Designation:D6068−10StandardTestMethodforDeterminingJ-RCurvesofPlasticMaterials1ThisstandardisissuedunderthefixeddesignationD6068;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(´)indicatesaneditorialchangesincethelastrevisionorreapproval.1.Scope1.1ThistestmethodcoversthedeterminationoftheJ-integralversuscrackgrowthresistance(J-R)curvesforpolymericmaterials.1.2Thistestmethodisintendedtocharacterizetheslow,stablecrackgrowthresistanceofbend-typespecimensinsuchamannerthatitisgeometryinsensitivewithinlimitssetforthinthistestmethod.1.3Therecommendedspecimensarethethree-pointbend(SE(B))andpin-loadedcompacttension(C(T))specimens.Bothspecimenshavein-planedimensionsofconstantpropor-tionalityforallsizes.Specimenconfigurationsotherthanthoserecommendedinthistestmethodmayrequiredifferentproce-duresandvalidityrequirements.1.4Thistestmethoddescribesamultiplespecimenmethodthatrequiresopticalmeasurementofcrackextensionfromfracturesurfaces.Itisnotrecommendedforusewithmaterialsinwhichthecrackfrontcannotbedistinguishedfromaddi-tionaldeformationprocessesinadvanceofthecracktip.1.5ThevaluesstatedinSIunitsaretoberegardedasthestandard.1.6Thisstandarddoesnotpurporttoaddressallofthesafetyconcerns,ifany,associatedwithitsuse.Itistheresponsibilityoftheuserofthisstandardtoestablishappro-priatesafetyandhealthpracticesanddeterminetheapplica-bilityofregulatorylimitationspriortouse.NOTE1—ThereisnoequivalentISOstandard.2.ReferencedDocuments2.1ASTMStandards:2D618PracticeforConditioningPlasticsforTestingD4066ClassificationSystemforNylonInjectionandExtru-sionMaterials(PA)D5045TestMethodsforPlane-StrainFractureToughnessandStrainEnergyReleaseRateofPlasticMaterialsE399TestMethodforLinear-ElasticPlane-StrainFractureToughnessKIcofMetallicMaterialsE616TerminologyRelatingtoFractureTesting(Discontin-ued1996)(Withdrawn1996)3E1152TestMethodforDetermining-J-R-Curve...
