ASTM-D2240-05-Rubber-Hardness

Designation:D2240–05StandardTestMethodforRubberProperty—DurometerHardness1ThisstandardisissuedunderthefixeddesignationD2240;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(e)indicatesaneditorialchangesincethelastrevisionorreapproval.ThisstandardhasbeenapprovedforusebyagenciesoftheDepartmentofDefense.1.Scope1.1Thistestmethodcoverstwelvetypesofrubberhardnessmeasurementdevicesknownasdurometers:TypesA,B,C,D,DO,E,M,O,OO,OOO,OOO-S,andR.Theprocedurefordeterminingindentationhardnessofsubstancesclassifiedasthermoplasticelastomers,vulcanized(thermoset)rubber,elas-tomericmaterials,cellularmaterials,gel-likematerials,andsomeplasticsisalsodescribed.1.2Thistestmethodisnotequivalenttootherindentationhardnessmethodsandinstrumenttypes,specificallythosedescribedinTestMethodD1415.1.3Thistestmethodisnotapplicabletothetestingofcoatedfabrics.1.4Allmaterials,instruments,orequipmentusedforthedeterminationofmass,force,ordimensionshallhavetrace-abilitytotheNationalInstituteforStandardsandTechnology,orotherinternationallyrecognizedorganizationsparallelinnature.1.5ThevaluesstatedinSIunitsaretoberegardedasstandard.Thevaluesgiveninparenthesesareforinformationonly.ManyofthestateddimensionsinSIaredirectconver-sionsfromtheU.S.CustomarySystemtoaccommodatetheinstrumentation,practices,andproceduresthatexistedpriortotheMetricConversionActof1975.1.6Thisstandarddoesnotpurporttoaddressallofthesafetyconcerns,ifany,associatedwithitsuse.Itistheresponsibilityoftheuserofthisstandardtoestablishappro-priatesafetyandhealthpracticesanddeterminetheapplica-bilityofregulatorylimitationspriortouse.2.ReferencedDocuments2.1ASTMStandards:2D374TestMethodsforThicknessofSolidElectricalInsu-lationD618PracticeforConditioningPlasticsforTestingD785TestMethodforRockwellHardnessofPlasticsandElectricalInsulatingMaterialsD1349PracticeforRubber—StandardTemperaturesforTestingD1415TestMethodforRubberProperty—InternationalHardnessD4483PracticeforDeterminingPrecisionforTestMethodStandardsintheRubberandCarbonBlackIndustriesF1957TestMethodforCompositeFoamHardness-DurometerHardness2.2ISOStandard:3ISO/IEC17025:1999GeneralRequirementsfortheCom-petenceofTestingandCalibrationLaboratories3.SummaryofTestMethod3.1Thistestmethodpermitshardnessmeasurementsbasedoneitherinitialindentationorindentationafteraspecifiedperiodoftime,orboth.Durometerswithmaximumreadingindicatorsusedtodeterminemaximumhardnessvaluesofamaterialmayyieldlowerhardnesswhenthemaximumindi-catorisused.3.2TheproceduresforTypeM,ormicrohardnessdurom-eters,accommodatespecimensthatare,bytheirdimensionsorconfiguration,ordinarilyunabletohavetheirdurometerhard-nessdeterminedbytheotherdurometertypesdescribed.TypeMdurometersareintendedforthetestingofspecimenshavingathicknessorcross-sectionaldiameterof1.25mm(0.050in.)orgreater,althoughspecimensoflesserdimensionsmaybesuccessfullyaccommodatedundertheconditionsspecifiedinSection6,andhaveaTypeMdurometerhardnessrangebetween20and90.Thosespecimenswhichhaveadurometerhardnessrangeotherthanspecifiedshalluseanothersuitableprocedurefordeterminingdurometerhardness.4.SignificanceandUse4.1Thistestmethodisbasedonthepenetrationofaspecifictypeofindentorwhenforcedintothematerialunderspecifiedconditions.Theindentationhardnessisinverselyrelatedtothepenetrationandisdependentontheelasticmodulusandviscoelasticbehaviorofthematerial.Thegeometryofthe1ThistestmethodisunderthejurisdictionofASTMCommitteeD11onRubberandisthedirectresponsibilityofSubcommitteeD11.10onPhysicalTesting.CurrenteditionapprovedAug.15,2005.PublishedSeptember2005.Originallyapprovedin1964.Lastpreviouseditionapprovedin2004asD2240–04e1.2ForreferencedASTMstandards,visittheASTMwebsite,@astm.org.ForAnnualBookofASTMStandardsvolumeinformation,refertothestandard’sDocumentSummarypageontheASTMwebsite.3AvailablefromInternationalOrganizationforStandardization(ISO),1ruedeVarembé,Casepostale56,CH-1211,Geneva20,Switzerland.1Copyright©ASTMInternational,100BarrHarborDrive,POBoxC700,WestConshohocken,PA19428-2959,UnitedStates.CopyrightbyASTMInt'l(allrightsreserved);ThuMar2003:21:00EST2008Downloaded/printedbyFordpursuanttoLicenseAgreement.Nofurtherreproductionsauthorized.indentorandtheappliedforceinfluencethemeasurementssuchthatnosimplerelationshipexistsbetweenthemeasure-mentsobtainedwithonetypeofdurometerandthoseobtainedwithanothertypeofdurometerorotherinstrumentsusedformeasuringhardness.Thistestmethodisanempiricaltestintendedprimarilyforcontrolpurposes.Nosimplerelationshipexistsbetweenindentationhardnessdeterminedbythistestmethodandanyfundamentalpropertyofthematerialtested.Forspecificationpurposes,itisrecommendedthatTestMethodD785beusedformaterialsotherthanthosedescribedin1.1.5.Apparatus5.1HardnessMeasuringApparatus,orDurometer,andanOperatingStand,Type1,Type2,orType3(see5.1.2)consistingofthefollowingcomponents:5.1.1Durometer:5.1.1.1PresserFoot,theconfigurationandthetotalareaofadur