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1、Designation:D5045?14StardTestMethodsfPlaneStrainFractureToughnessStrainEnergyReleaseRateofPlasticMaterials1ThisstardisissuedunderthefixeddesignationD5045thenumberimmediatelyfollowingthedesignationindicatestheyearofiginal

2、adoptioninthecaseofrevisiontheyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperepsilon()indicatesaneditialchangesincethelastrevisionreapproval.1.Scope1.1Thesetestmethodsaredesignedtoacterizet

3、hetoughnessofplasticsintermsofthecriticalstressintensityfactKIctheenergyperunitareaofcracksurfacecriticalstrainenergyreleaserateGIcatfractureinitiation.1.2Twotestinggeometriesarecoveredbythesetestmethodssingleedgenotchbe

4、nding(SENB)compacttension(CT).1.3Theschemeusedassumeslinearelasticbehaviofthecrackedspecimensocertainrestrictionsonlinearityoftheloaddisplacementdiagramareimposed.1.4Astateofplanestrainatthecracktipisrequired.Specimenthi

5、cknessmustbesufficienttoensurethisstressstate.1.5Thecrackmustbesufficientlysharptoensurethataminimumvalueoftoughnessisobtained.1.6ThesignificanceofthesetestmethodsmanyconditionsoftestingareidenticaltothoseofTestMethodE39

6、9therefeinmostcasesappearherewithmanysimilaritiestothemetalsstard.HowevercertainconditionsspecificationsnotcoveredinTestMethodE399butimptantfplasticsareincluded.1.7ThisprotocolcoversthedeterminationofGIcaswellwhichisofpa

7、rticularimptancefplastics.1.8ThesetestmethodsgivegeneralinfmationconcerningtherequirementsfKIcGIctesting.AswithTestMethodE399twoannexesareprovidedwhichgivethespecificrequirementsftestingoftheSENBCTgeometries.1.9Testdatao

8、btainedbythesetestmethodsarerelevantappropriatefuseinengineeringdesign.1.10Thisstarddoesnotpurpttoaddressallofthesafetyconcernsifanyassociatedwithitsuse.Itistheresponsibilityoftheuserofthisstardtoestablishappropriatesafe

9、tyhealthpracticesdeterminetheapplicabilityofregulatylimitationspritouse.NOTE1—ThisstardISO13586addressthesamesubjectmatterbutdifferintechnicalcontent.2.ReferencedDocuments2.1ASTMStards:2D638TestMethodfTensilePropertiesof

10、PlasticsD4000ClassificationSystemfSpecifyingPlasticMaterialsE399TestMethodfLinearElasticPlaneStrainFractureToughnessKIcofMetallicMaterialsE691PracticefConductinganInterlabatyStudytoDeterminethePrecisionofaTestMethod3.Ter

11、minology3.1Definitions:3.1.1compacttensionn—specimengeometryconsistingofsingleedgenotchedplateloadedintension.See3.1.5freferencetoadditionaldefinition.3.1.2criticalstrainenergyreleaserateGIcn—toughnessparameterbasedonene

12、rgyrequiredtofracture.See3.1.5freferencetoadditionaldefinition.3.1.3planestrainfracturetoughnessKIcn—toughnessparameterindicativeoftheresistanceofamaterialtofracture.See3.1.5freferencetoadditionaldefinition.3.1.4singleed

13、genotchedbendn—specimengeometryconsistingofcenternotchedbeamloadedinthreepointbending.See3.1.5freferencetoadditionaldefinition.3.1.5ReferenceismadetoTestMethodE399fadditionalexplanationofdefinitions.3.2DefinitionsofTerms

14、SpecifictoThisStard:3.2.1yieldstressn—stressatfractureisused.Theslopeofthestressstraincurveisnotrequiredtobezero.See7.2freferencetoadditionaldefinition.1ThesetestmethodsareunderthejurisdictionofASTMCommitteeD20onPlastics

15、isthedirectresponsibilityofSubcommitteeD20.10onMechanicalProperties.CurrenteditionapprovedDec.12014.PublishedDecember2014.iginallyapprovedin1990.Lastpreviouseditionapprovedin1999asD504599(2007)?1.DOI:10.1520D504514.2Fref

16、erencedASTMstardsvisittheASTMwebsitewww.astm.gcontactASTMCustomerServiceat.FAnnualBookofASTMStardsvolumeinfmationrefertothestard’sDocumentSummarypageontheASTMwebsite.ASummaryofChangessectionappearsattheendofthisstardCopy

17、right?ASTMInternational100BarrHarbDrivePOBoxC700WestConshohockenPA194282959.UnitedStates17.SpecimenSizeConfigurationsPreparation7.1SpecimenSize:7.1.1SENBCTgeometriesarerecommendedoverotherconfigurationsbecausethesehavepr

18、edominantlybendingstressstateswhichallowsmallerspecimensizestoachieveplanestrain.SpecimendimensionsareshowninFig.3(ab).IfthematerialissuppliedinthefmofasheetthespecimenthicknessBisidenticalwiththesheetthicknessindertomax

19、imizethisdimension.ThespecimenwidthWisW=2B.Inbothgeometriesthecracklengthashallbeedsuchthat0.45aW0.55.7.1.2Inderfaresulttobeconsideredvalidaccdingtothesetestmethodsthefollowingsizecriteriamustbesatisfied:Ba~W2a!.2.5~KQσy

20、!2(1)where:KQ=theconditionaltrialKIcvalue(seeSection9)σy=theyieldstressofthematerialfthetemperatureloadingrateofthetest.ThecriteriarequirethatBmustbesufficienttoensureplanestrainthat(W?a)besufficienttoavoidexcessiveplast

21、icityintheligament.If(W?a)istoosmallnonlinearityinloadingoccursthenincreasingtheWBratiotoamaximumof4ispermittedfSENBspecimens.7.2YieldStress:7.2.1Theyieldstressσyistobetakenfromthemaximumloadinauniaxialtensiletest.Theyie

22、ldstresstestcanbeperfmedinaconstantstrokerateuniaxialtensiletestwheretheloadingtimetoyieldiswithin620%oftheactualloadingtimeobservedinthefracturetest.ThedefinitionofyieldstressisnotidenticaltothatfoundinTestMethodD638whi

23、chrequiresazeroslopetothestressstraincurve.Ifitisestablishedthat2.5(KQσy)2issubstantiallylessthanthespecimenthicknessemployedthenacrespondinglysmallerspecimencanbeused.7.2.2Yieldingintensiletestsinmostpolymerscanbeachiev

24、edbycarefullypolishingthespecimensides.Ifyieldingdoesnotoccurbrittlefractureisobservedthestressatfractureshallbeusedinthecriteriatogiveaconservativesizevalue.7.2.3Ifatensiletestcannotbeperfmedthenanalternativemethodistou

25、se0.7timesthecompressiveyieldstress.7.2.4Ifthefmoftheavailablematerialissuchthatitisnotpossibletoobtainaspecimenwithbothcracklengththicknessgreaterthan2.5(KIcσy)2itisnotpossibletomakeavalidKIc(GIc)measurementaccdingtothe

26、setestmethods.7.2.5Thetestmethodemployedfdeterminingyieldstressasmentionedin7.2.1–7.2.4mustberepted.7.3SpecimenConfigurations:7.3.1StardSpecimens—TheconfigurationsofthetwogeometriesareshowninFig.3(a)(SENB)Fig.3(b)(CT)whi

27、charetakenfromAnnexesA3A4respectivelyofTestMethodE399.Thecracklengtha(crackprenotchplusraznotch)isnominallyequaltothethicknessBisbetween0.450.55timesthewidthW.TheratioWBisnominallyequaltotwo.7.3.2AlternativeSpecimens—Inc

28、ertaincasesitmaybedesirabletousespecimenshavingWBratiosotherthantwo.Alternativeproptionsfbendspecimensare2WB4.ThisalternativeshallhavethesameaWSWratiosasthestardspecimens(S=supptspan).7.3.3DisplacementCrectionSpecimens—S

29、eparatelypreparedunnotchedspecimenconfigurationsfthedeterminationofthedisplacementcrectionmentionedin9.2areshowninFig.4(a)fSENBinFig.4(b)fCTconfigurationsrespectively.7.4SpecimenPreparation:FIG.2TensionTestingClevisDesig

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