Standard Test Methods for Determining Average Grai

Designation:E112–96(Reapproved2004)e2StandardTestMethodsforDeterminingAverageGrainSize1ThisstandardisissuedunderthefixeddesignationE112;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(e)indicatesaneditorialchangesincethelastrevisionorreapproval.ThisstandardhasbeenapprovedforusebyagenciesoftheDepartmentofDefense.e1NOTE—Reference(2)waseditoriallycorrectedinMay2006.e2NOTE—EquationA1.9waseditoriallycorrectedinNovember2006.INTRODUCTIONThesetestmethodsofdeterminationofaveragegrainsizeinmetallicmaterialsareprimarilymeasuringproceduresand,becauseoftheirpurelygeometricbasis,areindependentofthemetaloralloyconcerned.Infact,thebasicproceduresmayalsobeusedfortheestimationofaveragegrain,crystal,orcellsizeinnonmetallicmaterials.Thecomparisonmethodmaybeusedifthestructureofthematerialapproachestheappearanceofoneofthestandardcomparisoncharts.Theinterceptandplanimetricmethodsarealwaysapplicablefordeterminingaveragegrainsize.However,thecomparisonchartscannotbeusedformeasurementofindividualgrains.1.Scope1.1Thesetestmethodscoverthemeasurementofaveragegrainsizeandincludethecomparisonprocedure,theplanimet-ric(orJeffries)procedure,andtheinterceptprocedures.Thesetestmethodsmayalsobeappliedtononmetallicmaterialswithstructureshavingappearancessimilartothoseofthemetallicstructuresshowninthecomparisoncharts.Thesetestmethodsapplychieflytosinglephasegrainstructuresbuttheycanbeappliedtodeterminetheaveragesizeofaparticulartypeofgrainstructureinamultiphaseormulticonstituentspecimen.1.2Thesetestmethodsareusedtodeterminetheaveragegrainsizeofspecimenswithaunimodaldistributionofgrainareas,diameters,orinterceptlengths.Thesedistributionsareapproximatelylognormal.Thesetestmethodsdonotcovermethodstocharacterizethenatureofthesedistributions.CharacterizationofgrainsizeinspecimenswithduplexgrainsizedistributionsisdescribedinTestMethodsE1181.Mea-surementofindividual,verycoarsegrainsinafinegrainedmatrixisdescribedinTestMethodsE930.1.3Thesetestmethodsdealonlywithdeterminationofplanargrainsize,thatis,characterizationofthetwo-dimensionalgrainsectionsrevealedbythesectioningplane.Determinationofspatialgrainsize,thatis,measurementofthesizeofthethree-dimensionalgrainsinthespecimenvolume,isbeyondthescopeofthesetestmethods.1.4Thesetestmethodsdescribetechniquesperformedmanuallyusingeitherastandardseriesofgradedchartimagesforthecomparisonmethodorsimpletemplatesforthemanualcountingmethods.Utilizationofsemi-automaticdigitizingtabletsorautomaticimageanalyzerstomeasuregrainsizeisdescribedinTestMethodsE1382.1.5Thesetestmethodsdealonlywiththerecommendedtestmethodsandnothinginthemshouldbeconstruedasdefiningorestablishinglimitsofacceptabilityorfitnessofpurposeofthematerialstested.1.6ThemeasuredvaluesarestatedinSIunits,whichareregardedasstandard.Equivalentinch-poundvalues,whenlisted,areinparenthesesandmaybeapproximate.1.7Thisstandarddoesnotpurporttoaddressallofthesafetyconcerns,ifany,associatedwithitsuse.Itistheresponsibilityoftheuserofthisstandardtoestablishappro-priatesafetyandhealthpracticesanddeterminetheapplica-bilityofregulatorylimitationspriortouse.1.8Theparagraphsappearinthefollowingorder:SectionNumberScope1ReferencedDocuments2Terminology3SignificanceandUse4GeneralitiesofApplication5Sampling6TestSpecimens7Calibration8PreparationofPhotomicrographs9ComparisonProcedure101ThesetestmethodsareunderthejurisdictionofASTMCommitteeE04onMetallographyandarethedirectresponsibilityofSubcommitteeE04.08onGrainSize.CurrenteditionapprovedNov.4,2004.PublishedNovember2004.Originallyapprovedin1955.Lastpreviouseditionapproved1996asE112–96e3.1Copyright©ASTMInternational,100BarrHarborDrive,POBoxC700,WestConshohocken,PA19428-2959,UnitedStates.Planimetric(Jeffries)Procedure11GeneralInterceptProcedures12HeynLinearInterceptProcedure13CircularInterceptProcedures14HilliardSingle-CircleProcedure14.2AbramsThree-CircleProcedure14.3StatisticalAnalysis15SpecimenswithNon-equiaxedGrainShapes16SpecimensContainingTwoorMorePhasesorConstituents17Report18PrecisionandBias19Keywords20Annexes:BasisofASTMGrainSizeNumbersAnnexA1EquationsforConversionsAmongVariousGrainSizeMeasurementsAnnexA2AusteniteGrainSize,FerriticandAusteniticSteelsAnnexA3FractureGrainSizeMethodAnnexA4RequirementsforWroughtCopperandCopper-BaseAlloysAnnexA5ApplicationtoSpecialSituationsAnnexA6Appendixes:ResultsofInterlaboratoryGrainSizeDeterminationsAppen-dixX1ReferencedAdjunctsAppen-dixX22.ReferencedDocuments2.1ASTMStandards:2E3PracticeforPreparationofMetallographicSpecimensE7TerminologyRelatingtoMetallographyE407PracticeforMicroetchingMetalsandAlloysE562PracticeforDeterminingVolumeFractionbySys-tematicManualPointCountE691PracticeforConductinganInterlaboratoryStudytoDeterminethePrecisionofaTestMethodE883GuideforReflected-LightPhotomicrographyE930TestMethodsforEstimatingtheLargestGrainOb-servedinaMetallographicSection(ALAGrainSize)E1181TestMethodsforCharacterizingDuplexGrainSizesE1382TestMethodsforDetermin