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1、Designation:E45?18aStardTestMethodsfDeterminingtheInclusionContentofSteel1ThisstardisissuedunderthefixeddesignationE45thenumberimmediatelyfollowingthedesignationindicatestheyearofiginaladoptioninthecaseofrevisiontheyearo

2、flastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperepsilon()indicatesaneditialchangesincethelastrevisionreapproval.ThisstardhasbeenapprovedfusebyagenciesoftheU.S.DepartmentofDefense.1.Scope1.1Theset

3、estmethodscoveranumberofrecognizedproceduresfdeterminingthenonmetallicinclusioncontentofwroughtsteel.Macroscopicmethodsincludemacroetchfracturestepdownmagicparticletests.Microscopicmethodsincludefivegenerallyacceptedsyst

4、emsofexamination.Inthesemicroscopicmethodsinclusionsareassignedtoacategybasedonsimilaritiesinmphologynotnecessarilyontheirchemicalidentity.Metallographictechniquesthatallowsimpledifferentiationbetweenmphologicallysimilar

5、inclusionsarebrieflydiscussed.Whilethemethodsareprimarilyintendedfratinginclusionsconstituentssuchascarbidesnitridescarbonitridesbidesintermetallicphasesmayberatedusingsomeofthemicroscopicmethods.Insomecasesalloysotherth

6、ansteelsmayberatedusingonemeofthesemethodsthemethodswillbedescribedintermsoftheiruseonsteels.1.2ThesetestmethodscoverprocedurestoperfmJKtypeinclusionratingsusingautomaticimageanalysisinaccdancewithmicroscopicmethodsAD.1.

7、3Dependingonthetypeofsteelthepropertiesrequiredeitheramacroscopicamicroscopicmethodfdeterminingtheinclusioncontentcombinationsofthetwomethodsmaybefoundmostsatisfacty.1.4Thesetestmethodsdealonlywithrecommendedtestmethodsn

8、othinginthemshouldbeconstruedasdefiningestablishinglimitsofacceptabilityfanygradeofsteel.1.5ThevaluesstatedinSIunitsaretoberegardedasthestard.Valuesinparenthesesareconversionsareapproximate.1.6Thisstarddoesnotpurpttoaddr

9、essallofthesafetyconcernsifanyassociatedwithitsuse.Itistheresponsibilityoftheuserofthisstardtoestablishappropriatesafetyhealthenvironmentalpracticesdeterminetheapplicabilityofregulatylimitationspritouse.1.7Thisinternatio

10、nalstardwasdevelopedinaccdancewithinternationallyrecognizedprinciplesonstardizationestablishedintheDecisiononPrinciplesftheDevelopmentofInternationalStardsGuidesRecommendationsissuedbytheWldTradeganizationTechnicalBarrie

11、rstoTrade(TBT)Committee.2.ReferencedDocuments2.1ASTMStards:2E3GuidefPreparationofMetallographicSpecimensE7TerminologyRelatingtoMetallographyE381MethodofMacroetchTestingSteelBarsBilletsBloomsFgingsE709GuidefMagicParticleT

12、estingE768GuidefPreparingEvaluatingSpecimensfAutomaticInclusionAssessmentofSteelE1245PracticefDeterminingtheInclusionSecondPhaseConstituentContentofMetalsbyAutomaticImageAnalysisE1444PracticefMagicParticleTestingE1951Gui

13、defCalibratingReticlesLightMicroscopeMagnifications2.2SAEStards:3J422RecommendedPracticefDeterminationofInclusionsinSteel2.3AerospaceMaterialSpecifications:3AMS2300PremiumAircraftQualitySteelCleanliness:MagicParticleInsp

14、ectionProcedureAMS2301AircraftQualitySteelCleanliness:MagicParticleInspectionProcedureAMS2303AircraftQualitySteelCleanliness:MartensiticCrosionResistantSteelsMagicParticleInspectionProcedureAMS2304SpecialAircraftQualityS

15、teelCleanliness:MagicParticleInspectionProcedure1ThesetestmethodsareunderthejurisdictionofASTMCommitteeE04onMetallographyisthedirectresponsibilityofSubcommitteeE04.09onInclusions.CurrenteditionapprovedJune12018.Published

16、September2018.iginallyapprovedin1942.Lastpreviouseditionapprovedin2018asE45–18.DOI:10.1520E004518A.2FreferencedASTMstardsvisittheASTMwebsitewww.astm.gcontactASTMCustomerServiceat.FAnnualBookofASTMStardsvolumeinfmationref

17、ertothestard’sDocumentSummarypageontheASTMwebsite.3AvailablefromSAEInternational(SAE)400CommonwealthDr.WarrendalePA150960001:www.sae.g.Copyright?ASTMInternational100BarrHarbDrivePOBoxC700WestConshohockenPA194282959.Unite

18、dStatesThisinternationalstardwasdevelopedinaccdancewithinternationallyrecognizedprinciplesonstardizationestablishedintheDecisiononPrinciplesftheDevelopmentofInternationalStardsGuidesRecommendationsissuedbytheWldTradegani

19、zationTechnicalBarrierstoTrade(TBT)Committee.1severitylevelboth.Alsobyagreementqualitativepracticesmaybeusedwhereonlythehighestseverityratingsfeachinclusiontypethicknessaredefinedthenumberoffieldscontainingthesehighestse

20、verityratingsaretabulated.4.7Thesetestmethodsareintendedfuseonwroughtmetallicstructures.Whileaminimumlevelofdefmationisnotspecifiedthetestmethodsarenotsuitablefuseoncaststructuresonlightlywkedstructures.4.8Guidelinesarep

21、rovidedtorateinclusionsinsteelstreatedwithrareearthadditionscalciumbearingcompounds.Whensuchsteelsareevaluatedthetestreptshoulddescribethenatureoftheinclusionsratedaccdingtoeachinclusioncategy(ABCD).4.9InadditiontotheTes

22、tMethodsE45JKratingsbasic(suchasusedinPracticeE1245)stereologicalmeasurements(fexamplethevolumefractionofsulfidesoxidesthenumberofsulfidesoxidespersquaremillimeterthespacingbetweeninclusionssofth)maybeseparatelydetermine

23、daddedtothetestreptifdesiredfadditionalinfmation.Thispracticehoweverdoesnotaddressthemeasurementofsuchparameters.MACROSCOPICMETHODS5.MacroscopicalTestMethodsOverview5.1Summary:5.1.1MacroetchTest—Themacroetchtestisusedtoi

24、ndicateinclusioncontentdistributionusuallyinthecrosssectiontransversetothedirectionofrollingfging.Insomeinstanceslongitudinalsectionsarealsoexamined.Testsarepreparedbycuttingmachiningasectionthroughthedesiredareaetchingw

25、ithasuitablereagent.Asolutionofoneparthydrochlicacidonepartwateratatemperatureof71to82C(160to180F)iswidelyused.Asthenameofthistestimpliestheetchedsurfaceisexaminedvisuallyatlowmagnificationfinclusions.Detailsofthistestar

26、eincludedinMethodE381.Thenatureofquestionableindicationsshouldbeverifiedbymicroscopicexaminationothermeansofinspection.5.1.1.1Sulfidesarerevealedaspitswhenthestardetchantdescribedin5.1.1isused.5.1.1.2Onlylargeoxidesarere

27、vealedbythistestmethod.5.1.2FractureTest—Thefracturetestisusedtodeterminethepresencelocationofinclusionsasshownonthefractureofhardenedslicesapproximately9to13mm(3?8to1?2in.)thick.Thistestisusedmostlyfsteelswhereitispossi

28、bletoobtainahardnessofapproximately60HRCafracturegrainsizeof7finer.Testspecimensshouldnothaveexcessiveexternalindentationsnotchesthatguidethefracture.Itisdesirablethatfracturebeinthelongitudinaldirectionapproximatelyacro

29、ssthecenteroftheslice.Thefracturedsurfacesareexaminedvisuallyatmagnificationsuptoapproximatelytendiametersthelengthdistributionofinclusionsisnoted.Heattintingblueingwillincreasevisibilityofoxidestringers.ISO3763providesa

30、tmethodffracturesurfaceinclusionratings.Insomeinstancesindicationsassmallas0.40mm(1?64in.)inlengtharerecded.5.1.3StepDownMethod—Thestepdowntestmethodisusedtodeterminethepresenceofinclusionsonmachinedsurfacesofrolledfgeds

31、teel.Thetestsampleismachinedtospecifieddiametersbelowthesurfacesurveyedfinclusionsundergoodilluminationwiththeunaidedeyewithlowmagnification.Insomeinstancestestsamplesaremachinedtosmallerdiametersffurtherexaminationafter

32、theiginaldiametersareinspected.Thistestisessentiallyusedtodeterminethepresenceofinclusions3mm(1?8in.)inlengthlonger.5.1.4MagicParticleMethod—Themagicparticlemethodisavariationofthestepdownmethodfferromagicmaterialsinwhic

33、hthetestsampleismachinedmagizedmagicpowderisapplied.Discontinuitiesassmallas0.40mm(1?64in.)inlengthcreatemagicleakagefieldsthatattractthemagicpowdertherebyoutliningtheinclusion.SeePracticeE1444GuideE709onmagicparticleexa

34、minationsfmedetailsoftheprocedure.RefertoAerospaceMaterialsSpecificationsAMS2300AMS2301AMS2303AMS2304.5.2Advantages:5.2.1Thesetestmethodsfacilitatetheexaminationofspecimenswithlargesurfaceareas.Thelargerinclusionsinsteel

35、whicharethemainconcerninmostcasesarenotunifmlydistributedthespacesbetweenthemarerelativelylargesothatthechancesofrevealingthemarebetterwhenlargerspecimensareexamined.5.2.2Specimensfmacroscopicexaminationmaybequicklyprepa

36、redbymachininggrinding.Ahighlypolishedsurfaceisnotnecessary.Themacroscopicmethodsaresufficientlysensitivetorevealthelargerinclusions.5.3Disadvantages:5.3.1Thesetestmethodsdonotdistinguishamongthedifferentinclusionshapes.

37、5.3.2Theyarenotsuitablefthedetectionofsmallglobularinclusionsofchainsofveryfineelongatedinclusions.5.3.3Themagicparticlemethodcanleadtoincrectinterpretationofmicrostructuralfeaturessuchasstreaksofretainedaustenitemicrose

38、gregationcarbidesincertainalloysthisisparticularlylikelyifhighmagizationcurrentsareemployed.MICROSCOPICMETHODS6.MicroscopicTestMethodsOverview6.1Microscopicmethodsareusedtoacterizethesizedistributionnumbertypeofinclusion

39、sonapolishedspecimensurface.Thismaybedonebyexaminingthespecimenwithalightmicroscopereptingthetypesofinclusionsencounteredaccompaniedbyafewrepresentativephotomicrographs.Thismethodhoweverdoesnotlenditselftoaunifmreptingst

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