Designation:A890/A890M−13StandardSpecificationforCastings,Iron-Chromium-Nickel-MolybdenumCorrosion-Resistant,Duplex(Austenitic/Ferritic)forGeneralApplication1ThisstandardisissuedunderthefixeddesignationA890/A890M;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(´)indicatesaneditorialchangesincethelastrevisionorreapproval.1.Scope*1.1Thisspecificationcoversagroupofcastduplexstainlesssteels(austenitic/ferritic).1.2Theduplexstainlesssteelalloysofferacombinationofenhancedmechanicalpropertiesandcorrosionresistancewhenproperlybalancedincompositionandproperlyheattreated.Ferritelevelsarenotspecified,butthesealloyswilldeveloparangeofapproximately30to60%ferritewiththebalanceaustenite.Itistheresponsibilityofthepurchasertodeterminewhichgradeshallbefurnisheddependingondesignandserviceconditions,mechanicalproperties,andcorrosion-resistantcharacteristics.NOTE1—Becauseofthepossibilityofprecipitationofembrittlingphases,thegradesincludedinthisspecificationarenotrecommendedforserviceattemperaturesabove600ºF[315ºC].1.3ThevaluesstatedineitherSIunitsorinch-poundunitsaretoberegardedseparatelyasstandard.Thevaluesstatedineachsystemmaynotbeexactequivalents;therefore,eachsystemshallbeusedindependentlyoftheother.Combiningvaluesfromthetwosystemsmayresultinnon-conformancewiththestandard.1.3.1Withinthetext,theSIunitsareshowninbrackets.2.ReferencedDocuments2.1ASTMStandards:2A370TestMethodsandDefinitionsforMechanicalTestingofSteelProductsA732/A732MSpecificationforCastings,Investment,Car-bonandLowAlloySteelforGeneralApplication,andCobaltAlloyforHighStrengthatElevatedTemperaturesA781/A781MSpecificationforCastings,SteelandAlloy,CommonRequirements,forGeneralIndustrialUseE29PracticeforUsingSignificantDigitsinTestDatatoDetermineConformancewithSpecificationsE562TestMethodforDeterminingVolumeFractionbySystematicManualPointCountE1245PracticeforDeterminingth...
