MIL-DTL--13924D---Black-Oxide

NOTMEASUREMENTSENSITIVEMIL-DTL-13924D18March1999SUPERSEDINGMIL-C-13924C9Junel980DETAILSPECIFICATIONCOATING,OXIDE,BLACK,FORFERROUSMETALSThisspecificationisapprovedforusebyallDepartmentsandAgenciesoftheDepartmentofDefense.1.SCOPE1.1Scope.Thisspecificationcoversblackoxidecoatingsappliedtoferrousmetals(wroughtiron,carbon,lowalloy,andcorrosionresistantsteels).Blackoxidecoatings,withorwithoutasupplementarypreservativetreatment(see3.11),maybeusedwhereablacksurfaceisrequired.Onlyverylimitedcorrosionprotection,undermildlycorrosiveconditions,isobtainedasaresultofblackoxidecoating(see6.1).Blackcoatingsareincludedinthisspecificationwithlimitationsasnotedin1.2.1.2Classification.Blackoxidecoatingscoveredbythisspecificationshouldbeofthefollowingclassesasspecified(see6.2and6.3.2).Class1Alkalineoxidizingprocess(forwroughtiron,castandmalleableirons,plaincarbon,andlowalloysteels).Class2Alkalinechromateoxidizingprocess(foruseoncertaincorrosionresistantsteelalloyswhicharetemperedatlessthan900°F(482°C)).Class3Fusedsaltoxidizingprocess(forcorrosionresistantsteelalloyswhicharetemperedat900°F(482°C)orhigher).Class4Alkalineoxidizingprocess(forothercorrosionresistantsteelalloys).Beneficialcomments(recommendations,additions,deletions)andanypertinentdatawhichmaybeofuseinimprovingthisdocumentshouldbeaddressedto:Director,U.S.ArmyResearchLaboratory,WeaponsandMaterialsResearchDirectorate,ATTN:AMSRL-WM-M,AberdeenProvingGround,MD21005-5069byusingtheStandardizationDocumentImprovementProposal(DDForm1426)appearingattheendofthisdocumentorbyletter.AMSCN/AAREAMFFPMIL-DTL-13924D22.APPLICABLEDOCUMENTS2.1General.Thedocumentslistedinthissectionarespecifiedinsections3and4ofthisspecification.Thissectiondoesnotincludedocumentsinothersectionsofthisspecificationorrecommendedforadditionalinformationorasexamples.Whileeveryefforthasbeenmadetoensurethecompletenessofthislist,documentusersarecautionedthattheymustmeetallspecifiedrequirementsdocumentscitedinsections3and4ofthisspecification,whetherornottheyarelisted.2.2Governmentdocuments.2.2.1Specifications,standards,andhandbooks.Thefollowingspecifications,standards,andhandbooksformapartofthisdocumenttotheextentspecifiedherein.Unlessotherwisespecified,theissuesofthesedocumentsarethoselistedintheissueoftheDepartmentofDefenseIndexofSpecificationsandStandards(DoDISS)andsupplementthereto,citedinthesolicitation(see6.2).SPECIFICATIONSDEPARTMENTOFDEFENSEMIL-C-53072ChemicalAgentResistantCoating(CARC)SystemApplicationProceduresAndQualityControlInspection(Unlessotherwiseindicated,copiesoftheabovespecifications,standards,andhandbooksareavailablefromtheDefenseAutomatedPrintingService(DAPS),Building4D,700RobbinsAvenue,Philadelphia,PA19111-5094).2.3Non-Governmentpublications.Thefollowingdocumentsformapartofthisdocumenttotheextentspecifiedherein.Unlessotherwisespecified,theissuesofthedocumentswhichareDoDadoptedarethoselistedintheissueoftheDoDISScitedinthesolicitation.Unlessotherwisespecified,theissuesofdocumentsnotlistedintheDoDISSaretheissuesofthedocumentscitedinthesolicitation(see6.2).AMERICANSOCIETYFORTESTINGANDMATERIALS(ASTM)ASTMB117OperatingSaltSpray(Fog)Apparatus(DoDadopted)ASTMF519MechanicalHydrogenEmbrittlementTestingofPlatingProcessesandAircraftMaintenanceChemicals(ApplicationforcopiesshouldbeaddressedtotheAmericanSocietyforTestingandMaterials,100BarrHarborDrive,WestConshohocken,PA19428-2959.)SOCIETYOFAUTOMOTIVEENGINEERS,INC.(SAE)AMS2759/9HydrogenEmbrittlementRelief(Baking)OfSteelParts(ApplicationforcopiesshouldbeaddressedtotheSocietyOfAutomotiveEngineers,Inc.,400CommonwealthDrive,Warrendale,PA15096.)2.4Orderofprecedence.Intheeventofaconflictbetweenthetextofthisdocumentandthereferencescitedherein,thetextofthisdocumenttakesprecedence.Nothinginthisdocument,however,supersedesapplicablelawsandregulationsunlessaspecificexemptionhasbeenobtained.MIL-DTL-13924D33.REQUIREMENTS3.1Materials.Thematerialsfortheblackeningprocessesshallbeselectedbythecontractor.Theselectedmaterialsshallresultinblackcoatingsmeetingalltheapplicablerequirementsofthisspecification.3.2Preparationofbasismetal.Priortotheapplicationoftheblackcoatings,thebasismetalshallbethoroughlycleaned.Thecleanedsurfacesshallbefreeofrust,scale,grease,oil,paint,orotherforeignmatter,andshallpassthewaterbreaktestdescribedinMIL-C-53072.Cleaningmaterialsandmethodsshallbeattheoptionofthecontractor.Thecleaningprocessshallbeperformedwithoutmeasurableabrasionorerosion.3.2.1Stressrelief.Unlessotherwisespecifiedforaparticularenditemspecificationordrawing,afterformingandhardening,andpriortocleaningandcoating,objectionableresidualstressinferrousalloypartshavingahardnessgreaterthan40HRCshallberelievedbysuitableheattreatment.Thetemperatureshallbesuchthatmaximumreliefisgivenwithouthardnessbeingreducedtolessthanthespecifiedminimum.Stressreliefisnotnecessarywhereithasbeendemonstratedthatcoatinghasnoharmfuleffectonthecoatedpart.3.2.2Coatingasafinalprocess.Unlessotherwisespecified,theblackcoatingsshallbeappliedafterallmachining,forming,welding,coldstraighteningandheattreatmenthavebeencompleted