ANSI/ASTM D6395-1999 硬塑料耐平地软冲击试验方法

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【英文标准名称】:TestMethodforFlatwiseFlexuralImpactResistanceofRigidPlastics
【原文标准名称】:硬塑料耐平地软冲击试验方法
【标准号】:ANSI/ASTMD6395-1999
【标准状态】:现行
【国别】:美国
【发布日期】:1999
【实施或试行日期】:1999-04-28
【发布单位】:美国国家标准学会(US-ANSI)
【起草单位】:
【标准类型】:()
【标准水平】:()
【中文主题词】:塑料;测试方法;试验方法
【英文主题词】:testmethods;plastics
【摘要】:TheresistanceofplasticstobreakagebyflexuralshockmaybedeterminedbytestmethodssuchasthosecontainedinTestMethodD256.Specimensusedinthosetestmethodsfeatureamillednotchtopromotebrittlefracture.Thetestspecimensarestruckbyapendulumwiththedepthdimensionparalleltothedirectionofpendulumswing.Thistestmethodisdifferentiatedfromtheothersbyitsapplicationtotheassessmentoftheaffectonimpactresistanceofchangesinthesurfaceofspecimensresultingfromweatheringorotherexposure.Inthistestmethod,specimensarestruckbyapendulumwiththedepthdimensionperpendiculartothedirectionofpendulumswing.TestMethodD5420mayalsobeusedtoconducttestingofweatheredorexposedspecimens.ThistestmethodisdifferentiatedfromGardnerImpactbythesmallersizeofthespecimens,whichmayresultinsubstantiallyhigherproductivityofacceleratedweatheringinstruments.Additionally,thistestmethodprovidesmultipledatafromasinglespecimenforcharacterizationofwithinspecimenvariability.Thistestmethoddescribesthedeterminationoftheresistanceofrigidplasticstripspecimenstobreakageorpermanentdeformationwhenoneendofthespecimenissubjectedtoanimpactuponitswidefacewhiletheotherendofthespecimenisfirmlyclamped.Thistestmethodisapplicabletospecimensof1.60mm[0.0625in.]thickness.However,thelimitsofapplicabilityofthetestarenotsharplydefined,andspecimenshavingotherdimensionsmayfrequentlybeused.Forspecimensofthicknessesotherthan1.60mm[0.0625in.]theratioofthedistancebetweenthetopoftheclampandthecenterlineoftheroundedstrikingedgetothespecimenthicknessmustbe2.5?0.1.Thistestmethodmeasurestherelativeimpactresistanceofsampleshavingapproximatelythesamethickness.Normalizationoftheimpactresistancetounitcross-sectionalareaonlypartlycompensatesfortheeffectsofspecimenthicknessvariationbecause,atthefixedcantileverlength,theratioofshearstresstotensilestressinbendingincreaseswiththickness,andtheimportanceoftheseeffectsincontributingtotheenergyabsorbedisgreaterforductilethanforbrittlefailure.Thistestmethodisusedprimarilyasameansofassessing,foraseriesofsamples,changesrelativetoacontrolduetosometreatmentsuchasweatheringorexposuretoactiveenvironments.Ithasbeenparticularlyusefulasasensitiveindicatorofthedevelopmentofsurfacecracksorabrittlesurface.Theexistenceorformationofcracksinaninherentlybrittlesurfaceproducesmarkedloweringofimpactstrengthwhenthatsurfaceistheonesubjectedtotensioninthetest.Thistestmethodisnotgenerallyapplicabletomaterialssuchaselastomersornonrigidplasticsinwhichthereisnofracture,permanentdeformation,orotherchangeduetoyieldinginflexure.However,itmaybedesirabletotestsuchmaterialsasfilesamplestoestablishreferencepointswhenthetestisappliedasdescribedinThevaluesstatedinSIunitsaretoberegardedasthestandard.Thevaluesgiveninbracketsareforinformationonly.Thisstandarddoesnotpurporttoaddressallofthesafetyconcerns,ifany,associatedwithitsuse.Itistheresponsibilityoftheuserofthisstandardtoestablishappropriatesafetyandhealthpracticesanddeterminetheapplicabilityofregulatorylimitationspriortouse.Note1ThereisnoequivalentorsimilarISOstandard.
【中国标准分类号】:G31
【国际标准分类号】:83_080_01
【页数】:
【正文语种】:英语