Standard Test Method for Measuring Damage Resistance of Fiber-Reinforced Polymer-Matrix Composite to Concentrated Quasi-Static Indentation Force

FIG.2TypicalFixturefortheSimplySupported

Con guration

valueofNshallbeused(N+1).Foratypical145-gradetape,a32-plyspecimenshallbemanufacturedwithalay-upof[45/0/ 45/90]4S.

8.2.1.2WovenFabric—Laminateconstructionshallconsistoftheappropriatenumberoffabricpliestoachieveatotalcuredthicknessnearestto4.2mm(0.17in.)withastackingsequenceof[(+45/ 45)/(0/90)]NSwhereNisawholenumber.Ifthe“nearest”thicknessislessthan3.5mm(0.14in.),thenextvalueofNshallbeused(N+1).Thedesignations(+45/ 45)and(0/90)representasinglelayerofwovenfabricwiththewarpandweft bersorientedatthespeci edangles.Ifasatinweaveisused,eachlayershallbe ippedsuchthatthepredominanttowdirectiononeachsideofthefabriccorre-spondstothespeci edlay-up.

8.3SpecimenDimensions—Specimensshallbe152.061.0mm(6.0060.05in.)squareandofconstantthickness.Thevariationinthicknessforanygivenspecimenshallnotexceed0.1mm.

8.4SpecimenPreparation—PanelsshallbefabricatedandmachinedinaccordancewithGuideD5687/belthecouponssothattheywillbedistinctfromeachotherandtraceablebacktotherawmaterial,andinamannerthatwillbothbeunaffectedbythetestandnotin uencethetest.

8.5VoidContentandFiberVolume—Itisrecommendedthatvoidcontentand bervolumebereported.VoidcontentmaybedeterminedusingtheequationsofTestMethodD2734.The bervolumefractionmaybedeterminedusingmatrixdigestionperTestMethodD3171.

9.Calibration

9.1Theaccuracyofallmeasuringequipmentshallhavecerti edcalibrationsthatarecurrentatthetimeofuseoftheequipment.

10.Conditioning

10.1StandardConditioningProcedure—Conditionspeci-meninaccordancewithProcedureCofTestMethodD5229/D5229Munlessotherconditioningisspeci edaspartoftheexperiment.StoreandtestspecimensatStandardLaboratoryAtmosphere(2363°C[7365°F]and50610%relativehumidity).Nonstandardconditioningandnonstandardtestenvironmentsshallbereported.

10.2OvenDrying—Ifdamageresistancedataaredesiredforlaminatesinanoven-driedcondition,useProcedureDofTestMethodD5229/D5229M.11.Procedure

11.1Selecteitherthesimplysupportedorrigidlybackedtestcon guration.Mounttheappropriate xture(s)inthetestingmachine.Thefollowingproceduresareidenticalforthetwotestcon gurations.Reportanydeviationsfromthistestmethod,whetherintentionalorinadvertent.

11.2If bervolumeorvoidcontentaretobereported,thenobtainthesesamplesfromthesamepanelbeingtested.

11.3Mounttheindenterinthetestingmachinesuchthattherelativedisplacementbetweenthespecimenandindenterwillbenormaltothefaceofthespecimen.

11.4Measurethethicknessofeachspecimentothenearest0.05mm(0.002in.)atseveralpointsaroundtheedgeofthespecimenusingamicrometer(7.7).Thevariationinthicknessalongthelengthofthespecimenshallnotexceed0.1mm(0.004in.).Theaveragevalueofthethicknessmeasurementsshallberecorded.

11.5Markthecenterofthespecimen’sface.Forthesimplysupportedcon guration,placethespecimenonthesupport xture,makingsurethatthespecimen’scenterisaligned

with