Designation:A262−15StandardPracticesforDetectingSusceptibilitytoIntergranularAttackinAusteniticStainlessSteels1ThisstandardisissuedunderthefixeddesignationA262;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(´)indicatesaneditorialchangesincethelastrevisionorreapproval.ThisstandardhasbeenapprovedforusebyagenciesoftheU.S.DepartmentofDefense.1.Scope*1.1Thesepracticescoverthefollowingfivetests:1.1.1PracticeA—OxalicAcidEtchTestforClassificationofEtchStructuresofAusteniticStainlessSteels(Sections4to13,inclusive),1.1.2PracticeB—FerricSulfate-SulfuricAcidTestforDe-tectingSusceptibilitytoIntergranularAttackinAusteniticStainlessSteels(Sections14to25,inclusive),1.1.3PracticeC—NitricAcidTestforDetectingSuscepti-bilitytoIntergranularAttackinAusteniticStainlessSteels(Sections26to36,inclusive),1.1.4PracticeE—Copper–CopperSulfate–SulfuricAcidTestforDetectingSusceptibilitytoIntergranularAttackinAusteniticStainlessSteels(Sections37to46,inclusive),and1.1.5PracticeF—Copper–CopperSulfate–50%SulfuricAcidTestforDetectingSusceptibilitytoIntergranularAttackinMolybdenum-BearingAusteniticStainlessSteels(Sections47to58,inclusive).1.2TheOxalicAcidEtchTestisarapidmethodofidentifying,bysimpleetching,thosespecimensofcertainstainlesssteelgradesthatareessentiallyfreeofsusceptibilitytointergranularattackassociatedwithchromiumcarbideprecipitates.Thesespecimenswillhavelowcorrosionratesincertaincorrosiontestsandthereforecanbeeliminated(screened)fromtestingas“acceptable.”Theetchtestisapplicableonlytothosegradeslistedintheindividualhotacidtestsandclassifiesthespecimenseitheras“acceptable”oras“suspect.”1.3Theferricsulfate-sulfuricacidtest,thecopper–coppersulfate–50%sulfuricacidtest,andthenitricacidtestarebasedonweightlossdeterminationsand,thus,provideaquantitativemeasureoftherelativeperformanceofspecimensevaluated.Incontrast,thecopper–copp...
