【英文标准名称】:StandardTestMethodforDeterminingJ-RCurvesofPlasticMaterials
【原文标准名称】:测定塑料材料J-R曲线的标准试验方法
【标准号】:ASTMD6068-1996(2002)e1
【标准状态】:现行
【国别】:
【发布日期】:1996
【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】:D20.10
【标准类型】:(TestMethod)
【标准水平】:()
【中文主题词】:材料试验;聚合材料;塑料和橡胶技术
【英文主题词】:crackgrowthresistance;fracturetoughness;J-Rcurves;plastics;polymers
【摘要】:AJ-Rcurveproducedinaccordancewiththistestmethodcharacterizesthecrackgrowthresistancesofawiderangeoftoughpolymersandpolymerblends(1-5)7thatcannotbeobtainedinsufficientsizeandthicknessforvalidcharacterizationbylinearelasticfracturemechanicsinTestMethodsD5045.TheJ-Rcurvecharacterizes,withinthelimitssetforthinthistestmethod,theresistanceofapolymericmaterialtoslowstablecrackgrowthafterinitiationfromapreexistingsharpflaw.AJ-Rcurvecanbeusedasanindexofmaterialtoughnessforblendoralloydesign,materialselection,materialsprocessing,andqualityassurance(6).TheJ-RcurvesfrombendspecimensrepresentlowerboundestimatesofJcapacityasafunctionofcrackextension,andhavebeenobservedtobeconservativerelativetothoseobtainedfromspecimenconfigurationsundertensileloading.TheJ-Rcurvesforagivenmaterialofconstantmicrostructuretendtoexhibitlowerslope(flatter)withincreasingthickness.Thus,itisrecommendedthatthelargestpossiblespecimenwithrepresentativemicrostructurebeused.TheJ-Rcurvecanbeusedtoassessthestabilityofcracksinstructuresinthepresenceofductiletearing,withawarenessofthedifferencesthatmayexistbetweenlaboratorytestandfieldconditions.AJ-Rcurvemaydependontheorientationandpropagationofthecrackinrelationtotheanisotropyofthematerialwhichmaybeinducedbyspecimenfabricationmethods.Becauseofthepossibilityofratedependenceofcrackgrowthresistance,J-Rcurvescanbedeterminedatdisplacementratesotherthanthatspecifiedinthistestmethod(7).1.1ThistestmethodcoversthedeterminationoftheJ-integralversuscrackgrowthresistance(J-R)curvesforpolymericmaterials.1.2Thistestmethodisintendedtocharacterizetheslow,stablecrackgrowthresistanceofbend-typespecimensinsuchamannerthatitisgeometryinsensitivewithinlimitssetforthinthistestmethod.1.3Therecommendedspecimensarethethree-pointbend(SE(B))andpin-loadedcompacttension(C(T))specimens.Bothspecimenshavein-planedimensionsofconstantproportionalityforallsizes.Specimenconfigurationsotherthanthoserecommendedinthistestmethodmayrequiredifferentproceduresandvalidityrequirements.1.4Thistestmethoddescribesamultiplespecimenmethodthatrequiresopticalmeasurementofcrackextensionfromfracturesurfaces.Itisnotrecommendedforusewithmaterialsinwhichthecrackfrontcannotbedistinguishedfromadditionaldeformationprocessesinadvanceofthecracktip.1.5ThevaluesstatedinSIunitsaretoberegardedasthestandard.1.6Thisstandarddoesnotpurporttoaddressallofthesafetyconcerns,ifany,associatedwithitsuse.Itistheresponsibilityoftheuserofthisstandardtoestablishappropriatesafetyandhealthpracticesanddeterminetheapplicabilityofregulatorylimitationspriortouse.Note18212;ThereisnoequivalentISOstandard.
【中国标准分类号】:G31
【国际标准分类号】:83_040_01
【页数】:8P.;A4
【正文语种】: