF2E2A5AEC7197D" xlink:to="lab_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_53D2BD90193E39ECCCF2E2A5AEC7197D" xlink:type="arc" />
    <link:label id="lab_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_4A3CF5DCFB317908324FE2A5AEC76EE4_periodEndLabel_en-US" xlink:label="lab_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_4A3CF5DCFB317908324FE2A5AEC76EE4" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel" xlink:type="resource" xml:lang="en-US">Cash, cash equivalents and restricted cash at end of year (A)</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents" xlink:label="loc_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_4A3CF5DCFB317908324FE2A5AEC76EE4" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_4A3CF5DCFB317908324FE2A5AEC76EE4" xlink:to="lab_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_4A3CF5DCFB317908324FE2A5AEC76EE4" xlink:type="arc" />
    <link:label id="lab_us-gaap_CorporateMember_7BBECD9168179B13D8DBBE4DB9E2F86D_terseLabel_en-US" xlink:label="lab_us-gaap_CorporateMember_7BBECD9168179B13D8DBBE4DB9E2F86D" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Corporate Segment</link:label>
    <link:label id="lab_us-gaap_CorporateMember_7BBECD9168179B13D8DBBE4DB9E2F86D_label_en-US" xlink:label="lab_us-gaap_CorporateMember_7BBECD9168179B13D8DBBE4DB9E2F86D" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Corporate Segment [Member]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_CorporateMember" xlink:label="loc_us-gaap_CorporateMember_7BBECD9168179B13D8DBBE4DB9E2F86D" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CorporateMember_7BBECD9168179B13D8DBBE4DB9E2F86D" xlink:to="lab_us-gaap_CorporateMember_7BBECD9168179B13D8DBBE4DB9E2F86D" xlink:type="arc" />
    <link:label id="lab_arnc_FusinaItalyMember_7736B87F38B3AB4FCEE1BE4DB9E37F7A_terseLabel_en-US" xlink:label="lab_arnc_FusinaItalyMember_7736B87F38B3AB4FCEE1BE4DB9E37F7A" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Fusina Italy</link:label>
    <link:label id="lab_arnc_FusinaItalyMember_7736B87F38B3AB4FCEE1BE4DB9E37F7A_label_en-US" xlink:label="lab_arnc_FusinaItalyMember_7736B87F38B3AB4FCEE1BE4DB9E37F7A" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Fusina Italy [Member]</link:label>
    <link:label id="lab_arnc_FusinaItalyMember_7736B87F38B3AB4FCEE1BE4DB9E37F7A_documentation_en-US" xlink:label="lab_arnc_FusinaItalyMember_7736B87F38B3AB4FCEE1BE4DB9E37F7A" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Fusina Italy.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_FusinaItalyMember" xlink:label="loc_arnc_FusinaItalyMember_7736B87F38B3AB4FCEE1BE4DB9E37F7A" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_FusinaItalyMember_7736B87F38B3AB4FCEE1BE4DB9E37F7A" xlink:to="lab_arnc_FusinaItalyMember_7736B87F38B3AB4FCEE1BE4DB9E37F7A" xlink:type="arc" />
    <link:label id="lab_arnc_OtherExitCostsMember_E4395E6C01BF4BF508EABE4DB9E49AFF_verboseLabel_en-US" xlink:label="lab_arnc_OtherExitCostsMember_E4395E6C01BF4BF508EABE4DB9E49AFF" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Other Exit Costs</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_OtherExitCostsMember" xlink:label="loc_arnc_OtherExitCostsMember_E4395E6C01BF4BF508EABE4DB9E49AFF" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_OtherExitCostsMember_E4395E6C01BF4BF508EABE4DB9E49AFF" xlink:to="lab_arnc_OtherExitCostsMember_E4395E6C01BF4BF508EABE4DB9E49AFF" xlink:type="arc" />
    <link:label id="lab_arnc_ReversalOfForfeitedExecutiveStockCompensationMember_662DA449A854DBA63470BE4DB9E4ED54_terseLabel_en-US" xlink:label="lab_arnc_ReversalOfForfeitedExecutiveStockCompensationMember_662DA449A854DBA63470BE4DB9E4ED54" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Reversal Of Forfeited Executive Stock Compensation</link:label>
    <link:label id="lab_arnc_ReversalOfForfeitedExecutiveStockCompensationMember_662DA449A854DBA63470BE4DB9E4ED54_label_en-US" xlink:label="lab_arnc_ReversalOfForfeitedExecutiveStockCompensationMember_662DA449A854DBA63470BE4DB9E4ED54" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Reversal Of Forfeited Executive Stock Compensation [Member]</link:label>
    <link:label id="lab_arnc_ReversalOfForfeitedExecutiveStockCompensationMember_662DA449A854DBA63470BE4DB9E4ED54_documentation_en-US" xlink:label="lab_arnc_ReversalOfForfeitedExecutiveStockCompensationMember_662DA449A854DBA63470BE4DB9E4ED54" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Reversal of forfeited executive stock compensation.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_ReversalOfForfeitedExecutiveStockCompensationMember" xlink:label="loc_arnc_ReversalOfForfeitedExecutiveStockCompensationMember_662DA449A854DBA63470BE4DB9E4ED54" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_ReversalOfForfeitedExecutiveStockCompensationMember_662DA449A854DBA63470BE4DB9E4ED54" xlink:to="lab_arnc_ReversalOfForfeitedExecutiveStockCompensationMember_662DA449A854DBA63470BE4DB9E4ED54" xlink:type="arc" />
    <link:label id="lab_arnc_OtherMiscellaneousChargesMember_EB01DC8576CB869D9314BE4DB9E51112_terseLabel_en-US" xlink:label="lab_arnc_OtherMiscellaneousChargesMember_EB01DC8576CB869D9314BE4DB9E51112" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Other Miscellaneous Charges</link:label>
    <link:label id="lab_arnc_OtherMiscellaneousChargesMember_EB01DC8576CB869D9314BE4DB9E51112_label_en-US" xlink:label="lab_arnc_OtherMiscellaneousChargesMember_EB01DC8576CB869D9314BE4DB9E51112" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Other Miscellaneous Charges [Member]</link:label>
    <link:label id="lab_arnc_OtherMiscellaneousChargesMember_EB01DC8576CB869D9314BE4DB9E51112_documentation_en-US" xlink:label="lab_arnc_OtherMiscellaneousChargesMember_EB01DC8576CB869D9314BE4DB9E51112" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Other miscellaneous charges.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_OtherMiscellaneousChargesMember" xlink:label="loc_arnc_OtherMiscellaneousChargesMember_EB01DC8576CB869D9314BE4DB9E51112" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_OtherMiscellaneousChargesMember_EB01DC8576CB869D9314BE4DB9E51112" xlink:to="lab_arnc_OtherMiscellaneousChargesMember_EB01DC8576CB869D9314BE4DB9E51112" xlink:type="arc" />
    <link:label id="lab_arnc_OtherAdjustmentsMember_C00FA0AB513486D06CD8BE4DB9E59238_terseLabel_en-US" xlink:label="lab_arnc_OtherAdjustmentsMember_C00FA0AB513486D06CD8BE4DB9E59238" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Other Adjustments</link:label>
    <link:label id="lab_arnc_OtherAdjustmentsMember_C00FA0AB513486D06CD8BE4DB9E59238_label_en-US" xlink:label="lab_arnc_OtherAdjustmentsMember_C00FA0AB513486D06CD8BE4DB9E59238" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Other Adjustments [Member]</link:label>
    <link:label id="lab_arnc_OtherAdjustmentsMember_C00FA0AB513486D06CD8BE4DB9E59238_documentation_en-US" xlink:label="lab_arnc_OtherAdjustmentsMember_C00FA0AB513486D06CD8BE4DB9E59238" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Other adjustments.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_OtherAdjustmentsMember" xlink:label="loc_arnc_OtherAdjustmentsMember_C00FA0AB513486D06CD8BE4DB9E59238" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_OtherAdjustmentsMember_C00FA0AB513486D06CD8BE4DB9E59238" xlink:to="lab_arnc_OtherAdjustmentsMember_C00FA0AB513486D06CD8BE4DB9E59238" xlink:type="arc" />
    <link:label id="lab_arnc_RestructuringProgramsLayoffsTwoThousandSeventeenMember_EAE5C0BD66E8E231CAAFBE4DB9E55558_terseLabel_en-US" xlink:label="lab_arnc_RestructuringProgramsLayoffsTwoThousandSeventeenMember_EAE5C0BD66E8E231CAAFBE4DB9E55558" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Restructuring Programs Layoffs Two Thousand Seventeen</link:label>
    <link:label id="lab_arnc_RestructuringProgramsLayoffsTwoThousandSeventeenMember_EAE5C0BD66E8E231CAAFBE4DB9E55558_label_en-US" xlink:label="lab_arnc_RestructuringProgramsLayoffsTwoThousandSeventeenMember_EAE5C0BD66E8E231CAAFBE4DB9E55558" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Restructuring Programs Layoffs Two Thousand Seventeen [Member]</link:label>
    <link:label id="lab_arnc_RestructuringProgramsLayoffsTwoThousandSeventeenMember_EAE5C0BD66E8E231CAAFBE4DB9E55558_documentation_en-US" xlink:label="lab_arnc_RestructuringProgramsLayoffsTwoThousandSeventeenMember_EAE5C0BD66E8E231CAAFBE4DB9E55558" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Restructuring programs layoffs two thousand seventeen.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_RestructuringProgramsLayoffsTwoThousandSeventeenMember" xlink:label="loc_arnc_RestructuringProgramsLayoffsTwoThousandSeventeenMember_EAE5C0BD66E8E231CAAFBE4DB9E55558" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_RestructuringProgramsLayoffsTwoThousandSeventeenMember_EAE5C0BD66E8E231CAAFBE4DB9E55558" xlink:to="lab_arnc_RestructuringProgramsLayoffsTwoThousandSeventeenMember_EAE5C0BD66E8E231CAAFBE4DB9E55558" xlink:type="arc" />
    <link:label id="lab_arnc_RestructuringAndOtherChargesAfterTax_EFFE488D67756E948FBCBE4DB9E52566_terseLabel_en-US" xlink:label="lab_arnc_RestructuringAndOtherChargesAfterTax_EFFE488D67756E948FBCBE4DB9E52566" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Restructuring and other charges after tax</link:label>
    <link:label id="lab_arnc_RestructuringAndOtherChargesAfterTax_EFFE488D67756E948FBCBE4DB9E52566_label_en-US" xlink:label="lab_arnc_RestructuringAndOtherChargesAfterTax_EFFE488D67756E948FBCBE4DB9E52566" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Restructuring And Other Charges After Tax</link:label>
    <link:label id="lab_arnc_RestructuringAndOtherChargesAfterTax_EFFE488D67756E948FBCBE4DB9E52566_documentation_en-US" xlink:label="lab_arnc_RestructuringAndOtherChargesAfterTax_EFFE488D67756E948FBCBE4DB9E52566" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Restructuring and other charges after tax.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_RestructuringAndOtherChargesAfterTax" xlink:label="loc_arnc_RestructuringAndOtherChargesAfterTax_EFFE488D67756E948FBCBE4DB9E52566" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_RestructuringAndOtherChargesAfterTax_EFFE488D67756E948FBCBE4DB9E52566" xlink:to="lab_arnc_RestructuringAndOtherChargesAfterTax_EFFE488D67756E948FBCBE4DB9E52566" xlink:type="arc" />
    <link:label id="lab_us-gaap_RestructuringAndRelatedCostNumberOfPositionsEliminated_CE2778E95311868409C6BE4DB9E61EAE_terseLabel_en-US" xlink:label="lab_us-gaap_RestructuringAndRelatedCostNumberOfPositionsEliminated_CE2778E95311868409C6BE4DB9E61EAE" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Number of employees associated with layoff costs</link:label>
    <link:label id="lab_us-gaap_RestructuringAndRelatedCostNumberOfPositionsEliminated_CE2778E95311868409C6BE4DB9E61EAE_label_en-US" xlink:label="lab_us-gaap_RestructuringAndRelatedCostNumberOfPositionsEliminated_CE2778E95311868409C6BE4DB9E61EAE" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Restructuring and Related Cost, Number of Positions Eliminated</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RestructuringAndRelatedCostNumberOfPositionsEliminated" xlink:label="loc_us-gaap_RestructuringAndRelatedCostNumberOfPositionsEliminated_CE2778E95311868409C6BE4DB9E61EAE" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RestructuringAndRelatedCostNumberOfPositionsEliminated_CE2778E95311868409C6BE4DB9E61EAE" xlink:to="lab_us-gaap_RestructuringAndRelatedCostNumberOfPositionsEliminated_CE2778E95311868409C6BE4DB9E61EAE" xlink:type="arc" />
    <link:label id="lab_arnc_RestructuringAndOtherChargesAfterTaxAndNoncontrollingInterests_DD47FEC8A73850558C2FBE4DB9E6A47E_terseLabel_en-US" xlink:label="lab_arnc_RestructuringAndOtherChargesAfterTaxAndNoncontrollingInterests_DD47FEC8A73850558C2FBE4DB9E6A47E" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Restructuring and other charges after tax and noncontrolling interests</link:label>
    <link:label id="lab_arnc_RestructuringAndOtherChargesAfterTaxAndNoncontrollingInterests_DD47FEC8A73850558C2FBE4DB9E6A47E_label_en-US" xlink:label="lab_arnc_RestructuringAndOtherChargesAfterTaxAndNoncontrollingInterests_DD47FEC8A73850558C2FBE4DB9E6A47E" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Restructuring And Other Charges After Tax And Noncontrolling Interests</link:label>
    <link:label id="lab_arnc_RestructuringAndOtherChargesAfterTaxAndNoncontrollingInterests_DD47FEC8A73850558C2FBE4DB9E6A47E_documentation_en-US" xlink:label="lab_arnc_RestructuringAndOtherChargesAfterTaxAndNoncontrollingInterests_DD47FEC8A73850558C2FBE4DB9E6A47E" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Amount charged against earnings in the period after-tax and noncontrolling interests for incurred and estimated costs associated with exit from or disposal of business activities or restructurings pursuant to a program that is planned and controlled by management, and materially changes either the scope of a business undertaken by an entity, or the manner in which that business is conducted.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_RestructuringAndOtherChargesAfterTaxAndNoncontrollingInterests" xlink:label="loc_arnc_RestructuringAndOtherChargesAfterTaxAndNoncontrollingInterests_DD47FEC8A73850558C2FBE4DB9E6A47E" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_RestructuringAndOtherChargesAfterTaxAndNoncontrollingInterests_DD47FEC8A73850558C2FBE4DB9E6A47E" xlink:to="lab_arnc_RestructuringAndOtherChargesAfterTaxAndNoncontrollingInterests_DD47FEC8A73850558C2FBE4DB9E6A47E" xlink:type="arc" />
    <link:label id="lab_arnc_ReversalOfForfeitedExecutiveStockCompensation_B6D10909483E043D5890BE4DB9E68642_terseLabel_en-US" xlink:label="lab_arnc_ReversalOfForfeitedExecutiveStockCompensation_B6D10909483E043D5890BE4DB9E68642" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Reversal of forfeited executive stock compensation</link:label>
    <link:label id="lab_arnc_ReversalOfForfeitedExecutiveStockCompensation_B6D10909483E043D5890BE4DB9E68642_label_en-US" xlink:label="lab_arnc_ReversalOfForfeitedExecutiveStockCompensation_B6D10909483E043D5890BE4DB9E68642" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Reversal Of Forfeited Executive Stock Compensation</link:label>
    <link:label id="lab_arnc_ReversalOfForfeitedExecutiveStockCompensation_B6D10909483E043D5890BE4DB9E68642_documentation_en-US" xlink:label="lab_arnc_ReversalOfForfeitedExecutiveStockCompensation_B6D10909483E043D5890BE4DB9E68642" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Reversal of forfeited executive stock compensation.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_ReversalOfForfeitedExecutiveStockCompensation" xlink:label="loc_arnc_ReversalOfForfeitedExecutiveStockCompensation_B6D10909483E043D5890BE4DB9E68642" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_ReversalOfForfeitedExecutiveStockCompensation_B6D10909483E043D5890BE4DB9E68642" xlink:to="lab_arnc_ReversalOfForfeitedExecutiveStockCompensation_B6D10909483E043D5890BE4DB9E68642" xlink:type="arc" />
    <link:label id="lab_us-gaap_SeveranceCosts1_0BFB5FF691AE6EB449BDBE4DB9E66574_verboseLabel_en-US" xlink:label="lab_us-gaap_SeveranceCosts1_0BFB5FF691AE6EB449BDBE4DB9E66574" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Severance costs</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_SeveranceCosts1" xlink:label="loc_us-gaap_SeveranceCosts1_0BFB5FF691AE6EB449BDBE4DB9E66574" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SeveranceCosts1_0BFB5FF691AE6EB449BDBE4DB9E66574" xlink:to="lab_us-gaap_SeveranceCosts1_0BFB5FF691AE6EB449BDBE4DB9E66574" xlink:type="arc" />
    <link:label id="lab_us-gaap_RestructuringAndRelatedCostNumberOfPositionsEliminatedInceptionToDate_3E752C09DF6866BB6C02BE4DB9E662DF_terseLabel_en-US" xlink:label="lab_us-gaap_RestructuringAndRelatedCostNumberOfPositionsEliminatedInceptionToDate_3E752C09DF6866BB6C02BE4DB9E662DF" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Approximate number of employees already laid off</link:label>
    <link:label id="lab_us-gaap_RestructuringAndRelatedCostNumberOfPositionsEliminatedInceptionToDate_3E752C09DF6866BB6C02BE4DB9E662DF_label_en-US" xlink:label="lab_us-gaap_RestructuringAndRelatedCostNumberOfPositionsEliminatedInceptionToDate_3E752C09DF6866BB6C02BE4DB9E662DF" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Restructuring and Related Cost, Number of Positions Eliminated, Inception to Date</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RestructuringAndRelatedCostNumberOfPositionsEliminatedInceptionToDate" xlink:label="loc_us-gaap_RestructuringAndRelatedCostNumberOfPositionsEliminatedInceptionToDate_3E752C09DF6866BB6C02BE4DB9E662DF" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RestructuringAndRelatedCostNumberOfPositionsEliminatedInceptionToDate_3E752C09DF6866BB6C02BE4DB9E662DF" xlink:to="lab_us-gaap_RestructuringAndRelatedCostNumberOfPositionsEliminatedInceptionToDate_3E752C09DF6866BB6C02BE4DB9E662DF" xlink:type="arc" />
    <link:label id="lab_us-gaap_PaymentsForRestructuring_481499AE8F2E46B79CCABE4DB9E66D84_terseLabel_en-US" xlink:label="lab_us-gaap_PaymentsForRestructuring_481499AE8F2E46B79CCABE4DB9E66D84" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Cash payments for restructuring</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PaymentsForRestructuring" xlink:label="loc_us-gaap_PaymentsForRestructuring_481499AE8F2E46B79CCABE4DB9E66D84" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PaymentsForRestructuring_481499AE8F2E46B79CCABE4DB9E66D84" xlink:to="lab_us-gaap_PaymentsForRestructuring_481499AE8F2E46B79CCABE4DB9E66D84" xlink:type="arc" />
    <link:label id="lab_arnc_RestructuringChargeForLayoffs_F064CC7F587C19AC3DC5BE4DB9E72842_verboseLabel_en-US" xlink:label="lab_arnc_RestructuringChargeForLayoffs_F064CC7F587C19AC3DC5BE4DB9E72842" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Restructuring charges for layoffs</link:label>
    <link:label id="lab_arnc_RestructuringChargeForLayoffs_F064CC7F587C19AC3DC5BE4DB9E72842_label_en-US" xlink:label="lab_arnc_RestructuringChargeForLayoffs_F064CC7F587C19AC3DC5BE4DB9E72842" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Restructuring Charge For Layoffs</link:label>
    <link:label id="lab_arnc_RestructuringChargeForLayoffs_F064CC7F587C19AC3DC5BE4DB9E72842_documentation_en-US" xlink:label="lab_arnc_RestructuringChargeForLayoffs_F064CC7F587C19AC3DC5BE4DB9E72842" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Restructuring charge for layoffs.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_RestructuringChargeForLayoffs" xlink:label="loc_arnc_RestructuringChargeForLayoffs_F064CC7F587C19AC3DC5BE4DB9E72842" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_RestructuringChargeForLayoffs_F064CC7F587C19AC3DC5BE4DB9E72842" xlink:to="lab_arnc_RestructuringChargeForLayoffs_F064CC7F587C19AC3DC5BE4DB9E72842" xlink:type="arc" />
    <link:label id="lab_arnc_NewYorkofficeMember_5815DFA4BB71ED7AC86CC968C22638B4_terseLabel_en-US" xlink:label="lab_arnc_NewYorkofficeMember_5815DFA4BB71ED7AC86CC968C22638B4" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">New York office</link:label>
    <link:label id="lab_arnc_NewYorkofficeMember_5815DFA4BB71ED7AC86CC968C22638B4_label_en-US" xlink:label="lab_arnc_NewYorkofficeMember_5815DFA4BB71ED7AC86CC968C22638B4" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">New York office [Member]</link:label>
    <link:label id="lab_arnc_NewYorkofficeMember_5815DFA4BB71ED7AC86CC968C22638B4_documentation_en-US" xlink:label="lab_arnc_NewYorkofficeMember_5815DFA4BB71ED7AC86CC968C22638B4" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">New York office [Member]</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_NewYorkofficeMember" xlink:label="loc_arnc_NewYorkofficeMember_5815DFA4BB71ED7AC86CC968C22638B4" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_NewYorkofficeMember_5815DFA4BB71ED7AC86CC968C22638B4" xlink:to="lab_arnc_NewYorkofficeMember_5815DFA4BB71ED7AC86CC968C22638B4" xlink:type="arc" />
    <link:label id="lab_arnc_PensionCurtailmentChargeMember_DD78404B0DADF6050643C968C22726EE_terseLabel_en-US" xlink:label="lab_arnc_PensionCurtailmentChargeMember_DD78404B0DADF6050643C968C22726EE" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Pension Curtailment Charge</link:label>
    <link:label id="lab_arnc_PensionCurtailmentChargeMember_DD78404B0DADF6050643C968C22726EE_label_en-US" xlink:label="lab_arnc_PensionCurtailmentChargeMember_DD78404B0DADF6050643C968C22726EE" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Pension Curtailment Charge [Member]</link:label>
    <link:label id="lab_arnc_PensionCurtailmentChargeMember_DD78404B0DADF6050643C968C22726EE_documentation_en-US" xlink:label="lab_arnc_PensionCurtailmentChargeMember_DD78404B0DADF6050643C968C22726EE" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Pension Curtailment Charge [Member]</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_PensionCurtailmentChargeMember" xlink:label="loc_arnc_PensionCurtailmentChargeMember_DD78404B0DADF6050643C968C22726EE" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_PensionCurtailmentChargeMember_DD78404B0DADF6050643C968C22726EE" xlink:to="lab_arnc_PensionCurtailmentChargeMember_DD78404B0DADF6050643C968C22726EE" xlink:type="arc" />
    <link:label id="lab_arnc_PostretirementCurtailmentBenefitMember_5FEC10C70A29C0E5034BC968C22774C9_terseLabel_en-US" xlink:label="lab_arnc_PostretirementCurtailmentBenefitMember_5FEC10C70A29C0E5034BC968C22774C9" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Postretirement Curtailment Benefit</link:label>
    <link:label id="lab_arnc_PostretirementCurtailmentBenefitMember_5FEC10C70A29C0E5034BC968C22774C9_label_en-US" xlink:label="lab_arnc_PostretirementCurtailmentBenefitMember_5FEC10C70A29C0E5034BC968C22774C9" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Postretirement Curtailment Benefit [Member]</link:label>
    <link:label id="lab_arnc_PostretirementCurtailmentBenefitMember_5FEC10C70A29C0E5034BC968C22774C9_documentation_en-US" xlink:label="lab_arnc_PostretirementCurtailmentBenefitMember_5FEC10C70A29C0E5034BC968C22774C9" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Postretirement Curtailment Benefit [Member]</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_PostretirementCurtailmentBenefitMember" xlink:label="loc_arnc_PostretirementCurtailmentBenefitMember_5FEC10C70A29C0E5034BC968C22774C9" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_PostretirementCurtailmentBenefitMember_5FEC10C70A29C0E5034BC968C22774C9" xlink:to="lab_arnc_PostretirementCurtailmentBenefitMember_5FEC10C70A29C0E5034BC968C22774C9" xlink:type="arc" />
    <link:label id="lab_arnc_RestructuringProgramsLayoffsMember_80454790C9A3D950622EC968C2281129_terseLabel_en-US" xlink:label="lab_arnc_RestructuringProgramsLayoffsMember_80454790C9A3D950622EC968C2281129" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Restructuring Programs Layoffs</link:label>
    <link:label id="lab_arnc_RestructuringProgramsLayoffsMember_80454790C9A3D950622EC968C2281129_label_en-US" xlink:label="lab_arnc_RestructuringProgramsLayoffsMember_80454790C9A3D950622EC968C2281129" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Restructuring Programs Layoffs [Member]</link:label>
    <link:label id="lab_arnc_RestructuringProgramsLayoffsMember_80454790C9A3D950622EC968C2281129_documentation_en-US" xlink:label="lab_arnc_RestructuringProgramsLayoffsMember_80454790C9A3D950622EC968C2281129" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Restructuring programs layoffs.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_RestructuringProgramsLayoffsMember" xlink:label="loc_arnc_RestructuringProgramsLayoffsMember_80454790C9A3D950622EC968C2281129" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_RestructuringProgramsLayoffsMember_80454790C9A3D950622EC968C2281129" xlink:to="lab_arnc_RestructuringProgramsLayoffsMember_80454790C9A3D950622EC968C2281129" xlink:type="arc" />
    <link:label id="lab_arnc_RestructuringProgramsLayoffsTwoThousandEighteenMember_A22D9BEF6DDA3FB161C3C968C228D31A_terseLabel_en-US" xlink:label="lab_arnc_RestructuringProgramsLayoffsTwoThousandEighteenMember_A22D9BEF6DDA3FB161C3C968C228D31A" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Restructuring Programs Layoffs Two Thousand Eighteen</link:label>
    <link:label id="lab_arnc_RestructuringProgramsLayoffsTwoThousandEighteenMember_A22D9BEF6DDA3FB161C3C968C228D31A_label_en-US" xlink:label="lab_arnc_RestructuringProgramsLayoffsTwoThousandEighteenMember_A22D9BEF6DDA3FB161C3C968C228D31A" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Restructuring Programs Layoffs Two Thousand Eighteen [Member]</link:label>
    <link:label id="lab_arnc_RestructuringProgramsLayoffsTwoThousandEighteenMember_A22D9BEF6DDA3FB161C3C968C228D31A_documentation_en-US" xlink:label="lab_arnc_RestructuringProgramsLayoffsTwoThousandEighteenMember_A22D9BEF6DDA3FB161C3C968C228D31A" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Restructuring Programs Layoffs Two Thousand Eighteen [Member]</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_RestructuringProgramsLayoffsTwoThousandEighteenMember" xlink:label="loc_arnc_RestructuringProgramsLayoffsTwoThousandEighteenMember_A22D9BEF6DDA3FB161C3C968C228D31A" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_RestructuringProgramsLayoffsTwoThousandEighteenMember_A22D9BEF6DDA3FB161C3C968C228D31A" xlink:to="lab_arnc_RestructuringProgramsLayoffsTwoThousandEighteenMember_A22D9BEF6DDA3FB161C3C968C228D31A" xlink:type="arc" />
    <link:label id="lab_us-gaap_FacilityClosingMember_3E77120ACD6DF872BDD1C968C228D954_terseLabel_en-US" xlink:label="lab_us-gaap_FacilityClosingMember_3E77120ACD6DF872BDD1C968C228D954" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Facility Closing</link:label>
    <link:label id="lab_us-gaap_FacilityClosingMember_3E77120ACD6DF872BDD1C968C228D954_label_en-US" xlink:label="lab_us-gaap_FacilityClosingMember_3E77120ACD6DF872BDD1C968C228D954" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Facility Closing [Member]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_FacilityClosingMember" xlink:label="loc_us-gaap_FacilityClosingMember_3E77120ACD6DF872BDD1C968C228D954" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FacilityClosingMember_3E77120ACD6DF872BDD1C968C228D954" xlink:to="lab_us-gaap_FacilityClosingMember_3E77120ACD6DF872BDD1C968C228D954" xlink:type="arc" />
    <link:label id="lab_us-gaap_GainLossOnSaleOfBusiness_067EE8BD6F03F155A168C968C230219A_verboseLabel_en-US" xlink:label="lab_us-gaap_GainLossOnSaleOfBusiness_067EE8BD6F03F155A168C968C230219A" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Gain (loss) on disposition of business, before tax</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_GainLossOnSaleOfBusiness" xlink:label="loc_us-gaap_GainLossOnSaleOfBusiness_067EE8BD6F03F155A168C968C230219A" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_GainLossOnSaleOfBusiness_067EE8BD6F03F155A168C968C230219A" xlink:to="lab_us-gaap_GainLossOnSaleOfBusiness_067EE8BD6F03F155A168C968C230219A" xlink:type="arc" />
    <link:label id="lab_us-gaap_GainLossOnDispositionOfAssets1_8B39929706002E2229ABC968C2309E3A_verboseLabel_en-US" xlink:label="lab_us-gaap_GainLossOnDispositionOfAssets1_8B39929706002E2229ABC968C2309E3A" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Gain (loss) on disposition of assets, before tax</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_GainLossOnDispositionOfAssets1" xlink:label="loc_us-gaap_GainLossOnDispositionOfAssets1_8B39929706002E2229ABC968C2309E3A" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_GainLossOnDispositionOfAssets1_8B39929706002E2229ABC968C2309E3A" xlink:to="lab_us-gaap_GainLossOnDispositionOfAssets1_8B39929706002E2229ABC968C2309E3A" xlink:type="arc" />
    <link:label id="lab_us-gaap_AccountsPayableAccruedLiabilitiesAndOtherLiabilitiesDisclosureNoncurrentTextBlock_83AAF21ACCDDB5151C65E244A966C93E_terseLabel_en-US" xlink:label="lab_us-gaap_AccountsPayableAccruedLiabilitiesAndOtherLiabilitiesDisclosureNoncurrentTextBlock_83AAF21ACCDDB5151C65E244A966C93E" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Other Noncurrent Liabilities and Deferred Credits</link:label>
    <link:label id="lab_us-gaap_AccountsPayableAccruedLiabilitiesAndOtherLiabilitiesDisclosureNoncurrentTextBlock_83AAF21ACCDDB5151C65E244A966C93E_label_en-US" xlink:label="lab_us-gaap_AccountsPayableAccruedLiabilitiesAndOtherLiabilitiesDisclosureNoncurrentTextBlock_83AAF21ACCDDB5151C65E244A966C93E" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Accounts Payable, Accrued Liabilities, and Other Liabilities Disclosure, Noncurrent [Text Block]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AccountsPayableAccruedLiabilitiesAndOtherLiabilitiesDisclosureNoncurrentTextBlock" xlink:label="loc_us-gaap_AccountsPayableAccruedLiabilitiesAndOtherLiabilitiesDisclosureNoncurrentTextBlock_83AAF21ACCDDB5151C65E244A966C93E" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AccountsPayableAccruedLiabilitiesAndOtherLiabilitiesDisclosureNoncurrentTextBlock_83AAF21ACCDDB5151C65E244A966C93E" xlink:to="lab_us-gaap_AccountsPayableAccruedLiabilitiesAndOtherLiabilitiesDisclosureNoncurrentTextBlock_83AAF21ACCDDB5151C65E244A966C93E" xlink:type="arc" />
    <link:label id="lab_us-gaap_AccruedEnvironmentalLossContingenciesNoncurrent_2A5549AF5E2DE9C5F10EEDFC569A0690_terseLabel_en-US" xlink:label="lab_us-gaap_AccruedEnvironmentalLossContingenciesNoncurrent_2A5549AF5E2DE9C5F10EEDFC569A0690" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Environmental remediation (U)</link:label>
    <link:label id="lab_us-gaap_AccruedEnvironmentalLossContingenciesNoncurrent_2A5549AF5E2DE9C5F10EEDFC569A0690_label_en-US" xlink:label="lab_us-gaap_AccruedEnvironmentalLossContingenciesNoncurrent_2A5549AF5E2DE9C5F10EEDFC569A0690" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Accrued Environmental Loss Contingencies, Noncurrent</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AccruedEnvironmentalLossContingenciesNoncurrent" xlink:label="loc_us-gaap_AccruedEnvironmentalLossContingenciesNoncurrent_2A5549AF5E2DE9C5F10EEDFC569A0690" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AccruedEnvironmentalLossContingenciesNoncurrent_2A5549AF5E2DE9C5F10EEDFC569A0690" xlink:to="lab_us-gaap_AccruedEnvironmentalLossContingenciesNoncurrent_2A5549AF5E2DE9C5F10EEDFC569A0690" xlink:type="arc" />
    <link:label id="lab_us-gaap_AccruedIncomeTaxesNoncurrent_15C924F71BB0755240D4EDFC569BE231_terseLabel_en-US" xlink:label="lab_us-gaap_AccruedIncomeTaxesNoncurrent_15C924F71BB0755240D4EDFC569BE231" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Income taxes (H)</link:label>
    <link:label id="lab_us-gaap_AccruedIncomeTaxesNoncurrent_15C924F71BB0755240D4EDFC569BE231_label_en-US" xlink:label="lab_us-gaap_AccruedIncomeTaxesNoncurrent_15C924F71BB0755240D4EDFC569BE231" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Accrued Income Taxes, Noncurrent</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AccruedIncomeTaxesNoncurrent" xlink:label="loc_us-gaap_AccruedIncomeTaxesNoncurrent_15C924F71BB0755240D4EDFC569BE231" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AccruedIncomeTaxesNoncurrent_15C924F71BB0755240D4EDFC569BE231" xlink:to="lab_us-gaap_AccruedIncomeTaxesNoncurrent_15C924F71BB0755240D4EDFC569BE231" xlink:type="arc" />
    <link:label id="lab_us-gaap_DeferredCompensationLiabilityClassifiedNoncurrent_995758D25CAA1F6953A4EDFC569BFD90_terseLabel_en-US" xlink:label="lab_us-gaap_DeferredCompensationLiabilityClassifiedNoncurrent_995758D25CAA1F6953A4EDFC569BFD90" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Accrued compensation and retirement costs</link:label>
    <link:label id="lab_us-gaap_DeferredCompensationLiabilityClassifiedNoncurrent_995758D25CAA1F6953A4EDFC569BFD90_label_en-US" xlink:label="lab_us-gaap_DeferredCompensationLiabilityClassifiedNoncurrent_995758D25CAA1F6953A4EDFC569BFD90" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Deferred Compensation Liability, Classified, Noncurrent</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DeferredCompensationLiabilityClassifiedNoncurrent" xlink:label="loc_us-gaap_DeferredCompensationLiabilityClassifiedNoncurrent_995758D25CAA1F6953A4EDFC569BFD90" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DeferredCompensationLiabilityClassifiedNoncurrent_995758D25CAA1F6953A4EDFC569BFD90" xlink:to="lab_us-gaap_DeferredCompensationLiabilityClassifiedNoncurrent_995758D25CAA1F6953A4EDFC569BFD90" xlink:type="arc" />
    <link:label id="lab_us-gaap_SaleLeasebackTransactionAmountDueUnderFinancingArrangement_F56649A23460F63E1146EDFC569BFB50_terseLabel_en-US" xlink:label="lab_us-gaap_SaleLeasebackTransactionAmountDueUnderFinancingArrangement_F56649A23460F63E1146EDFC569BFB50" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Sale-leaseback financing obligation</link:label>
    <link:label id="lab_us-gaap_SaleLeasebackTransactionAmountDueUnderFinancingArrangement_F56649A23460F63E1146EDFC569BFB50_label_en-US" xlink:label="lab_us-gaap_SaleLeasebackTransactionAmountDueUnderFinancingArrangement_F56649A23460F63E1146EDFC569BFB50" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Sale Leaseback Transaction, Amount Due under Financing Arrangement</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_SaleLeasebackTransactionAmountDueUnderFinancingArrangement" xlink:label="loc_us-gaap_SaleLeasebackTransactionAmountDueUnderFinancingArrangement_F56649A23460F63E1146EDFC569BFB50" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SaleLeasebackTransactionAmountDueUnderFinancingArrangement_F56649A23460F63E1146EDFC569BFB50" xlink:to="lab_us-gaap_SaleLeasebackTransactionAmountDueUnderFinancingArrangement_F56649A23460F63E1146EDFC569BFB50" xlink:type="arc" />
    <link:label id="lab_us-gaap_OtherSundryLiabilitiesNoncurrent_7AADD680E1873BFABF06EDFC569BE007_terseLabel_en-US" xlink:label="lab_us-gaap_OtherSundryLiabilitiesNoncurrent_7AADD680E1873BFABF06EDFC569BE007" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Other</link:label>
    <link:label id="lab_us-gaap_OtherSundryLiabilitiesNoncurrent_7AADD680E1873BFABF06EDFC569BE007_label_en-US" xlink:label="lab_us-gaap_OtherSundryLiabilitiesNoncurrent_7AADD680E1873BFABF06EDFC569BE007" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Other Sundry Liabilities, Noncurrent</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_OtherSundryLiabilitiesNoncurrent" xlink:label="loc_us-gaap_OtherSundryLiabilitiesNoncurrent_7AADD680E1873BFABF06EDFC569BE007" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OtherSundryLiabilitiesNoncurrent_7AADD680E1873BFABF06EDFC569BE007" xlink:to="lab_us-gaap_OtherSundryLiabilitiesNoncurrent_7AADD680E1873BFABF06EDFC569BE007" xlink:type="arc" />
    <link:label id="lab_us-gaap_DeferredCreditsAndOtherLiabilitiesNoncurrent_D6C6D9651578C4CA9E97EDFC569C7A30_totalLabel_en-US" xlink:label="lab_us-gaap_DeferredCreditsAndOtherLiabilitiesNoncurrent_D6C6D9651578C4CA9E97EDFC569C7A30" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Other noncurrent liabilities and deferred credits</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DeferredCreditsAndOtherLiabilitiesNoncurrent" xlink:label="loc_us-gaap_DeferredCreditsAndOtherLiabilitiesNoncurrent_D6C6D9651578C4CA9E97EDFC569C7A30" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DeferredCreditsAndOtherLiabilitiesNoncurrent_D6C6D9651578C4CA9E97EDFC569C7A30" xlink:to="lab_us-gaap_DeferredCreditsAndOtherLiabilitiesNoncurrent_D6C6D9651578C4CA9E97EDFC569C7A30" xlink:type="arc" />
    <link:label id="lab_us-gaap_TaxCreditCarryforwardTable_15D24A467C952D01D23B06E20D0F8197_terseLabel_en-US" xlink:label="lab_us-gaap_TaxCreditCarryforwardTable_15D24A467C952D01D23B06E20D0F8197" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Tax Credit Carryforward [Table]</link:label>
    <link:label id="lab_us-gaap_TaxCreditCarryforwardTable_15D24A467C952D01D23B06E20D0F8197_label_en-US" xlink:label="lab_us-gaap_TaxCreditCarryforwardTable_15D24A467C952D01D23B06E20D0F8197" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Tax Credit Carryforward [Table]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_TaxCreditCarryforwardTable" xlink:label="loc_us-gaap_TaxCreditCarryforwardTable_15D24A467C952D01D23B06E20D0F8197" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_TaxCreditCarryforwardTable_15D24A467C952D01D23B06E20D0F8197" xlink:to="lab_us-gaap_TaxCreditCarryforwardTable_15D24A467C952D01D23B06E20D0F8197" xlink:type="arc" />
    <link:label id="lab_us-gaap_ValuationAllowancesAndReservesTypeAxis_56193C04BA78FF49081006E20D0FBD23_terseLabel_en-US" xlink:label="lab_us-gaap_ValuationAllowancesAndReservesTypeAxis_56193C04BA78FF49081006E20D0FBD23" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">SEC Schedule, 12-09, Valuation Allowances and Reserves Type [Axis]</link:label>
    <link:label id="lab_us-gaap_ValuationAllowancesAndReservesTypeAxis_56193C04BA78FF49081006E20D0FBD23_label_en-US" xlink:label="lab_us-gaap_ValuationAllowancesAndReservesTypeAxis_56193C04BA78FF49081006E20D0FBD23" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">SEC Schedule, 12-09, Valuation Allowances and Reserves Type [Axis]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ValuationAllowancesAndReservesTypeAxis" xlink:label="loc_us-gaap_ValuationAllowancesAndReservesTypeAxis_56193C04BA78FF49081006E20D0FBD23" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ValuationAllowancesAndReservesTypeAxis_56193C04BA78FF49081006E20D0FBD23" xlink:to="lab_us-gaap_ValuationAllowancesAndReservesTypeAxis_56193C04BA78FF49081006E20D0FBD23" xlink:type="arc" />
    <link:label id="lab_us-gaap_ValuationAllowancesAndReservesDomain_24869CDF8B585FCEFF4106E20D0FF259_terseLabel_en-US" xlink:label="lab_us-gaap_ValuationAllowancesAndReservesDomain_24869CDF8B585FCEFF4106E20D0FF259" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">SEC Schedule, 12-09, Valuation Allowances and Reserves [Domain]</link:label>
    <link:label id="lab_us-gaap_ValuationAllowancesAndReservesDomain_24869CDF8B585FCEFF4106E20D0FF259_label_en-US" xlink:label="lab_us-gaap_ValuationAllowancesAndReservesDomain_24869CDF8B585FCEFF4106E20D0FF259" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">SEC Schedule, 12-09, Valuation Allowances and Reserves [Domain]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ValuationAllowancesAndReservesDomain" xlink:label="loc_us-gaap_ValuationAllowancesAndReservesDomain_24869CDF8B585FCEFF4106E20D0FF259" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ValuationAllowancesAndReservesDomain_24869CDF8B585FCEFF4106E20D0FF259" xlink:to="lab_us-gaap_ValuationAllowancesAndReservesDomain_24869CDF8B585FCEFF4106E20D0FF259" xlink:type="arc" />
    <link:label id="lab_arnc_ExpiresWithinTenYearsMember_C980ACCD7DEF14BCA81A06E20D10EB1B_terseLabel_en-US" xlink:label="lab_arnc_ExpiresWithinTenYearsMember_C980ACCD7DEF14BCA81A06E20D10EB1B" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Expires within 10 years</link:label>
    <link:label id="lab_arnc_ExpiresWithinTenYearsMember_C980ACCD7DEF14BCA81A06E20D10EB1B_label_en-US" xlink:label="lab_arnc_ExpiresWithinTenYearsMember_C980ACCD7DEF14BCA81A06E20D10EB1B" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Expires Within Ten Years [Member]</link:label>
    <link:label id="lab_arnc_ExpiresWithinTenYearsMember_C980ACCD7DEF14BCA81A06E20D10EB1B_documentation_en-US" xlink:label="lab_arnc_ExpiresWithinTenYearsMember_C980ACCD7DEF14BCA81A06E20D10EB1B" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Expires Within Ten Years [Member]</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_ExpiresWithinTenYearsMember" xlink:label="loc_arnc_ExpiresWithinTenYearsMember_C980ACCD7DEF14BCA81A06E20D10EB1B" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_ExpiresWithinTenYearsMember_C980ACCD7DEF14BCA81A06E20D10EB1B" xlink:to="lab_arnc_ExpiresWithinTenYearsMember_C980ACCD7DEF14BCA81A06E20D10EB1B" xlink:type="arc" />
    <link:label id="lab_arnc_ExpiresWithinElevenToTwentyYearsMember_626BAC953A6E93C6156F06E20D1068B5_terseLabel_en-US" xlink:label="lab_arnc_ExpiresWithinElevenToTwentyYearsMember_626BAC953A6E93C6156F06E20D1068B5" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Expires within 11-20 years</link:label>
    <link:label id="lab_arnc_ExpiresWithinElevenToTwentyYearsMember_626BAC953A6E93C6156F06E20D1068B5_label_en-US" xlink:label="lab_arnc_ExpiresWithinElevenToTwentyYearsMember_626BAC953A6E93C6156F06E20D1068B5" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Expires Within Eleven To Twenty Years [Member]</link:label>
    <link:label id="lab_arnc_ExpiresWithinElevenToTwentyYearsMember_626BAC953A6E93C6156F06E20D1068B5_documentation_en-US" xlink:label="lab_arnc_ExpiresWithinElevenToTwentyYearsMember_626BAC953A6E93C6156F06E20D1068B5" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Expires Within Eleven To Twenty Years [Member]</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_ExpiresWithinElevenToTwentyYearsMember" xlink:label="loc_arnc_ExpiresWithinElevenToTwentyYearsMember_626BAC953A6E93C6156F06E20D1068B5" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_ExpiresWithinElevenToTwentyYearsMember_626BAC953A6E93C6156F06E20D1068B5" xlink:to="lab_arnc_ExpiresWithinElevenToTwentyYearsMember_626BAC953A6E93C6156F06E20D1068B5" xlink:type="arc" />
    <link:label id="lab_arnc_NoExpirationMember_7AABA259F3B4A7D728F006E20D10E328_terseLabel_en-US" xlink:label="lab_arnc_NoExpirationMember_7AABA259F3B4A7D728F006E20D10E328" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">No expiration</link:label>
    <link:label id="lab_arnc_NoExpirationMember_7AABA259F3B4A7D728F006E20D10E328_label_en-US" xlink:label="lab_arnc_NoExpirationMember_7AABA259F3B4A7D728F006E20D10E328" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">No Expiration [Member]</link:label>
    <link:label id="lab_arnc_NoExpirationMember_7AABA259F3B4A7D728F006E20D10E328_documentation_en-US" xlink:label="lab_arnc_NoExpirationMember_7AABA259F3B4A7D728F006E20D10E328" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">No Expiration [Member]</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_NoExpirationMember" xlink:label="loc_arnc_NoExpirationMember_7AABA259F3B4A7D728F006E20D10E328" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_NoExpirationMember_7AABA259F3B4A7D728F006E20D10E328" xlink:to="lab_arnc_NoExpirationMember_7AABA259F3B4A7D728F006E20D10E328" xlink:type="arc" />
    <link:label id="lab_arnc_OtherDeferredTaxAssetsMember_4D18B2D370581B6785CA06E20D102224_terseLabel_en-US" xlink:label="lab_arnc_OtherDeferredTaxAssetsMember_4D18B2D370581B6785CA06E20D102224" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Other(2)</link:label>
    <link:label id="lab_arnc_OtherDeferredTaxAssetsMember_4D18B2D370581B6785CA06E20D102224_label_en-US" xlink:label="lab_arnc_OtherDeferredTaxAssetsMember_4D18B2D370581B6785CA06E20D102224" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Other Deferred Tax Assets [Member]</link:label>
    <link:label id="lab_arnc_OtherDeferredTaxAssetsMember_4D18B2D370581B6785CA06E20D102224_documentation_en-US" xlink:label="lab_arnc_OtherDeferredTaxAssetsMember_4D18B2D370581B6785CA06E20D102224" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Other Deferred Tax Assets [Member]</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_OtherDeferredTaxAssetsMember" xlink:label="loc_arnc_OtherDeferredTaxAssetsMember_4D18B2D370581B6785CA06E20D102224" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_OtherDeferredTaxAssetsMember_4D18B2D370581B6785CA06E20D102224" xlink:to="lab_arnc_OtherDeferredTaxAssetsMember_4D18B2D370581B6785CA06E20D102224" xlink:type="arc" />
    <link:label id="lab_us-gaap_TaxCreditCarryforwardLineItems_CD1B6EC7803490E66A5006E20D118262_terseLabel_en-US" xlink:label="lab_us-gaap_TaxCreditCarryforwardLineItems_CD1B6EC7803490E66A5006E20D118262" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Tax Credit Carryforward [Line Items]</link:label>
    <link:label id="lab_us-gaap_TaxCreditCarryforwardLineItems_CD1B6EC7803490E66A5006E20D118262_label_en-US" xlink:label="lab_us-gaap_TaxCreditCarryforwardLineItems_CD1B6EC7803490E66A5006E20D118262" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Tax Credit Carryforward [Line Items]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_TaxCreditCarryforwardLineItems" xlink:label="loc_us-gaap_TaxCreditCarryforwardLineItems_CD1B6EC7803490E66A5006E20D118262" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_TaxCreditCarryforwardLineItems_CD1B6EC7803490E66A5006E20D118262" xlink:to="lab_us-gaap_TaxCreditCarryforwardLineItems_CD1B6EC7803490E66A5006E20D118262" xlink:type="arc" />
    <link:label id="lab_us-gaap_OperatingLossCarryforwards_04EE536D0C523141263206E20D1135AD_terseLabel_en-US" xlink:label="lab_us-gaap_OperatingLossCarryforwards_04EE536D0C523141263206E20D1135AD" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Tax loss carryforwards</link:label>
    <link:label id="lab_us-gaap_OperatingLossCarryforwards_04EE536D0C523141263206E20D1135AD_label_en-US" xlink:label="lab_us-gaap_OperatingLossCarryforwards_04EE536D0C523141263206E20D1135AD" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Operating Loss Carryforwards</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_OperatingLossCarryforwards" xlink:label="loc_us-gaap_OperatingLossCarryforwards_04EE536D0C523141263206E20D1135AD" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OperatingLossCarryforwards_04EE536D0C523141263206E20D1135AD" xlink:to="lab_us-gaap_OperatingLossCarryforwards_04EE536D0C523141263206E20D1135AD" xlink:type="arc" />
    <link:label id="lab_us-gaap_TaxCreditCarryforwardAmount_E1F10EF62BD84578037106E20D11F2C2_terseLabel_en-US" xlink:label="lab_us-gaap_TaxCreditCarryforwardAmount_E1F10EF62BD84578037106E20D11F2C2" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Tax credit carryforwards</link:label>
    <link:label id="lab_us-gaap_TaxCreditCarryforwardAmount_E1F10EF62BD84578037106E20D11F2C2_label_en-US" xlink:label="lab_us-gaap_TaxCreditCarryforwardAmount_E1F10EF62BD84578037106E20D11F2C2" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Tax Credit Carryforward, Amount</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_TaxCreditCarryforwardAmount" xlink:label="loc_us-gaap_TaxCreditCarryforwardAmount_E1F10EF62BD84578037106E20D11F2C2" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_TaxCreditCarryforwardAmount_E1F10EF62BD84578037106E20D11F2C2" xlink:to="lab_us-gaap_TaxCreditCarryforwardAmount_E1F10EF62BD84578037106E20D11F2C2" xlink:type="arc" />
    <link:label id="lab_us-gaap_DeferredTaxAssetsTaxCreditCarryforwardsOther_A61FB0B4B84A87FB942306E20D11AA66_terseLabel_en-US" xlink:label="lab_us-gaap_DeferredTaxAssetsTaxCreditCarryforwardsOther_A61FB0B4B84A87FB942306E20D11AA66" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Other</link:label>
    <link:label id="lab_us-gaap_DeferredTaxAssetsTaxCreditCarryforwardsOther_A61FB0B4B84A87FB942306E20D11AA66_label_en-US" xlink:label="lab_us-gaap_DeferredTaxAssetsTaxCreditCarryforwardsOther_A61FB0B4B84A87FB942306E20D11AA66" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Deferred Tax Assets, Tax Credit Carryforwards, Other</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DeferredTaxAssetsTaxCreditCarryforwardsOther" xlink:label="loc_us-gaap_DeferredTaxAssetsTaxCreditCarryforwardsOther_A61FB0B4B84A87FB942306E20D11AA66" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DeferredTaxAssetsTaxCreditCarryforwardsOther_A61FB0B4B84A87FB942306E20D11AA66" xlink:to="lab_us-gaap_DeferredTaxAssetsTaxCreditCarryforwardsOther_A61FB0B4B84A87FB942306E20D11AA66" xlink:type="arc" />
    <link:label id="lab_arnc_ScheduleOfSharesActivityTableTextBlock_EB61CD917AD9221B35547C362E3BC855_terseLabel_en-US" xlink:label="lab_arnc_ScheduleOfSharesActivityTableTextBlock_EB61CD917AD9221B35547C362E3BC855" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Schedule of Share Activity</link:label>
    <link:label id="lab_arnc_ScheduleOfSharesActivityTableTextBlock_EB61CD917AD9221B35547C362E3BC855_label_en-US" xlink:label="lab_arnc_ScheduleOfSharesActivityTableTextBlock_EB61CD917AD9221B35547C362E3BC855" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Schedule Of Shares Activity Table [Text Block]</link:label>
    <link:label id="lab_arnc_ScheduleOfSharesActivityTableTextBlock_EB61CD917AD9221B35547C362E3BC855_documentation_en-US" xlink:label="lab_arnc_ScheduleOfSharesActivityTableTextBlock_EB61CD917AD9221B35547C362E3BC855" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Schedule Of Shares Activity Table [Text Block]</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_ScheduleOfSharesActivityTableTextBlock" xlink:label="loc_arnc_ScheduleOfSharesActivityTableTextBlock_EB61CD917AD9221B35547C362E3BC855" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_ScheduleOfSharesActivityTableTextBlock_EB61CD917AD9221B35547C362E3BC855" xlink:to="lab_arnc_ScheduleOfSharesActivityTableTextBlock_EB61CD917AD9221B35547C362E3BC855" xlink:type="arc" />
    <link:label id="lab_us-gaap_ScheduleOfShareBasedCompensationStockOptionsAndStockAppreciationRightsAwardActivityTableTextBlock_09CD5EC19B4F6E4229167C362E3B420C_terseLabel_en-US" xlink:label="lab_us-gaap_ScheduleOfShareBasedCompensationStockOptionsAndStockAppreciationRightsAwardActivityTableTextBlock_09CD5EC19B4F6E4229167C362E3B420C" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Schedule of Activity for Stock Options and Stock Awards</link:label>
    <link:label id="lab_us-gaap_ScheduleOfShareBasedCompensationStockOptionsAndStockAppreciationRightsAwardActivityTableTextBlock_09CD5EC19B4F6E4229167C362E3B420C_label_en-US" xlink:label="lab_us-gaap_ScheduleOfShareBasedCompensationStockOptionsAndStockAppreciationRightsAwardActivityTableTextBlock_09CD5EC19B4F6E4229167C362E3B420C" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Schedule of Share-based Compensation, Stock Options and Stock Appreciation Rights Award Activity [Table Text Block]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ScheduleOfShareBasedCompensationStockOptionsAndStockAppreciationRightsAwardActivityTableTextBlock" xlink:label="loc_us-gaap_ScheduleOfShareBasedCompensationStockOptionsAndStockAppreciationRightsAwardActivityTableTextBlock_09CD5EC19B4F6E4229167C362E3B420C" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationStockOptionsAndStockAppreciationRightsAwardActivityTableTextBlock_09CD5EC19B4F6E4229167C362E3B420C" xlink:to="lab_us-gaap_ScheduleOfShareBasedCompensationStockOptionsAndStockAppreciationRightsAwardActivityTableTextBlock_09CD5EC19B4F6E4229167C362E3B420C" xlink:type="arc" />
    <link:label id="lab_arnc_SummaryOfSignificantAccountingPoliciesTable_EEC6843FDA2B94855456DEFABAD8F33B_terseLabel_en-US" xlink:label="lab_arnc_SummaryOfSignificantAccountingPoliciesTable_EEC6843FDA2B94855456DEFABAD8F33B" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Summary Of Significant Accounting Policies [Table]</link:label>
    <link:label id="lab_arnc_SummaryOfSignificantAccountingPoliciesTable_EEC6843FDA2B94855456DEFABAD8F33B_label_en-US" xlink:label="lab_arnc_SummaryOfSignificantAccountingPoliciesTable_EEC6843FDA2B94855456DEFABAD8F33B" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Summary Of Significant Accounting Policies [Table]</link:label>
    <link:label id="lab_arnc_SummaryOfSignificantAccountingPoliciesTable_EEC6843FDA2B94855456DEFABAD8F33B_documentation_en-US" xlink:label="lab_arnc_SummaryOfSignificantAccountingPoliciesTable_EEC6843FDA2B94855456DEFABAD8F33B" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Summary Of Significant Accounting Policies [Table]</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_SummaryOfSignificantAccountingPoliciesTable" xlink:label="loc_arnc_SummaryOfSignificantAccountingPoliciesTable_EEC6843FDA2B94855456DEFABAD8F33B" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_SummaryOfSignificantAccountingPoliciesTable_EEC6843FDA2B94855456DEFABAD8F33B" xlink:to="lab_arnc_SummaryOfSignificantAccountingPoliciesTable_EEC6843FDA2B94855456DEFABAD8F33B" xlink:type="arc" />
    <link:label id="lab_arnc_ArconicFasteningSystemsMember_16ABD08BE2B866720191DEFABADA40A8_terseLabel_en-US" xlink:label="lab_arnc_ArconicFasteningSystemsMember_16ABD08BE2B866720191DEFABADA40A8" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Arconic Fastening Systems</link:label>
    <link:label id="lab_arnc_ArconicFasteningSystemsMember_16ABD08BE2B866720191DEFABADA40A8_label_en-US" xlink:label="lab_arnc_ArconicFasteningSystemsMember_16ABD08BE2B866720191DEFABADA40A8" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Arconic Fastening Systems [Member]</link:label>
    <link:label id="lab_arnc_ArconicFasteningSystemsMember_16ABD08BE2B866720191DEFABADA40A8_documentation_en-US" xlink:label="lab_arnc_ArconicFasteningSystemsMember_16ABD08BE2B866720191DEFABADA40A8" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Arconic Fastening Systems [Member]</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_ArconicFasteningSystemsMember" xlink:label="loc_arnc_ArconicFasteningSystemsMember_16ABD08BE2B866720191DEFABADA40A8" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_ArconicFasteningSystemsMember_16ABD08BE2B866720191DEFABADA40A8" xlink:to="lab_arnc_ArconicFasteningSystemsMember_16ABD08BE2B866720191DEFABADA40A8" xlink:type="arc" />
    <link:label id="lab_arnc_ArconicEngineeredStructuresMember_A2735D331153AFAED3A9DEFABADA3812_terseLabel_en-US" xlink:label="lab_arnc_ArconicEngineeredStructuresMember_A2735D331153AFAED3A9DEFABADA3812" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Arconic Engineered Structures</link:label>
    <link:label id="lab_arnc_ArconicEngineeredStructuresMember_A2735D331153AFAED3A9DEFABADA3812_label_en-US" xlink:label="lab_arnc_ArconicEngineeredStructuresMember_A2735D331153AFAED3A9DEFABADA3812" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Arconic Engineered Structures [Member]</link:label>
    <link:label id="lab_arnc_ArconicEngineeredStructuresMember_A2735D331153AFAED3A9DEFABADA3812_documentation_en-US" xlink:label="lab_arnc_ArconicEngineeredStructuresMember_A2735D331153AFAED3A9DEFABADA3812" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Arconic Engineered Structures [Member]</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_ArconicEngineeredStructuresMember" xlink:label="loc_arnc_ArconicEngineeredStructuresMember_A2735D331153AFAED3A9DEFABADA3812" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_ArconicEngineeredStructuresMember_A2735D331153AFAED3A9DEFABADA3812" xlink:to="lab_arnc_ArconicEngineeredStructuresMember_A2735D331153AFAED3A9DEFABADA3812" xlink:type="arc" />
    <link:label id="lab_arnc_DisksBusinessMember_FCBEAE895B67490771CFDEFABADB3F7C_terseLabel_en-US" xlink:label="lab_arnc_DisksBusinessMember_FCBEAE895B67490771CFDEFABADB3F7C" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Disks Asset Group</link:label>
    <link:label id="lab_arnc_DisksBusinessMember_FCBEAE895B67490771CFDEFABADB3F7C_label_en-US" xlink:label="lab_arnc_DisksBusinessMember_FCBEAE895B67490771CFDEFABADB3F7C" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Disks Business [Member]</link:label>
    <link:label id="lab_arnc_DisksBusinessMember_FCBEAE895B67490771CFDEFABADB3F7C_documentation_en-US" xlink:label="lab_arnc_DisksBusinessMember_FCBEAE895B67490771CFDEFABADB3F7C" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Disks Business [Member]</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_DisksBusinessMember" xlink:label="loc_arnc_DisksBusinessMember_FCBEAE895B67490771CFDEFABADB3F7C" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_DisksBusinessMember_FCBEAE895B67490771CFDEFABADB3F7C" xlink:to="lab_arnc_DisksBusinessMember_FCBEAE895B67490771CFDEFABADB3F7C" xlink:type="arc" />
    <link:label id="lab_arnc_AlcoaForgingAndExtrusionsMember_3F8F44ACCC9CFB839DBFDEFABADD7C83_terseLabel_en-US" xlink:label="lab_arnc_AlcoaForgingAndExtrusionsMember_3F8F44ACCC9CFB839DBFDEFABADD7C83" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Alcoa Forging and Extrusions</link:label>
    <link:label id="lab_arnc_AlcoaForgingAndExtrusionsMember_3F8F44ACCC9CFB839DBFDEFABADD7C83_label_en-US" xlink:label="lab_arnc_AlcoaForgingAndExtrusionsMember_3F8F44ACCC9CFB839DBFDEFABADD7C83" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Alcoa Forging and Extrusions [Member]</link:label>
    <link:label id="lab_arnc_AlcoaForgingAndExtrusionsMember_3F8F44ACCC9CFB839DBFDEFABADD7C83_documentation_en-US" xlink:label="lab_arnc_AlcoaForgingAndExtrusionsMember_3F8F44ACCC9CFB839DBFDEFABADD7C83" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Alcoa Forging and Extrusions [Member]</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_AlcoaForgingAndExtrusionsMember" xlink:label="loc_arnc_AlcoaForgingAndExtrusionsMember_3F8F44ACCC9CFB839DBFDEFABADD7C83" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_AlcoaForgingAndExtrusionsMember_3F8F44ACCC9CFB839DBFDEFABADD7C83" xlink:to="lab_arnc_AlcoaForgingAndExtrusionsMember_3F8F44ACCC9CFB839DBFDEFABADD7C83" xlink:type="arc" />
    <link:label id="lab_arnc_SummaryOfSignificantAccountingPoliciesLineItems_6EE3D5027CBBFB9873F7DEFABADE334D_terseLabel_en-US" xlink:label="lab_arnc_SummaryOfSignificantAccountingPoliciesLineItems_6EE3D5027CBBFB9873F7DEFABADE334D" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Summary Of Significant Accounting Policies [Line Items]</link:label>
    <link:label id="lab_arnc_SummaryOfSignificantAccountingPoliciesLineItems_6EE3D5027CBBFB9873F7DEFABADE334D_label_en-US" xlink:label="lab_arnc_SummaryOfSignificantAccountingPoliciesLineItems_6EE3D5027CBBFB9873F7DEFABADE334D" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Summary Of Significant Accounting Policies [Line Items]</link:label>
    <link:label id="lab_arnc_SummaryOfSignificantAccountingPoliciesLineItems_6EE3D5027CBBFB9873F7DEFABADE334D_documentation_en-US" xlink:label="lab_arnc_SummaryOfSignificantAccountingPoliciesLineItems_6EE3D5027CBBFB9873F7DEFABADE334D" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Summary Of Significant Accounting Policies [Line Items]</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_SummaryOfSignificantAccountingPoliciesLineItems" xlink:label="loc_arnc_SummaryOfSignificantAccountingPoliciesLineItems_6EE3D5027CBBFB9873F7DEFABADE334D" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_SummaryOfSignificantAccountingPoliciesLineItems_6EE3D5027CBBFB9873F7DEFABADE334D" xlink:to="lab_arnc_SummaryOfSignificantAccountingPoliciesLineItems_6EE3D5027CBBFB9873F7DEFABADE334D" xlink:type="arc" />
    <link:label id="lab_arnc_CashEquivalentsMaximumMaturityPeriodOfHighlyLiquidInvestments_68E333D762AD6629FE3DDEFABADE2444_terseLabel_en-US" xlink:label="lab_arnc_CashEquivalentsMaximumMaturityPeriodOfHighlyLiquidInvestments_68E333D762AD6629FE3DDEFABADE2444" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Original maturity of cash equivalents</link:label>
    <link:label id="lab_arnc_CashEquivalentsMaximumMaturityPeriodOfHighlyLiquidInvestments_68E333D762AD6629FE3DDEFABADE2444_label_en-US" xlink:label="lab_arnc_CashEquivalentsMaximumMaturityPeriodOfHighlyLiquidInvestments_68E333D762AD6629FE3DDEFABADE2444" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Cash Equivalents Maximum Maturity Period Of Highly Liquid Investments</link:label>
    <link:label id="lab_arnc_CashEquivalentsMaximumMaturityPeriodOfHighlyLiquidInvestments_68E333D762AD6629FE3DDEFABADE2444_documentation_en-US" xlink:label="lab_arnc_CashEquivalentsMaximumMaturityPeriodOfHighlyLiquidInvestments_68E333D762AD6629FE3DDEFABADE2444" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Cash equivalents maximum maturity period of highly liquid investments.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_CashEquivalentsMaximumMaturityPeriodOfHighlyLiquidInvestments" xlink:label="loc_arnc_CashEquivalentsMaximumMaturityPeriodOfHighlyLiquidInvestments_68E333D762AD6629FE3DDEFABADE2444" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_CashEquivalentsMaximumMaturityPeriodOfHighlyLiquidInvestments_68E333D762AD6629FE3DDEFABADE2444" xlink:to="lab_arnc_CashEquivalentsMaximumMaturityPeriodOfHighlyLiquidInvestments_68E333D762AD6629FE3DDEFABADE2444" xlink:type="arc" />
    <link:label id="lab_us-gaap_NumberOfReportingUnits_FA90A8520A8BFC66E07ADEFABADEF66D_terseLabel_en-US" xlink:label="lab_us-gaap_NumberOfReportingUnits_FA90A8520A8BFC66E07ADEFABADEF66D" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Number of reporting units</link:label>
    <link:label id="lab_us-gaap_NumberOfReportingUnits_FA90A8520A8BFC66E07ADEFABADEF66D_label_en-US" xlink:label="lab_us-gaap_NumberOfReportingUnits_FA90A8520A8BFC66E07ADEFABADEF66D" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Number of Reporting Units</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_NumberOfReportingUnits" xlink:label="loc_us-gaap_NumberOfReportingUnits_FA90A8520A8BFC66E07ADEFABADEF66D" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_NumberOfReportingUnits_FA90A8520A8BFC66E07ADEFABADEF66D" xlink:to="lab_us-gaap_NumberOfReportingUnits_FA90A8520A8BFC66E07ADEFABADEF66D" xlink:type="arc" />
    <link:label id="lab_arnc_PercentageOfGoodwillAllocatedToReportingUnits_82DA574EE34A72EA68DFDEFABADE7162_terseLabel_en-US" xlink:label="lab_arnc_PercentageOfGoodwillAllocatedToReportingUnits_82DA574EE34A72EA68DFDEFABADE7162" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Percentage of total goodwill allocated to two reporting units</link:label>
    <link:label id="lab_arnc_PercentageOfGoodwillAllocatedToReportingUnits_82DA574EE34A72EA68DFDEFABADE7162_label_en-US" xlink:label="lab_arnc_PercentageOfGoodwillAllocatedToReportingUnits_82DA574EE34A72EA68DFDEFABADE7162" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Percentage Of Goodwill Allocated To Reporting Units</link:label>
    <link:label id="lab_arnc_PercentageOfGoodwillAllocatedToReportingUnits_82DA574EE34A72EA68DFDEFABADE7162_documentation_en-US" xlink:label="lab_arnc_PercentageOfGoodwillAllocatedToReportingUnits_82DA574EE34A72EA68DFDEFABADE7162" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Percentage of total goodwill allocated to reporting units.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_PercentageOfGoodwillAllocatedToReportingUnits" xlink:label="loc_arnc_PercentageOfGoodwillAllocatedToReportingUnits_82DA574EE34A72EA68DFDEFABADE7162" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_PercentageOfGoodwillAllocatedToReportingUnits_82DA574EE34A72EA68DFDEFABADE7162" xlink:to="lab_arnc_PercentageOfGoodwillAllocatedToReportingUnits_82DA574EE34A72EA68DFDEFABADE7162" xlink:type="arc" />
    <link:label id="lab_arnc_NumberOfReportingUnitsForGoodwillAllocation_C123A5CF8AB2E96821D7DEFABADEB832_terseLabel_en-US" xlink:label="lab_arnc_NumberOfReportingUnitsForGoodwillAllocation_C123A5CF8AB2E96821D7DEFABADEB832" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Number of reporting units for goodwill allocation</link:label>
    <link:label id="lab_arnc_NumberOfReportingUnitsForGoodwillAllocation_C123A5CF8AB2E96821D7DEFABADEB832_label_en-US" xlink:label="lab_arnc_NumberOfReportingUnitsForGoodwillAllocation_C123A5CF8AB2E96821D7DEFABADEB832" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Number Of Reporting Units For Goodwill Allocation</link:label>
    <link:label id="lab_arnc_NumberOfReportingUnitsForGoodwillAllocation_C123A5CF8AB2E96821D7DEFABADEB832_documentation_en-US" xlink:label="lab_arnc_NumberOfReportingUnitsForGoodwillAllocation_C123A5CF8AB2E96821D7DEFABADEB832" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Number of reporting units for goodwill allocation.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_NumberOfReportingUnitsForGoodwillAllocation" xlink:label="loc_arnc_NumberOfReportingUnitsForGoodwillAllocation_C123A5CF8AB2E96821D7DEFABADEB832" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_NumberOfReportingUnitsForGoodwillAllocation_C123A5CF8AB2E96821D7DEFABADEB832" xlink:to="lab_arnc_NumberOfReportingUnitsForGoodwillAllocation_C123A5CF8AB2E96821D7DEFABADEB832" xlink:type="arc" />
    <link:label id="lab_us-gaap_Goodwill_B313CFB0882DCE4A8337DEFABADF0AF0_positiveTerseLabel_en-US" xlink:label="lab_us-gaap_Goodwill_B313CFB0882DCE4A8337DEFABADF0AF0" xlink:role="http://www.xbrl.org/2003/role/positiveTerseLabel" xlink:type="resource" xml:lang="en-US">Segment allocation, goodwill recognized</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_Goodwill" xlink:label="loc_us-gaap_Goodwill_B313CFB0882DCE4A8337DEFABADF0AF0" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_Goodwill_B313CFB0882DCE4A8337DEFABADF0AF0" xlink:to="lab_us-gaap_Goodwill_B313CFB0882DCE4A8337DEFABADF0AF0" xlink:type="arc" />
    <link:label id="lab_arnc_MinimumPercentageOfEstimatedFairValueOfReportingUnitToBeLessThanCarryingAmountOfGoodwill_17EEAA90AC24F095B75ADEFABADFE784_terseLabel_en-US" xlink:label="lab_arnc_MinimumPercentageOfEstimatedFairValueOfReportingUnitToBeLessThanCarryingAmountOfGoodwill_17EEAA90AC24F095B75ADEFABADFE784" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Minimum percentage of estimated fair value of reporting unit to be less than carrying amount of goodwill</link:label>
    <link:label id="lab_arnc_MinimumPercentageOfEstimatedFairValueOfReportingUnitToBeLessThanCarryingAmountOfGoodwill_17EEAA90AC24F095B75ADEFABADFE784_label_en-US" xlink:label="lab_arnc_MinimumPercentageOfEstimatedFairValueOfReportingUnitToBeLessThanCarryingAmountOfGoodwill_17EEAA90AC24F095B75ADEFABADFE784" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Minimum Percentage Of Estimated Fair Value Of Reporting Unit To Be Less Than Carrying Amount Of Goodwill</link:label>
    <link:label id="lab_arnc_MinimumPercentageOfEstimatedFairValueOfReportingUnitToBeLessThanCarryingAmountOfGoodwill_17EEAA90AC24F095B75ADEFABADFE784_documentation_en-US" xlink:label="lab_arnc_MinimumPercentageOfEstimatedFairValueOfReportingUnitToBeLessThanCarryingAmountOfGoodwill_17EEAA90AC24F095B75ADEFABADFE784" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Minimum percentage of estimated fair value of reporting unit to be less than carrying amount of goodwill.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_MinimumPercentageOfEstimatedFairValueOfReportingUnitToBeLessThanCarryingAmountOfGoodwill" xlink:label="loc_arnc_MinimumPercentageOfEstimatedFairValueOfReportingUnitToBeLessThanCarryingAmountOfGoodwill_17EEAA90AC24F095B75ADEFABADFE784" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_MinimumPercentageOfEstimatedFairValueOfReportingUnitToBeLessThanCarryingAmountOfGoodwill_17EEAA90AC24F095B75ADEFABADFE784" xlink:to="lab_arnc_MinimumPercentageOfEstimatedFairValueOfReportingUnitToBeLessThanCarryingAmountOfGoodwill_17EEAA90AC24F095B75ADEFABADFE784" xlink:type="arc" />
    <link:label id="lab_arnc_PeriodRequiredForOneQuantitativeImpairmentTestToBePerformedForEachReportingUnit_56AD6ACC5E70EF1C1DA5DEFABADF88BB_terseLabel_en-US" xlink:label="lab_arnc_PeriodRequiredForOneQuantitativeImpairmentTestToBePerformedForEachReportingUnit_56AD6ACC5E70EF1C1DA5DEFABADF88BB" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Period required for impairment testing of reporting units</link:label>
    <link:label id="lab_arnc_PeriodRequiredForOneQuantitativeImpairmentTestToBePerformedForEachReportingUnit_56AD6ACC5E70EF1C1DA5DEFABADF88BB_label_en-US" xlink:label="lab_arnc_PeriodRequiredForOneQuantitativeImpairmentTestToBePerformedForEachReportingUnit_56AD6ACC5E70EF1C1DA5DEFABADF88BB" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Period Required For One Quantitative Impairment Test To Be Performed For Each Reporting Unit</link:label>
    <link:label id="lab_arnc_PeriodRequiredForOneQuantitativeImpairmentTestToBePerformedForEachReportingUnit_56AD6ACC5E70EF1C1DA5DEFABADF88BB_documentation_en-US" xlink:label="lab_arnc_PeriodRequiredForOneQuantitativeImpairmentTestToBePerformedForEachReportingUnit_56AD6ACC5E70EF1C1DA5DEFABADF88BB" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Period Required For One Quantitative Impairment Test To Be Performed For Each Reporting Unit</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_PeriodRequiredForOneQuantitativeImpairmentTestToBePerformedForEachReportingUnit" xlink:label="loc_arnc_PeriodRequiredForOneQuantitativeImpairmentTestToBePerformedForEachReportingUnit_56AD6ACC5E70EF1C1DA5DEFABADF88BB" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_PeriodRequiredForOneQuantitativeImpairmentTestToBePerformedForEachReportingUnit_56AD6ACC5E70EF1C1DA5DEFABADF88BB" xlink:to="lab_arnc_PeriodRequiredForOneQuantitativeImpairmentTestToBePerformedForEachReportingUnit_56AD6ACC5E70EF1C1DA5DEFABADF88BB" xlink:type="arc" />
    <link:label id="lab_arnc_RevenueTermsOfPaymentPeriod_E86C45F0325070F1922BDEFABADFADF8_terseLabel_en-US" xlink:label="lab_arnc_RevenueTermsOfPaymentPeriod_E86C45F0325070F1922BDEFABADFADF8" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Revenue, terms of payment, period</link:label>
    <link:label id="lab_arnc_RevenueTermsOfPaymentPeriod_E86C45F0325070F1922BDEFABADFADF8_label_en-US" xlink:label="lab_arnc_RevenueTermsOfPaymentPeriod_E86C45F0325070F1922BDEFABADFADF8" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Revenue, Terms Of Payment, Period</link:label>
    <link:label id="lab_arnc_RevenueTermsOfPaymentPeriod_E86C45F0325070F1922BDEFABADFADF8_documentation_en-US" xlink:label="lab_arnc_RevenueTermsOfPaymentPeriod_E86C45F0325070F1922BDEFABADFADF8" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Revenue, Terms Of Payment, Period</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_RevenueTermsOfPaymentPeriod" xlink:label="loc_arnc_RevenueTermsOfPaymentPeriod_E86C45F0325070F1922BDEFABADFADF8" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_RevenueTermsOfPaymentPeriod_E86C45F0325070F1922BDEFABADFADF8" xlink:to="lab_arnc_RevenueTermsOfPaymentPeriod_E86C45F0325070F1922BDEFABADFADF8" xlink:type="arc" />
    <link:label id="lab_arnc_DiscontinuedOperationsBusinessesExpectedToBeDisposedWithinCertainYears_9039E2879E1BC7EAEC1BDEFABADF0460_terseLabel_en-US" xlink:label="lab_arnc_DiscontinuedOperationsBusinessesExpectedToBeDisposedWithinCertainYears_9039E2879E1BC7EAEC1BDEFABADF0460" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Businesses expected to be disposed within, years</link:label>
    <link:label id="lab_arnc_DiscontinuedOperationsBusinessesExpectedToBeDisposedWithinCertainYears_9039E2879E1BC7EAEC1BDEFABADF0460_label_en-US" xlink:label="lab_arnc_DiscontinuedOperationsBusinessesExpectedToBeDisposedWithinCertainYears_9039E2879E1BC7EAEC1BDEFABADF0460" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Discontinued Operations Businesses Expected To Be Disposed Within Certain Years</link:label>
    <link:label id="lab_arnc_DiscontinuedOperationsBusinessesExpectedToBeDisposedWithinCertainYears_9039E2879E1BC7EAEC1BDEFABADF0460_documentation_en-US" xlink:label="lab_arnc_DiscontinuedOperationsBusinessesExpectedToBeDisposedWithinCertainYears_9039E2879E1BC7EAEC1BDEFABADF0460" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Discontinued operations businesses expected to be disposed within certain years.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_DiscontinuedOperationsBusinessesExpectedToBeDisposedWithinCertainYears" xlink:label="loc_arnc_DiscontinuedOperationsBusinessesExpectedToBeDisposedWithinCertainYears_9039E2879E1BC7EAEC1BDEFABADF0460" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_DiscontinuedOperationsBusinessesExpectedToBeDisposedWithinCertainYears_9039E2879E1BC7EAEC1BDEFABADF0460" xlink:to="lab_arnc_DiscontinuedOperationsBusinessesExpectedToBeDisposedWithinCertainYears_9039E2879E1BC7EAEC1BDEFABADF0460" xlink:type="arc" />
    <link:label id="lab_us-gaap_PaymentsOfDebtExtinguishmentCosts_E5738A303DD1A67C5C0FDEFABAE0465B_terseLabel_en-US" xlink:label="lab_us-gaap_PaymentsOfDebtExtinguishmentCosts_E5738A303DD1A67C5C0FDEFABAE0465B" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Payment for debt extinguishment or debt prepayment cost</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PaymentsOfDebtExtinguishmentCosts" xlink:label="loc_us-gaap_PaymentsOfDebtExtinguishmentCosts_E5738A303DD1A67C5C0FDEFABAE0465B" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PaymentsOfDebtExtinguishmentCosts_E5738A303DD1A67C5C0FDEFABAE0465B" xlink:to="lab_us-gaap_PaymentsOfDebtExtinguishmentCosts_E5738A303DD1A67C5C0FDEFABAE0465B" xlink:type="arc" />
    <link:label id="lab_us-gaap_RestrictedCash_58B55225A57EFF7794ECDEFABAE058AE_terseLabel_en-US" xlink:label="lab_us-gaap_RestrictedCash_58B55225A57EFF7794ECDEFABAE058AE" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Restricted cash</link:label>
    <link:label id="lab_us-gaap_RestrictedCash_58B55225A57EFF7794ECDEFABAE058AE_label_en-US" xlink:label="lab_us-gaap_RestrictedCash_58B55225A57EFF7794ECDEFABAE058AE" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Restricted Cash</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RestrictedCash" xlink:label="loc_us-gaap_RestrictedCash_58B55225A57EFF7794ECDEFABAE058AE" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RestrictedCash_58B55225A57EFF7794ECDEFABAE058AE" xlink:to="lab_us-gaap_RestrictedCash_58B55225A57EFF7794ECDEFABAE058AE" xlink:type="arc" />
    <link:label id="lab_arnc_NetPeriodicBenefitCostNonservice_90B52747C228070EFE8DDEFABAE0C0C5_verboseLabel_en-US" xlink:label="lab_arnc_NetPeriodicBenefitCostNonservice_90B52747C228070EFE8DDEFABAE0C0C5" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Net periodic benefit cost, non-service</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_NetPeriodicBenefitCostNonservice" xlink:label="loc_arnc_NetPeriodicBenefitCostNonservice_90B52747C228070EFE8DDEFABAE0C0C5" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_NetPeriodicBenefitCostNonservice_90B52747C228070EFE8DDEFABAE0C0C5" xlink:to="lab_arnc_NetPeriodicBenefitCostNonservice_90B52747C228070EFE8DDEFABAE0C0C5" xlink:type="arc" />
    <link:label id="lab_arnc_TaxCutsAndJobsActOf2017IncompleteAccountingTransitionTaxForAccumulatedForeignEarningsProvisionalIncomeTaxExpense_D90F892BB8D090F19547DEFABAE06520_negatedTerseLabel_en-US" xlink:label="lab_arnc_TaxCutsAndJobsActOf2017IncompleteAccountingTransitionTaxForAccumulatedForeignEarningsProvisionalIncomeTaxExpense_D90F892BB8D090F19547DEFABAE06520" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:type="resource" xml:lang="en-US">Amount of stranded tax effects in accumulated other comprehensive income reclassified to accumulated deficit</link:label>
    <link:label id="lab_arnc_TaxCutsAndJobsActOf2017IncompleteAccountingTransitionTaxForAccumulatedForeignEarningsProvisionalIncomeTaxExpense_D90F892BB8D090F19547DEFABAE06520_label_en-US" xlink:label="lab_arnc_TaxCutsAndJobsActOf2017IncompleteAccountingTransitionTaxForAccumulatedForeignEarningsProvisionalIncomeTaxExpense_D90F892BB8D090F19547DEFABAE06520" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Tax Cuts And Jobs Act Of 2017, Incomplete Accounting, Transition Tax For Accumulated Foreign Earnings, Provisional Income Tax Expense</link:label>
    <link:label id="lab_arnc_TaxCutsAndJobsActOf2017IncompleteAccountingTransitionTaxForAccumulatedForeignEarningsProvisionalIncomeTaxExpense_D90F892BB8D090F19547DEFABAE06520_documentation_en-US" xlink:label="lab_arnc_TaxCutsAndJobsActOf2017IncompleteAccountingTransitionTaxForAccumulatedForeignEarningsProvisionalIncomeTaxExpense_D90F892BB8D090F19547DEFABAE06520" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Tax Cuts And Jobs Act Of 2017, Incomplete Accounting, Transition Tax For Accumulated Foreign Earnings, Provisional Income Tax Expense (Benefit)</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_TaxCutsAndJobsActOf2017IncompleteAccountingTransitionTaxForAccumulatedForeignEarningsProvisionalIncomeTaxExpense" xlink:label="loc_arnc_TaxCutsAndJobsActOf2017IncompleteAccountingTransitionTaxForAccumulatedForeignEarningsProvisionalIncomeTaxExpense_D90F892BB8D090F19547DEFABAE06520" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_TaxCutsAndJobsActOf2017IncompleteAccountingTransitionTaxForAccumulatedForeignEarningsProvisionalIncomeTaxExpense_D90F892BB8D090F19547DEFABAE06520" xlink:to="lab_arnc_TaxCutsAndJobsActOf2017IncompleteAccountingTransitionTaxForAccumulatedForeignEarningsProvisionalIncomeTaxExpense_D90F892BB8D090F19547DEFABAE06520" xlink:type="arc" />
    <link:label id="lab_us-gaap_OperatingLeaseRightOfUseAsset_6EA8E063936B5A15C12BDEFABAE0ED4C_terseLabel_en-US" xlink:label="lab_us-gaap_OperatingLeaseRightOfUseAsset_6EA8E063936B5A15C12BDEFABAE0ED4C" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Right-of-use asset and operating lease liability</link:label>
    <link:label id="lab_us-gaap_OperatingLeaseRightOfUseAsset_6EA8E063936B5A15C12BDEFABAE0ED4C_label_en-US" xlink:label="lab_us-gaap_OperatingLeaseRightOfUseAsset_6EA8E063936B5A15C12BDEFABAE0ED4C" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Operating Lease, Right-of-Use Asset</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_OperatingLeaseRightOfUseAsset" xlink:label="loc_us-gaap_OperatingLeaseRightOfUseAsset_6EA8E063936B5A15C12BDEFABAE0ED4C" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OperatingLeaseRightOfUseAsset_6EA8E063936B5A15C12BDEFABAE0ED4C" xlink:to="lab_us-gaap_OperatingLeaseRightOfUseAsset_6EA8E063936B5A15C12BDEFABAE0ED4C" xlink:type="arc" />
    <link:label id="lab_arnc_ScheduleOfStockOptionActivityTable_08206E81D24293B00744C968BD020942_terseLabel_en-US" xlink:label="lab_arnc_ScheduleOfStockOptionActivityTable_08206E81D24293B00744C968BD020942" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Schedule Of Stock Option Activity [Table]</link:label>
    <link:label id="lab_arnc_ScheduleOfStockOptionActivityTable_08206E81D24293B00744C968BD020942_label_en-US" xlink:label="lab_arnc_ScheduleOfStockOptionActivityTable_08206E81D24293B00744C968BD020942" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Schedule Of Stock Option Activity [Table]</link:label>
    <link:label id="lab_arnc_ScheduleOfStockOptionActivityTable_08206E81D24293B00744C968BD020942_documentation_en-US" xlink:label="lab_arnc_ScheduleOfStockOptionActivityTable_08206E81D24293B00744C968BD020942" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Schedule Of Stock Option Activity [Table]</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_ScheduleOfStockOptionActivityTable" xlink:label="loc_arnc_ScheduleOfStockOptionActivityTable_08206E81D24293B00744C968BD020942" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_ScheduleOfStockOptionActivityTable_08206E81D24293B00744C968BD020942" xlink:to="lab_arnc_ScheduleOfStockOptionActivityTable_08206E81D24293B00744C968BD020942" xlink:type="arc" />
    <link:label id="lab_arnc_ScheduleOfStockOptionActivityLineItems_66B56FE9FD3EB215B9F5C968BD03C551_terseLabel_en-US" xlink:label="lab_arnc_ScheduleOfStockOptionActivityLineItems_66B56FE9FD3EB215B9F5C968BD03C551" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Schedule Of Stock Option Activity [Line Items]</link:label>
    <link:label id="lab_arnc_ScheduleOfStockOptionActivityLineItems_66B56FE9FD3EB215B9F5C968BD03C551_label_en-US" xlink:label="lab_arnc_ScheduleOfStockOptionActivityLineItems_66B56FE9FD3EB215B9F5C968BD03C551" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Schedule Of Stock Option Activity [Line Items]</link:label>
    <link:label id="lab_arnc_ScheduleOfStockOptionActivityLineItems_66B56FE9FD3EB215B9F5C968BD03C551_documentation_en-US" xlink:label="lab_arnc_ScheduleOfStockOptionActivityLineItems_66B56FE9FD3EB215B9F5C968BD03C551" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Schedule Of Stock Option Activity [Line Items]</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_ScheduleOfStockOptionActivityLineItems" xlink:label="loc_arnc_ScheduleOfStockOptionActivityLineItems_66B56FE9FD3EB215B9F5C968BD03C551" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_ScheduleOfStockOptionActivityLineItems_66B56FE9FD3EB215B9F5C968BD03C551" xlink:to="lab_arnc_ScheduleOfStockOptionActivityLineItems_66B56FE9FD3EB215B9F5C968BD03C551" xlink:type="arc" />
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingRollForward_2CA98C76F28EAB1E5C10C968BD031F3B_terseLabel_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingRollForward_2CA98C76F28EAB1E5C10C968BD031F3B" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]</link:label>
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingRollForward_2CA98C76F28EAB1E5C10C968BD031F3B_label_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingRollForward_2CA98C76F28EAB1E5C10C968BD031F3B" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingRollForward" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingRollForward_2CA98C76F28EAB1E5C10C968BD031F3B" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingRollForward_2CA98C76F28EAB1E5C10C968BD031F3B" xlink:to="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingRollForward_2CA98C76F28EAB1E5C10C968BD031F3B" xlink:type="arc" />
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber_78C4D55C7497F6B417E4C968BD044BAC_periodStartLabel_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber_78C4D55C7497F6B417E4C968BD044BAC" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel" xlink:type="resource" xml:lang="en-US">Number of options outstanding at the beginning of the year (in shares)</link:label>
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber_78C4D55C7497F6B417E4C968BD044BAC_label_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber_78C4D55C7497F6B417E4C968BD044BAC" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber_78C4D55C7497F6B417E4C968BD044BAC" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber_78C4D55C7497F6B417E4C968BD044BAC" xlink:to="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber_78C4D55C7497F6B417E4C968BD044BAC" xlink:type="arc" />
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriod_799957F595C1FBCF7D9CC968BD0486FB_terseLabel_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriod_799957F595C1FBCF7D9CC968BD0486FB" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Number of options granted (in shares)</link:label>
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriod_799957F595C1FBCF7D9CC968BD0486FB_label_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriod_799957F595C1FBCF7D9CC968BD0486FB" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Net of Forfeitures</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriod" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriod_799957F595C1FBCF7D9CC968BD0486FB" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriod_799957F595C1FBCF7D9CC968BD0486FB" xlink:to="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriod_799957F595C1FBCF7D9CC968BD0486FB" xlink:type="arc" />
    <link:label id="lab_us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised_1E5B3F0BB0DF0BFBDD95C968BD04BF33_negatedLabel_en-US" xlink:label="lab_us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised_1E5B3F0BB0DF0BFBDD95C968BD04BF33" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xml:lang="en-US">Number of options exercised (in shares)</link:label>
    <link:label id="lab_us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised_1E5B3F0BB0DF0BFBDD95C968BD04BF33_label_en-US" xlink:label="lab_us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised_1E5B3F0BB0DF0BFBDD95C968BD04BF33" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised" xlink:label="loc_us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised_1E5B3F0BB0DF0BFBDD95C968BD04BF33" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised_1E5B3F0BB0DF0BFBDD95C968BD04BF33" xlink:to="lab_us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised_1E5B3F0BB0DF0BFBDD95C968BD04BF33" xlink:type="arc" />
    <link:label id="lab_arnc_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsConverted_2B10E513D92A3C6DB550C968BD054342_negatedTerseLabel_en-US" xlink:label="lab_arnc_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsConverted_2B10E513D92A3C6DB550C968BD054342" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:type="resource" xml:lang="en-US">Number of options converted (in shares)</link:label>
    <link:label id="lab_arnc_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsConverted_2B10E513D92A3C6DB550C968BD054342_label_en-US" xlink:label="lab_arnc_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsConverted_2B10E513D92A3C6DB550C968BD054342" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Share Based Compensation Arrangement By Share Based Payment Award Options Converted</link:label>
    <link:label id="lab_arnc_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsConverted_2B10E513D92A3C6DB550C968BD054342_documentation_en-US" xlink:label="lab_arnc_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsConverted_2B10E513D92A3C6DB550C968BD054342" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Share Based Compensation Arrangement By Share Based Payment Award Options Converted</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsConverted" xlink:label="loc_arnc_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsConverted_2B10E513D92A3C6DB550C968BD054342" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsConverted_2B10E513D92A3C6DB550C968BD054342" xlink:to="lab_arnc_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsConverted_2B10E513D92A3C6DB550C968BD054342" xlink:type="arc" />
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresAndExpirationsInPeriod_169FC6FE3315353D0B04C968BD05B168_negatedLabel_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresAndExpirationsInPeriod_169FC6FE3315353D0B04C968BD05B168" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xml:lang="en-US">Number of options expired or forfeited (in shares)</link:label>
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresAndExpirationsInPeriod_169FC6FE3315353D0B04C968BD05B168_label_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresAndExpirationsInPeriod_169FC6FE3315353D0B04C968BD05B168" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Share-based Compensation Arrangement by Share-based Payment Award, Options, Forfeitures and Expirations in Period</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresAndExpirationsInPeriod" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresAndExpirationsInPeriod_169FC6FE3315353D0B04C968BD05B168" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresAndExpirationsInPeriod_169FC6FE3315353D0B04C968BD05B168" xlink:to="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresAndExpirationsInPeriod_169FC6FE3315353D0B04C968BD05B168" xlink:type="arc" />
    <link:label id="lab_arnc_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsPerformanceSharesActualPayout_8FD7227FDC07AF72964FC968BD0530CD_negatedTerseLabel_en-US" xlink:label="lab_arnc_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsPerformanceSharesActualPayout_8FD7227FDC07AF72964FC968BD0530CD" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:type="resource" xml:lang="en-US">Performance share adjustment (in shares)</link:label>
    <link:label id="lab_arnc_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsPerformanceSharesActualPayout_8FD7227FDC07AF72964FC968BD0530CD_label_en-US" xlink:label="lab_arnc_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsPerformanceSharesActualPayout_8FD7227FDC07AF72964FC968BD0530CD" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Performance Shares Actual Payout</link:label>
    <link:label id="lab_arnc_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsPerformanceSharesActualPayout_8FD7227FDC07AF72964FC968BD0530CD_documentation_en-US" xlink:label="lab_arnc_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsPerformanceSharesActualPayout_8FD7227FDC07AF72964FC968BD0530CD" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Performance Shares Actual Payout</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsPerformanceSharesActualPayout" xlink:label="loc_arnc_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsPerformanceSharesActualPayout_8FD7227FDC07AF72964FC968BD0530CD" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsPerformanceSharesActualPayout_8FD7227FDC07AF72964FC968BD0530CD" xlink:to="lab_arnc_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsPerformanceSharesActualPayout_8FD7227FDC07AF72964FC968BD0530CD" xlink:type="arc" />
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber_7E7D8E924EFDBE6CB5C9C971CF3EEDC1_periodEndLabel_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber_7E7D8E924EFDBE6CB5C9C971CF3EEDC1" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel" xlink:type="resource" xml:lang="en-US">Number of options outstanding at the end of the year (in shares)</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber_7E7D8E924EFDBE6CB5C9C971CF3EEDC1" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber_7E7D8E924EFDBE6CB5C9C971CF3EEDC1" xlink:to="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber_7E7D8E924EFDBE6CB5C9C971CF3EEDC1" xlink:type="arc" />
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePriceRollforward_08AA7567347DF96AC612C968BD05CDAE_terseLabel_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePriceRollforward_08AA7567347DF96AC612C968BD05CDAE" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Abstract]</link:label>
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePriceRollforward_08AA7567347DF96AC612C968BD05CDAE_label_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePriceRollforward_08AA7567347DF96AC612C968BD05CDAE" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Abstract]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePriceRollforward" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePriceRollforward_08AA7567347DF96AC612C968BD05CDAE" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePriceRollforward_08AA7567347DF96AC612C968BD05CDAE" xlink:to="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePriceRollforward_08AA7567347DF96AC612C968BD05CDAE" xlink:type="arc" />
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice_7C73AE4D75039F27DDF7C968BD0526EF_periodStartLabel_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice_7C73AE4D75039F27DDF7C968BD0526EF" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel" xlink:type="resource" xml:lang="en-US">Weighted average exercise price, outstanding beginning of year (in usd per share)</link:label>
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice_7C73AE4D75039F27DDF7C968BD0526EF_label_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice_7C73AE4D75039F27DDF7C968BD0526EF" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice_7C73AE4D75039F27DDF7C968BD0526EF" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice_7C73AE4D75039F27DDF7C968BD0526EF" xlink:to="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice_7C73AE4D75039F27DDF7C968BD0526EF" xlink:type="arc" />
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice_3FD199913B3E474FDDE4C968BD065E25_terseLabel_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice_3FD199913B3E474FDDE4C968BD065E25" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Weighted average exercise price, granted (in usd per share)</link:label>
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice_3FD199913B3E474FDDE4C968BD065E25_label_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice_3FD199913B3E474FDDE4C968BD065E25" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice_3FD199913B3E474FDDE4C968BD065E25" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice_3FD199913B3E474FDDE4C968BD065E25" xlink:to="lab_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice_3FD199913B3E474FDDE4C968BD065E25" xlink:type="arc" />
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice_963521971890B5734877C968BD06C78B_terseLabel_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice_963521971890B5734877C968BD06C78B" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Weighted average exercise price, exercised (in usd per share)</link:label>
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice_963521971890B5734877C968BD06C78B_label_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice_963521971890B5734877C968BD06C78B" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Share-based Compensation Arrangements by Share-based Payment Award, Options, Exercises in Period, Weighted Average Exercise Price</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice_963521971890B5734877C968BD06C78B" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice_963521971890B5734877C968BD06C78B" xlink:to="lab_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice_963521971890B5734877C968BD06C78B" xlink:type="arc" />
    <link:label id="lab_arnc_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsConvertedOrTransferredInPeriodWeightedAverageExercisePrice_73AC6922F0BFFF51D476C968BD06B0D2_terseLabel_en-US" xlink:label="lab_arnc_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsConvertedOrTransferredInPeriodWeightedAverageExercisePrice_73AC6922F0BFFF51D476C968BD06B0D2" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Weighted average exercise price, converted (in usd per share)</link:label>
    <link:label id="lab_arnc_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsConvertedOrTransferredInPeriodWeightedAverageExercisePrice_73AC6922F0BFFF51D476C968BD06B0D2_label_en-US" xlink:label="lab_arnc_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsConvertedOrTransferredInPeriodWeightedAverageExercisePrice_73AC6922F0BFFF51D476C968BD06B0D2" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Share Based Compensation Arrangements By Share Based Payment Award Options Converted Or Transferred In Period Weighted Average Exercise Price</link:label>
    <link:label id="lab_arnc_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsConvertedOrTransferredInPeriodWeightedAverageExercisePrice_73AC6922F0BFFF51D476C968BD06B0D2_documentation_en-US" xlink:label="lab_arnc_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsConvertedOrTransferredInPeriodWeightedAverageExercisePrice_73AC6922F0BFFF51D476C968BD06B0D2" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Share Based Compensation Arrangements By Share Based Payment Award Options Converted Or Transferred In Period Weighted Average Exercise Price</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsConvertedOrTransferredInPeriodWeightedAverageExercisePrice" xlink:label="loc_arnc_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsConvertedOrTransferredInPeriodWeightedAverageExercisePrice_73AC6922F0BFFF51D476C968BD06B0D2" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsConvertedOrTransferredInPeriodWeightedAverageExercisePrice_73AC6922F0BFFF51D476C968BD06B0D2" xlink:to="lab_arnc_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsConvertedOrTransferredInPeriodWeightedAverageExercisePrice_73AC6922F0BFFF51D476C968BD06B0D2" xlink:type="arc" />
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresAndExpirationsInPeriodWeightedAverageExercisePrice_3B422F532274E8A44A59C968BD076931_terseLabel_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresAndExpirationsInPeriodWeightedAverageExercisePrice_3B422F532274E8A44A59C968BD076931" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Weighted average exercise price, expired or forfeited (in usd per share)</link:label>
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresAndExpirationsInPeriodWeightedAverageExercisePrice_3B422F532274E8A44A59C968BD076931_label_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresAndExpirationsInPeriodWeightedAverageExercisePrice_3B422F532274E8A44A59C968BD076931" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Share-based Compensation Arrangement by Share-based Payment Award, Options, Forfeitures and Expirations in Period, Weighted Average Exercise Price</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresAndExpirationsInPeriodWeightedAverageExercisePrice" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresAndExpirationsInPeriodWeightedAverageExercisePrice_3B422F532274E8A44A59C968BD076931" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresAndExpirationsInPeriodWeightedAverageExercisePrice_3B422F532274E8A44A59C968BD076931" xlink:to="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresAndExpirationsInPeriodWeightedAverageExercisePrice_3B422F532274E8A44A59C968BD076931" xlink:type="arc" />
    <link:label id="lab_arnc_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsPerformanceAdjustmentWeightedAverageGrantDateFairValue_C0084EFBBAFA500A0186C968BD071972_terseLabel_en-US" xlink:label="lab_arnc_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsPerformanceAdjustmentWeightedAverageGrantDateFairValue_C0084EFBBAFA500A0186C968BD071972" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Weighted average exercise price, performance share adjustment (in usd per share)</link:label>
    <link:label id="lab_arnc_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsPerformanceAdjustmentWeightedAverageGrantDateFairValue_C0084EFBBAFA500A0186C968BD071972_label_en-US" xlink:label="lab_arnc_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsPerformanceAdjustmentWeightedAverageGrantDateFairValue_C0084EFBBAFA500A0186C968BD071972" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Performance Adjustment Weighted Average Grant Date Fair Value</link:label>
    <link:label id="lab_arnc_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsPerformanceAdjustmentWeightedAverageGrantDateFairValue_C0084EFBBAFA500A0186C968BD071972_documentation_en-US" xlink:label="lab_arnc_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsPerformanceAdjustmentWeightedAverageGrantDateFairValue_C0084EFBBAFA500A0186C968BD071972" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Performance Adjustment Weighted Average Grant Date Fair Value</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsPerformanceAdjustmentWeightedAverageGrantDateFairValue" xlink:label="loc_arnc_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsPerformanceAdjustmentWeightedAverageGrantDateFairValue_C0084EFBBAFA500A0186C968BD071972" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsPerformanceAdjustmentWeightedAverageGrantDateFairValue_C0084EFBBAFA500A0186C968BD071972" xlink:to="lab_arnc_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsPerformanceAdjustmentWeightedAverageGrantDateFairValue_C0084EFBBAFA500A0186C968BD071972" xlink:type="arc" />
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice_1DF1C3E3C25A985D8C37C9727CB4B37E_periodEndLabel_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice_1DF1C3E3C25A985D8C37C9727CB4B37E" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel" xlink:type="resource" xml:lang="en-US">Weighted average exercise price, outstanding end of year (in usd per share)</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice_1DF1C3E3C25A985D8C37C9727CB4B37E" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice_1DF1C3E3C25A985D8C37C9727CB4B37E" xlink:to="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice_1DF1C3E3C25A985D8C37C9727CB4B37E" xlink:type="arc" />
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward_926DA04F46BE3FBE5DECC968BD079B0C_terseLabel_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward_926DA04F46BE3FBE5DECC968BD079B0C" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]</link:label>
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward_926DA04F46BE3FBE5DECC968BD079B0C_label_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward_926DA04F46BE3FBE5DECC968BD079B0C" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward_926DA04F46BE3FBE5DECC968BD079B0C" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward_926DA04F46BE3FBE5DECC968BD079B0C" xlink:to="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward_926DA04F46BE3FBE5DECC968BD079B0C" xlink:type="arc" />
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber_E1229F944AE028C80349C968BD07B1C7_periodStartLabel_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber_E1229F944AE028C80349C968BD07B1C7" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel" xlink:type="resource" xml:lang="en-US">Number of awards, outstanding beginning of year (in shares)</link:label>
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber_E1229F944AE028C80349C968BD07B1C7_label_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber_E1229F944AE028C80349C968BD07B1C7" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber_E1229F944AE028C80349C968BD07B1C7" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber_E1229F944AE028C80349C968BD07B1C7" xlink:to="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber_E1229F944AE028C80349C968BD07B1C7" xlink:type="arc" />
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod_60CCC65EFB314D5DE1F3C968BD0712A3_terseLabel_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod_60CCC65EFB314D5DE1F3C968BD0712A3" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Number of awards, granted (in shares)</link:label>
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod_60CCC65EFB314D5DE1F3C968BD0712A3_label_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod_60CCC65EFB314D5DE1F3C968BD0712A3" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod_60CCC65EFB314D5DE1F3C968BD0712A3" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod_60CCC65EFB314D5DE1F3C968BD0712A3" xlink:to="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod_60CCC65EFB314D5DE1F3C968BD0712A3" xlink:type="arc" />
    <link:label id="lab_arnc_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsExercisedInPeriod_F40D7DA7D365DCF38CB3C968BD0829C9_negatedTerseLabel_en-US" xlink:label="lab_arnc_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsExercisedInPeriod_F40D7DA7D365DCF38CB3C968BD0829C9" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:type="resource" xml:lang="en-US">Number of awards, exercised (in shares)</link:label>
    <link:label id="lab_arnc_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsExercisedInPeriod_F40D7DA7D365DCF38CB3C968BD0829C9_label_en-US" xlink:label="lab_arnc_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsExercisedInPeriod_F40D7DA7D365DCF38CB3C968BD0829C9" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Exercised In Period</link:label>
    <link:label id="lab_arnc_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsExercisedInPeriod_F40D7DA7D365DCF38CB3C968BD0829C9_documentation_en-US" xlink:label="lab_arnc_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsExercisedInPeriod_F40D7DA7D365DCF38CB3C968BD0829C9" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Exercised In Period</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsExercisedInPeriod" xlink:label="loc_arnc_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsExercisedInPeriod_F40D7DA7D365DCF38CB3C968BD0829C9" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsExercisedInPeriod_F40D7DA7D365DCF38CB3C968BD0829C9" xlink:to="lab_arnc_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsExercisedInPeriod_F40D7DA7D365DCF38CB3C968BD0829C9" xlink:type="arc" />
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod_245FFC7440E9B12BB0B8C968BD080BA6_negatedLabel_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod_245FFC7440E9B12BB0B8C968BD080BA6" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xml:lang="en-US">Number of awards, converted (in shares)</link:label>
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod_245FFC7440E9B12BB0B8C968BD080BA6_label_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod_245FFC7440E9B12BB0B8C968BD080BA6" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod_245FFC7440E9B12BB0B8C968BD080BA6" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod_245FFC7440E9B12BB0B8C968BD080BA6" xlink:to="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod_245FFC7440E9B12BB0B8C968BD080BA6" xlink:type="arc" />
    <link:label id="lab_arnc_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedAndExpirationsInPeriod_45F3E48A1D221BB14761C968BD086FF7_negatedLabel_en-US" xlink:label="lab_arnc_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedAndExpirationsInPeriod_45F3E48A1D221BB14761C968BD086FF7" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xml:lang="en-US">Number of awards, expired or forfeited (in shares)</link:label>
    <link:label id="lab_arnc_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedAndExpirationsInPeriod_45F3E48A1D221BB14761C968BD086FF7_label_en-US" xlink:label="lab_arnc_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedAndExpirationsInPeriod_45F3E48A1D221BB14761C968BD086FF7" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Forfeited And Expirations In Period</link:label>
    <link:label id="lab_arnc_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedAndExpirationsInPeriod_45F3E48A1D221BB14761C968BD086FF7_documentation_en-US" xlink:label="lab_arnc_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedAndExpirationsInPeriod_45F3E48A1D221BB14761C968BD086FF7" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Forfeited And Expirations In Period</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedAndExpirationsInPeriod" xlink:label="loc_arnc_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedAndExpirationsInPeriod_45F3E48A1D221BB14761C968BD086FF7" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedAndExpirationsInPeriod_45F3E48A1D221BB14761C968BD086FF7" xlink:to="lab_arnc_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedAndExpirationsInPeriod_45F3E48A1D221BB14761C968BD086FF7" xlink:type="arc" />
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsPeriodIncreaseDecrease_BB2E338EA5595E5F938BC968BD08B985_negatedLabel_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsPeriodIncreaseDecrease_BB2E338EA5595E5F938BC968BD08B985" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xml:lang="en-US">Number of awards, performance share adjustment (in shares)</link:label>
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsPeriodIncreaseDecrease_BB2E338EA5595E5F938BC968BD08B985_label_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsPeriodIncreaseDecrease_BB2E338EA5595E5F938BC968BD08B985" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Period Increase (Decrease)</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsPeriodIncreaseDecrease" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsPeriodIncreaseDecrease_BB2E338EA5595E5F938BC968BD08B985" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsPeriodIncreaseDecrease_BB2E338EA5595E5F938BC968BD08B985" xlink:to="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsPeriodIncreaseDecrease_BB2E338EA5595E5F938BC968BD08B985" xlink:type="arc" />
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber_9C6D102EE1B49ED0BBB9C968BD09572B_periodEndLabel_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber_9C6D102EE1B49ED0BBB9C968BD09572B" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel" xlink:type="resource" xml:lang="en-US">Number of awards, outstanding end of year (in shares)</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber_9C6D102EE1B49ED0BBB9C968BD09572B" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber_9C6D102EE1B49ED0BBB9C968BD09572B" xlink:to="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber_9C6D102EE1B49ED0BBB9C968BD09572B" xlink:type="arc" />
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValueRollForward_2635490D7B143DD9F6A0C968BD09F18D_terseLabel_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValueRollForward_2635490D7B143DD9F6A0C968BD09F18D" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]</link:label>
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValueRollForward_2635490D7B143DD9F6A0C968BD09F18D_label_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValueRollForward_2635490D7B143DD9F6A0C968BD09F18D" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValueRollForward" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValueRollForward_2635490D7B143DD9F6A0C968BD09F18D" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValueRollForward_2635490D7B143DD9F6A0C968BD09F18D" xlink:to="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValueRollForward_2635490D7B143DD9F6A0C968BD09F18D" xlink:type="arc" />
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue_41B2F8697A25FE4A7DAFC968BD09AECF_periodStartLabel_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue_41B2F8697A25FE4A7DAFC968BD09AECF" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel" xlink:type="resource" xml:lang="en-US">Weighted average FMV per award, outstanding beginning of year (in usd per share)</link:label>
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue_41B2F8697A25FE4A7DAFC968BD09AECF_label_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue_41B2F8697A25FE4A7DAFC968BD09AECF" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue_41B2F8697A25FE4A7DAFC968BD09AECF" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue_41B2F8697A25FE4A7DAFC968BD09AECF" xlink:to="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue_41B2F8697A25FE4A7DAFC968BD09AECF" xlink:type="arc" />
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue_597994FC666C60CF276EC968BD09538E_terseLabel_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue_597994FC666C60CF276EC968BD09538E" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Weighted average FMV per award, granted (in usd per share)</link:label>
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue_597994FC666C60CF276EC968BD09538E_label_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue_597994FC666C60CF276EC968BD09538E" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue_597994FC666C60CF276EC968BD09538E" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue_597994FC666C60CF276EC968BD09538E" xlink:to="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue_597994FC666C60CF276EC968BD09538E" xlink:type="arc" />
    <link:label id="lab_arnc_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsExercisedInPeriodWeightedAverageGrantDateFairValue_9FE137D49AD721F66C0CC968BD097724_terseLabel_en-US" xlink:label="lab_arnc_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsExercisedInPeriodWeightedAverageGrantDateFairValue_9FE137D49AD721F66C0CC968BD097724" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Weighted average FMV per award, exercised (in usd per share)</link:label>
    <link:label id="lab_arnc_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsExercisedInPeriodWeightedAverageGrantDateFairValue_9FE137D49AD721F66C0CC968BD097724_label_en-US" xlink:label="lab_arnc_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsExercisedInPeriodWeightedAverageGrantDateFairValue_9FE137D49AD721F66C0CC968BD097724" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Exercised In Period Weighted Average Grant Date Fair Value</link:label>
    <link:label id="lab_arnc_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsExercisedInPeriodWeightedAverageGrantDateFairValue_9FE137D49AD721F66C0CC968BD097724_documentation_en-US" xlink:label="lab_arnc_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsExercisedInPeriodWeightedAverageGrantDateFairValue_9FE137D49AD721F66C0CC968BD097724" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Exercised In Period Weighted Average Grant Date Fair Value</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsExercisedInPeriodWeightedAverageGrantDateFairValue" xlink:label="loc_arnc_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsExercisedInPeriodWeightedAverageGrantDateFairValue_9FE137D49AD721F66C0CC968BD097724" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsExercisedInPeriodWeightedAverageGrantDateFairValue_9FE137D49AD721F66C0CC968BD097724" xlink:to="lab_arnc_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsExercisedInPeriodWeightedAverageGrantDateFairValue_9FE137D49AD721F66C0CC968BD097724" xlink:type="arc" />
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodWeightedAverageGrantDateFairValue_72C688BFAE1924E59582C968BD0AE8AA_terseLabel_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodWeightedAverageGrantDateFairValue_72C688BFAE1924E59582C968BD0AE8AA" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Weighted average FMV per award, converted (in usd per share)</link:label>
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodWeightedAverageGrantDateFairValue_72C688BFAE1924E59582C968BD0AE8AA_label_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodWeightedAverageGrantDateFairValue_72C688BFAE1924E59582C968BD0AE8AA" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Weighted Average Grant Date Fair Value</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodWeightedAverageGrantDateFairValue" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodWeightedAverageGrantDateFairValue_72C688BFAE1924E59582C968BD0AE8AA" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodWeightedAverageGrantDateFairValue_72C688BFAE1924E59582C968BD0AE8AA" xlink:to="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodWeightedAverageGrantDateFairValue_72C688BFAE1924E59582C968BD0AE8AA" xlink:type="arc" />
    <link:label id="lab_arnc_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeituresAndExpiredWeightedAverageGrantDateFairValue_992EF2524D05494DC10CC968BD0AB941_terseLabel_en-US" xlink:label="lab_arnc_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeituresAndExpiredWeightedAverageGrantDateFairValue_992EF2524D05494DC10CC968BD0AB941" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Weighted average FMV per award, expired or forfeited (in usd per share)</link:label>
    <link:label id="lab_arnc_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeituresAndExpiredWeightedAverageGrantDateFairValue_992EF2524D05494DC10CC968BD0AB941_label_en-US" xlink:label="lab_arnc_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeituresAndExpiredWeightedAverageGrantDateFairValue_992EF2524D05494DC10CC968BD0AB941" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Forfeitures And Expired Weighted Average Grant Date Fair Value</link:label>
    <link:label id="lab_arnc_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeituresAndExpiredWeightedAverageGrantDateFairValue_992EF2524D05494DC10CC968BD0AB941_documentation_en-US" xlink:label="lab_arnc_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeituresAndExpiredWeightedAverageGrantDateFairValue_992EF2524D05494DC10CC968BD0AB941" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Forfeitures And Expired Weighted Average Grant Date Fair Value</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeituresAndExpiredWeightedAverageGrantDateFairValue" xlink:label="loc_arnc_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeituresAndExpiredWeightedAverageGrantDateFairValue_992EF2524D05494DC10CC968BD0AB941" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeituresAndExpiredWeightedAverageGrantDateFairValue_992EF2524D05494DC10CC968BD0AB941" xlink:to="lab_arnc_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeituresAndExpiredWeightedAverageGrantDateFairValue_992EF2524D05494DC10CC968BD0AB941" xlink:type="arc" />
    <link:label id="lab_arnc_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsPerformanceShareAdjustment_F5295FB8F265E74C5D93C968BD0AC170_terseLabel_en-US" xlink:label="lab_arnc_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsPerformanceShareAdjustment_F5295FB8F265E74C5D93C968BD0AC170" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Weighted average FMV per award, performance share adjustment (in usd per share)</link:label>
    <link:label id="lab_arnc_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsPerformanceShareAdjustment_F5295FB8F265E74C5D93C968BD0AC170_label_en-US" xlink:label="lab_arnc_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsPerformanceShareAdjustment_F5295FB8F265E74C5D93C968BD0AC170" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Performance Share Adjustment</link:label>
    <link:label id="lab_arnc_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsPerformanceShareAdjustment_F5295FB8F265E74C5D93C968BD0AC170_documentation_en-US" xlink:label="lab_arnc_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsPerformanceShareAdjustment_F5295FB8F265E74C5D93C968BD0AC170" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Share based compensation arrangement by share based payment award equity instruments other than options, performance share adjustment.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsPerformanceShareAdjustment" xlink:label="loc_arnc_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsPerformanceShareAdjustment_F5295FB8F265E74C5D93C968BD0AC170" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsPerformanceShareAdjustment_F5295FB8F265E74C5D93C968BD0AC170" xlink:to="lab_arnc_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsPerformanceShareAdjustment_F5295FB8F265E74C5D93C968BD0AC170" xlink:type="arc" />
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue_E46800508341EE1022B6C968BD0BD4C5_periodEndLabel_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue_E46800508341EE1022B6C968BD0BD4C5" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel" xlink:type="resource" xml:lang="en-US">Weighted average FMV per award, outstanding, end of year (in usd per share)</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue_E46800508341EE1022B6C968BD0BD4C5" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue_E46800508341EE1022B6C968BD0BD4C5" xlink:to="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue_E46800508341EE1022B6C968BD0BD4C5" xlink:type="arc" />
    <link:label id="lab_us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTable_6FBBB69E49EEF289AEA0E248CAF460B8_terseLabel_en-US" xlink:label="lab_us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTable_6FBBB69E49EEF289AEA0E248CAF460B8" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Schedule of Accounts, Notes, Loans and Financing Receivable [Table]</link:label>
    <link:label id="lab_us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTable_6FBBB69E49EEF289AEA0E248CAF460B8_label_en-US" xlink:label="lab_us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTable_6FBBB69E49EEF289AEA0E248CAF460B8" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Schedule of Accounts, Notes, Loans and Financing Receivable [Table]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTable" xlink:label="loc_us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTable_6FBBB69E49EEF289AEA0E248CAF460B8" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTable_6FBBB69E49EEF289AEA0E248CAF460B8" xlink:to="lab_us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTable_6FBBB69E49EEF289AEA0E248CAF460B8" xlink:type="arc" />
    <link:label id="lab_us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis_1E18D0385358B987832CE248CAF45815_terseLabel_en-US" xlink:label="lab_us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis_1E18D0385358B987832CE248CAF45815" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Receivable Type [Axis]</link:label>
    <link:label id="lab_us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis_1E18D0385358B987832CE248CAF45815_label_en-US" xlink:label="lab_us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis_1E18D0385358B987832CE248CAF45815" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Receivable Type [Axis]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis" xlink:label="loc_us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis_1E18D0385358B987832CE248CAF45815" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis_1E18D0385358B987832CE248CAF45815" xlink:to="lab_us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis_1E18D0385358B987832CE248CAF45815" xlink:type="arc" />
    <link:label id="lab_us-gaap_ReceivableTypeDomain_C4BE2ED23128CB814099E248CAF47BDF_terseLabel_en-US" xlink:label="lab_us-gaap_ReceivableTypeDomain_C4BE2ED23128CB814099E248CAF47BDF" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Receivable [Domain]</link:label>
    <link:label id="lab_us-gaap_ReceivableTypeDomain_C4BE2ED23128CB814099E248CAF47BDF_label_en-US" xlink:label="lab_us-gaap_ReceivableTypeDomain_C4BE2ED23128CB814099E248CAF47BDF" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Receivable [Domain]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ReceivableTypeDomain" xlink:label="loc_us-gaap_ReceivableTypeDomain_C4BE2ED23128CB814099E248CAF47BDF" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ReceivableTypeDomain_C4BE2ED23128CB814099E248CAF47BDF" xlink:to="lab_us-gaap_ReceivableTypeDomain_C4BE2ED23128CB814099E248CAF47BDF" xlink:type="arc" />
    <link:label id="lab_arnc_ReceivablesFromCustomersMember_3DCCB586EE8FC5D13977E248CAF4D57E_terseLabel_en-US" xlink:label="lab_arnc_ReceivablesFromCustomersMember_3DCCB586EE8FC5D13977E248CAF4D57E" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Customer receivables</link:label>
    <link:label id="lab_arnc_ReceivablesFromCustomersMember_3DCCB586EE8FC5D13977E248CAF4D57E_label_en-US" xlink:label="lab_arnc_ReceivablesFromCustomersMember_3DCCB586EE8FC5D13977E248CAF4D57E" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Receivables From Customers [Member]</link:label>
    <link:label id="lab_arnc_ReceivablesFromCustomersMember_3DCCB586EE8FC5D13977E248CAF4D57E_documentation_en-US" xlink:label="lab_arnc_ReceivablesFromCustomersMember_3DCCB586EE8FC5D13977E248CAF4D57E" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Receivables from customers.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_ReceivablesFromCustomersMember" xlink:label="loc_arnc_ReceivablesFromCustomersMember_3DCCB586EE8FC5D13977E248CAF4D57E" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_ReceivablesFromCustomersMember_3DCCB586EE8FC5D13977E248CAF4D57E" xlink:to="lab_arnc_ReceivablesFromCustomersMember_3DCCB586EE8FC5D13977E248CAF4D57E" xlink:type="arc" />
    <link:label id="lab_arnc_OtherReceivablesMember_7F82732985DF1925CE8AE248CAF4252A_terseLabel_en-US" xlink:label="lab_arnc_OtherReceivablesMember_7F82732985DF1925CE8AE248CAF4252A" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Other receivables</link:label>
    <link:label id="lab_arnc_OtherReceivablesMember_7F82732985DF1925CE8AE248CAF4252A_label_en-US" xlink:label="lab_arnc_OtherReceivablesMember_7F82732985DF1925CE8AE248CAF4252A" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Other Receivables [Member]</link:label>
    <link:label id="lab_arnc_OtherReceivablesMember_7F82732985DF1925CE8AE248CAF4252A_documentation_en-US" xlink:label="lab_arnc_OtherReceivablesMember_7F82732985DF1925CE8AE248CAF4252A" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Other Receivables [Member]</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_OtherReceivablesMember" xlink:label="loc_arnc_OtherReceivablesMember_7F82732985DF1925CE8AE248CAF4252A" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_OtherReceivablesMember_7F82732985DF1925CE8AE248CAF4252A" xlink:to="lab_arnc_OtherReceivablesMember_7F82732985DF1925CE8AE248CAF4252A" xlink:type="arc" />
    <link:label id="lab_us-gaap_AccountsNotesAndLoansReceivableLineItems_4AD437BFF13363D4708BE248CAF479B2_terseLabel_en-US" xlink:label="lab_us-gaap_AccountsNotesAndLoansReceivableLineItems_4AD437BFF13363D4708BE248CAF479B2" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Accounts, Notes, Loans and Financing Receivable [Line Items]</link:label>
    <link:label id="lab_us-gaap_AccountsNotesAndLoansReceivableLineItems_4AD437BFF13363D4708BE248CAF479B2_label_en-US" xlink:label="lab_us-gaap_AccountsNotesAndLoansReceivableLineItems_4AD437BFF13363D4708BE248CAF479B2" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Accounts, Notes, Loans and Financing Receivable [Line Items]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AccountsNotesAndLoansReceivableLineItems" xlink:label="loc_us-gaap_AccountsNotesAndLoansReceivableLineItems_4AD437BFF13363D4708BE248CAF479B2" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AccountsNotesAndLoansReceivableLineItems_4AD437BFF13363D4708BE248CAF479B2" xlink:to="lab_us-gaap_AccountsNotesAndLoansReceivableLineItems_4AD437BFF13363D4708BE248CAF479B2" xlink:type="arc" />
    <link:label id="lab_us-gaap_AllowanceForDoubtfulAccountsReceivableRollforward_50B948DEAFA7EF897B6BE248CAF8CA38_terseLabel_en-US" xlink:label="lab_us-gaap_AllowanceForDoubtfulAccountsReceivableRollforward_50B948DEAFA7EF897B6BE248CAF8CA38" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Allowance for Doubtful Accounts Receivable [Roll Forward]</link:label>
    <link:label id="lab_us-gaap_AllowanceForDoubtfulAccountsReceivableRollforward_50B948DEAFA7EF897B6BE248CAF8CA38_label_en-US" xlink:label="lab_us-gaap_AllowanceForDoubtfulAccountsReceivableRollforward_50B948DEAFA7EF897B6BE248CAF8CA38" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Allowance for Doubtful Accounts Receivable [Roll Forward]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AllowanceForDoubtfulAccountsReceivableRollforward" xlink:label="loc_us-gaap_AllowanceForDoubtfulAccountsReceivableRollforward_50B948DEAFA7EF897B6BE248CAF8CA38" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AllowanceForDoubtfulAccountsReceivableRollforward_50B948DEAFA7EF897B6BE248CAF8CA38" xlink:to="lab_us-gaap_AllowanceForDoubtfulAccountsReceivableRollforward_50B948DEAFA7EF897B6BE248CAF8CA38" xlink:type="arc" />
    <link:label id="lab_us-gaap_AllowanceForDoubtfulAccountsReceivable_331D13F2DA81BD19FA26E248CAF8B3A7_periodStartLabel_en-US" xlink:label="lab_us-gaap_AllowanceForDoubtfulAccountsReceivable_331D13F2DA81BD19FA26E248CAF8B3A7" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel" xlink:type="resource" xml:lang="en-US">Balance at beginning of year</link:label>
    <link:label id="lab_us-gaap_AllowanceForDoubtfulAccountsReceivable_331D13F2DA81BD19FA26E248CAF8B3A7_label_en-US" xlink:label="lab_us-gaap_AllowanceForDoubtfulAccountsReceivable_331D13F2DA81BD19FA26E248CAF8B3A7" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Allowance for Doubtful Accounts Receivable</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AllowanceForDoubtfulAccountsReceivable" xlink:label="loc_us-gaap_AllowanceForDoubtfulAccountsReceivable_331D13F2DA81BD19FA26E248CAF8B3A7" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AllowanceForDoubtfulAccountsReceivable_331D13F2DA81BD19FA26E248CAF8B3A7" xlink:to="lab_us-gaap_AllowanceForDoubtfulAccountsReceivable_331D13F2DA81BD19FA26E248CAF8B3A7" xlink:type="arc" />
    <link:label id="lab_us-gaap_ProvisionForDoubtfulAccounts_585595738CFACCD59F7FE248CAF88610_terseLabel_en-US" xlink:label="lab_us-gaap_ProvisionForDoubtfulAccounts_585595738CFACCD59F7FE248CAF88610" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Provision for doubtful accounts</link:label>
    <link:label id="lab_us-gaap_ProvisionForDoubtfulAccounts_585595738CFACCD59F7FE248CAF88610_label_en-US" xlink:label="lab_us-gaap_ProvisionForDoubtfulAccounts_585595738CFACCD59F7FE248CAF88610" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Provision for Doubtful Accounts</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ProvisionForDoubtfulAccounts" xlink:label="loc_us-gaap_ProvisionForDoubtfulAccounts_585595738CFACCD59F7FE248CAF88610" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ProvisionForDoubtfulAccounts_585595738CFACCD59F7FE248CAF88610" xlink:to="lab_us-gaap_ProvisionForDoubtfulAccounts_585595738CFACCD59F7FE248CAF88610" xlink:type="arc" />
    <link:label id="lab_us-gaap_AllowanceForDoubtfulAccountsReceivableWriteOffs_18746BF988231A57D9CEE248CAF893B9_negatedLabel_en-US" xlink:label="lab_us-gaap_AllowanceForDoubtfulAccountsReceivableWriteOffs_18746BF988231A57D9CEE248CAF893B9" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xml:lang="en-US">Write off of uncollectible accounts</link:label>
    <link:label id="lab_us-gaap_AllowanceForDoubtfulAccountsReceivableWriteOffs_18746BF988231A57D9CEE248CAF893B9_label_en-US" xlink:label="lab_us-gaap_AllowanceForDoubtfulAccountsReceivableWriteOffs_18746BF988231A57D9CEE248CAF893B9" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Allowance for Doubtful Accounts Receivable, Write-offs</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AllowanceForDoubtfulAccountsReceivableWriteOffs" xlink:label="loc_us-gaap_AllowanceForDoubtfulAccountsReceivableWriteOffs_18746BF988231A57D9CEE248CAF893B9" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AllowanceForDoubtfulAccountsReceivableWriteOffs_18746BF988231A57D9CEE248CAF893B9" xlink:to="lab_us-gaap_AllowanceForDoubtfulAccountsReceivableWriteOffs_18746BF988231A57D9CEE248CAF893B9" xlink:type="arc" />
    <link:label id="lab_arnc_AllowanceForDoubtfulAccountsReceivableRecoveriesAdjustments_32AD897C25A4C170CD6EE248CAF82889_terseLabel_en-US" xlink:label="lab_arnc_AllowanceForDoubtfulAccountsReceivableRecoveriesAdjustments_32AD897C25A4C170CD6EE248CAF82889" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Recoveries of prior write-offs</link:label>
    <link:label id="lab_arnc_AllowanceForDoubtfulAccountsReceivableRecoveriesAdjustments_32AD897C25A4C170CD6EE248CAF82889_label_en-US" xlink:label="lab_arnc_AllowanceForDoubtfulAccountsReceivableRecoveriesAdjustments_32AD897C25A4C170CD6EE248CAF82889" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Allowance for Doubtful Accounts Receivable, Recoveries Adjustments</link:label>
    <link:label id="lab_arnc_AllowanceForDoubtfulAccountsReceivableRecoveriesAdjustments_32AD897C25A4C170CD6EE248CAF82889_documentation_en-US" xlink:label="lab_arnc_AllowanceForDoubtfulAccountsReceivableRecoveriesAdjustments_32AD897C25A4C170CD6EE248CAF82889" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Allowance for doubtful accounts receivable, recoveries adjustments.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_AllowanceForDoubtfulAccountsReceivableRecoveriesAdjustments" xlink:label="loc_arnc_AllowanceForDoubtfulAccountsReceivableRecoveriesAdjustments_32AD897C25A4C170CD6EE248CAF82889" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_AllowanceForDoubtfulAccountsReceivableRecoveriesAdjustments_32AD897C25A4C170CD6EE248CAF82889" xlink:to="lab_arnc_AllowanceForDoubtfulAccountsReceivableRecoveriesAdjustments_32AD897C25A4C170CD6EE248CAF82889" xlink:type="arc" />
    <link:label id="lab_arnc_AllowanceForDoubtfulAccountsOtherIncreasesDecreases_B07B69477F2CA4588C2AE248CAF8F9AC_terseLabel_en-US" xlink:label="lab_arnc_AllowanceForDoubtfulAccountsOtherIncreasesDecreases_B07B69477F2CA4588C2AE248CAF8F9AC" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Other</link:label>
    <link:label id="lab_arnc_AllowanceForDoubtfulAccountsOtherIncreasesDecreases_B07B69477F2CA4588C2AE248CAF8F9AC_label_en-US" xlink:label="lab_arnc_AllowanceForDoubtfulAccountsOtherIncreasesDecreases_B07B69477F2CA4588C2AE248CAF8F9AC" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Allowance For Doubtful Accounts, Other Increases (Decreases)</link:label>
    <link:label id="lab_arnc_AllowanceForDoubtfulAccountsOtherIncreasesDecreases_B07B69477F2CA4588C2AE248CAF8F9AC_documentation_en-US" xlink:label="lab_arnc_AllowanceForDoubtfulAccountsOtherIncreasesDecreases_B07B69477F2CA4588C2AE248CAF8F9AC" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Allowance for doubtful accounts other</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_AllowanceForDoubtfulAccountsOtherIncreasesDecreases" xlink:label="loc_arnc_AllowanceForDoubtfulAccountsOtherIncreasesDecreases_B07B69477F2CA4588C2AE248CAF8F9AC" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_AllowanceForDoubtfulAccountsOtherIncreasesDecreases_B07B69477F2CA4588C2AE248CAF8F9AC" xlink:to="lab_arnc_AllowanceForDoubtfulAccountsOtherIncreasesDecreases_B07B69477F2CA4588C2AE248CAF8F9AC" xlink:type="arc" />
    <link:label id="lab_us-gaap_AllowanceForDoubtfulAccountsReceivable_69CA5D588CB4629BB9FCE248CAF84CEE_periodEndLabel_en-US" xlink:label="lab_us-gaap_AllowanceForDoubtfulAccountsReceivable_69CA5D588CB4629BB9FCE248CAF84CEE" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel" xlink:type="resource" xml:lang="en-US">Balance at end of year</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AllowanceForDoubtfulAccountsReceivable" xlink:label="loc_us-gaap_AllowanceForDoubtfulAccountsReceivable_69CA5D588CB4629BB9FCE248CAF84CEE" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AllowanceForDoubtfulAccountsReceivable_69CA5D588CB4629BB9FCE248CAF84CEE" xlink:to="lab_us-gaap_AllowanceForDoubtfulAccountsReceivable_69CA5D588CB4629BB9FCE248CAF84CEE" xlink:type="arc" />
    <link:label id="lab_us-gaap_SegmentReportingDisclosureTextBlock_2DB2CE0B9D8B66ACA3997C36305ED411_terseLabel_en-US" xlink:label="lab_us-gaap_SegmentReportingDisclosureTextBlock_2DB2CE0B9D8B66ACA3997C36305ED411" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Segment and Geographic Area Information</link:label>
    <link:label id="lab_us-gaap_SegmentReportingDisclosureTextBlock_2DB2CE0B9D8B66ACA3997C36305ED411_label_en-US" xlink:label="lab_us-gaap_SegmentReportingDisclosureTextBlock_2DB2CE0B9D8B66ACA3997C36305ED411" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Segment Reporting Disclosure [Text Block]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_SegmentReportingDisclosureTextBlock" xlink:label="loc_us-gaap_SegmentReportingDisclosureTextBlock_2DB2CE0B9D8B66ACA3997C36305ED411" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SegmentReportingDisclosureTextBlock_2DB2CE0B9D8B66ACA3997C36305ED411" xlink:to="lab_us-gaap_SegmentReportingDisclosureTextBlock_2DB2CE0B9D8B66ACA3997C36305ED411" xlink:type="arc" />
    <link:label id="lab_us-gaap_StatementOfStockholdersEquityAbstract_62D05B0685629B6640F607D5A41E6A26_label_en-US" xlink:label="lab_us-gaap_StatementOfStockholdersEquityAbstract_62D05B0685629B6640F607D5A41E6A26" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Statement of Stockholders' Equity [Abstract]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_StatementOfStockholdersEquityAbstract" xlink:label="loc_us-gaap_StatementOfStockholdersEquityAbstract_62D05B0685629B6640F607D5A41E6A26" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_StatementOfStockholdersEquityAbstract_62D05B0685629B6640F607D5A41E6A26" xlink:to="lab_us-gaap_StatementOfStockholdersEquityAbstract_62D05B0685629B6640F607D5A41E6A26" xlink:type="arc" />
    <link:label id="lab_us-gaap_PreferredStockMember_0132FC07A2AB0521A0AC07D5A4202218_terseLabel_en-US" xlink:label="lab_us-gaap_PreferredStockMember_0132FC07A2AB0521A0AC07D5A4202218" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Preferred stock</link:label>
    <link:label id="lab_us-gaap_PreferredStockMember_0132FC07A2AB0521A0AC07D5A4202218_label_en-US" xlink:label="lab_us-gaap_PreferredStockMember_0132FC07A2AB0521A0AC07D5A4202218" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Preferred Stock [Member]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PreferredStockMember" xlink:label="loc_us-gaap_PreferredStockMember_0132FC07A2AB0521A0AC07D5A4202218" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PreferredStockMember_0132FC07A2AB0521A0AC07D5A4202218" xlink:to="lab_us-gaap_PreferredStockMember_0132FC07A2AB0521A0AC07D5A4202218" xlink:type="arc" />
    <link:label id="lab_us-gaap_RetainedEarningsMember_5FAE78BBF7524C17042407D5A4204EBC_terseLabel_en-US" xlink:label="lab_us-gaap_RetainedEarningsMember_5FAE78BBF7524C17042407D5A4204EBC" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Retained earnings (deficit)</link:label>
    <link:label id="lab_us-gaap_RetainedEarningsMember_5FAE78BBF7524C17042407D5A4204EBC_label_en-US" xlink:label="lab_us-gaap_RetainedEarningsMember_5FAE78BBF7524C17042407D5A4204EBC" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Retained Earnings [Member]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RetainedEarningsMember" xlink:label="loc_us-gaap_RetainedEarningsMember_5FAE78BBF7524C17042407D5A4204EBC" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RetainedEarningsMember_5FAE78BBF7524C17042407D5A4204EBC" xlink:to="lab_us-gaap_RetainedEarningsMember_5FAE78BBF7524C17042407D5A4204EBC" xlink:type="arc" />
    <link:label id="lab_us-gaap_AccumulatedOtherComprehensiveIncomeMember_2D8A2BED3C2856FC8C9907D5A421311D_terseLabel_en-US" xlink:label="lab_us-gaap_AccumulatedOtherComprehensiveIncomeMember_2D8A2BED3C2856FC8C9907D5A421311D" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Accumulated Other Comprehensive Loss</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AccumulatedOtherComprehensiveIncomeMember" xlink:label="loc_us-gaap_AccumulatedOtherComprehensiveIncomeMember_2D8A2BED3C2856FC8C9907D5A421311D" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AccumulatedOtherComprehensiveIncomeMember_2D8A2BED3C2856FC8C9907D5A421311D" xlink:to="lab_us-gaap_AccumulatedOtherComprehensiveIncomeMember_2D8A2BED3C2856FC8C9907D5A421311D" xlink:type="arc" />
    <link:label id="lab_us-gaap_OtherComprehensiveIncomeLossNetOfTax_B61F36F850903D19A83F07D5A4242420_terseLabel_en-US" xlink:label="lab_us-gaap_OtherComprehensiveIncomeLossNetOfTax_B61F36F850903D19A83F07D5A4242420" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Other comprehensive (loss) income (K)</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_OtherComprehensiveIncomeLossNetOfTax" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTax_B61F36F850903D19A83F07D5A4242420" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTax_B61F36F850903D19A83F07D5A4242420" xlink:to="lab_us-gaap_OtherComprehensiveIncomeLossNetOfTax_B61F36F850903D19A83F07D5A4242420" xlink:type="arc" />
    <link:label id="lab_us-gaap_DividendsCashAbstract_C9864AD95E3B7BC25C8A07D5A4243CF2_terseLabel_en-US" xlink:label="lab_us-gaap_DividendsCashAbstract_C9864AD95E3B7BC25C8A07D5A4243CF2" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Cash dividends declared:</link:label>
    <link:label id="lab_us-gaap_DividendsCashAbstract_C9864AD95E3B7BC25C8A07D5A4243CF2_label_en-US" xlink:label="lab_us-gaap_DividendsCashAbstract_C9864AD95E3B7BC25C8A07D5A4243CF2" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Dividends, Cash [Abstract]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DividendsCashAbstract" xlink:label="loc_us-gaap_DividendsCashAbstract_C9864AD95E3B7BC25C8A07D5A4243CF2" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DividendsCashAbstract_C9864AD95E3B7BC25C8A07D5A4243CF2" xlink:to="lab_us-gaap_DividendsCashAbstract_C9864AD95E3B7BC25C8A07D5A4243CF2" xlink:type="arc" />
    <link:label id="lab_us-gaap_DividendsPreferredStockCash_B50D62847A35DDD2B9B607D5A424245C_negatedLabel_en-US" xlink:label="lab_us-gaap_DividendsPreferredStockCash_B50D62847A35DDD2B9B607D5A424245C" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xml:lang="en-US">Cash dividends declared, preferred</link:label>
    <link:label id="lab_us-gaap_DividendsPreferredStockCash_B50D62847A35DDD2B9B607D5A424245C_label_en-US" xlink:label="lab_us-gaap_DividendsPreferredStockCash_B50D62847A35DDD2B9B607D5A424245C" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Dividends, Preferred Stock, Cash</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DividendsPreferredStockCash" xlink:label="loc_us-gaap_DividendsPreferredStockCash_B50D62847A35DDD2B9B607D5A424245C" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DividendsPreferredStockCash_B50D62847A35DDD2B9B607D5A424245C" xlink:to="lab_us-gaap_DividendsPreferredStockCash_B50D62847A35DDD2B9B607D5A424245C" xlink:type="arc" />
    <link:label id="lab_us-gaap_DividendsCommonStockCash_176B265C03B8218C99F007D5A4248D0E_negatedLabel_en-US" xlink:label="lab_us-gaap_DividendsCommonStockCash_176B265C03B8218C99F007D5A4248D0E" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xml:lang="en-US">Cash dividends declared, common</link:label>
    <link:label id="lab_us-gaap_DividendsCommonStockCash_176B265C03B8218C99F007D5A4248D0E_label_en-US" xlink:label="lab_us-gaap_DividendsCommonStockCash_176B265C03B8218C99F007D5A4248D0E" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Dividends, Common Stock, Cash</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DividendsCommonStockCash" xlink:label="loc_us-gaap_DividendsCommonStockCash_176B265C03B8218C99F007D5A4248D0E" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DividendsCommonStockCash_176B265C03B8218C99F007D5A4248D0E" xlink:to="lab_us-gaap_DividendsCommonStockCash_176B265C03B8218C99F007D5A4248D0E" xlink:type="arc" />
    <link:label id="lab_us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue_FA10D287E4A33447C8D707D5A4245FFC_terseLabel_en-US" xlink:label="lab_us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue_FA10D287E4A33447C8D707D5A4245FFC" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Stock-based compensation (I)</link:label>
    <link:label id="lab_us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue_FA10D287E4A33447C8D707D5A4245FFC_label_en-US" xlink:label="lab_us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue_FA10D287E4A33447C8D707D5A4245FFC" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Adjustments to Additional Paid in Capital, Share-based Compensation, Requisite Service Period Recognition</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue" xlink:label="loc_us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue_FA10D287E4A33447C8D707D5A4245FFC" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue_FA10D287E4A33447C8D707D5A4245FFC" xlink:to="lab_us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue_FA10D287E4A33447C8D707D5A4245FFC" xlink:type="arc" />
    <link:label id="lab_us-gaap_StockIssuedDuringPeriodValueShareBasedCompensation_427C378717F23425EE3A07D5A425A606_terseLabel_en-US" xlink:label="lab_us-gaap_StockIssuedDuringPeriodValueShareBasedCompensation_427C378717F23425EE3A07D5A425A606" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Common stock issued: compensation plans (I)</link:label>
    <link:label id="lab_us-gaap_StockIssuedDuringPeriodValueShareBasedCompensation_427C378717F23425EE3A07D5A425A606_label_en-US" xlink:label="lab_us-gaap_StockIssuedDuringPeriodValueShareBasedCompensation_427C378717F23425EE3A07D5A425A606" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Stock Issued During Period, Value, Share-based Compensation, Net of Forfeitures</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_StockIssuedDuringPeriodValueShareBasedCompensation" xlink:label="loc_us-gaap_StockIssuedDuringPeriodValueShareBasedCompensation_427C378717F23425EE3A07D5A425A606" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_StockIssuedDuringPeriodValueShareBasedCompensation_427C378717F23425EE3A07D5A425A606" xlink:to="lab_us-gaap_StockIssuedDuringPeriodValueShareBasedCompensation_427C378717F23425EE3A07D5A425A606" xlink:type="arc" />
    <link:label id="lab_us-gaap_TreasuryStockRetiredCostMethodAmount_AF305648261E2A814ED707D5A42538D2_negatedTerseLabel_en-US" xlink:label="lab_us-gaap_TreasuryStockRetiredCostMethodAmount_AF305648261E2A814ED707D5A42538D2" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:type="resource" xml:lang="en-US">Retirement of Treasury stock (I)</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_TreasuryStockRetiredCostMethodAmount" xlink:label="loc_us-gaap_TreasuryStockRetiredCostMethodAmount_AF305648261E2A814ED707D5A42538D2" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_TreasuryStockRetiredCostMethodAmount_AF305648261E2A814ED707D5A42538D2" xlink:to="lab_us-gaap_TreasuryStockRetiredCostMethodAmount_AF305648261E2A814ED707D5A42538D2" xlink:type="arc" />
    <link:label id="lab_arnc_StockIssuedDuringPeriodReverseStockSplitsValue_6C9C0C1BA5DE813AFC5707D5A4255205_negatedTerseLabel_en-US" xlink:label="lab_arnc_StockIssuedDuringPeriodReverseStockSplitsValue_6C9C0C1BA5DE813AFC5707D5A4255205" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:type="resource" xml:lang="en-US">Reverse stock split (I)</link:label>
    <link:label id="lab_arnc_StockIssuedDuringPeriodReverseStockSplitsValue_6C9C0C1BA5DE813AFC5707D5A4255205_label_en-US" xlink:label="lab_arnc_StockIssuedDuringPeriodReverseStockSplitsValue_6C9C0C1BA5DE813AFC5707D5A4255205" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Stock Issued During Period, Reverse Stock Splits, Value</link:label>
    <link:label id="lab_arnc_StockIssuedDuringPeriodReverseStockSplitsValue_6C9C0C1BA5DE813AFC5707D5A4255205_documentation_en-US" xlink:label="lab_arnc_StockIssuedDuringPeriodReverseStockSplitsValue_6C9C0C1BA5DE813AFC5707D5A4255205" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Stock Issued During Period, Reverse Stock Splits, Value</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_StockIssuedDuringPeriodReverseStockSplitsValue" xlink:label="loc_arnc_StockIssuedDuringPeriodReverseStockSplitsValue_6C9C0C1BA5DE813AFC5707D5A4255205" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_StockIssuedDuringPeriodReverseStockSplitsValue_6C9C0C1BA5DE813AFC5707D5A4255205" xlink:to="lab_arnc_StockIssuedDuringPeriodReverseStockSplitsValue_6C9C0C1BA5DE813AFC5707D5A4255205" xlink:type="arc" />
    <link:label id="lab_arnc_MinorityInterestIncreaseDecreaseFromDistributionsToAffiliates_A0AC9A5074D274D4604307D5A425A12E_negatedTerseLabel_en-US" xlink:label="lab_arnc_MinorityInterestIncreaseDecreaseFromDistributionsToAffiliates_A0AC9A5074D274D4604307D5A425A12E" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:type="resource" xml:lang="en-US">Distribution of Alcoa Corporation</link:label>
    <link:label id="lab_arnc_MinorityInterestIncreaseDecreaseFromDistributionsToAffiliates_A0AC9A5074D274D4604307D5A425A12E_label_en-US" xlink:label="lab_arnc_MinorityInterestIncreaseDecreaseFromDistributionsToAffiliates_A0AC9A5074D274D4604307D5A425A12E" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Minority Interest Increase Decrease From Distributions To Affiliates</link:label>
    <link:label id="lab_arnc_MinorityInterestIncreaseDecreaseFromDistributionsToAffiliates_A0AC9A5074D274D4604307D5A425A12E_documentation_en-US" xlink:label="lab_arnc_MinorityInterestIncreaseDecreaseFromDistributionsToAffiliates_A0AC9A5074D274D4604307D5A425A12E" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Minority interest increase decrease from distributions to affiliates.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_MinorityInterestIncreaseDecreaseFromDistributionsToAffiliates" xlink:label="loc_arnc_MinorityInterestIncreaseDecreaseFromDistributionsToAffiliates_A0AC9A5074D274D4604307D5A425A12E" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_MinorityInterestIncreaseDecreaseFromDistributionsToAffiliates_A0AC9A5074D274D4604307D5A425A12E" xlink:to="lab_arnc_MinorityInterestIncreaseDecreaseFromDistributionsToAffiliates_A0AC9A5074D274D4604307D5A425A12E" xlink:type="arc" />
    <link:label id="lab_us-gaap_StockIssuedDuringPeriodValueConversionOfConvertibleSecurities_CB88C5252DA7DDBE093507D5A426A20D_terseLabel_en-US" xlink:label="lab_us-gaap_StockIssuedDuringPeriodValueConversionOfConvertibleSecurities_CB88C5252DA7DDBE093507D5A426A20D" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Conversion of mandatory convertible preferred stock (I)</link:label>
    <link:label id="lab_us-gaap_StockIssuedDuringPeriodValueConversionOfConvertibleSecurities_CB88C5252DA7DDBE093507D5A426A20D_label_en-US" xlink:label="lab_us-gaap_StockIssuedDuringPeriodValueConversionOfConvertibleSecurities_CB88C5252DA7DDBE093507D5A426A20D" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Stock Issued During Period, Value, Conversion of Convertible Securities</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_StockIssuedDuringPeriodValueConversionOfConvertibleSecurities" xlink:label="loc_us-gaap_StockIssuedDuringPeriodValueConversionOfConvertibleSecurities_CB88C5252DA7DDBE093507D5A426A20D" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_StockIssuedDuringPeriodValueConversionOfConvertibleSecurities_CB88C5252DA7DDBE093507D5A426A20D" xlink:to="lab_us-gaap_StockIssuedDuringPeriodValueConversionOfConvertibleSecurities_CB88C5252DA7DDBE093507D5A426A20D" xlink:type="arc" />
    <link:label id="lab_us-gaap_StockIssuedDuringPeriodValueNewIssues_BD0641A782A26448AE2F07D5A4268AB6_terseLabel_en-US" xlink:label="lab_us-gaap_StockIssuedDuringPeriodValueNewIssues_BD0641A782A26448AE2F07D5A4268AB6" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Issuance of common stock (I)</link:label>
    <link:label id="lab_us-gaap_StockIssuedDuringPeriodValueNewIssues_BD0641A782A26448AE2F07D5A4268AB6_label_en-US" xlink:label="lab_us-gaap_StockIssuedDuringPeriodValueNewIssues_BD0641A782A26448AE2F07D5A4268AB6" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Stock Issued During Period, Value, New Issues</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_StockIssuedDuringPeriodValueNewIssues" xlink:label="loc_us-gaap_StockIssuedDuringPeriodValueNewIssues_BD0641A782A26448AE2F07D5A4268AB6" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_StockIssuedDuringPeriodValueNewIssues_BD0641A782A26448AE2F07D5A4268AB6" xlink:to="lab_us-gaap_StockIssuedDuringPeriodValueNewIssues_BD0641A782A26448AE2F07D5A4268AB6" xlink:type="arc" />
    <link:label id="lab_us-gaap_MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders_BCD870078F1755EA47C907D5A426115C_negatedLabel_en-US" xlink:label="lab_us-gaap_MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders_BCD870078F1755EA47C907D5A426115C" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xml:lang="en-US">Distributions</link:label>
    <link:label id="lab_us-gaap_MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders_BCD870078F1755EA47C907D5A426115C_label_en-US" xlink:label="lab_us-gaap_MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders_BCD870078F1755EA47C907D5A426115C" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Noncontrolling Interest, Decrease from Distributions to Noncontrolling Interest Holders</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders" xlink:label="loc_us-gaap_MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders_BCD870078F1755EA47C907D5A426115C" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders_BCD870078F1755EA47C907D5A426115C" xlink:to="lab_us-gaap_MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders_BCD870078F1755EA47C907D5A426115C" xlink:type="arc" />
    <link:label id="lab_arnc_MinorityInterestIncreaseDecreaseFromCapitalContributionFromNoncontrollingInterestHolders_8C824F7335A917AE3C7907D5A426E5DD_terseLabel_en-US" xlink:label="lab_arnc_MinorityInterestIncreaseDecreaseFromCapitalContributionFromNoncontrollingInterestHolders_8C824F7335A917AE3C7907D5A426E5DD" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Contributions</link:label>
    <link:label id="lab_arnc_MinorityInterestIncreaseDecreaseFromCapitalContributionFromNoncontrollingInterestHolders_8C824F7335A917AE3C7907D5A426E5DD_label_en-US" xlink:label="lab_arnc_MinorityInterestIncreaseDecreaseFromCapitalContributionFromNoncontrollingInterestHolders_8C824F7335A917AE3C7907D5A426E5DD" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Minority Interest Increase Decrease From Capital Contribution From Noncontrolling Interest Holders</link:label>
    <link:label id="lab_arnc_MinorityInterestIncreaseDecreaseFromCapitalContributionFromNoncontrollingInterestHolders_8C824F7335A917AE3C7907D5A426E5DD_documentation_en-US" xlink:label="lab_arnc_MinorityInterestIncreaseDecreaseFromCapitalContributionFromNoncontrollingInterestHolders_8C824F7335A917AE3C7907D5A426E5DD" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">The minority interest increase decrease from capital contribution from noncontrolling interest holders.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_MinorityInterestIncreaseDecreaseFromCapitalContributionFromNoncontrollingInterestHolders" xlink:label="loc_arnc_MinorityInterestIncreaseDecreaseFromCapitalContributionFromNoncontrollingInterestHolders_8C824F7335A917AE3C7907D5A426E5DD" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_MinorityInterestIncreaseDecreaseFromCapitalContributionFromNoncontrollingInterestHolders_8C824F7335A917AE3C7907D5A426E5DD" xlink:to="lab_arnc_MinorityInterestIncreaseDecreaseFromCapitalContributionFromNoncontrollingInterestHolders_8C824F7335A917AE3C7907D5A426E5DD" xlink:type="arc" />
    <link:label id="lab_us-gaap_StockholdersEquityOther_23C06DEA4B47CD98A52307D5A4266C3E_negatedLabel_en-US" xlink:label="lab_us-gaap_StockholdersEquityOther_23C06DEA4B47CD98A52307D5A4266C3E" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xml:lang="en-US">Other</link:label>
    <link:label id="lab_us-gaap_StockholdersEquityOther_23C06DEA4B47CD98A52307D5A4266C3E_label_en-US" xlink:label="lab_us-gaap_StockholdersEquityOther_23C06DEA4B47CD98A52307D5A4266C3E" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Stockholders' Equity, Other</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_StockholdersEquityOther" xlink:label="loc_us-gaap_StockholdersEquityOther_23C06DEA4B47CD98A52307D5A4266C3E" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_StockholdersEquityOther_23C06DEA4B47CD98A52307D5A4266C3E" xlink:to="lab_us-gaap_StockholdersEquityOther_23C06DEA4B47CD98A52307D5A4266C3E" xlink:type="arc" />
    <link:label id="lab_arnc_ScheduleOfCommonStockTable_3ED15EA883B2FF14168BE244A94267CD_terseLabel_en-US" xlink:label="lab_arnc_ScheduleOfCommonStockTable_3ED15EA883B2FF14168BE244A94267CD" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Schedule Of Common Stock [Table]</link:label>
    <link:label id="lab_arnc_ScheduleOfCommonStockTable_3ED15EA883B2FF14168BE244A94267CD_label_en-US" xlink:label="lab_arnc_ScheduleOfCommonStockTable_3ED15EA883B2FF14168BE244A94267CD" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Schedule Of Common Stock [Table]</link:label>
    <link:label id="lab_arnc_ScheduleOfCommonStockTable_3ED15EA883B2FF14168BE244A94267CD_documentation_en-US" xlink:label="lab_arnc_ScheduleOfCommonStockTable_3ED15EA883B2FF14168BE244A94267CD" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Schedule Of Common Stock [Table]</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_ScheduleOfCommonStockTable" xlink:label="loc_arnc_ScheduleOfCommonStockTable_3ED15EA883B2FF14168BE244A94267CD" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_ScheduleOfCommonStockTable_3ED15EA883B2FF14168BE244A94267CD" xlink:to="lab_arnc_ScheduleOfCommonStockTable_3ED15EA883B2FF14168BE244A94267CD" xlink:type="arc" />
    <link:label id="lab_srt_RestatementAxis_EA40B634B4F5F7ECED2CE244A9429E1F_terseLabel_en-US" xlink:label="lab_srt_RestatementAxis_EA40B634B4F5F7ECED2CE244A9429E1F" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Restatement [Axis]</link:label>
    <link:label id="lab_srt_RestatementAxis_EA40B634B4F5F7ECED2CE244A9429E1F_label_en-US" xlink:label="lab_srt_RestatementAxis_EA40B634B4F5F7ECED2CE244A9429E1F" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Restatement [Axis]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_RestatementAxis" xlink:label="loc_srt_RestatementAxis_EA40B634B4F5F7ECED2CE244A9429E1F" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_srt_RestatementAxis_EA40B634B4F5F7ECED2CE244A9429E1F" xlink:to="lab_srt_RestatementAxis_EA40B634B4F5F7ECED2CE244A9429E1F" xlink:type="arc" />
    <link:label id="lab_srt_RestatementDomain_E06E882DCFC74E1C3E46E244A94273F5_terseLabel_en-US" xlink:label="lab_srt_RestatementDomain_E06E882DCFC74E1C3E46E244A94273F5" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Restatement [Domain]</link:label>
    <link:label id="lab_srt_RestatementDomain_E06E882DCFC74E1C3E46E244A94273F5_label_en-US" xlink:label="lab_srt_RestatementDomain_E06E882DCFC74E1C3E46E244A94273F5" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Restatement [Domain]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_RestatementDomain" xlink:label="loc_srt_RestatementDomain_E06E882DCFC74E1C3E46E244A94273F5" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_srt_RestatementDomain_E06E882DCFC74E1C3E46E244A94273F5" xlink:to="lab_srt_RestatementDomain_E06E882DCFC74E1C3E46E244A94273F5" xlink:type="arc" />
    <link:label id="lab_srt_RestatementAdjustmentMember_8E936D65E4C92037E422E244A9462256_terseLabel_en-US" xlink:label="lab_srt_RestatementAdjustmentMember_8E936D65E4C92037E422E244A9462256" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Restatement Adjustment</link:label>
    <link:label id="lab_srt_RestatementAdjustmentMember_8E936D65E4C92037E422E244A9462256_label_en-US" xlink:label="lab_srt_RestatementAdjustmentMember_8E936D65E4C92037E422E244A9462256" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Restatement Adjustment [Member]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_RestatementAdjustmentMember" xlink:label="loc_srt_RestatementAdjustmentMember_8E936D65E4C92037E422E244A9462256" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_srt_RestatementAdjustmentMember_8E936D65E4C92037E422E244A9462256" xlink:to="lab_srt_RestatementAdjustmentMember_8E936D65E4C92037E422E244A9462256" xlink:type="arc" />
    <link:label id="lab_us-gaap_FinancialInstrumentAxis_01E2D11E4EAB7976DC81E244A9460A17_terseLabel_en-US" xlink:label="lab_us-gaap_FinancialInstrumentAxis_01E2D11E4EAB7976DC81E244A9460A17" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Financial Instrument [Axis]</link:label>
    <link:label id="lab_us-gaap_FinancialInstrumentAxis_01E2D11E4EAB7976DC81E244A9460A17_label_en-US" xlink:label="lab_us-gaap_FinancialInstrumentAxis_01E2D11E4EAB7976DC81E244A9460A17" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Financial Instrument [Axis]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_FinancialInstrumentAxis" xlink:label="loc_us-gaap_FinancialInstrumentAxis_01E2D11E4EAB7976DC81E244A9460A17" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FinancialInstrumentAxis_01E2D11E4EAB7976DC81E244A9460A17" xlink:to="lab_us-gaap_FinancialInstrumentAxis_01E2D11E4EAB7976DC81E244A9460A17" xlink:type="arc" />
    <link:label id="lab_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_9B80BF319F942D8C6256E244A94675EF_terseLabel_en-US" xlink:label="lab_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_9B80BF319F942D8C6256E244A94675EF" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Financial Instruments [Domain]</link:label>
    <link:label id="lab_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_9B80BF319F942D8C6256E244A94675EF_label_en-US" xlink:label="lab_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_9B80BF319F942D8C6256E244A94675EF" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Financial Instruments [Domain]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain" xlink:label="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_9B80BF319F942D8C6256E244A94675EF" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_9B80BF319F942D8C6256E244A94675EF" xlink:to="lab_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_9B80BF319F942D8C6256E244A94675EF" xlink:type="arc" />
    <link:label id="lab_arnc_ExchangeTradedFixedIncomeAndEquitySecuritiesMember_950ABED4E084FEAAD78EE244A9466CC4_terseLabel_en-US" xlink:label="lab_arnc_ExchangeTradedFixedIncomeAndEquitySecuritiesMember_950ABED4E084FEAAD78EE244A9466CC4" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Exchange Traded Fixed Income and Equity Securities</link:label>
    <link:label id="lab_arnc_ExchangeTradedFixedIncomeAndEquitySecuritiesMember_950ABED4E084FEAAD78EE244A9466CC4_label_en-US" xlink:label="lab_arnc_ExchangeTradedFixedIncomeAndEquitySecuritiesMember_950ABED4E084FEAAD78EE244A9466CC4" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Exchange Traded Fixed Income And Equity Securities [Member]</link:label>
    <link:label id="lab_arnc_ExchangeTradedFixedIncomeAndEquitySecuritiesMember_950ABED4E084FEAAD78EE244A9466CC4_documentation_en-US" xlink:label="lab_arnc_ExchangeTradedFixedIncomeAndEquitySecuritiesMember_950ABED4E084FEAAD78EE244A9466CC4" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Exchange traded fixed income and equity securities.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_ExchangeTradedFixedIncomeAndEquitySecuritiesMember" xlink:label="loc_arnc_ExchangeTradedFixedIncomeAndEquitySecuritiesMember_950ABED4E084FEAAD78EE244A9466CC4" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_ExchangeTradedFixedIncomeAndEquitySecuritiesMember_950ABED4E084FEAAD78EE244A9466CC4" xlink:to="lab_arnc_ExchangeTradedFixedIncomeAndEquitySecuritiesMember_950ABED4E084FEAAD78EE244A9466CC4" xlink:type="arc" />
    <link:label id="lab_arnc_RemmeleMedicalMember_4A42864FBFD36F48D546E244A946F7B3_terseLabel_en-US" xlink:label="lab_arnc_RemmeleMedicalMember_4A42864FBFD36F48D546E244A946F7B3" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Remmele Medical</link:label>
    <link:label id="lab_arnc_RemmeleMedicalMember_4A42864FBFD36F48D546E244A946F7B3_label_en-US" xlink:label="lab_arnc_RemmeleMedicalMember_4A42864FBFD36F48D546E244A946F7B3" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Remmele Medical [Member]</link:label>
    <link:label id="lab_arnc_RemmeleMedicalMember_4A42864FBFD36F48D546E244A946F7B3_documentation_en-US" xlink:label="lab_arnc_RemmeleMedicalMember_4A42864FBFD36F48D546E244A946F7B3" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Remmele Medical [Member]</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_RemmeleMedicalMember" xlink:label="loc_arnc_RemmeleMedicalMember_4A42864FBFD36F48D546E244A946F7B3" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_RemmeleMedicalMember_4A42864FBFD36F48D546E244A946F7B3" xlink:to="lab_arnc_RemmeleMedicalMember_4A42864FBFD36F48D546E244A946F7B3" xlink:type="arc" />
    <link:label id="lab_arnc_ElectricityContractMember_56B257344C4C1E473224E244A946C1DD_terseLabel_en-US" xlink:label="lab_arnc_ElectricityContractMember_56B257344C4C1E473224E244A946C1DD" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Electricity Contract</link:label>
    <link:label id="lab_arnc_ElectricityContractMember_56B257344C4C1E473224E244A946C1DD_label_en-US" xlink:label="lab_arnc_ElectricityContractMember_56B257344C4C1E473224E244A946C1DD" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Electricity Contract [Member]</link:label>
    <link:label id="lab_arnc_ElectricityContractMember_56B257344C4C1E473224E244A946C1DD_documentation_en-US" xlink:label="lab_arnc_ElectricityContractMember_56B257344C4C1E473224E244A946C1DD" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Electricity contract.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_ElectricityContractMember" xlink:label="loc_arnc_ElectricityContractMember_56B257344C4C1E473224E244A946C1DD" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_ElectricityContractMember_56B257344C4C1E473224E244A946C1DD" xlink:to="lab_arnc_ElectricityContractMember_56B257344C4C1E473224E244A946C1DD" xlink:type="arc" />
    <link:label id="lab_arnc_ScheduleOfCommonStockLineItems_D853ADE5F2376ED299D5E244A94A3DBE_terseLabel_en-US" xlink:label="lab_arnc_ScheduleOfCommonStockLineItems_D853ADE5F2376ED299D5E244A94A3DBE" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Schedule Of Common Stock [Line Items]</link:label>
    <link:label id="lab_arnc_ScheduleOfCommonStockLineItems_D853ADE5F2376ED299D5E244A94A3DBE_label_en-US" xlink:label="lab_arnc_ScheduleOfCommonStockLineItems_D853ADE5F2376ED299D5E244A94A3DBE" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Schedule Of Common Stock [Line Items]</link:label>
    <link:label id="lab_arnc_ScheduleOfCommonStockLineItems_D853ADE5F2376ED299D5E244A94A3DBE_documentation_en-US" xlink:label="lab_arnc_ScheduleOfCommonStockLineItems_D853ADE5F2376ED299D5E244A94A3DBE" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Schedule Of Common Stock [Line Items]</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_ScheduleOfCommonStockLineItems" xlink:label="loc_arnc_ScheduleOfCommonStockLineItems_D853ADE5F2376ED299D5E244A94A3DBE" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_ScheduleOfCommonStockLineItems_D853ADE5F2376ED299D5E244A94A3DBE" xlink:to="lab_arnc_ScheduleOfCommonStockLineItems_D853ADE5F2376ED299D5E244A94A3DBE" xlink:type="arc" />
    <link:label id="lab_us-gaap_PaymentsForProceedsFromPreviousAcquisition_EF64ECE97FC1E38EB180E244A94AFE22_terseLabel_en-US" xlink:label="lab_us-gaap_PaymentsForProceedsFromPreviousAcquisition_EF64ECE97FC1E38EB180E244A94AFE22" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Cash payment for a working capital adjustment from prior period acquisition</link:label>
    <link:label id="lab_us-gaap_PaymentsForProceedsFromPreviousAcquisition_EF64ECE97FC1E38EB180E244A94AFE22_label_en-US" xlink:label="lab_us-gaap_PaymentsForProceedsFromPreviousAcquisition_EF64ECE97FC1E38EB180E244A94AFE22" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Payments for (Proceeds from) Previous Acquisition</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PaymentsForProceedsFromPreviousAcquisition" xlink:label="loc_us-gaap_PaymentsForProceedsFromPreviousAcquisition_EF64ECE97FC1E38EB180E244A94AFE22" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PaymentsForProceedsFromPreviousAcquisition_EF64ECE97FC1E38EB180E244A94AFE22" xlink:to="lab_us-gaap_PaymentsForProceedsFromPreviousAcquisition_EF64ECE97FC1E38EB180E244A94AFE22" xlink:type="arc" />
    <link:label id="lab_us-gaap_ProceedsFromSaleMaturityAndCollectionsOfInvestments_B377E4F710140144E8FCE244A94AF1C4_verboseLabel_en-US" xlink:label="lab_us-gaap_ProceedsFromSaleMaturityAndCollectionsOfInvestments_B377E4F710140144E8FCE244A94AF1C4" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Sales of investments</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ProceedsFromSaleMaturityAndCollectionsOfInvestments" xlink:label="loc_us-gaap_ProceedsFromSaleMaturityAndCollectionsOfInvestments_B377E4F710140144E8FCE244A94AF1C4" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ProceedsFromSaleMaturityAndCollectionsOfInvestments_B377E4F710140144E8FCE244A94AF1C4" xlink:to="lab_us-gaap_ProceedsFromSaleMaturityAndCollectionsOfInvestments_B377E4F710140144E8FCE244A94AF1C4" xlink:type="arc" />
    <link:label id="lab_arnc_ProceedsFromSaleOfLifeInsurancePolicies_F9D38E8FDAE893EC7E34E244A94AF9D1_terseLabel_en-US" xlink:label="lab_arnc_ProceedsFromSaleOfLifeInsurancePolicies_F9D38E8FDAE893EC7E34E244A94AF9D1" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Proceeds from sale of company-owned life insurance policies</link:label>
    <link:label id="lab_arnc_ProceedsFromSaleOfLifeInsurancePolicies_F9D38E8FDAE893EC7E34E244A94AF9D1_label_en-US" xlink:label="lab_arnc_ProceedsFromSaleOfLifeInsurancePolicies_F9D38E8FDAE893EC7E34E244A94AF9D1" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Proceeds From Sale Of Life Insurance Policies</link:label>
    <link:label id="lab_arnc_ProceedsFromSaleOfLifeInsurancePolicies_F9D38E8FDAE893EC7E34E244A94AF9D1_documentation_en-US" xlink:label="lab_arnc_ProceedsFromSaleOfLifeInsurancePolicies_F9D38E8FDAE893EC7E34E244A94AF9D1" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Proceeds from sale of life insurance policies.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_ProceedsFromSaleOfLifeInsurancePolicies" xlink:label="loc_arnc_ProceedsFromSaleOfLifeInsurancePolicies_F9D38E8FDAE893EC7E34E244A94AF9D1" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_ProceedsFromSaleOfLifeInsurancePolicies_F9D38E8FDAE893EC7E34E244A94AF9D1" xlink:to="lab_arnc_ProceedsFromSaleOfLifeInsurancePolicies_F9D38E8FDAE893EC7E34E244A94AF9D1" xlink:type="arc" />
    <link:label id="lab_us-gaap_PaymentsForProceedsFromProductiveAssets_5B7F84DA0AA09AE21444E244A94A23D6_negatedTerseLabel_en-US" xlink:label="lab_us-gaap_PaymentsForProceedsFromProductiveAssets_5B7F84DA0AA09AE21444E244A94A23D6" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:type="resource" xml:lang="en-US">Proceeds from divestiture of businesses</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PaymentsForProceedsFromProductiveAssets" xlink:label="loc_us-gaap_PaymentsForProceedsFromProductiveAssets_5B7F84DA0AA09AE21444E244A94A23D6" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PaymentsForProceedsFromProductiveAssets_5B7F84DA0AA09AE21444E244A94A23D6" xlink:to="lab_us-gaap_PaymentsForProceedsFromProductiveAssets_5B7F84DA0AA09AE21444E244A94A23D6" xlink:type="arc" />
    <link:label id="lab_us-gaap_GuaranteeObligationsMaximumExposure_A7061A88B6571428F0B2E244A94A46EF_verboseLabel_en-US" xlink:label="lab_us-gaap_GuaranteeObligationsMaximumExposure_A7061A88B6571428F0B2E244A94A46EF" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Outstanding notes held by Investment banks, including accrued and unpaid interest</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_GuaranteeObligationsMaximumExposure" xlink:label="loc_us-gaap_GuaranteeObligationsMaximumExposure_A7061A88B6571428F0B2E244A94A46EF" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_GuaranteeObligationsMaximumExposure_A7061A88B6571428F0B2E244A94A46EF" xlink:to="lab_us-gaap_GuaranteeObligationsMaximumExposure_A7061A88B6571428F0B2E244A94A46EF" xlink:type="arc" />
    <link:label id="lab_us-gaap_CommonStockSharesOutstanding_15174B5AB4B088759D4CE244A94A1FDE_verboseLabel_en-US" xlink:label="lab_us-gaap_CommonStockSharesOutstanding_15174B5AB4B088759D4CE244A94A1FDE" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Common stock share outstanding (in shares)</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_CommonStockSharesOutstanding" xlink:label="loc_us-gaap_CommonStockSharesOutstanding_15174B5AB4B088759D4CE244A94A1FDE" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CommonStockSharesOutstanding_15174B5AB4B088759D4CE244A94A1FDE" xlink:to="lab_us-gaap_CommonStockSharesOutstanding_15174B5AB4B088759D4CE244A94A1FDE" xlink:type="arc" />
    <link:label id="lab_us-gaap_CommonStockParOrStatedValuePerShare_382601215DEA55150404E244A94A729E_terseLabel_en-US" xlink:label="lab_us-gaap_CommonStockParOrStatedValuePerShare_382601215DEA55150404E244A94A729E" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Common stock par value (usd per share)</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_CommonStockParOrStatedValuePerShare" xlink:label="loc_us-gaap_CommonStockParOrStatedValuePerShare_382601215DEA55150404E244A94A729E" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CommonStockParOrStatedValuePerShare_382601215DEA55150404E244A94A729E" xlink:to="lab_us-gaap_CommonStockParOrStatedValuePerShare_382601215DEA55150404E244A94A729E" xlink:type="arc" />
    <link:label id="lab_arnc_StockIssuedDuringPeriodReverseStockSplitsValue_F2B368DC234689A4D9DCE244A94A4873_terseLabel_en-US" xlink:label="lab_arnc_StockIssuedDuringPeriodReverseStockSplitsValue_F2B368DC234689A4D9DCE244A94A4873" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Impact of reverse stock split</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_StockIssuedDuringPeriodReverseStockSplitsValue" xlink:label="loc_arnc_StockIssuedDuringPeriodReverseStockSplitsValue_F2B368DC234689A4D9DCE244A94A4873" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_StockIssuedDuringPeriodReverseStockSplitsValue_F2B368DC234689A4D9DCE244A94A4873" xlink:to="lab_arnc_StockIssuedDuringPeriodReverseStockSplitsValue_F2B368DC234689A4D9DCE244A94A4873" xlink:type="arc" />
    <link:label id="lab_us-gaap_DefinedBenefitPlanBenefitObligation_C684A4A38F74F6D2C9559F57209DC93B_verboseLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanBenefitObligation_C684A4A38F74F6D2C9559F57209DC93B" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Projected benefit obligation</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DefinedBenefitPlanBenefitObligation" xlink:label="loc_us-gaap_DefinedBenefitPlanBenefitObligation_C684A4A38F74F6D2C9559F57209DC93B" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanBenefitObligation_C684A4A38F74F6D2C9559F57209DC93B" xlink:to="lab_us-gaap_DefinedBenefitPlanBenefitObligation_C684A4A38F74F6D2C9559F57209DC93B" xlink:type="arc" />
    <link:label id="lab_us-gaap_DefinedBenefitPlanAccumulatedBenefitObligation_799D272493E40D9474559F57209DB3C1_terseLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanAccumulatedBenefitObligation_799D272493E40D9474559F57209DB3C1" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Accumulated benefit obligation</link:label>
    <link:label id="lab_us-gaap_DefinedBenefitPlanAccumulatedBenefitObligation_799D272493E40D9474559F57209DB3C1_label_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanAccumulatedBenefitObligation_799D272493E40D9474559F57209DB3C1" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Accumulated Benefit Obligation</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DefinedBenefitPlanAccumulatedBenefitObligation" xlink:label="loc_us-gaap_DefinedBenefitPlanAccumulatedBenefitObligation_799D272493E40D9474559F57209DB3C1" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanAccumulatedBenefitObligation_799D272493E40D9474559F57209DB3C1" xlink:to="lab_us-gaap_DefinedBenefitPlanAccumulatedBenefitObligation_799D272493E40D9474559F57209DB3C1" xlink:type="arc" />
    <link:label id="lab_us-gaap_DefinedBenefitPlanPlansWithBenefitObligationsInExcessOfPlanAssetsAbstract_9D7D28022EF6E093B70A9F57209D235B_terseLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanPlansWithBenefitObligationsInExcessOfPlanAssetsAbstract_9D7D28022EF6E093B70A9F57209D235B" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">The aggregate projected benefit obligation and fair value of plan assets for pension plans with projected benefit obligations in excess of plan assets was as follows:</link:label>
    <link:label id="lab_us-gaap_DefinedBenefitPlanPlansWithBenefitObligationsInExcessOfPlanAssetsAbstract_9D7D28022EF6E093B70A9F57209D235B_label_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanPlansWithBenefitObligationsInExcessOfPlanAssetsAbstract_9D7D28022EF6E093B70A9F57209D235B" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Pension Plan with Project Benefit Obligation in Excess of Plan Assets [Abstract]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DefinedBenefitPlanPlansWithBenefitObligationsInExcessOfPlanAssetsAbstract" xlink:label="loc_us-gaap_DefinedBenefitPlanPlansWithBenefitObligationsInExcessOfPlanAssetsAbstract_9D7D28022EF6E093B70A9F57209D235B" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanPlansWithBenefitObligationsInExcessOfPlanAssetsAbstract_9D7D28022EF6E093B70A9F57209D235B" xlink:to="lab_us-gaap_DefinedBenefitPlanPlansWithBenefitObligationsInExcessOfPlanAssetsAbstract_9D7D28022EF6E093B70A9F57209D235B" xlink:type="arc" />
    <link:label id="lab_us-gaap_DefinedBenefitPlanPensionPlansWithAccumulatedBenefitObligationsInExcessOfPlanAssetsAggregateProjectedBenefitObligation_FCD4EAD91E75D6BEE5689F57209DFD49_terseLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanPensionPlansWithAccumulatedBenefitObligationsInExcessOfPlanAssetsAggregateProjectedBenefitObligation_FCD4EAD91E75D6BEE5689F57209DFD49" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Projected benefit obligation</link:label>
    <link:label id="lab_us-gaap_DefinedBenefitPlanPensionPlansWithAccumulatedBenefitObligationsInExcessOfPlanAssetsAggregateProjectedBenefitObligation_FCD4EAD91E75D6BEE5689F57209DFD49_label_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanPensionPlansWithAccumulatedBenefitObligationsInExcessOfPlanAssetsAggregateProjectedBenefitObligation_FCD4EAD91E75D6BEE5689F57209DFD49" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Pension Plan with Accumulated Benefit Obligation in Excess of Plan Assets, Projected Benefit Obligation</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DefinedBenefitPlanPensionPlansWithAccumulatedBenefitObligationsInExcessOfPlanAssetsAggregateProjectedBenefitObligation" xlink:label="loc_us-gaap_DefinedBenefitPlanPensionPlansWithAccumulatedBenefitObligationsInExcessOfPlanAssetsAggregateProjectedBenefitObligation_FCD4EAD91E75D6BEE5689F57209DFD49" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanPensionPlansWithAccumulatedBenefitObligationsInExcessOfPlanAssetsAggregateProjectedBenefitObligation_FCD4EAD91E75D6BEE5689F57209DFD49" xlink:to="lab_us-gaap_DefinedBenefitPlanPensionPlansWithAccumulatedBenefitObligationsInExcessOfPlanAssetsAggregateProjectedBenefitObligation_FCD4EAD91E75D6BEE5689F57209DFD49" xlink:type="arc" />
    <link:label id="lab_us-gaap_DefinedBenefitPlanPensionPlanWithProjectedBenefitObligationInExcessOfPlanAssetsPlanAssets_A7286A743DF33C27613E9F57209D3A3B_terseLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanPensionPlanWithProjectedBenefitObligationInExcessOfPlanAssetsPlanAssets_A7286A743DF33C27613E9F57209D3A3B" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Fair value of plan assets</link:label>
    <link:label id="lab_us-gaap_DefinedBenefitPlanPensionPlanWithProjectedBenefitObligationInExcessOfPlanAssetsPlanAssets_A7286A743DF33C27613E9F57209D3A3B_label_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanPensionPlanWithProjectedBenefitObligationInExcessOfPlanAssetsPlanAssets_A7286A743DF33C27613E9F57209D3A3B" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Pension Plan with Projected Benefit Obligation in Excess of Plan Assets, Plan Assets</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DefinedBenefitPlanPensionPlanWithProjectedBenefitObligationInExcessOfPlanAssetsPlanAssets" xlink:label="loc_us-gaap_DefinedBenefitPlanPensionPlanWithProjectedBenefitObligationInExcessOfPlanAssetsPlanAssets_A7286A743DF33C27613E9F57209D3A3B" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanPensionPlanWithProjectedBenefitObligationInExcessOfPlanAssetsPlanAssets_A7286A743DF33C27613E9F57209D3A3B" xlink:to="lab_us-gaap_DefinedBenefitPlanPensionPlanWithProjectedBenefitObligationInExcessOfPlanAssetsPlanAssets_A7286A743DF33C27613E9F57209D3A3B" xlink:type="arc" />
    <link:label id="lab_us-gaap_DefinedBenefitPlanPensionPlansWithAccumulatedBenefitObligationsInExcessOfPlanAssetsAbstract_727729AEC9F95E776C4D9F57209D0057_terseLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanPensionPlansWithAccumulatedBenefitObligationsInExcessOfPlanAssetsAbstract_727729AEC9F95E776C4D9F57209D0057" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">The aggregate accumulated benefit obligation and fair value of plan assets for pension plans with accumulated benefit obligations in excess of plan assets was as follows:</link:label>
    <link:label id="lab_us-gaap_DefinedBenefitPlanPensionPlansWithAccumulatedBenefitObligationsInExcessOfPlanAssetsAbstract_727729AEC9F95E776C4D9F57209D0057_label_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanPensionPlansWithAccumulatedBenefitObligationsInExcessOfPlanAssetsAbstract_727729AEC9F95E776C4D9F57209D0057" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Plan with Accumulated Benefit Obligation in Excess of Plan Assets [Abstract]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DefinedBenefitPlanPensionPlansWithAccumulatedBenefitObligationsInExcessOfPlanAssetsAbstract" xlink:label="loc_us-gaap_DefinedBenefitPlanPensionPlansWithAccumulatedBenefitObligationsInExcessOfPlanAssetsAbstract_727729AEC9F95E776C4D9F57209D0057" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanPensionPlansWithAccumulatedBenefitObligationsInExcessOfPlanAssetsAbstract_727729AEC9F95E776C4D9F57209D0057" xlink:to="lab_us-gaap_DefinedBenefitPlanPensionPlansWithAccumulatedBenefitObligationsInExcessOfPlanAssetsAbstract_727729AEC9F95E776C4D9F57209D0057" xlink:type="arc" />
    <link:label id="lab_us-gaap_DefinedBenefitPlanPensionPlansWithAccumulatedBenefitObligationsInExcessOfPlanAssetsAggregateAccumulatedBenefitObligation_6803D4FA70E354A7FD4E9F57209D32A5_terseLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanPensionPlansWithAccumulatedBenefitObligationsInExcessOfPlanAssetsAggregateAccumulatedBenefitObligation_6803D4FA70E354A7FD4E9F57209D32A5" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Accumulated benefit obligation</link:label>
    <link:label id="lab_us-gaap_DefinedBenefitPlanPensionPlansWithAccumulatedBenefitObligationsInExcessOfPlanAssetsAggregateAccumulatedBenefitObligation_6803D4FA70E354A7FD4E9F57209D32A5_label_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanPensionPlansWithAccumulatedBenefitObligationsInExcessOfPlanAssetsAggregateAccumulatedBenefitObligation_6803D4FA70E354A7FD4E9F57209D32A5" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Plan with Accumulated Benefit Obligation in Excess of Plan Assets, Accumulated Benefit Obligation</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DefinedBenefitPlanPensionPlansWithAccumulatedBenefitObligationsInExcessOfPlanAssetsAggregateAccumulatedBenefitObligation" xlink:label="loc_us-gaap_DefinedBenefitPlanPensionPlansWithAccumulatedBenefitObligationsInExcessOfPlanAssetsAggregateAccumulatedBenefitObligation_6803D4FA70E354A7FD4E9F57209D32A5" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanPensionPlansWithAccumulatedBenefitObligationsInExcessOfPlanAssetsAggregateAccumulatedBenefitObligation_6803D4FA70E354A7FD4E9F57209D32A5" xlink:to="lab_us-gaap_DefinedBenefitPlanPensionPlansWithAccumulatedBenefitObligationsInExcessOfPlanAssetsAggregateAccumulatedBenefitObligation_6803D4FA70E354A7FD4E9F57209D32A5" xlink:type="arc" />
    <link:label id="lab_us-gaap_DefinedBenefitPlanPensionPlansWithAccumulatedBenefitObligationsInExcessOfPlanAssetsAggregateFairValueOfPlanAssets_D9C5F715EDA1FA81F6D29F57209D27C2_terseLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanPensionPlansWithAccumulatedBenefitObligationsInExcessOfPlanAssetsAggregateFairValueOfPlanAssets_D9C5F715EDA1FA81F6D29F57209D27C2" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Fair value of plan assets</link:label>
    <link:label id="lab_us-gaap_DefinedBenefitPlanPensionPlansWithAccumulatedBenefitObligationsInExcessOfPlanAssetsAggregateFairValueOfPlanAssets_D9C5F715EDA1FA81F6D29F57209D27C2_label_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanPensionPlansWithAccumulatedBenefitObligationsInExcessOfPlanAssetsAggregateFairValueOfPlanAssets_D9C5F715EDA1FA81F6D29F57209D27C2" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Plan with Accumulated Benefit Obligation in Excess of Plan Assets, Plan Assets</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DefinedBenefitPlanPensionPlansWithAccumulatedBenefitObligationsInExcessOfPlanAssetsAggregateFairValueOfPlanAssets" xlink:label="loc_us-gaap_DefinedBenefitPlanPensionPlansWithAccumulatedBenefitObligationsInExcessOfPlanAssetsAggregateFairValueOfPlanAssets_D9C5F715EDA1FA81F6D29F57209D27C2" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanPensionPlansWithAccumulatedBenefitObligationsInExcessOfPlanAssetsAggregateFairValueOfPlanAssets_D9C5F715EDA1FA81F6D29F57209D27C2" xlink:to="lab_us-gaap_DefinedBenefitPlanPensionPlansWithAccumulatedBenefitObligationsInExcessOfPlanAssetsAggregateFairValueOfPlanAssets_D9C5F715EDA1FA81F6D29F57209D27C2" xlink:type="arc" />
    <link:label id="lab_us-gaap_QuarterlyFinancialInformationTextBlock_868F9A4837EB0EEA3FB0E244A88E493D_terseLabel_en-US" xlink:label="lab_us-gaap_QuarterlyFinancialInformationTextBlock_868F9A4837EB0EEA3FB0E244A88E493D" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Quarterly Data</link:label>
    <link:label id="lab_us-gaap_QuarterlyFinancialInformationTextBlock_868F9A4837EB0EEA3FB0E244A88E493D_label_en-US" xlink:label="lab_us-gaap_QuarterlyFinancialInformationTextBlock_868F9A4837EB0EEA3FB0E244A88E493D" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Quarterly Financial Information [Text Block]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_QuarterlyFinancialInformationTextBlock" xlink:label="loc_us-gaap_QuarterlyFinancialInformationTextBlock_868F9A4837EB0EEA3FB0E244A88E493D" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_QuarterlyFinancialInformationTextBlock_868F9A4837EB0EEA3FB0E244A88E493D" xlink:to="lab_us-gaap_QuarterlyFinancialInformationTextBlock_868F9A4837EB0EEA3FB0E244A88E493D" xlink:type="arc" />
    <link:label id="lab_arnc_FivePointSevenTwoPercentNotesDueTwoThousandNineteenMember_49B216B60F0139F44B28E244A996908C_terseLabel_en-US" xlink:label="lab_arnc_FivePointSevenTwoPercentNotesDueTwoThousandNineteenMember_49B216B60F0139F44B28E244A996908C" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">5.72% Notes, due 2019</link:label>
    <link:label id="lab_arnc_FivePointSevenTwoPercentNotesDueTwoThousandNineteenMember_49B216B60F0139F44B28E244A996908C_label_en-US" xlink:label="lab_arnc_FivePointSevenTwoPercentNotesDueTwoThousandNineteenMember_49B216B60F0139F44B28E244A996908C" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Five Point Seven Two Percent Notes Due Two Thousand Nineteen [Member]</link:label>
    <link:label id="lab_arnc_FivePointSevenTwoPercentNotesDueTwoThousandNineteenMember_49B216B60F0139F44B28E244A996908C_documentation_en-US" xlink:label="lab_arnc_FivePointSevenTwoPercentNotesDueTwoThousandNineteenMember_49B216B60F0139F44B28E244A996908C" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Five point seven two percent notes due two thousand nineteen.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_FivePointSevenTwoPercentNotesDueTwoThousandNineteenMember" xlink:label="loc_arnc_FivePointSevenTwoPercentNotesDueTwoThousandNineteenMember_49B216B60F0139F44B28E244A996908C" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_FivePointSevenTwoPercentNotesDueTwoThousandNineteenMember_49B216B60F0139F44B28E244A996908C" xlink:to="lab_arnc_FivePointSevenTwoPercentNotesDueTwoThousandNineteenMember_49B216B60F0139F44B28E244A996908C" xlink:type="arc" />
    <link:label id="lab_arnc_OnePointSixThreePercentConvertibleNotesDueTwoThousandNineteenMember_ABF30102598C4F27A08EE244A99621C9_terseLabel_en-US" xlink:label="lab_arnc_OnePointSixThreePercentConvertibleNotesDueTwoThousandNineteenMember_ABF30102598C4F27A08EE244A99621C9" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">1.63% Convertible Notes, due 2019</link:label>
    <link:label id="lab_arnc_OnePointSixThreePercentConvertibleNotesDueTwoThousandNineteenMember_ABF30102598C4F27A08EE244A99621C9_label_en-US" xlink:label="lab_arnc_OnePointSixThreePercentConvertibleNotesDueTwoThousandNineteenMember_ABF30102598C4F27A08EE244A99621C9" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">One Point Six Three Percent Convertible Notes Due Two Thousand Nineteen [Member]</link:label>
    <link:label id="lab_arnc_OnePointSixThreePercentConvertibleNotesDueTwoThousandNineteenMember_ABF30102598C4F27A08EE244A99621C9_documentation_en-US" xlink:label="lab_arnc_OnePointSixThreePercentConvertibleNotesDueTwoThousandNineteenMember_ABF30102598C4F27A08EE244A99621C9" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">One Point Six Three Percent Convertible Notes Due Two Thousand Nineteen [Member]</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_OnePointSixThreePercentConvertibleNotesDueTwoThousandNineteenMember" xlink:label="loc_arnc_OnePointSixThreePercentConvertibleNotesDueTwoThousandNineteenMember_ABF30102598C4F27A08EE244A99621C9" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_OnePointSixThreePercentConvertibleNotesDueTwoThousandNineteenMember_ABF30102598C4F27A08EE244A99621C9" xlink:to="lab_arnc_OnePointSixThreePercentConvertibleNotesDueTwoThousandNineteenMember_ABF30102598C4F27A08EE244A99621C9" xlink:type="arc" />
    <link:label id="lab_arnc_SixPointOneFivePercentNotesDueTwoThousandTwentyMember_1E5A58E46E84DD758B78E244A996DCC2_terseLabel_en-US" xlink:label="lab_arnc_SixPointOneFivePercentNotesDueTwoThousandTwentyMember_1E5A58E46E84DD758B78E244A996DCC2" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">6.150% Notes, due 2020</link:label>
    <link:label id="lab_arnc_SixPointOneFivePercentNotesDueTwoThousandTwentyMember_1E5A58E46E84DD758B78E244A996DCC2_label_en-US" xlink:label="lab_arnc_SixPointOneFivePercentNotesDueTwoThousandTwentyMember_1E5A58E46E84DD758B78E244A996DCC2" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Six Point One Five Percent Notes Due Two Thousand Twenty [Member]</link:label>
    <link:label id="lab_arnc_SixPointOneFivePercentNotesDueTwoThousandTwentyMember_1E5A58E46E84DD758B78E244A996DCC2_documentation_en-US" xlink:label="lab_arnc_SixPointOneFivePercentNotesDueTwoThousandTwentyMember_1E5A58E46E84DD758B78E244A996DCC2" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Six point one five percent notes due two thousand twenty.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_SixPointOneFivePercentNotesDueTwoThousandTwentyMember" xlink:label="loc_arnc_SixPointOneFivePercentNotesDueTwoThousandTwentyMember_1E5A58E46E84DD758B78E244A996DCC2" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_SixPointOneFivePercentNotesDueTwoThousandTwentyMember_1E5A58E46E84DD758B78E244A996DCC2" xlink:to="lab_arnc_SixPointOneFivePercentNotesDueTwoThousandTwentyMember_1E5A58E46E84DD758B78E244A996DCC2" xlink:type="arc" />
    <link:label id="lab_arnc_FivePointFourZeroPercentNotesDueTwoThousandTwentyOneMember_7A850CF286879F093F59E244A996EDB5_terseLabel_en-US" xlink:label="lab_arnc_FivePointFourZeroPercentNotesDueTwoThousandTwentyOneMember_7A850CF286879F093F59E244A996EDB5" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">5.40% Notes, due 2021</link:label>
    <link:label id="lab_arnc_FivePointFourZeroPercentNotesDueTwoThousandTwentyOneMember_7A850CF286879F093F59E244A996EDB5_label_en-US" xlink:label="lab_arnc_FivePointFourZeroPercentNotesDueTwoThousandTwentyOneMember_7A850CF286879F093F59E244A996EDB5" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Five Point Four Zero Percent Notes Due Two Thousand Twenty One [Member]</link:label>
    <link:label id="lab_arnc_FivePointFourZeroPercentNotesDueTwoThousandTwentyOneMember_7A850CF286879F093F59E244A996EDB5_documentation_en-US" xlink:label="lab_arnc_FivePointFourZeroPercentNotesDueTwoThousandTwentyOneMember_7A850CF286879F093F59E244A996EDB5" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Five point four zero percent notes due two thousand twenty one.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_FivePointFourZeroPercentNotesDueTwoThousandTwentyOneMember" xlink:label="loc_arnc_FivePointFourZeroPercentNotesDueTwoThousandTwentyOneMember_7A850CF286879F093F59E244A996EDB5" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_FivePointFourZeroPercentNotesDueTwoThousandTwentyOneMember_7A850CF286879F093F59E244A996EDB5" xlink:to="lab_arnc_FivePointFourZeroPercentNotesDueTwoThousandTwentyOneMember_7A850CF286879F093F59E244A996EDB5" xlink:type="arc" />
    <link:label id="lab_arnc_FivePointEightSevenPercentNotesDueTwoThousandTwentyTwoMember_320AEEF4CD31D69201A6E244A996BA2A_terseLabel_en-US" xlink:label="lab_arnc_FivePointEightSevenPercentNotesDueTwoThousandTwentyTwoMember_320AEEF4CD31D69201A6E244A996BA2A" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">5.87% Notes, due 2022</link:label>
    <link:label id="lab_arnc_FivePointEightSevenPercentNotesDueTwoThousandTwentyTwoMember_320AEEF4CD31D69201A6E244A996BA2A_label_en-US" xlink:label="lab_arnc_FivePointEightSevenPercentNotesDueTwoThousandTwentyTwoMember_320AEEF4CD31D69201A6E244A996BA2A" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Five Point Eight Seven Percent Notes Due Two Thousand Twenty Two [Member]</link:label>
    <link:label id="lab_arnc_FivePointEightSevenPercentNotesDueTwoThousandTwentyTwoMember_320AEEF4CD31D69201A6E244A996BA2A_documentation_en-US" xlink:label="lab_arnc_FivePointEightSevenPercentNotesDueTwoThousandTwentyTwoMember_320AEEF4CD31D69201A6E244A996BA2A" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Five point eight seven percent notes due two thousand twenty two.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_FivePointEightSevenPercentNotesDueTwoThousandTwentyTwoMember" xlink:label="loc_arnc_FivePointEightSevenPercentNotesDueTwoThousandTwentyTwoMember_320AEEF4CD31D69201A6E244A996BA2A" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_FivePointEightSevenPercentNotesDueTwoThousandTwentyTwoMember_320AEEF4CD31D69201A6E244A996BA2A" xlink:to="lab_arnc_FivePointEightSevenPercentNotesDueTwoThousandTwentyTwoMember_320AEEF4CD31D69201A6E244A996BA2A" xlink:type="arc" />
    <link:label id="lab_arnc_FivePointOneTwoFivePercentNotesDueTwoThousandTwentyFourMember_1BEE8A5E68A81918AE2DE244A99687FD_terseLabel_en-US" xlink:label="lab_arnc_FivePointOneTwoFivePercentNotesDueTwoThousandTwentyFourMember_1BEE8A5E68A81918AE2DE244A99687FD" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">5.125% Notes, due 2024</link:label>
    <link:label id="lab_arnc_FivePointOneTwoFivePercentNotesDueTwoThousandTwentyFourMember_1BEE8A5E68A81918AE2DE244A99687FD_label_en-US" xlink:label="lab_arnc_FivePointOneTwoFivePercentNotesDueTwoThousandTwentyFourMember_1BEE8A5E68A81918AE2DE244A99687FD" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Five Point One Two Five Percent Notes Due Two Thousand Twenty Four [Member]</link:label>
    <link:label id="lab_arnc_FivePointOneTwoFivePercentNotesDueTwoThousandTwentyFourMember_1BEE8A5E68A81918AE2DE244A99687FD_documentation_en-US" xlink:label="lab_arnc_FivePointOneTwoFivePercentNotesDueTwoThousandTwentyFourMember_1BEE8A5E68A81918AE2DE244A99687FD" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Five Point One Two Five Percent Notes Due Two Thousand Twenty Four [Member]</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_FivePointOneTwoFivePercentNotesDueTwoThousandTwentyFourMember" xlink:label="loc_arnc_FivePointOneTwoFivePercentNotesDueTwoThousandTwentyFourMember_1BEE8A5E68A81918AE2DE244A99687FD" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_FivePointOneTwoFivePercentNotesDueTwoThousandTwentyFourMember_1BEE8A5E68A81918AE2DE244A99687FD" xlink:to="lab_arnc_FivePointOneTwoFivePercentNotesDueTwoThousandTwentyFourMember_1BEE8A5E68A81918AE2DE244A99687FD" xlink:type="arc" />
    <link:label id="lab_arnc_FivePointNinePercentNotesDueTwoThousandTwentySevenMember_65986E13D576EC5FF7DAE244A9961700_terseLabel_en-US" xlink:label="lab_arnc_FivePointNinePercentNotesDueTwoThousandTwentySevenMember_65986E13D576EC5FF7DAE244A9961700" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">5.90% Notes, due 2027</link:label>
    <link:label id="lab_arnc_FivePointNinePercentNotesDueTwoThousandTwentySevenMember_65986E13D576EC5FF7DAE244A9961700_label_en-US" xlink:label="lab_arnc_FivePointNinePercentNotesDueTwoThousandTwentySevenMember_65986E13D576EC5FF7DAE244A9961700" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Five Point Nine Percent Notes Due Two Thousand Twenty Seven [Member]</link:label>
    <link:label id="lab_arnc_FivePointNinePercentNotesDueTwoThousandTwentySevenMember_65986E13D576EC5FF7DAE244A9961700_documentation_en-US" xlink:label="lab_arnc_FivePointNinePercentNotesDueTwoThousandTwentySevenMember_65986E13D576EC5FF7DAE244A9961700" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Five point nine percent notes due two thousand twenty seven.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_FivePointNinePercentNotesDueTwoThousandTwentySevenMember" xlink:label="loc_arnc_FivePointNinePercentNotesDueTwoThousandTwentySevenMember_65986E13D576EC5FF7DAE244A9961700" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_FivePointNinePercentNotesDueTwoThousandTwentySevenMember_65986E13D576EC5FF7DAE244A9961700" xlink:to="lab_arnc_FivePointNinePercentNotesDueTwoThousandTwentySevenMember_65986E13D576EC5FF7DAE244A9961700" xlink:type="arc" />
    <link:label id="lab_arnc_SixPointSevenFivePercentBondsDueTwoThousandTwentyEightMember_3EDC69995E9FD7238803E244A9961B21_terseLabel_en-US" xlink:label="lab_arnc_SixPointSevenFivePercentBondsDueTwoThousandTwentyEightMember_3EDC69995E9FD7238803E244A9961B21" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">6.75% Bonds, due 2028</link:label>
    <link:label id="lab_arnc_SixPointSevenFivePercentBondsDueTwoThousandTwentyEightMember_3EDC69995E9FD7238803E244A9961B21_label_en-US" xlink:label="lab_arnc_SixPointSevenFivePercentBondsDueTwoThousandTwentyEightMember_3EDC69995E9FD7238803E244A9961B21" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Six Point Seven Five Percent Bonds Due Two Thousand Twenty Eight [Member]</link:label>
    <link:label id="lab_arnc_SixPointSevenFivePercentBondsDueTwoThousandTwentyEightMember_3EDC69995E9FD7238803E244A9961B21_documentation_en-US" xlink:label="lab_arnc_SixPointSevenFivePercentBondsDueTwoThousandTwentyEightMember_3EDC69995E9FD7238803E244A9961B21" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Six point seven five percent bonds due two thousand twenty eight.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_SixPointSevenFivePercentBondsDueTwoThousandTwentyEightMember" xlink:label="loc_arnc_SixPointSevenFivePercentBondsDueTwoThousandTwentyEightMember_3EDC69995E9FD7238803E244A9961B21" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_SixPointSevenFivePercentBondsDueTwoThousandTwentyEightMember_3EDC69995E9FD7238803E244A9961B21" xlink:to="lab_arnc_SixPointSevenFivePercentBondsDueTwoThousandTwentyEightMember_3EDC69995E9FD7238803E244A9961B21" xlink:type="arc" />
    <link:label id="lab_arnc_FivePointNineFivePercentNotesDueTwoThousandThirtySevenMember_8C3880790F40211BCFE6E244A9962A59_terseLabel_en-US" xlink:label="lab_arnc_FivePointNineFivePercentNotesDueTwoThousandThirtySevenMember_8C3880790F40211BCFE6E244A9962A59" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">5.95% Notes due 2037</link:label>
    <link:label id="lab_arnc_FivePointNineFivePercentNotesDueTwoThousandThirtySevenMember_8C3880790F40211BCFE6E244A9962A59_label_en-US" xlink:label="lab_arnc_FivePointNineFivePercentNotesDueTwoThousandThirtySevenMember_8C3880790F40211BCFE6E244A9962A59" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Five Point Nine Five Percent Notes Due Two Thousand Thirty Seven [Member]</link:label>
    <link:label id="lab_arnc_FivePointNineFivePercentNotesDueTwoThousandThirtySevenMember_8C3880790F40211BCFE6E244A9962A59_documentation_en-US" xlink:label="lab_arnc_FivePointNineFivePercentNotesDueTwoThousandThirtySevenMember_8C3880790F40211BCFE6E244A9962A59" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Five point nine five percent notes due two thousand thirty seven.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_FivePointNineFivePercentNotesDueTwoThousandThirtySevenMember" xlink:label="loc_arnc_FivePointNineFivePercentNotesDueTwoThousandThirtySevenMember_8C3880790F40211BCFE6E244A9962A59" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_FivePointNineFivePercentNotesDueTwoThousandThirtySevenMember_8C3880790F40211BCFE6E244A9962A59" xlink:to="lab_arnc_FivePointNineFivePercentNotesDueTwoThousandThirtySevenMember_8C3880790F40211BCFE6E244A9962A59" xlink:type="arc" />
    <link:label id="lab_arnc_IowaAuthorityLoanMember_ED228B42E89EF2CA0F73E244A996D421_terseLabel_en-US" xlink:label="lab_arnc_IowaAuthorityLoanMember_ED228B42E89EF2CA0F73E244A996D421" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Iowa Finance Authority Loan, due 2042 (4.75%)</link:label>
    <link:label id="lab_arnc_IowaAuthorityLoanMember_ED228B42E89EF2CA0F73E244A996D421_label_en-US" xlink:label="lab_arnc_IowaAuthorityLoanMember_ED228B42E89EF2CA0F73E244A996D421" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Iowa Authority Loan [Member]</link:label>
    <link:label id="lab_arnc_IowaAuthorityLoanMember_ED228B42E89EF2CA0F73E244A996D421_documentation_en-US" xlink:label="lab_arnc_IowaAuthorityLoanMember_ED228B42E89EF2CA0F73E244A996D421" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Iowa Authority Loan [Member]</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_IowaAuthorityLoanMember" xlink:label="loc_arnc_IowaAuthorityLoanMember_ED228B42E89EF2CA0F73E244A996D421" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_IowaAuthorityLoanMember_ED228B42E89EF2CA0F73E244A996D421" xlink:to="lab_arnc_IowaAuthorityLoanMember_ED228B42E89EF2CA0F73E244A996D421" xlink:type="arc" />
    <link:label id="lab_arnc_OtherMember_3E7F422B0E6E7368EE21E244A996B473_terseLabel_en-US" xlink:label="lab_arnc_OtherMember_3E7F422B0E6E7368EE21E244A996B473" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Other</link:label>
    <link:label id="lab_arnc_OtherMember_3E7F422B0E6E7368EE21E244A996B473_label_en-US" xlink:label="lab_arnc_OtherMember_3E7F422B0E6E7368EE21E244A996B473" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Other [Member]</link:label>
    <link:label id="lab_arnc_OtherMember_3E7F422B0E6E7368EE21E244A996B473_documentation_en-US" xlink:label="lab_arnc_OtherMember_3E7F422B0E6E7368EE21E244A996B473" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Other [Member]</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_OtherMember" xlink:label="loc_arnc_OtherMember_3E7F422B0E6E7368EE21E244A996B473" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_OtherMember_3E7F422B0E6E7368EE21E244A996B473" xlink:to="lab_arnc_OtherMember_3E7F422B0E6E7368EE21E244A996B473" xlink:type="arc" />
    <link:label id="lab_us-gaap_LongTermDebt_D036087E6137CA4ECEF3E244A996971E_totalLabel_en-US" xlink:label="lab_us-gaap_LongTermDebt_D036087E6137CA4ECEF3E244A996971E" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Long-term debt</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_LongTermDebt" xlink:label="loc_us-gaap_LongTermDebt_D036087E6137CA4ECEF3E244A996971E" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LongTermDebt_D036087E6137CA4ECEF3E244A996971E" xlink:to="lab_us-gaap_LongTermDebt_D036087E6137CA4ECEF3E244A996971E" xlink:type="arc" />
    <link:label id="lab_us-gaap_OtherLongTermDebt_24B5895BF73A6368EF4AE244A996547E_negatedLabel_en-US" xlink:label="lab_us-gaap_OtherLongTermDebt_24B5895BF73A6368EF4AE244A996547E" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xml:lang="en-US">Other</link:label>
    <link:label id="lab_us-gaap_OtherLongTermDebt_24B5895BF73A6368EF4AE244A996547E_label_en-US" xlink:label="lab_us-gaap_OtherLongTermDebt_24B5895BF73A6368EF4AE244A996547E" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Other Long-term Debt</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_OtherLongTermDebt" xlink:label="loc_us-gaap_OtherLongTermDebt_24B5895BF73A6368EF4AE244A996547E" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OtherLongTermDebt_24B5895BF73A6368EF4AE244A996547E" xlink:to="lab_us-gaap_OtherLongTermDebt_24B5895BF73A6368EF4AE244A996547E" xlink:type="arc" />
    <link:label id="lab_us-gaap_LongTermDebtCurrent_63B9F5195CE0F2FEAFF9E244A9960773_terseLabel_en-US" xlink:label="lab_us-gaap_LongTermDebtCurrent_63B9F5195CE0F2FEAFF9E244A9960773" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Less: amount due within one year</link:label>
    <link:label id="lab_us-gaap_LongTermDebtCurrent_63B9F5195CE0F2FEAFF9E244A9960773_label_en-US" xlink:label="lab_us-gaap_LongTermDebtCurrent_63B9F5195CE0F2FEAFF9E244A9960773" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Long-term Debt, Current Maturities</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_LongTermDebtCurrent" xlink:label="loc_us-gaap_LongTermDebtCurrent_63B9F5195CE0F2FEAFF9E244A9960773" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LongTermDebtCurrent_63B9F5195CE0F2FEAFF9E244A9960773" xlink:to="lab_us-gaap_LongTermDebtCurrent_63B9F5195CE0F2FEAFF9E244A9960773" xlink:type="arc" />
    <link:label id="lab_us-gaap_LongTermDebtNoncurrent_2362CC5B513A86DD2C76E244A9963314_terseLabel_en-US" xlink:label="lab_us-gaap_LongTermDebtNoncurrent_2362CC5B513A86DD2C76E244A9963314" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Long-term debt, excluding amount due within one year</link:label>
    <link:label id="lab_us-gaap_LongTermDebtNoncurrent_2362CC5B513A86DD2C76E244A9963314_label_en-US" xlink:label="lab_us-gaap_LongTermDebtNoncurrent_2362CC5B513A86DD2C76E244A9963314" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Long-term Debt, Excluding Current Maturities</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_LongTermDebtNoncurrent" xlink:label="loc_us-gaap_LongTermDebtNoncurrent_2362CC5B513A86DD2C76E244A9963314" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LongTermDebtNoncurrent_2362CC5B513A86DD2C76E244A9963314" xlink:to="lab_us-gaap_LongTermDebtNoncurrent_2362CC5B513A86DD2C76E244A9963314" xlink:type="arc" />
    <link:label id="lab_arnc_SixPointFivePercentBondsDueTwoThousandEighteenMember_E65ED14EF502D35CC65A011AD191A0BA_terseLabel_en-US" xlink:label="lab_arnc_SixPointFivePercentBondsDueTwoThousandEighteenMember_E65ED14EF502D35CC65A011AD191A0BA" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">6.50% Bonds, due 2018</link:label>
    <link:label id="lab_arnc_SixPointFivePercentBondsDueTwoThousandEighteenMember_E65ED14EF502D35CC65A011AD191A0BA_label_en-US" xlink:label="lab_arnc_SixPointFivePercentBondsDueTwoThousandEighteenMember_E65ED14EF502D35CC65A011AD191A0BA" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Six Point Five Percent Bonds Due Two Thousand Eighteen [Member]</link:label>
    <link:label id="lab_arnc_SixPointFivePercentBondsDueTwoThousandEighteenMember_E65ED14EF502D35CC65A011AD191A0BA_documentation_en-US" xlink:label="lab_arnc_SixPointFivePercentBondsDueTwoThousandEighteenMember_E65ED14EF502D35CC65A011AD191A0BA" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Six point five percent bonds due two thousand eighteen.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_SixPointFivePercentBondsDueTwoThousandEighteenMember" xlink:label="loc_arnc_SixPointFivePercentBondsDueTwoThousandEighteenMember_E65ED14EF502D35CC65A011AD191A0BA" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_SixPointFivePercentBondsDueTwoThousandEighteenMember_E65ED14EF502D35CC65A011AD191A0BA" xlink:to="lab_arnc_SixPointFivePercentBondsDueTwoThousandEighteenMember_E65ED14EF502D35CC65A011AD191A0BA" xlink:type="arc" />
    <link:label id="lab_arnc_SixPointSevenFivePercentNotesDueTwoThousandEighteenMember_AD9007B7330CDE4CF843011AD192F72C_terseLabel_en-US" xlink:label="lab_arnc_SixPointSevenFivePercentNotesDueTwoThousandEighteenMember_AD9007B7330CDE4CF843011AD192F72C" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">6.75% Notes, due 2018</link:label>
    <link:label id="lab_arnc_SixPointSevenFivePercentNotesDueTwoThousandEighteenMember_AD9007B7330CDE4CF843011AD192F72C_label_en-US" xlink:label="lab_arnc_SixPointSevenFivePercentNotesDueTwoThousandEighteenMember_AD9007B7330CDE4CF843011AD192F72C" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Six Point Seven Five Percent Notes Due Two Thousand Eighteen [Member]</link:label>
    <link:label id="lab_arnc_SixPointSevenFivePercentNotesDueTwoThousandEighteenMember_AD9007B7330CDE4CF843011AD192F72C_documentation_en-US" xlink:label="lab_arnc_SixPointSevenFivePercentNotesDueTwoThousandEighteenMember_AD9007B7330CDE4CF843011AD192F72C" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Six point seven five percent notes due two thousand eighteen.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_SixPointSevenFivePercentNotesDueTwoThousandEighteenMember" xlink:label="loc_arnc_SixPointSevenFivePercentNotesDueTwoThousandEighteenMember_AD9007B7330CDE4CF843011AD192F72C" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_SixPointSevenFivePercentNotesDueTwoThousandEighteenMember_AD9007B7330CDE4CF843011AD192F72C" xlink:to="lab_arnc_SixPointSevenFivePercentNotesDueTwoThousandEighteenMember_AD9007B7330CDE4CF843011AD192F72C" xlink:type="arc" />
    <link:label id="lab_us-gaap_InterestRateSwapMember_9152372686BABE935678011AD199A9B3_terseLabel_en-US" xlink:label="lab_us-gaap_InterestRateSwapMember_9152372686BABE935678011AD199A9B3" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Interest Rate Swap</link:label>
    <link:label id="lab_us-gaap_InterestRateSwapMember_9152372686BABE935678011AD199A9B3_label_en-US" xlink:label="lab_us-gaap_InterestRateSwapMember_9152372686BABE935678011AD199A9B3" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Interest Rate Swap [Member]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_InterestRateSwapMember" xlink:label="loc_us-gaap_InterestRateSwapMember_9152372686BABE935678011AD199A9B3" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_InterestRateSwapMember_9152372686BABE935678011AD199A9B3" xlink:to="lab_us-gaap_InterestRateSwapMember_9152372686BABE935678011AD199A9B3" xlink:type="arc" />
    <link:label id="lab_us-gaap_DebtInstrumentInterestRateStatedPercentage_BA90797B3FEAC88B7D61011AD199FC5B_terseLabel_en-US" xlink:label="lab_us-gaap_DebtInstrumentInterestRateStatedPercentage_BA90797B3FEAC88B7D61011AD199FC5B" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Convertible notes, interest rate percentage</link:label>
    <link:label id="lab_us-gaap_DebtInstrumentInterestRateStatedPercentage_BA90797B3FEAC88B7D61011AD199FC5B_label_en-US" xlink:label="lab_us-gaap_DebtInstrumentInterestRateStatedPercentage_BA90797B3FEAC88B7D61011AD199FC5B" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Debt Instrument, Interest Rate, Stated Percentage</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DebtInstrumentInterestRateStatedPercentage" xlink:label="loc_us-gaap_DebtInstrumentInterestRateStatedPercentage_BA90797B3FEAC88B7D61011AD199FC5B" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DebtInstrumentInterestRateStatedPercentage_BA90797B3FEAC88B7D61011AD199FC5B" xlink:to="lab_us-gaap_DebtInstrumentInterestRateStatedPercentage_BA90797B3FEAC88B7D61011AD199FC5B" xlink:type="arc" />
    <link:label id="lab_arnc_DebtInstrumentRedemptionAmount_059B595A730DBFF41380011AD19A4161_terseLabel_en-US" xlink:label="lab_arnc_DebtInstrumentRedemptionAmount_059B595A730DBFF41380011AD19A4161" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Debt instrument redemption amount</link:label>
    <link:label id="lab_arnc_DebtInstrumentRedemptionAmount_059B595A730DBFF41380011AD19A4161_label_en-US" xlink:label="lab_arnc_DebtInstrumentRedemptionAmount_059B595A730DBFF41380011AD19A4161" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Debt Instrument Redemption Amount</link:label>
    <link:label id="lab_arnc_DebtInstrumentRedemptionAmount_059B595A730DBFF41380011AD19A4161_documentation_en-US" xlink:label="lab_arnc_DebtInstrumentRedemptionAmount_059B595A730DBFF41380011AD19A4161" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Debt instrument redemption amount.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_DebtInstrumentRedemptionAmount" xlink:label="loc_arnc_DebtInstrumentRedemptionAmount_059B595A730DBFF41380011AD19A4161" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_DebtInstrumentRedemptionAmount_059B595A730DBFF41380011AD19A4161" xlink:to="lab_arnc_DebtInstrumentRedemptionAmount_059B595A730DBFF41380011AD19A4161" xlink:type="arc" />
    <link:label id="lab_us-gaap_GainsLossesOnExtinguishmentOfDebt_04EE44F7EADB38DF5483011AD19A1133_negatedLabel_en-US" xlink:label="lab_us-gaap_GainsLossesOnExtinguishmentOfDebt_04EE44F7EADB38DF5483011AD19A1133" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xml:lang="en-US">Loss on extinguishment of debt</link:label>
    <link:label id="lab_us-gaap_GainsLossesOnExtinguishmentOfDebt_04EE44F7EADB38DF5483011AD19A1133_label_en-US" xlink:label="lab_us-gaap_GainsLossesOnExtinguishmentOfDebt_04EE44F7EADB38DF5483011AD19A1133" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Gain (Loss) on Extinguishment of Debt</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_GainsLossesOnExtinguishmentOfDebt" xlink:label="loc_us-gaap_GainsLossesOnExtinguishmentOfDebt_04EE44F7EADB38DF5483011AD19A1133" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_GainsLossesOnExtinguishmentOfDebt_04EE44F7EADB38DF5483011AD19A1133" xlink:to="lab_us-gaap_GainsLossesOnExtinguishmentOfDebt_04EE44F7EADB38DF5483011AD19A1133" xlink:type="arc" />
    <link:label id="lab_arnc_NumberOfCashTenderOffers_B752768142FF56843D04011AD19AB700_terseLabel_en-US" xlink:label="lab_arnc_NumberOfCashTenderOffers_B752768142FF56843D04011AD19AB700" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Number of cash tender offers</link:label>
    <link:label id="lab_arnc_NumberOfCashTenderOffers_B752768142FF56843D04011AD19AB700_label_en-US" xlink:label="lab_arnc_NumberOfCashTenderOffers_B752768142FF56843D04011AD19AB700" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Number Of Cash Tender Offers</link:label>
    <link:label id="lab_arnc_NumberOfCashTenderOffers_B752768142FF56843D04011AD19AB700_documentation_en-US" xlink:label="lab_arnc_NumberOfCashTenderOffers_B752768142FF56843D04011AD19AB700" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Number Of Cash Tender Offers</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_NumberOfCashTenderOffers" xlink:label="loc_arnc_NumberOfCashTenderOffers_B752768142FF56843D04011AD19AB700" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_NumberOfCashTenderOffers_B752768142FF56843D04011AD19AB700" xlink:to="lab_arnc_NumberOfCashTenderOffers_B752768142FF56843D04011AD19AB700" xlink:type="arc" />
    <link:label id="lab_us-gaap_RepaymentsOfDebt_468F59EDDD0C4177C118011AD19A7189_terseLabel_en-US" xlink:label="lab_us-gaap_RepaymentsOfDebt_468F59EDDD0C4177C118011AD19A7189" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Cash paid to holders of debt instrument, net</link:label>
    <link:label id="lab_us-gaap_RepaymentsOfDebt_468F59EDDD0C4177C118011AD19A7189_label_en-US" xlink:label="lab_us-gaap_RepaymentsOfDebt_468F59EDDD0C4177C118011AD19A7189" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Repayments of Debt</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RepaymentsOfDebt" xlink:label="loc_us-gaap_RepaymentsOfDebt_468F59EDDD0C4177C118011AD19A7189" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RepaymentsOfDebt_468F59EDDD0C4177C118011AD19A7189" xlink:to="lab_us-gaap_RepaymentsOfDebt_468F59EDDD0C4177C118011AD19A7189" xlink:type="arc" />
    <link:label id="lab_us-gaap_DebtInstrumentRepurchaseAmount_75D585328260634B9042011AD19BF0BB_terseLabel_en-US" xlink:label="lab_us-gaap_DebtInstrumentRepurchaseAmount_75D585328260634B9042011AD19BF0BB" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Debt instrument, repurchase amount</link:label>
    <link:label id="lab_us-gaap_DebtInstrumentRepurchaseAmount_75D585328260634B9042011AD19BF0BB_label_en-US" xlink:label="lab_us-gaap_DebtInstrumentRepurchaseAmount_75D585328260634B9042011AD19BF0BB" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Debt Instrument, Repurchase Amount</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DebtInstrumentRepurchaseAmount" xlink:label="loc_us-gaap_DebtInstrumentRepurchaseAmount_75D585328260634B9042011AD19BF0BB" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DebtInstrumentRepurchaseAmount_75D585328260634B9042011AD19BF0BB" xlink:to="lab_us-gaap_DebtInstrumentRepurchaseAmount_75D585328260634B9042011AD19BF0BB" xlink:type="arc" />
    <link:label id="lab_us-gaap_InterestExpenseDebt_9E464845527976A96A24011AD19BE831_terseLabel_en-US" xlink:label="lab_us-gaap_InterestExpenseDebt_9E464845527976A96A24011AD19BE831" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Interest charge related to early redemption of notes</link:label>
    <link:label id="lab_us-gaap_InterestExpenseDebt_9E464845527976A96A24011AD19BE831_label_en-US" xlink:label="lab_us-gaap_InterestExpenseDebt_9E464845527976A96A24011AD19BE831" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Interest Expense, Debt</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_InterestExpenseDebt" xlink:label="loc_us-gaap_InterestExpenseDebt_9E464845527976A96A24011AD19BE831" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_InterestExpenseDebt_9E464845527976A96A24011AD19BE831" xlink:to="lab_us-gaap_InterestExpenseDebt_9E464845527976A96A24011AD19BE831" xlink:type="arc" />
    <link:label id="lab_us-gaap_InterestPaid_65CCDA54BF477BE3F7A5011AD19B23CA_terseLabel_en-US" xlink:label="lab_us-gaap_InterestPaid_65CCDA54BF477BE3F7A5011AD19B23CA" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Interest paid</link:label>
    <link:label id="lab_us-gaap_InterestPaid_65CCDA54BF477BE3F7A5011AD19B23CA_label_en-US" xlink:label="lab_us-gaap_InterestPaid_65CCDA54BF477BE3F7A5011AD19B23CA" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Interest Paid, Including Capitalized Interest, Operating and Investing Activities</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_InterestPaid" xlink:label="loc_us-gaap_InterestPaid_65CCDA54BF477BE3F7A5011AD19B23CA" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_InterestPaid_65CCDA54BF477BE3F7A5011AD19B23CA" xlink:to="lab_us-gaap_InterestPaid_65CCDA54BF477BE3F7A5011AD19B23CA" xlink:type="arc" />
    <link:label id="lab_us-gaap_ProceedsFromInterestReceived_E0D2472DA5DF95B4D0D8011AD19B0C59_terseLabel_en-US" xlink:label="lab_us-gaap_ProceedsFromInterestReceived_E0D2472DA5DF95B4D0D8011AD19B0C59" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Proceeds from interest received</link:label>
    <link:label id="lab_us-gaap_ProceedsFromInterestReceived_E0D2472DA5DF95B4D0D8011AD19B0C59_label_en-US" xlink:label="lab_us-gaap_ProceedsFromInterestReceived_E0D2472DA5DF95B4D0D8011AD19B0C59" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Proceeds from Interest Received</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ProceedsFromInterestReceived" xlink:label="loc_us-gaap_ProceedsFromInterestReceived_E0D2472DA5DF95B4D0D8011AD19B0C59" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ProceedsFromInterestReceived_E0D2472DA5DF95B4D0D8011AD19B0C59" xlink:to="lab_us-gaap_ProceedsFromInterestReceived_E0D2472DA5DF95B4D0D8011AD19B0C59" xlink:type="arc" />
    <link:label id="lab_us-gaap_LegalFees_C8A835625C65246255F5011AD19B05AD_terseLabel_en-US" xlink:label="lab_us-gaap_LegalFees_C8A835625C65246255F5011AD19B05AD" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Legal fees</link:label>
    <link:label id="lab_us-gaap_LegalFees_C8A835625C65246255F5011AD19B05AD_label_en-US" xlink:label="lab_us-gaap_LegalFees_C8A835625C65246255F5011AD19B05AD" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Legal Fees</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_LegalFees" xlink:label="loc_us-gaap_LegalFees_C8A835625C65246255F5011AD19B05AD" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LegalFees_C8A835625C65246255F5011AD19B05AD" xlink:to="lab_us-gaap_LegalFees_C8A835625C65246255F5011AD19B05AD" xlink:type="arc" />
    <link:label id="lab_us-gaap_InterestExpense_6A4D44CD7488F2B62E11011AD19C31DF_verboseLabel_en-US" xlink:label="lab_us-gaap_InterestExpense_6A4D44CD7488F2B62E11011AD19C31DF" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Interest expense</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_InterestExpense" xlink:label="loc_us-gaap_InterestExpense_6A4D44CD7488F2B62E11011AD19C31DF" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_InterestExpense_6A4D44CD7488F2B62E11011AD19C31DF" xlink:to="lab_us-gaap_InterestExpense_6A4D44CD7488F2B62E11011AD19C31DF" xlink:type="arc" />
    <link:label id="lab_arnc_ShutdownAndCurtailmentActionsMember_1D12E7086661C1D66B6696B482B6ADA0_terseLabel_en-US" xlink:label="lab_arnc_ShutdownAndCurtailmentActionsMember_1D12E7086661C1D66B6696B482B6ADA0" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Shutdown and Curtailment Actions</link:label>
    <link:label id="lab_arnc_ShutdownAndCurtailmentActionsMember_1D12E7086661C1D66B6696B482B6ADA0_label_en-US" xlink:label="lab_arnc_ShutdownAndCurtailmentActionsMember_1D12E7086661C1D66B6696B482B6ADA0" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Shutdown And Curtailment Actions [Member]</link:label>
    <link:label id="lab_arnc_ShutdownAndCurtailmentActionsMember_1D12E7086661C1D66B6696B482B6ADA0_documentation_en-US" xlink:label="lab_arnc_ShutdownAndCurtailmentActionsMember_1D12E7086661C1D66B6696B482B6ADA0" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Shutdown And Curtailment Actions [Member]</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_ShutdownAndCurtailmentActionsMember" xlink:label="loc_arnc_ShutdownAndCurtailmentActionsMember_1D12E7086661C1D66B6696B482B6ADA0" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_ShutdownAndCurtailmentActionsMember_1D12E7086661C1D66B6696B482B6ADA0" xlink:to="lab_arnc_ShutdownAndCurtailmentActionsMember_1D12E7086661C1D66B6696B482B6ADA0" xlink:type="arc" />
    <link:label id="lab_arnc_ClosureOfFiveFacilityMember_357CEEF35E0188C482EC96B482B68906_terseLabel_en-US" xlink:label="lab_arnc_ClosureOfFiveFacilityMember_357CEEF35E0188C482EC96B482B68906" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Closure Of Five Facility</link:label>
    <link:label id="lab_arnc_ClosureOfFiveFacilityMember_357CEEF35E0188C482EC96B482B68906_label_en-US" xlink:label="lab_arnc_ClosureOfFiveFacilityMember_357CEEF35E0188C482EC96B482B68906" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Closure Of Five Facility [Member]</link:label>
    <link:label id="lab_arnc_ClosureOfFiveFacilityMember_357CEEF35E0188C482EC96B482B68906_documentation_en-US" xlink:label="lab_arnc_ClosureOfFiveFacilityMember_357CEEF35E0188C482EC96B482B68906" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Closure of five facility.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_ClosureOfFiveFacilityMember" xlink:label="loc_arnc_ClosureOfFiveFacilityMember_357CEEF35E0188C482EC96B482B68906" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_ClosureOfFiveFacilityMember_357CEEF35E0188C482EC96B482B68906" xlink:to="lab_arnc_ClosureOfFiveFacilityMember_357CEEF35E0188C482EC96B482B68906" xlink:type="arc" />
    <link:label id="lab_arnc_RestructuringProgramsLayoffsTwoThousandSixteenMember_7E561E99307BD31D817896B482B6838F_terseLabel_en-US" xlink:label="lab_arnc_RestructuringProgramsLayoffsTwoThousandSixteenMember_7E561E99307BD31D817896B482B6838F" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Restructuring Programs Layoffs 2016</link:label>
    <link:label id="lab_arnc_RestructuringProgramsLayoffsTwoThousandSixteenMember_7E561E99307BD31D817896B482B6838F_label_en-US" xlink:label="lab_arnc_RestructuringProgramsLayoffsTwoThousandSixteenMember_7E561E99307BD31D817896B482B6838F" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Restructuring Programs Layoffs Two Thousand Sixteen Member</link:label>
    <link:label id="lab_arnc_RestructuringProgramsLayoffsTwoThousandSixteenMember_7E561E99307BD31D817896B482B6838F_documentation_en-US" xlink:label="lab_arnc_RestructuringProgramsLayoffsTwoThousandSixteenMember_7E561E99307BD31D817896B482B6838F" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Restructuring Programs Layoffs Two Thousand Sixteen Member</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_RestructuringProgramsLayoffsTwoThousandSixteenMember" xlink:label="loc_arnc_RestructuringProgramsLayoffsTwoThousandSixteenMember_7E561E99307BD31D817896B482B6838F" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_RestructuringProgramsLayoffsTwoThousandSixteenMember_7E561E99307BD31D817896B482B6838F" xlink:to="lab_arnc_RestructuringProgramsLayoffsTwoThousandSixteenMember_7E561E99307BD31D817896B482B6838F" xlink:type="arc" />
    <link:label id="lab_arnc_AssetImpairmentAndAcceleratedDepreciationMember_D57CD4DA99B65DB632F396B482B6E0C8_terseLabel_en-US" xlink:label="lab_arnc_AssetImpairmentAndAcceleratedDepreciationMember_D57CD4DA99B65DB632F396B482B6E0C8" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Asset Impairment and Accelerated Depreciation</link:label>
    <link:label id="lab_arnc_AssetImpairmentAndAcceleratedDepreciationMember_D57CD4DA99B65DB632F396B482B6E0C8_label_en-US" xlink:label="lab_arnc_AssetImpairmentAndAcceleratedDepreciationMember_D57CD4DA99B65DB632F396B482B6E0C8" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Asset Impairment And Accelerated Depreciation [Member]</link:label>
    <link:label id="lab_arnc_AssetImpairmentAndAcceleratedDepreciationMember_D57CD4DA99B65DB632F396B482B6E0C8_documentation_en-US" xlink:label="lab_arnc_AssetImpairmentAndAcceleratedDepreciationMember_D57CD4DA99B65DB632F396B482B6E0C8" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Asset impairment and accelerated depreciation.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_AssetImpairmentAndAcceleratedDepreciationMember" xlink:label="loc_arnc_AssetImpairmentAndAcceleratedDepreciationMember_D57CD4DA99B65DB632F396B482B6E0C8" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_AssetImpairmentAndAcceleratedDepreciationMember_D57CD4DA99B65DB632F396B482B6E0C8" xlink:to="lab_arnc_AssetImpairmentAndAcceleratedDepreciationMember_D57CD4DA99B65DB632F396B482B6E0C8" xlink:type="arc" />
    <link:label id="lab_arnc_AssetRetirementObligationsMember_1F6381D32F8A5013EAE296B482B62432_terseLabel_en-US" xlink:label="lab_arnc_AssetRetirementObligationsMember_1F6381D32F8A5013EAE296B482B62432" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Asset Retirement Obligations</link:label>
    <link:label id="lab_arnc_AssetRetirementObligationsMember_1F6381D32F8A5013EAE296B482B62432_label_en-US" xlink:label="lab_arnc_AssetRetirementObligationsMember_1F6381D32F8A5013EAE296B482B62432" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Asset Retirement Obligations [Member]</link:label>
    <link:label id="lab_arnc_AssetRetirementObligationsMember_1F6381D32F8A5013EAE296B482B62432_documentation_en-US" xlink:label="lab_arnc_AssetRetirementObligationsMember_1F6381D32F8A5013EAE296B482B62432" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Asset retirement obligations.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_AssetRetirementObligationsMember" xlink:label="loc_arnc_AssetRetirementObligationsMember_1F6381D32F8A5013EAE296B482B62432" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_AssetRetirementObligationsMember_1F6381D32F8A5013EAE296B482B62432" xlink:to="lab_arnc_AssetRetirementObligationsMember_1F6381D32F8A5013EAE296B482B62432" xlink:type="arc" />
    <link:label id="lab_stpr_TN_EE06F0C935BF45DB61D796B482BAF1D1_terseLabel_en-US" xlink:label="lab_stpr_TN_EE06F0C935BF45DB61D796B482BAF1D1" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Tennessee</link:label>
    <link:label id="lab_stpr_TN_EE06F0C935BF45DB61D796B482BAF1D1_label_en-US" xlink:label="lab_stpr_TN_EE06F0C935BF45DB61D796B482BAF1D1" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">TENNESSEE</link:label>
    <link:loc xlink:href="https://xbrl.sec.gov/stpr/2018/stpr-2018-01-31.xsd#stpr_TN" xlink:label="loc_stpr_TN_EE06F0C935BF45DB61D796B482BAF1D1" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_stpr_TN_EE06F0C935BF45DB61D796B482BAF1D1" xlink:to="lab_stpr_TN_EE06F0C935BF45DB61D796B482BAF1D1" xlink:type="arc" />
    <link:label id="lab_us-gaap_RelatedPartyTransactionAxis_81412AE56C3394729FFE96B482BA901E_terseLabel_en-US" xlink:label="lab_us-gaap_RelatedPartyTransactionAxis_81412AE56C3394729FFE96B482BA901E" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Related Party Transaction [Axis]</link:label>
    <link:label id="lab_us-gaap_RelatedPartyTransactionAxis_81412AE56C3394729FFE96B482BA901E_label_en-US" xlink:label="lab_us-gaap_RelatedPartyTransactionAxis_81412AE56C3394729FFE96B482BA901E" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Related Party Transaction [Axis]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RelatedPartyTransactionAxis" xlink:label="loc_us-gaap_RelatedPartyTransactionAxis_81412AE56C3394729FFE96B482BA901E" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RelatedPartyTransactionAxis_81412AE56C3394729FFE96B482BA901E" xlink:to="lab_us-gaap_RelatedPartyTransactionAxis_81412AE56C3394729FFE96B482BA901E" xlink:type="arc" />
    <link:label id="lab_us-gaap_RelatedPartyTransactionDomain_D3C6B41E20AE9BDD217A96B482BA8779_terseLabel_en-US" xlink:label="lab_us-gaap_RelatedPartyTransactionDomain_D3C6B41E20AE9BDD217A96B482BA8779" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Related Party Transaction [Domain]</link:label>
    <link:label id="lab_us-gaap_RelatedPartyTransactionDomain_D3C6B41E20AE9BDD217A96B482BA8779_label_en-US" xlink:label="lab_us-gaap_RelatedPartyTransactionDomain_D3C6B41E20AE9BDD217A96B482BA8779" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Related Party Transaction [Domain]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RelatedPartyTransactionDomain" xlink:label="loc_us-gaap_RelatedPartyTransactionDomain_D3C6B41E20AE9BDD217A96B482BA8779" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RelatedPartyTransactionDomain_D3C6B41E20AE9BDD217A96B482BA8779" xlink:to="lab_us-gaap_RelatedPartyTransactionDomain_D3C6B41E20AE9BDD217A96B482BA8779" xlink:type="arc" />
    <link:label id="lab_arnc_TollProcessingAndServicesAgreementMember_9DA98A9E3B702EDE289D96B482BA1FCA_terseLabel_en-US" xlink:label="lab_arnc_TollProcessingAndServicesAgreementMember_9DA98A9E3B702EDE289D96B482BA1FCA" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Toll Processing and Services Agreement</link:label>
    <link:label id="lab_arnc_TollProcessingAndServicesAgreementMember_9DA98A9E3B702EDE289D96B482BA1FCA_label_en-US" xlink:label="lab_arnc_TollProcessingAndServicesAgreementMember_9DA98A9E3B702EDE289D96B482BA1FCA" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Toll Processing and Services Agreement [Member]</link:label>
    <link:label id="lab_arnc_TollProcessingAndServicesAgreementMember_9DA98A9E3B702EDE289D96B482BA1FCA_documentation_en-US" xlink:label="lab_arnc_TollProcessingAndServicesAgreementMember_9DA98A9E3B702EDE289D96B482BA1FCA" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Toll processing and services agreement.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_TollProcessingAndServicesAgreementMember" xlink:label="loc_arnc_TollProcessingAndServicesAgreementMember_9DA98A9E3B702EDE289D96B482BA1FCA" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_TollProcessingAndServicesAgreementMember_9DA98A9E3B702EDE289D96B482BA1FCA" xlink:to="lab_arnc_TollProcessingAndServicesAgreementMember_9DA98A9E3B702EDE289D96B482BA1FCA" xlink:type="arc" />
    <link:label id="lab_arnc_NumberOfFacilitiesClosed_9EABF10F4E1B37D6E79F96B482BE9541_terseLabel_en-US" xlink:label="lab_arnc_NumberOfFacilitiesClosed_9EABF10F4E1B37D6E79F96B482BE9541" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Number of facilities closed</link:label>
    <link:label id="lab_arnc_NumberOfFacilitiesClosed_9EABF10F4E1B37D6E79F96B482BE9541_label_en-US" xlink:label="lab_arnc_NumberOfFacilitiesClosed_9EABF10F4E1B37D6E79F96B482BE9541" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Number Of Facilities Closed</link:label>
    <link:label id="lab_arnc_NumberOfFacilitiesClosed_9EABF10F4E1B37D6E79F96B482BE9541_documentation_en-US" xlink:label="lab_arnc_NumberOfFacilitiesClosed_9EABF10F4E1B37D6E79F96B482BE9541" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Number Of Facilities Closed</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_NumberOfFacilitiesClosed" xlink:label="loc_arnc_NumberOfFacilitiesClosed_9EABF10F4E1B37D6E79F96B482BE9541" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_NumberOfFacilitiesClosed_9EABF10F4E1B37D6E79F96B482BE9541" xlink:to="lab_arnc_NumberOfFacilitiesClosed_9EABF10F4E1B37D6E79F96B482BE9541" xlink:type="arc" />
    <link:label id="lab_us-gaap_OtherRestructuringCosts_820C976384DE01DEAB2E96B482BE580C_terseLabel_en-US" xlink:label="lab_us-gaap_OtherRestructuringCosts_820C976384DE01DEAB2E96B482BE580C" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Other exit costs</link:label>
    <link:label id="lab_us-gaap_OtherRestructuringCosts_820C976384DE01DEAB2E96B482BE580C_label_en-US" xlink:label="lab_us-gaap_OtherRestructuringCosts_820C976384DE01DEAB2E96B482BE580C" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Other Restructuring Costs</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_OtherRestructuringCosts" xlink:label="loc_us-gaap_OtherRestructuringCosts_820C976384DE01DEAB2E96B482BE580C" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OtherRestructuringCosts_820C976384DE01DEAB2E96B482BE580C" xlink:to="lab_us-gaap_OtherRestructuringCosts_820C976384DE01DEAB2E96B482BE580C" xlink:type="arc" />
    <link:label id="lab_us-gaap_CommitmentsAndContingenciesDisclosureTextBlock_CF6107654B868CA62426E244A9020318_terseLabel_en-US" xlink:label="lab_us-gaap_CommitmentsAndContingenciesDisclosureTextBlock_CF6107654B868CA62426E244A9020318" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Contingencies and Commitments</link:label>
    <link:label id="lab_us-gaap_CommitmentsAndContingenciesDisclosureTextBlock_CF6107654B868CA62426E244A9020318_label_en-US" xlink:label="lab_us-gaap_CommitmentsAndContingenciesDisclosureTextBlock_CF6107654B868CA62426E244A9020318" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Commitments and Contingencies Disclosure [Text Block]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_CommitmentsAndContingenciesDisclosureTextBlock" xlink:label="loc_us-gaap_CommitmentsAndContingenciesDisclosureTextBlock_CF6107654B868CA62426E244A9020318" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CommitmentsAndContingenciesDisclosureTextBlock_CF6107654B868CA62426E244A9020318" xlink:to="lab_us-gaap_CommitmentsAndContingenciesDisclosureTextBlock_CF6107654B868CA62426E244A9020318" xlink:type="arc" />
    <link:label id="lab_us-gaap_EquitySecuritiesMember_3EED340FF37822E3FECB7C362EF71E29_terseLabel_en-US" xlink:label="lab_us-gaap_EquitySecuritiesMember_3EED340FF37822E3FECB7C362EF71E29" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Equities</link:label>
    <link:label id="lab_us-gaap_EquitySecuritiesMember_3EED340FF37822E3FECB7C362EF71E29_label_en-US" xlink:label="lab_us-gaap_EquitySecuritiesMember_3EED340FF37822E3FECB7C362EF71E29" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Equity Securities [Member]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_EquitySecuritiesMember" xlink:label="loc_us-gaap_EquitySecuritiesMember_3EED340FF37822E3FECB7C362EF71E29" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_EquitySecuritiesMember_3EED340FF37822E3FECB7C362EF71E29" xlink:to="lab_us-gaap_EquitySecuritiesMember_3EED340FF37822E3FECB7C362EF71E29" xlink:type="arc" />
    <link:label id="lab_us-gaap_FixedIncomeSecuritiesMember_F272D3C916AB68C9BBCE7C362EF786E9_terseLabel_en-US" xlink:label="lab_us-gaap_FixedIncomeSecuritiesMember_F272D3C916AB68C9BBCE7C362EF786E9" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Fixed income</link:label>
    <link:label id="lab_us-gaap_FixedIncomeSecuritiesMember_F272D3C916AB68C9BBCE7C362EF786E9_label_en-US" xlink:label="lab_us-gaap_FixedIncomeSecuritiesMember_F272D3C916AB68C9BBCE7C362EF786E9" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Fixed Income Securities [Member]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_FixedIncomeSecuritiesMember" xlink:label="loc_us-gaap_FixedIncomeSecuritiesMember_F272D3C916AB68C9BBCE7C362EF786E9" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FixedIncomeSecuritiesMember_F272D3C916AB68C9BBCE7C362EF786E9" xlink:to="lab_us-gaap_FixedIncomeSecuritiesMember_F272D3C916AB68C9BBCE7C362EF786E9" xlink:type="arc" />
    <link:label id="lab_us-gaap_OtherInvestmentsMember_32214B6D999E2C1823D47C362EF77354_terseLabel_en-US" xlink:label="lab_us-gaap_OtherInvestmentsMember_32214B6D999E2C1823D47C362EF77354" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Other investments</link:label>
    <link:label id="lab_us-gaap_OtherInvestmentsMember_32214B6D999E2C1823D47C362EF77354_label_en-US" xlink:label="lab_us-gaap_OtherInvestmentsMember_32214B6D999E2C1823D47C362EF77354" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Other Investments [Member]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_OtherInvestmentsMember" xlink:label="loc_us-gaap_OtherInvestmentsMember_32214B6D999E2C1823D47C362EF77354" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OtherInvestmentsMember_32214B6D999E2C1823D47C362EF77354" xlink:to="lab_us-gaap_OtherInvestmentsMember_32214B6D999E2C1823D47C362EF77354" xlink:type="arc" />
    <link:label id="lab_us-gaap_DefinedBenefitPlanPlanAssetsTargetAllocationPercentage_2A04888F08EDA319C0F37C362EF7ED32_terseLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanPlanAssetsTargetAllocationPercentage_2A04888F08EDA319C0F37C362EF7ED32" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Policy range</link:label>
    <link:label id="lab_us-gaap_DefinedBenefitPlanPlanAssetsTargetAllocationPercentage_2A04888F08EDA319C0F37C362EF7ED32_label_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanPlanAssetsTargetAllocationPercentage_2A04888F08EDA319C0F37C362EF7ED32" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Plan Assets, Target Allocation, Percentage</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DefinedBenefitPlanPlanAssetsTargetAllocationPercentage" xlink:label="loc_us-gaap_DefinedBenefitPlanPlanAssetsTargetAllocationPercentage_2A04888F08EDA319C0F37C362EF7ED32" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanPlanAssetsTargetAllocationPercentage_2A04888F08EDA319C0F37C362EF7ED32" xlink:to="lab_us-gaap_DefinedBenefitPlanPlanAssetsTargetAllocationPercentage_2A04888F08EDA319C0F37C362EF7ED32" xlink:type="arc" />
    <link:label id="lab_us-gaap_DefinedBenefitPlanWeightedAverageAssetAllocations_11A91CBB571BA829827A7C362EF7CB17_terseLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanWeightedAverageAssetAllocations_11A91CBB571BA829827A7C362EF7CB17" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Defined benefit plan, asset allocations</link:label>
    <link:label id="lab_us-gaap_DefinedBenefitPlanWeightedAverageAssetAllocations_11A91CBB571BA829827A7C362EF7CB17_label_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanWeightedAverageAssetAllocations_11A91CBB571BA829827A7C362EF7CB17" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Plan Assets, Actual Allocation, Percentage</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DefinedBenefitPlanWeightedAverageAssetAllocations" xlink:label="loc_us-gaap_DefinedBenefitPlanWeightedAverageAssetAllocations_11A91CBB571BA829827A7C362EF7CB17" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanWeightedAverageAssetAllocations_11A91CBB571BA829827A7C362EF7CB17" xlink:to="lab_us-gaap_DefinedBenefitPlanWeightedAverageAssetAllocations_11A91CBB571BA829827A7C362EF7CB17" xlink:type="arc" />
    <link:label id="lab_us-gaap_GoodwillRollForward_8A3FD45DB02B699DB5D3E244A9B2892A_terseLabel_en-US" xlink:label="lab_us-gaap_GoodwillRollForward_8A3FD45DB02B699DB5D3E244A9B2892A" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Goodwill [Roll Forward]</link:label>
    <link:label id="lab_us-gaap_GoodwillRollForward_8A3FD45DB02B699DB5D3E244A9B2892A_label_en-US" xlink:label="lab_us-gaap_GoodwillRollForward_8A3FD45DB02B699DB5D3E244A9B2892A" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Goodwill [Roll Forward]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_GoodwillRollForward" xlink:label="loc_us-gaap_GoodwillRollForward_8A3FD45DB02B699DB5D3E244A9B2892A" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_GoodwillRollForward_8A3FD45DB02B699DB5D3E244A9B2892A" xlink:to="lab_us-gaap_GoodwillRollForward_8A3FD45DB02B699DB5D3E244A9B2892A" xlink:type="arc" />
    <link:label id="lab_us-gaap_GoodwillGross_13463B4D513EBE13AEF5E244A9B29DF0_periodStartLabel_en-US" xlink:label="lab_us-gaap_GoodwillGross_13463B4D513EBE13AEF5E244A9B29DF0" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel" xlink:type="resource" xml:lang="en-US">Goodwill gross, beginning balance</link:label>
    <link:label id="lab_us-gaap_GoodwillGross_13463B4D513EBE13AEF5E244A9B29DF0_label_en-US" xlink:label="lab_us-gaap_GoodwillGross_13463B4D513EBE13AEF5E244A9B29DF0" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Goodwill, Gross</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_GoodwillGross" xlink:label="loc_us-gaap_GoodwillGross_13463B4D513EBE13AEF5E244A9B29DF0" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_GoodwillGross_13463B4D513EBE13AEF5E244A9B29DF0" xlink:to="lab_us-gaap_GoodwillGross_13463B4D513EBE13AEF5E244A9B29DF0" xlink:type="arc" />
    <link:label id="lab_us-gaap_GoodwillImpairedAccumulatedImpairmentLoss_72C37CB3A7E315ADBA8CE244A9B2262D_negatedPeriodStartLabel_en-US" xlink:label="lab_us-gaap_GoodwillImpairedAccumulatedImpairmentLoss_72C37CB3A7E315ADBA8CE244A9B2262D" xlink:role="http://www.xbrl.org/2009/role/negatedPeriodStartLabel" xlink:type="resource" xml:lang="en-US">Accumulated impairment losses</link:label>
    <link:label id="lab_us-gaap_GoodwillImpairedAccumulatedImpairmentLoss_72C37CB3A7E315ADBA8CE244A9B2262D_label_en-US" xlink:label="lab_us-gaap_GoodwillImpairedAccumulatedImpairmentLoss_72C37CB3A7E315ADBA8CE244A9B2262D" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Goodwill, Impaired, Accumulated Impairment Loss</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_GoodwillImpairedAccumulatedImpairmentLoss" xlink:label="loc_us-gaap_GoodwillImpairedAccumulatedImpairmentLoss_72C37CB3A7E315ADBA8CE244A9B2262D" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_GoodwillImpairedAccumulatedImpairmentLoss_72C37CB3A7E315ADBA8CE244A9B2262D" xlink:to="lab_us-gaap_GoodwillImpairedAccumulatedImpairmentLoss_72C37CB3A7E315ADBA8CE244A9B2262D" xlink:type="arc" />
    <link:label id="lab_us-gaap_Goodwill_5A46DB5D054BF1E63A22E244A9B27C82_periodStartLabel_en-US" xlink:label="lab_us-gaap_Goodwill_5A46DB5D054BF1E63A22E244A9B27C82" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel" xlink:type="resource" xml:lang="en-US">Goodwill, net</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_Goodwill" xlink:label="loc_us-gaap_Goodwill_5A46DB5D054BF1E63A22E244A9B27C82" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_Goodwill_5A46DB5D054BF1E63A22E244A9B27C82" xlink:to="lab_us-gaap_Goodwill_5A46DB5D054BF1E63A22E244A9B27C82" xlink:type="arc" />
    <link:label id="lab_arnc_GoodwillAcquisitionAndDivestitures_65D957419413502986C4E244A9B294FD_negatedTerseLabel_en-US" xlink:label="lab_arnc_GoodwillAcquisitionAndDivestitures_65D957419413502986C4E244A9B294FD" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:type="resource" xml:lang="en-US">Acquisitions and Divestitures</link:label>
    <link:label id="lab_arnc_GoodwillAcquisitionAndDivestitures_65D957419413502986C4E244A9B294FD_label_en-US" xlink:label="lab_arnc_GoodwillAcquisitionAndDivestitures_65D957419413502986C4E244A9B294FD" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Goodwill Acquisition And Divestitures</link:label>
    <link:label id="lab_arnc_GoodwillAcquisitionAndDivestitures_65D957419413502986C4E244A9B294FD_documentation_en-US" xlink:label="lab_arnc_GoodwillAcquisitionAndDivestitures_65D957419413502986C4E244A9B294FD" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Goodwill acquisition and divestitures.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_GoodwillAcquisitionAndDivestitures" xlink:label="loc_arnc_GoodwillAcquisitionAndDivestitures_65D957419413502986C4E244A9B294FD" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_GoodwillAcquisitionAndDivestitures_65D957419413502986C4E244A9B294FD" xlink:to="lab_arnc_GoodwillAcquisitionAndDivestitures_65D957419413502986C4E244A9B294FD" xlink:type="arc" />
    <link:label id="lab_us-gaap_GoodwillImpairmentLoss_C8195E9BB689885D3294E244A9B29C18_negatedLabel_en-US" xlink:label="lab_us-gaap_GoodwillImpairmentLoss_C8195E9BB689885D3294E244A9B29C18" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xml:lang="en-US">Impairment</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_GoodwillImpairmentLoss" xlink:label="loc_us-gaap_GoodwillImpairmentLoss_C8195E9BB689885D3294E244A9B29C18" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_GoodwillImpairmentLoss_C8195E9BB689885D3294E244A9B29C18" xlink:to="lab_us-gaap_GoodwillImpairmentLoss_C8195E9BB689885D3294E244A9B29C18" xlink:type="arc" />
    <link:label id="lab_us-gaap_GoodwillForeignCurrencyTranslationGainLoss_45BFF2D1E161DEA20641E244A9B2DF48_terseLabel_en-US" xlink:label="lab_us-gaap_GoodwillForeignCurrencyTranslationGainLoss_45BFF2D1E161DEA20641E244A9B2DF48" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Translation and other</link:label>
    <link:label id="lab_us-gaap_GoodwillForeignCurrencyTranslationGainLoss_45BFF2D1E161DEA20641E244A9B2DF48_label_en-US" xlink:label="lab_us-gaap_GoodwillForeignCurrencyTranslationGainLoss_45BFF2D1E161DEA20641E244A9B2DF48" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Goodwill, Foreign Currency Translation Gain (Loss)</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_GoodwillForeignCurrencyTranslationGainLoss" xlink:label="loc_us-gaap_GoodwillForeignCurrencyTranslationGainLoss_45BFF2D1E161DEA20641E244A9B2DF48" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_GoodwillForeignCurrencyTranslationGainLoss_45BFF2D1E161DEA20641E244A9B2DF48" xlink:to="lab_us-gaap_GoodwillForeignCurrencyTranslationGainLoss_45BFF2D1E161DEA20641E244A9B2DF48" xlink:type="arc" />
    <link:label id="lab_us-gaap_GoodwillGross_175BA88ACC9C5163174CE244A9B2245E_periodEndLabel_en-US" xlink:label="lab_us-gaap_GoodwillGross_175BA88ACC9C5163174CE244A9B2245E" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel" xlink:type="resource" xml:lang="en-US">Goodwill gross, ending balance</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_GoodwillGross" xlink:label="loc_us-gaap_GoodwillGross_175BA88ACC9C5163174CE244A9B2245E" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_GoodwillGross_175BA88ACC9C5163174CE244A9B2245E" xlink:to="lab_us-gaap_GoodwillGross_175BA88ACC9C5163174CE244A9B2245E" xlink:type="arc" />
    <link:label id="lab_us-gaap_GoodwillImpairedAccumulatedImpairmentLoss_192906943E9C77815248E244A9B2CDF9_negatedPeriodEndLabel_en-US" xlink:label="lab_us-gaap_GoodwillImpairedAccumulatedImpairmentLoss_192906943E9C77815248E244A9B2CDF9" xlink:role="http://www.xbrl.org/2009/role/negatedPeriodEndLabel" xlink:type="resource" xml:lang="en-US">Accumulated impairment losses</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_GoodwillImpairedAccumulatedImpairmentLoss" xlink:label="loc_us-gaap_GoodwillImpairedAccumulatedImpairmentLoss_192906943E9C77815248E244A9B2CDF9" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_GoodwillImpairedAccumulatedImpairmentLoss_192906943E9C77815248E244A9B2CDF9" xlink:to="lab_us-gaap_GoodwillImpairedAccumulatedImpairmentLoss_192906943E9C77815248E244A9B2CDF9" xlink:type="arc" />
    <link:label id="lab_us-gaap_Goodwill_1073D6C03A8A4CEA7454E244A9B2107B_totalLabel_en-US" xlink:label="lab_us-gaap_Goodwill_1073D6C03A8A4CEA7454E244A9B2107B" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Goodwill, ending balance</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_Goodwill" xlink:label="loc_us-gaap_Goodwill_1073D6C03A8A4CEA7454E244A9B2107B" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_Goodwill_1073D6C03A8A4CEA7454E244A9B2107B" xlink:to="lab_us-gaap_Goodwill_1073D6C03A8A4CEA7454E244A9B2107B" xlink:type="arc" />
    <link:label id="lab_us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable_71FB1C8F196DC869E70895CE5ED3833A_terseLabel_en-US" xlink:label="lab_us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable_71FB1C8F196DC869E70895CE5ED3833A" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Schedule of Finite-Lived Intangible Assets [Table]</link:label>
    <link:label id="lab_us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable_71FB1C8F196DC869E70895CE5ED3833A_label_en-US" xlink:label="lab_us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable_71FB1C8F196DC869E70895CE5ED3833A" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Schedule of Finite-Lived Intangible Assets [Table]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable" xlink:label="loc_us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable_71FB1C8F196DC869E70895CE5ED3833A" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable_71FB1C8F196DC869E70895CE5ED3833A" xlink:to="lab_us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable_71FB1C8F196DC869E70895CE5ED3833A" xlink:type="arc" />
    <link:label id="lab_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_F01D990E09E3407A16D195CE5ED388DB_terseLabel_en-US" xlink:label="lab_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_F01D990E09E3407A16D195CE5ED388DB" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Finite-Lived Intangible Assets by Major Class [Axis]</link:label>
    <link:label id="lab_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_F01D990E09E3407A16D195CE5ED388DB_label_en-US" xlink:label="lab_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_F01D990E09E3407A16D195CE5ED388DB" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Finite-Lived Intangible Assets by Major Class [Axis]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_F01D990E09E3407A16D195CE5ED388DB" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_F01D990E09E3407A16D195CE5ED388DB" xlink:to="lab_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_F01D990E09E3407A16D195CE5ED388DB" xlink:type="arc" />
    <link:label id="lab_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_BE4F0ADC91F4B4B0E21E95CE5ED3587F_terseLabel_en-US" xlink:label="lab_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_BE4F0ADC91F4B4B0E21E95CE5ED3587F" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Finite-Lived Intangible Assets, Major Class Name [Domain]</link:label>
    <link:label id="lab_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_BE4F0ADC91F4B4B0E21E95CE5ED3587F_label_en-US" xlink:label="lab_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_BE4F0ADC91F4B4B0E21E95CE5ED3587F" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Finite-Lived Intangible Assets, Major Class Name [Domain]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_BE4F0ADC91F4B4B0E21E95CE5ED3587F" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_BE4F0ADC91F4B4B0E21E95CE5ED3587F" xlink:to="lab_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_BE4F0ADC91F4B4B0E21E95CE5ED3587F" xlink:type="arc" />
    <link:label id="lab_us-gaap_ComputerSoftwareIntangibleAssetMember_E3ADB0147B701508FD4E95CE5ED361C7_terseLabel_en-US" xlink:label="lab_us-gaap_ComputerSoftwareIntangibleAssetMember_E3ADB0147B701508FD4E95CE5ED361C7" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Software</link:label>
    <link:label id="lab_us-gaap_ComputerSoftwareIntangibleAssetMember_E3ADB0147B701508FD4E95CE5ED361C7_label_en-US" xlink:label="lab_us-gaap_ComputerSoftwareIntangibleAssetMember_E3ADB0147B701508FD4E95CE5ED361C7" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Computer Software, Intangible Asset [Member]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ComputerSoftwareIntangibleAssetMember" xlink:label="loc_us-gaap_ComputerSoftwareIntangibleAssetMember_E3ADB0147B701508FD4E95CE5ED361C7" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ComputerSoftwareIntangibleAssetMember_E3ADB0147B701508FD4E95CE5ED361C7" xlink:to="lab_us-gaap_ComputerSoftwareIntangibleAssetMember_E3ADB0147B701508FD4E95CE5ED361C7" xlink:type="arc" />
    <link:label id="lab_us-gaap_OtherIntangibleAssetsMember_20F963CE1F7D4F5B212495CE5ED3069C_terseLabel_en-US" xlink:label="lab_us-gaap_OtherIntangibleAssetsMember_20F963CE1F7D4F5B212495CE5ED3069C" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Other intangible assets</link:label>
    <link:label id="lab_us-gaap_OtherIntangibleAssetsMember_20F963CE1F7D4F5B212495CE5ED3069C_label_en-US" xlink:label="lab_us-gaap_OtherIntangibleAssetsMember_20F963CE1F7D4F5B212495CE5ED3069C" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Other Intangible Assets [Member]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_OtherIntangibleAssetsMember" xlink:label="loc_us-gaap_OtherIntangibleAssetsMember_20F963CE1F7D4F5B212495CE5ED3069C" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OtherIntangibleAssetsMember_20F963CE1F7D4F5B212495CE5ED3069C" xlink:to="lab_us-gaap_OtherIntangibleAssetsMember_20F963CE1F7D4F5B212495CE5ED3069C" xlink:type="arc" />
    <link:label id="lab_us-gaap_FiniteLivedIntangibleAssetsLineItems_28D4E3BBBEE270E4D38A95CE5ED77860_terseLabel_en-US" xlink:label="lab_us-gaap_FiniteLivedIntangibleAssetsLineItems_28D4E3BBBEE270E4D38A95CE5ED77860" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Finite-Lived Intangible Assets [Line Items]</link:label>
    <link:label id="lab_us-gaap_FiniteLivedIntangibleAssetsLineItems_28D4E3BBBEE270E4D38A95CE5ED77860_label_en-US" xlink:label="lab_us-gaap_FiniteLivedIntangibleAssetsLineItems_28D4E3BBBEE270E4D38A95CE5ED77860" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Finite-Lived Intangible Assets [Line Items]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsLineItems" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsLineItems_28D4E3BBBEE270E4D38A95CE5ED77860" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsLineItems_28D4E3BBBEE270E4D38A95CE5ED77860" xlink:to="lab_us-gaap_FiniteLivedIntangibleAssetsLineItems_28D4E3BBBEE270E4D38A95CE5ED77860" xlink:type="arc" />
    <link:label id="lab_us-gaap_FiniteLivedIntangibleAssetUsefulLife_DA9E66346D6A2E53872B95CE5ED721FF_terseLabel_en-US" xlink:label="lab_us-gaap_FiniteLivedIntangibleAssetUsefulLife_DA9E66346D6A2E53872B95CE5ED721FF" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Weighted-average useful lives of other intangible assets</link:label>
    <link:label id="lab_us-gaap_FiniteLivedIntangibleAssetUsefulLife_DA9E66346D6A2E53872B95CE5ED721FF_label_en-US" xlink:label="lab_us-gaap_FiniteLivedIntangibleAssetUsefulLife_DA9E66346D6A2E53872B95CE5ED721FF" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Finite-Lived Intangible Asset, Useful Life</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetUsefulLife" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetUsefulLife_DA9E66346D6A2E53872B95CE5ED721FF" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetUsefulLife_DA9E66346D6A2E53872B95CE5ED721FF" xlink:to="lab_us-gaap_FiniteLivedIntangibleAssetUsefulLife_DA9E66346D6A2E53872B95CE5ED721FF" xlink:type="arc" />
    <link:label id="lab_us-gaap_ComputerSoftwareIntangibleAssetMember_20FB3C7815910A9FEF74E244A9A28310_verboseLabel_en-US" xlink:label="lab_us-gaap_ComputerSoftwareIntangibleAssetMember_20FB3C7815910A9FEF74E244A9A28310" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Computer software</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ComputerSoftwareIntangibleAssetMember" xlink:label="loc_us-gaap_ComputerSoftwareIntangibleAssetMember_20FB3C7815910A9FEF74E244A9A28310" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ComputerSoftwareIntangibleAssetMember_20FB3C7815910A9FEF74E244A9A28310" xlink:to="lab_us-gaap_ComputerSoftwareIntangibleAssetMember_20FB3C7815910A9FEF74E244A9A28310" xlink:type="arc" />
    <link:label id="lab_arnc_PatentLicenseAgreementMember_C32104AB7E3EA553F287E244A9A2FDB6_terseLabel_en-US" xlink:label="lab_arnc_PatentLicenseAgreementMember_C32104AB7E3EA553F287E244A9A2FDB6" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Patents and licenses</link:label>
    <link:label id="lab_arnc_PatentLicenseAgreementMember_C32104AB7E3EA553F287E244A9A2FDB6_label_en-US" xlink:label="lab_arnc_PatentLicenseAgreementMember_C32104AB7E3EA553F287E244A9A2FDB6" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Patent License Agreement [Member]</link:label>
    <link:label id="lab_arnc_PatentLicenseAgreementMember_C32104AB7E3EA553F287E244A9A2FDB6_documentation_en-US" xlink:label="lab_arnc_PatentLicenseAgreementMember_C32104AB7E3EA553F287E244A9A2FDB6" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Patent license agreement.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_PatentLicenseAgreementMember" xlink:label="loc_arnc_PatentLicenseAgreementMember_C32104AB7E3EA553F287E244A9A2FDB6" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_PatentLicenseAgreementMember_C32104AB7E3EA553F287E244A9A2FDB6" xlink:to="lab_arnc_PatentLicenseAgreementMember_C32104AB7E3EA553F287E244A9A2FDB6" xlink:type="arc" />
    <link:label id="lab_us-gaap_FiniteLivedIntangibleAssetsGross_CF8AFDFA837C9068C412E244A9A2DEA2_terseLabel_en-US" xlink:label="lab_us-gaap_FiniteLivedIntangibleAssetsGross_CF8AFDFA837C9068C412E244A9A2DEA2" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Gross carrying amount</link:label>
    <link:label id="lab_us-gaap_FiniteLivedIntangibleAssetsGross_CF8AFDFA837C9068C412E244A9A2DEA2_label_en-US" xlink:label="lab_us-gaap_FiniteLivedIntangibleAssetsGross_CF8AFDFA837C9068C412E244A9A2DEA2" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Finite-Lived Intangible Assets, Gross</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsGross" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsGross_CF8AFDFA837C9068C412E244A9A2DEA2" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsGross_CF8AFDFA837C9068C412E244A9A2DEA2" xlink:to="lab_us-gaap_FiniteLivedIntangibleAssetsGross_CF8AFDFA837C9068C412E244A9A2DEA2" xlink:type="arc" />
    <link:label id="lab_us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization_F22CCB45549EA519EC85E244A9A2291F_negatedLabel_en-US" xlink:label="lab_us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization_F22CCB45549EA519EC85E244A9A2291F" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xml:lang="en-US">Accumulated amortization</link:label>
    <link:label id="lab_us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization_F22CCB45549EA519EC85E244A9A2291F_label_en-US" xlink:label="lab_us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization_F22CCB45549EA519EC85E244A9A2291F" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Finite-Lived Intangible Assets, Accumulated Amortization</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization_F22CCB45549EA519EC85E244A9A2291F" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization_F22CCB45549EA519EC85E244A9A2291F" xlink:to="lab_us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization_F22CCB45549EA519EC85E244A9A2291F" xlink:type="arc" />
    <link:label id="lab_us-gaap_FiniteLivedIntangibleAssetsNet_37FB3306FC77A254A97BE244A9A24CFD_totalLabel_en-US" xlink:label="lab_us-gaap_FiniteLivedIntangibleAssetsNet_37FB3306FC77A254A97BE244A9A24CFD" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Intangibles, net</link:label>
    <link:label id="lab_us-gaap_FiniteLivedIntangibleAssetsNet_37FB3306FC77A254A97BE244A9A24CFD_label_en-US" xlink:label="lab_us-gaap_FiniteLivedIntangibleAssetsNet_37FB3306FC77A254A97BE244A9A24CFD" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Finite-Lived Intangible Assets, Net</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsNet" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsNet_37FB3306FC77A254A97BE244A9A24CFD" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsNet_37FB3306FC77A254A97BE244A9A24CFD" xlink:to="lab_us-gaap_FiniteLivedIntangibleAssetsNet_37FB3306FC77A254A97BE244A9A24CFD" xlink:type="arc" />
    <link:label id="lab_us-gaap_IndefiniteLivedIntangibleAssetsExcludingGoodwill_B2218CAC6907447072A8E244A9A27012_terseLabel_en-US" xlink:label="lab_us-gaap_IndefiniteLivedIntangibleAssetsExcludingGoodwill_B2218CAC6907447072A8E244A9A27012" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Indefinite-lived trade names and trademarks</link:label>
    <link:label id="lab_us-gaap_IndefiniteLivedIntangibleAssetsExcludingGoodwill_B2218CAC6907447072A8E244A9A27012_label_en-US" xlink:label="lab_us-gaap_IndefiniteLivedIntangibleAssetsExcludingGoodwill_B2218CAC6907447072A8E244A9A27012" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Indefinite-lived Intangible Assets (Excluding Goodwill)</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_IndefiniteLivedIntangibleAssetsExcludingGoodwill" xlink:label="loc_us-gaap_IndefiniteLivedIntangibleAssetsExcludingGoodwill_B2218CAC6907447072A8E244A9A27012" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IndefiniteLivedIntangibleAssetsExcludingGoodwill_B2218CAC6907447072A8E244A9A27012" xlink:to="lab_us-gaap_IndefiniteLivedIntangibleAssetsExcludingGoodwill_B2218CAC6907447072A8E244A9A27012" xlink:type="arc" />
    <link:label id="lab_us-gaap_OtherIntangibleAssetsNet_8CE2D5A1F393A4750020E244A9A2EB6D_totalLabel_en-US" xlink:label="lab_us-gaap_OtherIntangibleAssetsNet_8CE2D5A1F393A4750020E244A9A2EB6D" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Total other intangible assets, gross</link:label>
    <link:label id="lab_us-gaap_OtherIntangibleAssetsNet_8CE2D5A1F393A4750020E244A9A2EB6D_label_en-US" xlink:label="lab_us-gaap_OtherIntangibleAssetsNet_8CE2D5A1F393A4750020E244A9A2EB6D" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Other Intangible Assets, Net</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_OtherIntangibleAssetsNet" xlink:label="loc_us-gaap_OtherIntangibleAssetsNet_8CE2D5A1F393A4750020E244A9A2EB6D" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OtherIntangibleAssetsNet_8CE2D5A1F393A4750020E244A9A2EB6D" xlink:to="lab_us-gaap_OtherIntangibleAssetsNet_8CE2D5A1F393A4750020E244A9A2EB6D" xlink:type="arc" />
    <link:label id="lab_us-gaap_IntangibleAssetsNetExcludingGoodwill_A07604D8E15B3A82FFCCE244A9A23159_totalLabel_en-US" xlink:label="lab_us-gaap_IntangibleAssetsNetExcludingGoodwill_A07604D8E15B3A82FFCCE244A9A23159" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Total other intangible assets, net</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_IntangibleAssetsNetExcludingGoodwill" xlink:label="loc_us-gaap_IntangibleAssetsNetExcludingGoodwill_A07604D8E15B3A82FFCCE244A9A23159" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IntangibleAssetsNetExcludingGoodwill_A07604D8E15B3A82FFCCE244A9A23159" xlink:to="lab_us-gaap_IntangibleAssetsNetExcludingGoodwill_A07604D8E15B3A82FFCCE244A9A23159" xlink:type="arc" />
    <link:label id="lab_us-gaap_GoodwillAndIntangibleAssetsDisclosureTextBlock_798CCE8A1297001F3B79E244A9BA58DA_terseLabel_en-US" xlink:label="lab_us-gaap_GoodwillAndIntangibleAssetsDisclosureTextBlock_798CCE8A1297001F3B79E244A9BA58DA" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Goodwill and Other Intangible Assets</link:label>
    <link:label id="lab_us-gaap_GoodwillAndIntangibleAssetsDisclosureTextBlock_798CCE8A1297001F3B79E244A9BA58DA_label_en-US" xlink:label="lab_us-gaap_GoodwillAndIntangibleAssetsDisclosureTextBlock_798CCE8A1297001F3B79E244A9BA58DA" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Goodwill and Intangible Assets Disclosure [Text Block]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_GoodwillAndIntangibleAssetsDisclosureTextBlock" xlink:label="loc_us-gaap_GoodwillAndIntangibleAssetsDisclosureTextBlock_798CCE8A1297001F3B79E244A9BA58DA" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_GoodwillAndIntangibleAssetsDisclosureTextBlock_798CCE8A1297001F3B79E244A9BA58DA" xlink:to="lab_us-gaap_GoodwillAndIntangibleAssetsDisclosureTextBlock_798CCE8A1297001F3B79E244A9BA58DA" xlink:type="arc" />
    <link:label id="lab_us-gaap_TransfersAndServicingOfFinancialAssetsTextBlock_B484B26E0594A25A5E5B7C362D82C837_terseLabel_en-US" xlink:label="lab_us-gaap_TransfersAndServicingOfFinancialAssetsTextBlock_B484B26E0594A25A5E5B7C362D82C837" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Receivables</link:label>
    <link:label id="lab_us-gaap_TransfersAndServicingOfFinancialAssetsTextBlock_B484B26E0594A25A5E5B7C362D82C837_label_en-US" xlink:label="lab_us-gaap_TransfersAndServicingOfFinancialAssetsTextBlock_B484B26E0594A25A5E5B7C362D82C837" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Transfers and Servicing of Financial Assets [Text Block]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_TransfersAndServicingOfFinancialAssetsTextBlock" xlink:label="loc_us-gaap_TransfersAndServicingOfFinancialAssetsTextBlock_B484B26E0594A25A5E5B7C362D82C837" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialAssetsTextBlock_B484B26E0594A25A5E5B7C362D82C837" xlink:to="lab_us-gaap_TransfersAndServicingOfFinancialAssetsTextBlock_B484B26E0594A25A5E5B7C362D82C837" xlink:type="arc" />
    <link:label id="lab_us-gaap_FairValueByFairValueHierarchyLevelAxis_AB3C9521CDE2C19D23C2DEFAB9A6FAA2_terseLabel_en-US" xlink:label="lab_us-gaap_FairValueByFairValueHierarchyLevelAxis_AB3C9521CDE2C19D23C2DEFAB9A6FAA2" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Fair Value Hierarchy and NAV [Axis]</link:label>
    <link:label id="lab_us-gaap_FairValueByFairValueHierarchyLevelAxis_AB3C9521CDE2C19D23C2DEFAB9A6FAA2_label_en-US" xlink:label="lab_us-gaap_FairValueByFairValueHierarchyLevelAxis_AB3C9521CDE2C19D23C2DEFAB9A6FAA2" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Fair Value Hierarchy and NAV [Axis]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_FairValueByFairValueHierarchyLevelAxis" xlink:label="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_AB3C9521CDE2C19D23C2DEFAB9A6FAA2" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_AB3C9521CDE2C19D23C2DEFAB9A6FAA2" xlink:to="lab_us-gaap_FairValueByFairValueHierarchyLevelAxis_AB3C9521CDE2C19D23C2DEFAB9A6FAA2" xlink:type="arc" />
    <link:label id="lab_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_84767AD0DA3744E97D3EDEFAB9A6BD47_terseLabel_en-US" xlink:label="lab_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_84767AD0DA3744E97D3EDEFAB9A6BD47" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Fair Value Hierarchy and NAV [Domain]</link:label>
    <link:label id="lab_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_84767AD0DA3744E97D3EDEFAB9A6BD47_label_en-US" xlink:label="lab_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_84767AD0DA3744E97D3EDEFAB9A6BD47" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Fair Value Hierarchy and NAV [Domain]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_FairValueMeasurementsFairValueHierarchyDomain" xlink:label="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_84767AD0DA3744E97D3EDEFAB9A6BD47" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_84767AD0DA3744E97D3EDEFAB9A6BD47" xlink:to="lab_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_84767AD0DA3744E97D3EDEFAB9A6BD47" xlink:type="arc" />
    <link:label id="lab_us-gaap_FairValueInputsLevel1Member_062E621ECA42FB147760DEFAB9A60B2C_terseLabel_en-US" xlink:label="lab_us-gaap_FairValueInputsLevel1Member_062E621ECA42FB147760DEFAB9A60B2C" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Level 1</link:label>
    <link:label id="lab_us-gaap_FairValueInputsLevel1Member_062E621ECA42FB147760DEFAB9A60B2C_label_en-US" xlink:label="lab_us-gaap_FairValueInputsLevel1Member_062E621ECA42FB147760DEFAB9A60B2C" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Fair Value, Inputs, Level 1 [Member]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_FairValueInputsLevel1Member" xlink:label="loc_us-gaap_FairValueInputsLevel1Member_062E621ECA42FB147760DEFAB9A60B2C" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FairValueInputsLevel1Member_062E621ECA42FB147760DEFAB9A60B2C" xlink:to="lab_us-gaap_FairValueInputsLevel1Member_062E621ECA42FB147760DEFAB9A60B2C" xlink:type="arc" />
    <link:label id="lab_us-gaap_FairValueInputsLevel2Member_67B52D77EB34BFE4A265DEFAB9A6E43C_terseLabel_en-US" xlink:label="lab_us-gaap_FairValueInputsLevel2Member_67B52D77EB34BFE4A265DEFAB9A6E43C" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Level 2</link:label>
    <link:label id="lab_us-gaap_FairValueInputsLevel2Member_67B52D77EB34BFE4A265DEFAB9A6E43C_label_en-US" xlink:label="lab_us-gaap_FairValueInputsLevel2Member_67B52D77EB34BFE4A265DEFAB9A6E43C" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Fair Value, Inputs, Level 2 [Member]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_FairValueInputsLevel2Member" xlink:label="loc_us-gaap_FairValueInputsLevel2Member_67B52D77EB34BFE4A265DEFAB9A6E43C" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FairValueInputsLevel2Member_67B52D77EB34BFE4A265DEFAB9A6E43C" xlink:to="lab_us-gaap_FairValueInputsLevel2Member_67B52D77EB34BFE4A265DEFAB9A6E43C" xlink:type="arc" />
    <link:label id="lab_us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis_EAAB2EFA349F521E8CC0DEFAB9A6AA7E_terseLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis_EAAB2EFA349F521E8CC0DEFAB9A6AA7E" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Plan Assets, Category [Axis]</link:label>
    <link:label id="lab_us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis_EAAB2EFA349F521E8CC0DEFAB9A6AA7E_label_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis_EAAB2EFA349F521E8CC0DEFAB9A6AA7E" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Plan Assets, Category [Axis]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis" xlink:label="loc_us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis_EAAB2EFA349F521E8CC0DEFAB9A6AA7E" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis_EAAB2EFA349F521E8CC0DEFAB9A6AA7E" xlink:to="lab_us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis_EAAB2EFA349F521E8CC0DEFAB9A6AA7E" xlink:type="arc" />
    <link:label id="lab_us-gaap_PlanAssetCategoriesDomain_357510A72FD5C7130540DEFAB9A659D5_terseLabel_en-US" xlink:label="lab_us-gaap_PlanAssetCategoriesDomain_357510A72FD5C7130540DEFAB9A659D5" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Plan Assets, Category [Domain]</link:label>
    <link:label id="lab_us-gaap_PlanAssetCategoriesDomain_357510A72FD5C7130540DEFAB9A659D5_label_en-US" xlink:label="lab_us-gaap_PlanAssetCategoriesDomain_357510A72FD5C7130540DEFAB9A659D5" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Plan Assets, Category [Domain]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PlanAssetCategoriesDomain" xlink:label="loc_us-gaap_PlanAssetCategoriesDomain_357510A72FD5C7130540DEFAB9A659D5" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PlanAssetCategoriesDomain_357510A72FD5C7130540DEFAB9A659D5" xlink:to="lab_us-gaap_PlanAssetCategoriesDomain_357510A72FD5C7130540DEFAB9A659D5" xlink:type="arc" />
    <link:label id="lab_us-gaap_EquityFundsMember_726A7807B10B9A56BC34DEFAB9A8721D_terseLabel_en-US" xlink:label="lab_us-gaap_EquityFundsMember_726A7807B10B9A56BC34DEFAB9A8721D" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Equity securities</link:label>
    <link:label id="lab_us-gaap_EquityFundsMember_726A7807B10B9A56BC34DEFAB9A8721D_label_en-US" xlink:label="lab_us-gaap_EquityFundsMember_726A7807B10B9A56BC34DEFAB9A8721D" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Equity Funds [Member]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_EquityFundsMember" xlink:label="loc_us-gaap_EquityFundsMember_726A7807B10B9A56BC34DEFAB9A8721D" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_EquityFundsMember_726A7807B10B9A56BC34DEFAB9A8721D" xlink:to="lab_us-gaap_EquityFundsMember_726A7807B10B9A56BC34DEFAB9A8721D" xlink:type="arc" />
    <link:label id="lab_us-gaap_HedgeFundsEquityMember_18C6F0DF334AEB4ECF82DEFAB9A84E21_terseLabel_en-US" xlink:label="lab_us-gaap_HedgeFundsEquityMember_18C6F0DF334AEB4ECF82DEFAB9A84E21" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Long/short equity hedge funds</link:label>
    <link:label id="lab_us-gaap_HedgeFundsEquityMember_18C6F0DF334AEB4ECF82DEFAB9A84E21_label_en-US" xlink:label="lab_us-gaap_HedgeFundsEquityMember_18C6F0DF334AEB4ECF82DEFAB9A84E21" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Hedge Funds, Equity [Member]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_HedgeFundsEquityMember" xlink:label="loc_us-gaap_HedgeFundsEquityMember_18C6F0DF334AEB4ECF82DEFAB9A84E21" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_HedgeFundsEquityMember_18C6F0DF334AEB4ECF82DEFAB9A84E21" xlink:to="lab_us-gaap_HedgeFundsEquityMember_18C6F0DF334AEB4ECF82DEFAB9A84E21" xlink:type="arc" />
    <link:label id="lab_us-gaap_PrivateEquityFundsMember_3FABB18F2E5800A17539DEFAB9A87D1C_terseLabel_en-US" xlink:label="lab_us-gaap_PrivateEquityFundsMember_3FABB18F2E5800A17539DEFAB9A87D1C" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Private equity</link:label>
    <link:label id="lab_us-gaap_PrivateEquityFundsMember_3FABB18F2E5800A17539DEFAB9A87D1C_label_en-US" xlink:label="lab_us-gaap_PrivateEquityFundsMember_3FABB18F2E5800A17539DEFAB9A87D1C" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Private Equity Funds [Member]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PrivateEquityFundsMember" xlink:label="loc_us-gaap_PrivateEquityFundsMember_3FABB18F2E5800A17539DEFAB9A87D1C" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PrivateEquityFundsMember_3FABB18F2E5800A17539DEFAB9A87D1C" xlink:to="lab_us-gaap_PrivateEquityFundsMember_3FABB18F2E5800A17539DEFAB9A87D1C" xlink:type="arc" />
    <link:label id="lab_arnc_IntermediateAndLongDurationGovernmentCreditMember_023FFB494EF215FE047DDEFAB9A8EA53_terseLabel_en-US" xlink:label="lab_arnc_IntermediateAndLongDurationGovernmentCreditMember_023FFB494EF215FE047DDEFAB9A8EA53" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Intermediate and long duration government/credit</link:label>
    <link:label id="lab_arnc_IntermediateAndLongDurationGovernmentCreditMember_023FFB494EF215FE047DDEFAB9A8EA53_label_en-US" xlink:label="lab_arnc_IntermediateAndLongDurationGovernmentCreditMember_023FFB494EF215FE047DDEFAB9A8EA53" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Intermediate and Long Duration Government Credit [Member]</link:label>
    <link:label id="lab_arnc_IntermediateAndLongDurationGovernmentCreditMember_023FFB494EF215FE047DDEFAB9A8EA53_documentation_en-US" xlink:label="lab_arnc_IntermediateAndLongDurationGovernmentCreditMember_023FFB494EF215FE047DDEFAB9A8EA53" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Intermediate and Long Duration Government Credit [Member]</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_IntermediateAndLongDurationGovernmentCreditMember" xlink:label="loc_arnc_IntermediateAndLongDurationGovernmentCreditMember_023FFB494EF215FE047DDEFAB9A8EA53" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_IntermediateAndLongDurationGovernmentCreditMember_023FFB494EF215FE047DDEFAB9A8EA53" xlink:to="lab_arnc_IntermediateAndLongDurationGovernmentCreditMember_023FFB494EF215FE047DDEFAB9A8EA53" xlink:type="arc" />
    <link:label id="lab_arnc_OtherFundsMember_F7407615E29A04C67AF8DEFAB9A9179B_terseLabel_en-US" xlink:label="lab_arnc_OtherFundsMember_F7407615E29A04C67AF8DEFAB9A9179B" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Other</link:label>
    <link:label id="lab_arnc_OtherFundsMember_F7407615E29A04C67AF8DEFAB9A9179B_label_en-US" xlink:label="lab_arnc_OtherFundsMember_F7407615E29A04C67AF8DEFAB9A9179B" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Other Funds [Member]</link:label>
    <link:label id="lab_arnc_OtherFundsMember_F7407615E29A04C67AF8DEFAB9A9179B_documentation_en-US" xlink:label="lab_arnc_OtherFundsMember_F7407615E29A04C67AF8DEFAB9A9179B" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Other Funds [Member]</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_OtherFundsMember" xlink:label="loc_arnc_OtherFundsMember_F7407615E29A04C67AF8DEFAB9A9179B" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_OtherFundsMember_F7407615E29A04C67AF8DEFAB9A9179B" xlink:to="lab_arnc_OtherFundsMember_F7407615E29A04C67AF8DEFAB9A9179B" xlink:type="arc" />
    <link:label id="lab_us-gaap_RealEstateFundsMember_BD29646413FD229F2526DEFAB9A9F56B_terseLabel_en-US" xlink:label="lab_us-gaap_RealEstateFundsMember_BD29646413FD229F2526DEFAB9A9F56B" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Real estate</link:label>
    <link:label id="lab_us-gaap_RealEstateFundsMember_BD29646413FD229F2526DEFAB9A9F56B_label_en-US" xlink:label="lab_us-gaap_RealEstateFundsMember_BD29646413FD229F2526DEFAB9A9F56B" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Real Estate Funds [Member]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RealEstateFundsMember" xlink:label="loc_us-gaap_RealEstateFundsMember_BD29646413FD229F2526DEFAB9A9F56B" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RealEstateFundsMember_BD29646413FD229F2526DEFAB9A9F56B" xlink:to="lab_us-gaap_RealEstateFundsMember_BD29646413FD229F2526DEFAB9A9F56B" xlink:type="arc" />
    <link:label id="lab_arnc_DiscretionaryAndSystematicMacroHedgeFundsMember_888BB5378CD640E6FB8DDEFAB9A95664_terseLabel_en-US" xlink:label="lab_arnc_DiscretionaryAndSystematicMacroHedgeFundsMember_888BB5378CD640E6FB8DDEFAB9A95664" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Discretionary and systematic macro hedge funds</link:label>
    <link:label id="lab_arnc_DiscretionaryAndSystematicMacroHedgeFundsMember_888BB5378CD640E6FB8DDEFAB9A95664_label_en-US" xlink:label="lab_arnc_DiscretionaryAndSystematicMacroHedgeFundsMember_888BB5378CD640E6FB8DDEFAB9A95664" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Discretionary And Systematic Macro Hedge Funds [Member]</link:label>
    <link:label id="lab_arnc_DiscretionaryAndSystematicMacroHedgeFundsMember_888BB5378CD640E6FB8DDEFAB9A95664_documentation_en-US" xlink:label="lab_arnc_DiscretionaryAndSystematicMacroHedgeFundsMember_888BB5378CD640E6FB8DDEFAB9A95664" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Discretionary and systematic macro hedge funds.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_DiscretionaryAndSystematicMacroHedgeFundsMember" xlink:label="loc_arnc_DiscretionaryAndSystematicMacroHedgeFundsMember_888BB5378CD640E6FB8DDEFAB9A95664" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_DiscretionaryAndSystematicMacroHedgeFundsMember_888BB5378CD640E6FB8DDEFAB9A95664" xlink:to="lab_arnc_DiscretionaryAndSystematicMacroHedgeFundsMember_888BB5378CD640E6FB8DDEFAB9A95664" xlink:type="arc" />
    <link:label id="lab_us-gaap_DefinedBenefitPlanFairValueOfPlanAssets_1E1BADA3C4C5D102A437DEFAB9A9955C_terseLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanFairValueOfPlanAssets_1E1BADA3C4C5D102A437DEFAB9A9955C" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Fair value of pension and other postretirement plans' assets</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DefinedBenefitPlanFairValueOfPlanAssets" xlink:label="loc_us-gaap_DefinedBenefitPlanFairValueOfPlanAssets_1E1BADA3C4C5D102A437DEFAB9A9955C" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanFairValueOfPlanAssets_1E1BADA3C4C5D102A437DEFAB9A9955C" xlink:to="lab_us-gaap_DefinedBenefitPlanFairValueOfPlanAssets_1E1BADA3C4C5D102A437DEFAB9A9955C" xlink:type="arc" />
    <link:label id="lab_arnc_DefinedBenefitPlanAlternativeInvestmentsFairValueOfPlanAsset_9D7076808F165D08BC25DEFAB9A90022_terseLabel_en-US" xlink:label="lab_arnc_DefinedBenefitPlanAlternativeInvestmentsFairValueOfPlanAsset_9D7076808F165D08BC25DEFAB9A90022" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Defined benefit plan, alternative investments, fair value of plan asset</link:label>
    <link:label id="lab_arnc_DefinedBenefitPlanAlternativeInvestmentsFairValueOfPlanAsset_9D7076808F165D08BC25DEFAB9A90022_label_en-US" xlink:label="lab_arnc_DefinedBenefitPlanAlternativeInvestmentsFairValueOfPlanAsset_9D7076808F165D08BC25DEFAB9A90022" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Alternative Investments, Fair Value Of Plan Asset</link:label>
    <link:label id="lab_arnc_DefinedBenefitPlanAlternativeInvestmentsFairValueOfPlanAsset_9D7076808F165D08BC25DEFAB9A90022_documentation_en-US" xlink:label="lab_arnc_DefinedBenefitPlanAlternativeInvestmentsFairValueOfPlanAsset_9D7076808F165D08BC25DEFAB9A90022" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Alternative Investments, Fair Value Of Plan Asset</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_DefinedBenefitPlanAlternativeInvestmentsFairValueOfPlanAsset" xlink:label="loc_arnc_DefinedBenefitPlanAlternativeInvestmentsFairValueOfPlanAsset_9D7076808F165D08BC25DEFAB9A90022" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_DefinedBenefitPlanAlternativeInvestmentsFairValueOfPlanAsset_9D7076808F165D08BC25DEFAB9A90022" xlink:to="lab_arnc_DefinedBenefitPlanAlternativeInvestmentsFairValueOfPlanAsset_9D7076808F165D08BC25DEFAB9A90022" xlink:type="arc" />
    <link:label id="lab_arnc_ReceivablesExcludedFromPensionPlanAssets_5AF490C0E40C24DAC265DEFAB9AA95B1_terseLabel_en-US" xlink:label="lab_arnc_ReceivablesExcludedFromPensionPlanAssets_5AF490C0E40C24DAC265DEFAB9AA95B1" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Net receivables which represents assets related to divested businesses to be transferred to the buyers</link:label>
    <link:label id="lab_arnc_ReceivablesExcludedFromPensionPlanAssets_5AF490C0E40C24DAC265DEFAB9AA95B1_label_en-US" xlink:label="lab_arnc_ReceivablesExcludedFromPensionPlanAssets_5AF490C0E40C24DAC265DEFAB9AA95B1" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Receivables Excluded From Pension Plan Assets</link:label>
    <link:label id="lab_arnc_ReceivablesExcludedFromPensionPlanAssets_5AF490C0E40C24DAC265DEFAB9AA95B1_documentation_en-US" xlink:label="lab_arnc_ReceivablesExcludedFromPensionPlanAssets_5AF490C0E40C24DAC265DEFAB9AA95B1" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Receivables excluded from pension plan assets.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_ReceivablesExcludedFromPensionPlanAssets" xlink:label="loc_arnc_ReceivablesExcludedFromPensionPlanAssets_5AF490C0E40C24DAC265DEFAB9AA95B1" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_ReceivablesExcludedFromPensionPlanAssets_5AF490C0E40C24DAC265DEFAB9AA95B1" xlink:to="lab_arnc_ReceivablesExcludedFromPensionPlanAssets_5AF490C0E40C24DAC265DEFAB9AA95B1" xlink:type="arc" />
    <link:label id="lab_arnc_DefinedBenefitPlanPlanAssetsAmountExcludingNetReceivablesFromCertainSources_2D02F4336AA372B5C748DF275554BF0E_terseLabel_en-US" xlink:label="lab_arnc_DefinedBenefitPlanPlanAssetsAmountExcludingNetReceivablesFromCertainSources_2D02F4336AA372B5C748DF275554BF0E" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Net plan assets, excluding net receivables from securities purchased and sold but not yet settled plus interest and dividends earned on various investments</link:label>
    <link:label id="lab_arnc_DefinedBenefitPlanPlanAssetsAmountExcludingNetReceivablesFromCertainSources_2D02F4336AA372B5C748DF275554BF0E_label_en-US" xlink:label="lab_arnc_DefinedBenefitPlanPlanAssetsAmountExcludingNetReceivablesFromCertainSources_2D02F4336AA372B5C748DF275554BF0E" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Plan Assets, Amount Excluding Net Receivables From Certain Sources</link:label>
    <link:label id="lab_arnc_DefinedBenefitPlanPlanAssetsAmountExcludingNetReceivablesFromCertainSources_2D02F4336AA372B5C748DF275554BF0E_documentation_en-US" xlink:label="lab_arnc_DefinedBenefitPlanPlanAssetsAmountExcludingNetReceivablesFromCertainSources_2D02F4336AA372B5C748DF275554BF0E" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Plan Assets, Amount Excluding Net Receivables From Certain Sources</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_DefinedBenefitPlanPlanAssetsAmountExcludingNetReceivablesFromCertainSources" xlink:label="loc_arnc_DefinedBenefitPlanPlanAssetsAmountExcludingNetReceivablesFromCertainSources_2D02F4336AA372B5C748DF275554BF0E" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_DefinedBenefitPlanPlanAssetsAmountExcludingNetReceivablesFromCertainSources_2D02F4336AA372B5C748DF275554BF0E" xlink:to="lab_arnc_DefinedBenefitPlanPlanAssetsAmountExcludingNetReceivablesFromCertainSources_2D02F4336AA372B5C748DF275554BF0E" xlink:type="arc" />
    <link:label id="lab_arnc_DefinedBenefitPlanPlanAssetsAmountExcludingCertainNetReceivables_1D14DECFD3F02F8F8B8DDF294571DCB6_terseLabel_en-US" xlink:label="lab_arnc_DefinedBenefitPlanPlanAssetsAmountExcludingCertainNetReceivables_1D14DECFD3F02F8F8B8DDF294571DCB6" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Net plan assets excluding certain net receivables</link:label>
    <link:label id="lab_arnc_DefinedBenefitPlanPlanAssetsAmountExcludingCertainNetReceivables_1D14DECFD3F02F8F8B8DDF294571DCB6_label_en-US" xlink:label="lab_arnc_DefinedBenefitPlanPlanAssetsAmountExcludingCertainNetReceivables_1D14DECFD3F02F8F8B8DDF294571DCB6" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Plan Assets, Amount Excluding Certain Net Receivables</link:label>
    <link:label id="lab_arnc_DefinedBenefitPlanPlanAssetsAmountExcludingCertainNetReceivables_1D14DECFD3F02F8F8B8DDF294571DCB6_documentation_en-US" xlink:label="lab_arnc_DefinedBenefitPlanPlanAssetsAmountExcludingCertainNetReceivables_1D14DECFD3F02F8F8B8DDF294571DCB6" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Plan Assets, Amount Excluding Certain Net Receivables</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_DefinedBenefitPlanPlanAssetsAmountExcludingCertainNetReceivables" xlink:label="loc_arnc_DefinedBenefitPlanPlanAssetsAmountExcludingCertainNetReceivables_1D14DECFD3F02F8F8B8DDF294571DCB6" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_DefinedBenefitPlanPlanAssetsAmountExcludingCertainNetReceivables_1D14DECFD3F02F8F8B8DDF294571DCB6" xlink:to="lab_arnc_DefinedBenefitPlanPlanAssetsAmountExcludingCertainNetReceivables_1D14DECFD3F02F8F8B8DDF294571DCB6" xlink:type="arc" />
    <link:label id="lab_us-gaap_SubsequentEventsTextBlock_570BE4F0E04AB1FE236BE244A896E16E_terseLabel_en-US" xlink:label="lab_us-gaap_SubsequentEventsTextBlock_570BE4F0E04AB1FE236BE244A896E16E" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Subsequent Events</link:label>
    <link:label id="lab_us-gaap_SubsequentEventsTextBlock_570BE4F0E04AB1FE236BE244A896E16E_label_en-US" xlink:label="lab_us-gaap_SubsequentEventsTextBlock_570BE4F0E04AB1FE236BE244A896E16E" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Subsequent Events [Text Block]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_SubsequentEventsTextBlock" xlink:label="loc_us-gaap_SubsequentEventsTextBlock_570BE4F0E04AB1FE236BE244A896E16E" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SubsequentEventsTextBlock_570BE4F0E04AB1FE236BE244A896E16E" xlink:to="lab_us-gaap_SubsequentEventsTextBlock_570BE4F0E04AB1FE236BE244A896E16E" xlink:type="arc" />
    <link:label id="lab_us-gaap_ScheduleOfDebtTableTextBlock_838F78D20084BDC8A83DE244A99A5DEF_terseLabel_en-US" xlink:label="lab_us-gaap_ScheduleOfDebtTableTextBlock_838F78D20084BDC8A83DE244A99A5DEF" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Schedule of Long-Term Debt</link:label>
    <link:label id="lab_us-gaap_ScheduleOfDebtTableTextBlock_838F78D20084BDC8A83DE244A99A5DEF_label_en-US" xlink:label="lab_us-gaap_ScheduleOfDebtTableTextBlock_838F78D20084BDC8A83DE244A99A5DEF" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Schedule of Debt [Table Text Block]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ScheduleOfDebtTableTextBlock" xlink:label="loc_us-gaap_ScheduleOfDebtTableTextBlock_838F78D20084BDC8A83DE244A99A5DEF" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfDebtTableTextBlock_838F78D20084BDC8A83DE244A99A5DEF" xlink:to="lab_us-gaap_ScheduleOfDebtTableTextBlock_838F78D20084BDC8A83DE244A99A5DEF" xlink:type="arc" />
    <link:label id="lab_us-gaap_ScheduleOfIncomeBeforeIncomeTaxDomesticAndForeignTableTextBlock_9EF2F05AE08A97599A447C362EA9C244_terseLabel_en-US" xlink:label="lab_us-gaap_ScheduleOfIncomeBeforeIncomeTaxDomesticAndForeignTableTextBlock_9EF2F05AE08A97599A447C362EA9C244" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Components of Income from Continuing Operations Before Income Taxes</link:label>
    <link:label id="lab_us-gaap_ScheduleOfIncomeBeforeIncomeTaxDomesticAndForeignTableTextBlock_9EF2F05AE08A97599A447C362EA9C244_label_en-US" xlink:label="lab_us-gaap_ScheduleOfIncomeBeforeIncomeTaxDomesticAndForeignTableTextBlock_9EF2F05AE08A97599A447C362EA9C244" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Schedule of Income before Income Tax, Domestic and Foreign [Table Text Block]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ScheduleOfIncomeBeforeIncomeTaxDomesticAndForeignTableTextBlock" xlink:label="loc_us-gaap_ScheduleOfIncomeBeforeIncomeTaxDomesticAndForeignTableTextBlock_9EF2F05AE08A97599A447C362EA9C244" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfIncomeBeforeIncomeTaxDomesticAndForeignTableTextBlock_9EF2F05AE08A97599A447C362EA9C244" xlink:to="lab_us-gaap_ScheduleOfIncomeBeforeIncomeTaxDomesticAndForeignTableTextBlock_9EF2F05AE08A97599A447C362EA9C244" xlink:type="arc" />
    <link:label id="lab_us-gaap_ScheduleOfComponentsOfIncomeTaxExpenseBenefitTableTextBlock_F4E9B6D0AE8AB4BCE4E87C362EA95B84_terseLabel_en-US" xlink:label="lab_us-gaap_ScheduleOfComponentsOfIncomeTaxExpenseBenefitTableTextBlock_F4E9B6D0AE8AB4BCE4E87C362EA95B84" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Schedule of Provision for Income Taxes on Income from Continuing Operations</link:label>
    <link:label id="lab_us-gaap_ScheduleOfComponentsOfIncomeTaxExpenseBenefitTableTextBlock_F4E9B6D0AE8AB4BCE4E87C362EA95B84_label_en-US" xlink:label="lab_us-gaap_ScheduleOfComponentsOfIncomeTaxExpenseBenefitTableTextBlock_F4E9B6D0AE8AB4BCE4E87C362EA95B84" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Schedule of Components of Income Tax Expense (Benefit) [Table Text Block]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ScheduleOfComponentsOfIncomeTaxExpenseBenefitTableTextBlock" xlink:label="loc_us-gaap_ScheduleOfComponentsOfIncomeTaxExpenseBenefitTableTextBlock_F4E9B6D0AE8AB4BCE4E87C362EA95B84" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfComponentsOfIncomeTaxExpenseBenefitTableTextBlock_F4E9B6D0AE8AB4BCE4E87C362EA95B84" xlink:to="lab_us-gaap_ScheduleOfComponentsOfIncomeTaxExpenseBenefitTableTextBlock_F4E9B6D0AE8AB4BCE4E87C362EA95B84" xlink:type="arc" />
    <link:label id="lab_us-gaap_ScheduleOfEffectiveIncomeTaxRateReconciliationTableTextBlock_BBC355A4293228B904307C362EA99522_terseLabel_en-US" xlink:label="lab_us-gaap_ScheduleOfEffectiveIncomeTaxRateReconciliationTableTextBlock_BBC355A4293228B904307C362EA99522" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Reconciliation of U.S. Federal Statutory Rate to Arconic's Effective Tax Rate</link:label>
    <link:label id="lab_us-gaap_ScheduleOfEffectiveIncomeTaxRateReconciliationTableTextBlock_BBC355A4293228B904307C362EA99522_label_en-US" xlink:label="lab_us-gaap_ScheduleOfEffectiveIncomeTaxRateReconciliationTableTextBlock_BBC355A4293228B904307C362EA99522" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Schedule of Effective Income Tax Rate Reconciliation [Table Text Block]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ScheduleOfEffectiveIncomeTaxRateReconciliationTableTextBlock" xlink:label="loc_us-gaap_ScheduleOfEffectiveIncomeTaxRateReconciliationTableTextBlock_BBC355A4293228B904307C362EA99522" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfEffectiveIncomeTaxRateReconciliationTableTextBlock_BBC355A4293228B904307C362EA99522" xlink:to="lab_us-gaap_ScheduleOfEffectiveIncomeTaxRateReconciliationTableTextBlock_BBC355A4293228B904307C362EA99522" xlink:type="arc" />
    <link:label id="lab_us-gaap_ScheduleOfDeferredTaxAssetsAndLiabilitiesTableTextBlock_F11968C968C6B9CB2CD37C362EA9900D_terseLabel_en-US" xlink:label="lab_us-gaap_ScheduleOfDeferredTaxAssetsAndLiabilitiesTableTextBlock_F11968C968C6B9CB2CD37C362EA9900D" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Schedule of Components of Net Deferred Tax Assets and Liabilities</link:label>
    <link:label id="lab_us-gaap_ScheduleOfDeferredTaxAssetsAndLiabilitiesTableTextBlock_F11968C968C6B9CB2CD37C362EA9900D_label_en-US" xlink:label="lab_us-gaap_ScheduleOfDeferredTaxAssetsAndLiabilitiesTableTextBlock_F11968C968C6B9CB2CD37C362EA9900D" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Schedule of Deferred Tax Assets and Liabilities [Table Text Block]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ScheduleOfDeferredTaxAssetsAndLiabilitiesTableTextBlock" xlink:label="loc_us-gaap_ScheduleOfDeferredTaxAssetsAndLiabilitiesTableTextBlock_F11968C968C6B9CB2CD37C362EA9900D" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfDeferredTaxAssetsAndLiabilitiesTableTextBlock_F11968C968C6B9CB2CD37C362EA9900D" xlink:to="lab_us-gaap_ScheduleOfDeferredTaxAssetsAndLiabilitiesTableTextBlock_F11968C968C6B9CB2CD37C362EA9900D" xlink:type="arc" />
    <link:label id="lab_arnc_ScheduleOfExpirationPeriodsOfDeferredTaxAssetsTableTextBlock_D65795CECDCC0073C9A87C362EA90B86_terseLabel_en-US" xlink:label="lab_arnc_ScheduleOfExpirationPeriodsOfDeferredTaxAssetsTableTextBlock_D65795CECDCC0073C9A87C362EA90B86" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Schedule of Expiration Periods of Deferred Tax Assets</link:label>
    <link:label id="lab_arnc_ScheduleOfExpirationPeriodsOfDeferredTaxAssetsTableTextBlock_D65795CECDCC0073C9A87C362EA90B86_label_en-US" xlink:label="lab_arnc_ScheduleOfExpirationPeriodsOfDeferredTaxAssetsTableTextBlock_D65795CECDCC0073C9A87C362EA90B86" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Schedule Of Expiration Periods Of Deferred Tax Assets [Table Text Block]</link:label>
    <link:label id="lab_arnc_ScheduleOfExpirationPeriodsOfDeferredTaxAssetsTableTextBlock_D65795CECDCC0073C9A87C362EA90B86_documentation_en-US" xlink:label="lab_arnc_ScheduleOfExpirationPeriodsOfDeferredTaxAssetsTableTextBlock_D65795CECDCC0073C9A87C362EA90B86" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Schedule of expiration periods of deferred tax assets.</link:label>
    <link:loc xlink:href="arnc-20181231.xsd#arnc_ScheduleOfExpirationPeriodsOfDeferredTaxAssetsTableTextBlock" xlink:label="loc_arnc_ScheduleOfExpirationPeriodsOfDeferredTaxAssetsTableTextBlock_D65795CECDCC0073C9A87C362EA90B86" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_arnc_ScheduleOfExpirationPeriodsOfDeferredTaxAssetsTableTextBlock_D65795CECDCC0073C9A87C362EA90B86" xlink:to="lab_arnc_ScheduleOfExpirationPeriodsOfDeferredTaxAssetsTableTextBlock_D65795CECDCC0073C9A87C362EA90B86" xlink:type="arc" />
    <link:label id="lab_us-gaap_SummaryOfValuationAllowanceTextBlock_197A4DE83C29A58BBFC67C362EA9F848_terseLabel_en-US" xlink:label="lab_us-gaap_SummaryOfValuationAllowanceTextBlock_197A4DE83C29A58BBFC67C362EA9F848" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Schedule of Changes in Valuation Allowance</link:label>
    <link:label id="lab_us-gaap_SummaryOfValuationAllowanceTextBlock_197A4DE83C29A58BBFC67C362EA9F848_label_en-US" xlink:label="lab_us-gaap_SummaryOfValuationAllowanceTextBlock_197A4DE83C29A58BBFC67C362EA9F848" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Summary of Valuation Allowance [Table Text Block]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_SummaryOfValuationAllowanceTextBlock" xlink:label="loc_us-gaap_SummaryOfValuationAllowanceTextBlock_197A4DE83C29A58BBFC67C362EA9F848" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SummaryOfValuationAllowanceTextBlock_197A4DE83C29A58BBFC67C362EA9F848" xlink:to="lab_us-gaap_SummaryOfValuationAllowanceTextBlock_197A4DE83C29A58BBFC67C362EA9F848" xlink:type="arc" />
    <link:label id="lab_us-gaap_ScheduleOfUnrecognizedTaxBenefitsRollForwardTableTextBlock_54737649AAE4162F15337C362EA9CC02_terseLabel_en-US" xlink:label="lab_us-gaap_ScheduleOfUnrecognizedTaxBenefitsRollForwardTableTextBlock_54737649AAE4162F15337C362EA9CC02" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Reconciliation of Unrecognized Tax Benefits (Excluding Interest and Penalties)</link:label>
    <link:label id="lab_us-gaap_ScheduleOfUnrecognizedTaxBenefitsRollForwardTableTextBlock_54737649AAE4162F15337C362EA9CC02_label_en-US" xlink:label="lab_us-gaap_ScheduleOfUnrecognizedTaxBenefitsRollForwardTableTextBlock_54737649AAE4162F15337C362EA9CC02" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Schedule of Unrecognized Tax Benefits Roll Forward [Table Text Block]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ScheduleOfUnrecognizedTaxBenefitsRollForwardTableTextBlock" xlink:label="loc_us-gaap_ScheduleOfUnrecognizedTaxBenefitsRollForwardTableTextBlock_54737649AAE4162F15337C362EA9CC02" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfUnrecognizedTaxBenefitsRollForwardTableTextBlock_54737649AAE4162F15337C362EA9CC02" xlink:to="lab_us-gaap_ScheduleOfUnrecognizedTaxBenefitsRollForwardTableTextBlock_54737649AAE4162F15337C362EA9CC02" xlink:type="arc" />
    <link:label id="lab_us-gaap_CommonStockDividendsPerShareDeclared_2FF4CD4DB979C115A1FBBA4BBF136042_terseLabel_en-US" xlink:label="lab_us-gaap_CommonStockDividendsPerShareDeclared_2FF4CD4DB979C115A1FBBA4BBF136042" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Common stock, dividends declared per share (usd per share)</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_CommonStockDividendsPerShareDeclared" xlink:label="loc_us-gaap_CommonStockDividendsPerShareDeclared_2FF4CD4DB979C115A1FBBA4BBF136042" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CommonStockDividendsPerShareDeclared_2FF4CD4DB979C115A1FBBA4BBF136042" xlink:to="lab_us-gaap_CommonStockDividendsPerShareDeclared_2FF4CD4DB979C115A1FBBA4BBF136042" xlink:type="arc" />
    <link:label id="lab_us-gaap_PreferredStockDividendsPerShareDeclared_016C24CDA308A000D43DBA4BBF132CDF_verboseLabel_en-US" xlink:label="lab_us-gaap_PreferredStockDividendsPerShareDeclared_016C24CDA308A000D43DBA4BBF132CDF" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Preferred, dividends per share (usd per share)</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PreferredStockDividendsPerShareDeclared" xlink:label="loc_us-gaap_PreferredStockDividendsPerShareDeclared_016C24CDA308A000D43DBA4BBF132CDF" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PreferredStockDividendsPerShareDeclared_016C24CDA308A000D43DBA4BBF132CDF" xlink:to="lab_us-gaap_PreferredStockDividendsPerShareDeclared_016C24CDA308A000D43DBA4BBF132CDF" xlink:type="arc" />
    <link:label id="lab_us-gaap_PropertyPlantAndEquipmentTextBlock_F4E894FBADFAB3DF83EDE244A9CA523E_terseLabel_en-US" xlink:label="lab_us-gaap_PropertyPlantAndEquipmentTextBlock_F4E894FBADFAB3DF83EDE244A9CA523E" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Schedule of Properties, Plants, and Equipment, Net</link:label>
    <link:label id="lab_us-gaap_PropertyPlantAndEquipmentTextBlock_F4E894FBADFAB3DF83EDE244A9CA523E_label_en-US" xlink:label="lab_us-gaap_PropertyPlantAndEquipmentTextBlock_F4E894FBADFAB3DF83EDE244A9CA523E" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Property, Plant and Equipment [Table Text Block]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PropertyPlantAndEquipmentTextBlock" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentTextBlock_F4E894FBADFAB3DF83EDE244A9CA523E" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentTextBlock_F4E894FBADFAB3DF83EDE244A9CA523E" xlink:to="lab_us-gaap_PropertyPlantAndEquipmentTextBlock_F4E894FBADFAB3DF83EDE244A9CA523E" xlink:type="arc" />
  </link:labelLink>
</link:linkbase>
