【英文标准名称】:StandardTestMethodsforImpactResistanceofPlasticFilmbytheFree-FallingDartMethod
【原文标准名称】:用钢锥自由下落法测试塑料薄膜抗冲击性的标准试验方法
【标准号】:ASTMD1709-2009
【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】:D20.19
【标准类型】:(TestMethod)
【标准水平】:()
【中文主题词】:
【英文主题词】:dropdart;impact;plasticfilm;Free-fallingdartmethod;Impactresistance--plastics;Plasticsheetandfilm;Polyethylene(PE)sheetandfilm
【摘要】:TestMethodsAandBareusedtoestablishtheweightofthedartwhen50%ofthespecimensfailundertheconditionsspecified.Dataobtainedbyonetestmethodcannotbecompareddirectlywiththeothertestmethodnorwiththoseobtainedfromtestsemployingdifferentconditionsofmissilevelocity,impingingsurfacediameter,effectivespecimendiameter,andthickness.Thevaluesobtainedbythesetestvariablesarehighlydependentonthemethodoffilmfabrication.TheresultsobtainedbyTestMethodsAandBaregreatlyinfluencedbythequalityoffilmundertest.Theconfidencelimitsofdataobtainedbythisprocedurecan,therefore,varysignificantly,dependingonthesamplequality,uniformityoffilmgage,diemarks,contaminants,etc.(seeSection15).TestMethodsAandBhavebeenfoundusefulforspecificationpurposes.Correlationbetweentestresultsandfieldperformancecanusuallybeestablished.Theimpactresistanceofplasticfilm,whilepartlydependentonthickness,hasnosimplecorrelationwithsamplethickness.Hence,impactvaluescannotbenormalizedoverarangeofthicknesswithoutproducingmisleadingdataastotheactualimpactresistanceofthematerial.Datafromthesetestmethodsarecomparableonlyforspecimensthatvarybynomorethanx00B1;25%fromthenominaloraveragethicknessofthespecimenstested.Severalimpacttestmethodsareusedforfilm.Itissometimesdesirabletoknowtherelationshipsamongtestresultsderivedbydifferenttestmethods.Astudywasconductedinwhichfourfilmsmadefromtworesins(polypropyleneandlinearlow-densitypolyethylene),withtwofilmthicknessesforeachresin,wereimpactedusingTestMethodsD1709(MethodA),D3420(ProceduresAandB),andD4272.ThetestresultsareshownintheAppendix.DifferencesinresultsbetweenTestMethodsD1709andD4272maybeexpectedsinceTestMethodsD1709representsfailureinitiatedenergy,whileTestMethodD4272isinitiationpluscompletionenergy.Somefilmsmayshowconsistencywhentheinitiationenergyisthesameasthetotalenergy.ThisstatementandthetestdataalsoappearinthesignificancesectionsandappendixesofTestMethodsD3420andD4272.1.1Thesetestmethodscoverthedeterminationoftheenergythatcausesplasticfilmtofailunderspecifiedconditionsofimpactofafree-fallingdart.Thisenergyisexpressedintermsoftheweight(mass)ofthemissilefallingfromaspecifiedheightwhichwouldresultin50%failureofspecimenstested.1.2Twotestmethodsaredescribed:1.2.1TestMethodAemploysadartwitha38.10x00B1;0.13-mm(1.500x00B1;0.005-in.)diameterhemisphericalheaddroppedfromaheightof0.66x00B1;0.01m(26.0x00B1;0.4in.).Thistestmethodmaybeusedforfilmswhoseimpactresistancesrequiremassesofabout50gorlesstoabout2kgtofracturethem.1.2.2TestMethodBemploysadartwitha50.80x00B1;0.13-mm(2.000x00B1;0.005-in.)diameterhemisphericalheaddroppedfromaheightof1.50x00B1;0.03m(60.0+0.25,x2212;1.70in.).Itsrangeofapplicabilityisfromabout0.3kgtoabout2kg.1.3Twotestingtechniquesaredescribed:1.3.1Thestandardtechniqueisthestaircasemethod.Bythistechnique,auniformmissileweightincrementisemployedduringte......
【中国标准分类号】:G33
【国际标准分类号】:83_140_10
【页数】:9P.;A4
【正文语种】:英语