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  <xsd:element abstract="true" id="ati_NickelAndOtherRawMaterialContractsMember" name="NickelAndOtherRawMaterialContractsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ati_NickelMember" name="NickelMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ati_NickelbasedAlloysandSpecialtyAlloysMember" name="NickelbasedAlloysandSpecialtyAlloysMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="ati_Nonoperatingretirementbenefitexpense" name="Nonoperatingretirementbenefitexpense" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ati_OilandGasMarketMember" name="OilandGasMarketMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="ati_OtherComprehensiveIncomeLossBeforeReclassificationAdjustmentsNetOfTaxAttributableToNoncontrollingInterest" name="OtherComprehensiveIncomeLossBeforeReclassificationAdjustmentsNetOfTaxAttributableToNoncontrollingInterest" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="ati_OtherComprehensiveIncomeLossbeforeReclassificationsNetofTaxAttributabletoNoncontrollingInterest" name="OtherComprehensiveIncomeLossbeforeReclassificationsNetofTaxAttributabletoNoncontrollingInterest" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="ati_OtherExpense" name="OtherExpense" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ati_OtherMarketMember" name="OtherMarketMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="ati_PercentageOfForecastedNaturalGasUsageHedgedforYear1" name="PercentageOfForecastedNaturalGasUsageHedgedforYear1" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration" />
  <xsd:element id="ati_PercentageOfForecastedNaturalGasUsageHedgedforYear2" name="PercentageOfForecastedNaturalGasUsageHedgedforYear2" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration" />
  <xsd:element id="ati_PercentageOfRawMaterialUsageHedged" name="PercentageOfRawMaterialUsageHedged" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration" />
  <xsd:element id="ati_Percentageofforecastednaturalusagehedgedyear3" name="Percentageofforecastednaturalusagehedgedyear3" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ati_PrecisionForgingsCastingandComponentsMember" name="PrecisionForgingsCastingandComponentsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ati_PrecisionandEngineeredStripMember" name="PrecisionandEngineeredStripMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="ati_ProceedsPaymentsfromIntercompanyActivitesInvestingActivities" name="ProceedsPaymentsfromIntercompanyActivitesInvestingActivities" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="ati_ReclassificationfromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetofTaxAttributabletoNoncontrollingInterest" name="ReclassificationfromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetofTaxAttributabletoNoncontrollingInterest" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element id="ati_ReclassificationfromAccumulatedOtherComprehensiveIncomeLossCurrentPeriodNetofTaxAttributabletoNoncontrollingInterest" name="ReclassificationfromAccumulatedOtherComprehensiveIncomeLossCurrentPeriodNetofTaxAttributabletoNoncontrollingInterest" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element id="ati_RevenueRemainingPerformanceObligationCurrent" name="RevenueRemainingPerformanceObligationCurrent" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant" />
  <xsd:element id="ati_RevenuefromContractwithCustomerExcludingAssessedTaxPercentageofRevenue" name="RevenuefromContractwithCustomerExcludingAssessedTaxPercentageofRevenue" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration" />
  <xsd:element id="ati_RevenuefromContractwithCustomerPolicyTextBlock" name="RevenuefromContractwithCustomerPolicyTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration" />
  <xsd:element id="ati_ScheduleofInventoryValuationImpactonIncomeTableTextBlock" name="ScheduleofInventoryValuationImpactonIncomeTableTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration" />
  <xsd:element id="ati_SegmentOperatingProfitLoss" name="SegmentOperatingProfitLoss" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ati_ShanghaiStalPrecisionStainlessSteelCoLtdMember" name="ShanghaiStalPrecisionStainlessSteelCoLtdMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ati_SouthAmericaMiddleEastandOtherMember" name="SouthAmericaMiddleEastandOtherMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ati_SpecialtyStainlessSteelSheetsMember" name="SpecialtyStainlessSteelSheetsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ati_StainlessSteelPlatesandOtherMember" name="StainlessSteelPlatesandOtherMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ati_StainlessSteelSheetsMember" name="StainlessSteelSheetsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ati_StandardProductsMember" name="StandardProductsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ati_TitaniumandTitaniumbasedAlloysMember" name="TitaniumandTitaniumbasedAlloysMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="ati_TotalDebt" name="TotalDebt" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant" />
  <xsd:element abstract="true" id="ati_TsingshanGroupMember" name="TsingshanGroupMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ati_UnitiMember" name="UnitiMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ati_VSMPOMember" name="VSMPOMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ati_ZirconiumandRelatedAlloysMember" name="ZirconiumandRelatedAlloysMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
</xsd:schema>
