Designation:D6115−97(Reapproved2019)StandardTestMethodforModeIFatigueDelaminationGrowthOnsetofUnidirectionalFiber-ReinforcedPolymerMatrixComposites1ThisstandardisissuedunderthefixeddesignationD6115;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(´)indicatesaneditorialchangesincethelastrevisionorreapproval.1.Scope1.1Thistestmethoddeterminesthenumberofcycles(N)fortheonsetofdelaminationgrowthbasedontheopeningmodeIcyclicstrainenergyreleaserate(G),usingtheDoubleCantileverBeam(DCB)specimenshowninFig.1.Thistestmethodappliestoconstantamplitude,tension-tensionfatigueloadingofcontinuousfiber-reinforcedcompositematerials.WhenthistestmethodisappliedtomultiplespecimensatvariousG-levels,theresultsmaybeshownasaG–Ncurve,asillustratedinFig.2.1.2Thistestmethodislimitedtousewithcompositesconsistingofunidirectionalcarbonfibertapelaminateswithsingle-phasepolymermatrices.Thislimitedscopereflectstheexperiencegainedinroundrobintesting.Thistestmethodmayproveusefulforothertypesandclassesofcompositematerials,however,certaininterferenceshavebeennoted(seeSection6.5ofTestMethodD5528).1.3ThevaluesstatedinSIunitsaretoberegardedasstandard.Nootherunitsofmeasurementareincludedinthisstandard.1.3.1Exception—Thevaluesprovidedinparenthesesareforinformationonly.1.4Thisstandarddoesnotpurporttoaddressallofthesafetyconcerns,ifany,associatedwithitsuse.Itistheresponsibilityoftheuserofthisstandardtoestablishappro-priatesafety,health,andenvironmentalpracticesanddeter-minetheapplicabilityofregulatorylimitationspriortouse.1.5Thisinternationalstandardwasdevelopedinaccor-dancewithinternationallyrecognizedprinciplesonstandard-izationestablishedintheDecisiononPrinciplesfortheDevelopmentofInternationalStandards,GuidesandRecom-mendationsissuedbytheWorldTradeOrganizationTechnicalBarrierstoTrade(TBT)Committee.2.ReferencedDocuments2.1ASTMStandards:2D883TerminologyRelating...
