Designation:E1268−01(Reapproved2016)StandardPracticeforAssessingtheDegreeofBandingorOrientationofMicrostructures1ThisstandardisissuedunderthefixeddesignationE1268;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(´)indicatesaneditorialchangesincethelastrevisionorreapproval.INTRODUCTIONSegregationoccursduringthedendriticsolidificationofmetalsandalloysandisalignedbysubsequentdeformation.Solid-statetransformationsmaybeinfluencedbytheresultingmicrosegre-gationpatternleadingtodevelopmentofalayeredorbandedmicrostructure.Themostcommonexampleofbandingisthelayeredferrite-pearlitestructureofwroughtlow-carbonandlow-carbonalloysteels.Otherexamplesofbandingincludecarbidebandinginhypereutectoidtoolsteelsandmartensitebandinginheat-treatedalloysteels.Thispracticecoversprocedurestodescribetheappearanceofbandedstructures,proceduresforcharacterizingtheextentofbanding,andamicroindentationhardnessprocedurefordeterminingthedifferenceinhardnessbetweenbandsinheattreatedspecimens.Thestereologicalmethodsmayalsobeusedtocharacterizenon-bandedmicrostructureswithsecondphaseconstituentsoriented(elongated)invaryingdegreesinthedeformationdirection.1.Scope1.1Thispracticedescribesaproceduretoqualitativelydescribethenatureofbandedororientedmicrostructuresbasedonthemorphologicalappearanceofthemicrostructure.1.2Thispracticedescribesstereologicalproceduresforquantitativemeasurementofthedegreeofmicrostructuralbandingororientation.NOTE1—Althoughstereologicalmeasurementmethodsareusedtoassessthedegreeofbandingoralignment,themeasurementsareonlymadeonplanesparalleltothedeformationdirection(thatis,alongitudinalplane)andthethree-dimensionalcharacteristicsofthebandingoralign-mentarenotevaluated.1.3Thispracticedescribesamicroindentationhardnesstestprocedureforassessingthemagnitudeofthehardnessdiffer-encespresentinbandedheat-treatedsteels.Forfullymarten-siticcarbonan...
