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【英文标准名称】:StandardTestMethodforImpactTestingofMiniaturizedCharpyV-NotchSpecimens
【原文标准名称】:微型夏比V型冲击试样缺口的标准试验方法
【标准号】:ASTME2248-2009
【标准状态】:现行
【国别】:美国
【发布日期】:2009
【实施或试行日期】:
【发布单位】:美国材料与试验协会(US-ASTM)
【起草单位】:E28.07
【标准类型】:(TestMethod)
【标准水平】:()
【中文主题词】:
【英文主题词】:fractureappearance;impacttest;instrumentedimpacttest;lateralexpansion;miniaturizedCharpytest;notchedspecimens;pendulummachine
【摘要】:TherearecaseswhereitisimpracticalorimpossibletoprepareconventionalCVNspecimens.MCVNspecimensareanalternativeapproachforcharacterizingnotchedspecimenimpactbehavior.TypicalapplicationsincludeMCVNspecimenspreparedfromthebrokenhalvesofpreviouslytestedspecimens,fromthinproductformmaterial,orfrommaterialcutfromin-servicecomponents.ThisstandardestablishestherequirementsforperformingimpacttestsonMCVNspecimensfabricatedfrommetallicmaterials.Minimumrequirementsaregivenformeasurementandrecordingequipmentsuchthatsimilarsensitivityandcomparablemeasurements,ascomparedtoconventionalCVNtests,areachieved.TheusershouldbeawarethatthetransitionregiontemperaturedependencedataobtainedfromMCVNspecimensarenotdirectlycomparabletothoseobtainedfromfull-sizestandardCharpy-Vspecimensandsuitablecorrelationprocedureshavetobeemployedtoobtainductile-to-brittletransitiontemperature(DBTT)dataequivalenttothoseobtainedusingCVNspecimens.Inallinstances,correlationswillhavetobedevelopedtorelateuppershelfenergy(USE)datafromMCVNtesttoCVNcomparableenergylevels.ApplicationofMCVNtestdatatotheevaluationofferriticmaterialbehavioristheresponsibilityoftheuserofthistestmethod.MCVNtestdatashouldnotbeuseddirectlytodeterminethelowestallowableoperatingtemperatureforanin-servicematerial.Thedatamustbeinterpretedwithintheframeworkofafracturemechanicsassessment.WhilethisTestMethodtreatstheuseofaninstrumentedstrikerasanoption,theuseofinstrumentationintheimpacttestisrecommendedandisfullydescribedinTestMethodE2298.Inordertoestablishtheforce-displacementdiagram,itisnecessarytomeasuretheimpactforceasafunctionoftimeduringcontactofthestrikerwiththespecimen.Theareaundertheforce-displacementcurveisameasureofabsorbedenergy.Asanalternative,absorbedenergymaybeevaluateddirectlyfrommachinedialreading.Wheneverpossible,anopticalencodershallbeusedinplaceofthemachinedialbecauseanencoderhasbetterresolutionthanadial.1.1Thistestmethoddescribesnotched-barimpacttestingofmetallicmaterialsusingMiniaturizedCharpyV-Notch(MCVN)specimensandtestapparatus.Itprovides:(a)adescriptionoftheapparatus,(b)requirementsforinspectionandcalibration,(c)safetyprecautions,(d)sampling,(e)dimensionsandpreparationofspecimens,(f)testingprocedures,and(g)precisionandbias.1.2ThisstandardconcernsMiniaturizedCharpyV-Notchspecimens,forwhichalllineardimensions,includinglengthandnotchdepth,arereducedwithrespecttoatypeAstandardimpacttestspecimeninaccordancewithTestMethodsE23.Thesearenotthesameassub-sizespecimens,describedinAnnexA3ofTestMethodsE23,forwhichlength,notchangleandnotchdeptharethesameasforthestandardtypeACharpyspecimen.Seealso1.5below.1.3ComparisonoftheMCVNdatawithconventionalCharpyV-Notch(CVN)dataorapplicationoftheMCVNdata,orboth,totheevaluationofferriticmaterialbehavioristheresponsibilityoftheuserofthistestmethodandisnotexplicitlycoveredbythistestmethod.1.4ThevaluesstatedinSIunitsaretoberegardedasstandard.Nootherunitsofmeasurementareincludedinthisstandard.1.5Thisstandarddoesnotaddresstestingofsub-sizespecimensasdiscussedinTestMethodsE23.Thereadershouldunderstandthedistinctionbetweenminiatureandsubsiz......
【中国标准分类号】:H22
【国际标准分类号】:77_040_10
【页数】:6P.;A4
【正文语种】:英语