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【英文标准名称】:StandardPracticeforVerificationofConstantAmplitudeDynamicForcesinanAxialFatigueTestingSystem
【原文标准名称】:轴向疲劳试验系统中恒振幅动态力验证的标准实施规范
【标准号】:ASTME467-2008
【标准状态】:现行
【国别】:美国
【发布日期】:2008
【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】:E08.03
【标准类型】:(Practice)
【标准水平】:()
【中文主题词】:
【英文主题词】:Axialloadingtests;Constant-load-amplitudefatiguecrackgrowthrates;Displacement;Dynamicverificationdata;Dynamometertesting;Fatigue;Statictests--metals/alloys;Verification
【摘要】:Itiswellunderstoodhowtomeasuretheforcesappliedtoaspecimenunderstaticconditions.PracticesE4detailstherequiredprocessforverifyingthestaticforcemeasurementcapabilitiesoftestingmachines.Duringdynamicoperationhowever,additionalerrorsmaymanifestthemselvesinatestingmachine.Furtherverificationisnecessarytoconfirmthedynamicforcemeasurementcapabilitiesoftestingmachines.Note18212;ThestaticmachineverificationaccomplishedbyPracticesE4simplyestablishesthereference.Indicatedforcesmeasuredfromtheforcecellarecomparedwiththedynamometerconditionedforcesstaticallyforconfirmationandthendynamicallyfordynamicverificationofthefatiguetestingsystem''sforceoutput.Note28212;Thedynamicaccuracyoftheforcecell''soutputwillnotalwaysmeettheaccuracyrequirementofthisstandardwithoutcorrection.Dynamiccorrectiontotheforcecelloutputcanbeappliedprovidedthatverificationisperformedafterthecorrectionhasbeenapplied.Note38212;Overalltestaccuracyisacombinationofmeasurementaccuracyandcontrolaccuracy.Thispracticeprovidesmethodstoevaluateeitherorboth.Ascontrolaccuracyisdependentonmanymorevariablesthanmeasurementaccuracyitisimperativethatthetestoperatorutilizeappropriatemeasurementtoolstoconfirmthatthetestingmachinex2019;scontrolbehaviorisconsistentbetweenverificationactivitiesandactualtestingactivities.Dynamicerrorsareprimarilyspandependent,notleveldependent.Thatis,theerrorforaparticularforceendlevelduringdynamicoperationisdependentontheimmediatelyprecedingforceendlevel.Largerspansimplylargerabsoluteerrorsforthesameforceendlevel.Duetothemanytestmachinefactorsthatinfluencedynamicforceaccuracy,verificationisrecommendedforeverynewcombinationofpotentialerrorproducingfactors.Primaryfactorsarespecimendesign,machineconfiguration,testfrequency,andloadingspan.Clearly,performingafullverificationforeachconfigurationisoftenimpractical.Toaddressthisproblem,dynamicverificationistakenintwoparts.First,oneormorefullverificationsareperformedatleastannually.Themainbodyofthispracticedescribesthatprocedure.Thisprovidesthemostaccurateestimateofdynamicerrors,asitwillaccountforelectronicaswellasacceleration-inducedsourcesoferror.Thesecondpart,describedinAnnexA1,isasimplifiedverificationprocedure.Itprovidesasimplifiedmethodofestimatingacceleration-inducederrorsonly.Thisprocedureistobeusedforcommonconfigurationchanges(thatis,specimen/grip/crossheadheightchanges).Dynamicverificationofthefatiguesystemisrecommendedovertheentirerangeofforceandfrequencyoverwhichtheplannedfatiguetestseriesistobeperformed.Endlevelsarelimitedtothemachine''sverifiedstaticforceasdefinedbythecurrentstaticforceverificationwhentestedinaccordancewithPracticesE4.Note48212;Thereisuncertaintyastowhetherornotthevibrationinaframewillbedifferentwhenoperatingincompressionasopposedtotension.Asaconsequence,thispracticerecommendsperformingverificationsatmaximumtensionandmaximumcompressionendlevels.Thetotalspandoesnotneedtobebetweenthosetwolevels,butcanbeperformedastwotests.Note58212;Primaryelectroniccharacteristicsaffectingdynamicmeasurementaccuracyarenoiseandbandwidth.............
【中国标准分类号】:H22
【国际标准分类号】:77_040_10
【页数】:11P.;A4
【正文语种】:英语