<SUBMISSION>
<ACCESSION-NUMBER>0001790982-20-000075
<TYPE>3/A
<PUBLIC-DOCUMENT-COUNT>1
<PERIOD>20200401
<FILING-DATE>20200410
<DATE-OF-FILING-DATE-CHANGE>20200410
<REPORTING-OWNER>
<OWNER-DATA>
<CONFORMED-NAME>Henderson Frederick A.
<CIK>0001181685
</OWNER-DATA>
<FILING-VALUES>
<FORM-TYPE>3/A
<ACT>34
<FILE-NUMBER>001-39162
<FILM-NUMBER>20787607
</FILING-VALUES>
<MAIL-ADDRESS>
<STREET1>SUNCOKE ENERGY, INC.
<STREET2>1011 WARRENVILLE ROAD, SUITE 600
<CITY>LISLE
<STATE>IL
<ZIP>60532
</MAIL-ADDRESS>
<FORMER-NAME>
<FORMER-CONFORMED-NAME>HENDERSON FREDERICK A
<DATE-CHANGED>20020821
</FORMER-NAME>
</REPORTING-OWNER>
<ISSUER>
<COMPANY-DATA>
<CONFORMED-NAME>Arconic Corp
<CIK>0001790982
<ASSIGNED-SIC>3350
<IRS-NUMBER>842745636
<STATE-OF-INCORPORATION>DE
<FISCAL-YEAR-END>1231
</COMPANY-DATA>
<BUSINESS-ADDRESS>
<STREET1>201 ISABELLA STREET
<CITY>PITTSBURGH
<STATE>PA
<ZIP>15212-5872
<PHONE>(412) 992-2500
</BUSINESS-ADDRESS>
<MAIL-ADDRESS>
<STREET1>201 ISABELLA STREET
<CITY>PITTSBURGH
<STATE>PA
<ZIP>15212-5872
</MAIL-ADDRESS>
<FORMER-COMPANY>
<FORMER-CONFORMED-NAME>Arconic Rolled Products Corp
<DATE-CHANGED>20191011
</FORMER-COMPANY>
</ISSUER>
<DOCUMENT>
<TYPE>3/A
<SEQUENCE>1
<FILENAME>edgar.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0206</schemaVersion>

    <documentType>3/A</documentType>

    <periodOfReport>2020-04-01</periodOfReport>

    <dateOfOriginalSubmission>2020-04-01</dateOfOriginalSubmission>

    <noSecuritiesOwned>0</noSecuritiesOwned>

    <issuer>
        <issuerCik>0001790982</issuerCik>
        <issuerName>Arconic Corp</issuerName>
        <issuerTradingSymbol>ARNC</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001181685</rptOwnerCik>
            <rptOwnerName>Henderson Frederick A.</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>201 ISABELLA STREET</rptOwnerStreet1>
            <rptOwnerStreet2>SUITE 200</rptOwnerStreet2>
            <rptOwnerCity>PITTSBURGH,</rptOwnerCity>
            <rptOwnerState>PA</rptOwnerState>
            <rptOwnerZipCode>15212-5872</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle></officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>7</value>
                    <footnoteId id="F1"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
    </nonDerivativeTable>

    <derivativeTable></derivativeTable>

    <footnotes>
        <footnote id="F1">This amendment includes shares of common stock that were distributed in respect of Arconic Inc. shares held in an S&amp;P stock index fund that were inadvertently omitted from the Form 3 filing by Frederick Henderson on April 1, 2020.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Diana Toman (CLO and Secretary), by power of attorney</signatureName>
        <signatureDate>2020-04-10</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SUBMISSION>
