AS 1683.15.2-1990 橡胶的测试方法15.2:硬度

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1AS1683.15.2—1990AustralianStandard®

MethodsoftestforelastomersMethod15.2:Durometerhardness

PREFACEThisStandardwaspreparedbytheStandardsAustraliaCommitteeonAnalysisandTestingofElastomersunderthedirectionofCommitteeRU/—,StandardsfortheRubberIndustrytosupersede,inpart,AS1683.15—1976,MethodsofTestforRubberPart15:IndentationHardnessofRubberandPlasticsbyMeansofaDurometer.

Thiseditioncorrectssomeerrorsinequationsandintroducesstandardrubbersasameansofverifyingdurometers.Atthesametime,theopportunityhasbeentakentointroducethedeadloadhardnessprocedurewhichisspecifiedinMethod15.1.

InthepreparationofthisStandard,accountwastakenofthefollowing:ISO48—1979Vulcanizedrubbers—Determinationofhardness(hardnessbetween30and85IRHD)

BS903—1969MethodsoftestingvulcanizedrubberPartA26:Determinationofhardness

2719—1975MethodsofuseandcalibrationofpockettyperubberhardnessmetersASTMD2240—1986Testmethodforrubberproperty—Durometerhardness

FOREWORDHardnessisdeterminedbythepenetrationofspecifiedindentorsintothematerialunderprescribedconditions.Themethodpermitsmeasurementofinitialindentationortheindentationafterspecifiedperiods,orboth.Theindentationhardnessisinverselyrelatedtothepenetrationoftheindentorandisdependentontheelasticmodulusandvisco-elasticbehaviourofthematerial.Theshapeoftheindentorandtheforceappliedtoitinfluencetheresultsobtainedandthustheremaybenosimplerelationshipbetweentheresultsobtainedusingthedifferenttypesofhardness-measuringinstruments.

Hardnessofelastomericmaterialsismeasuredonthreescales,asfollows:(a)InternationalRubberHardnessDegrees(IRHD),asusedinthedeadloadmethod(AS1683.15.1).

(b)DurometerHardnessDegrees,TypeA,usedformeasuringsoftermaterials(AS1683.15.2).

NOTE:Suchmaterialswouldhaveavalueapproximating30-90IRHD.(c)DurometerHardnessDegrees,TypeD,usedformeasuringhardermaterials(AS1683.15.2).

NOTE:Suchmaterialswouldhaveavalueabove90IRHD.NosimplerelationshipexistsbetweenindentationhardnessdeterminedbyAS1683.15.2andanyfundamentalpropertyofthematerialstested.

METHOD1SCOPEThismethodsetsouttheprocedurefordeterminingdurometerhardnessofelastomericmaterials.

Proceduresarealsogivenforverificationoftestingequipment.

COPYRIGHTAS1683.15.2—19902Thismethodusestwotypesofdurometers,TypeAandTypeD.TheTypeAdurometerisusedformeasuringelastomericmaterialsinthenormalhardnessrange(30-90IRHD)andTypeDforelastomericmaterialsinthehighhardnessrange(above90IRHD).

2PRINCIPLEHardnessisdeterminedbythepenetrationofspecifiedindentorsintothematerialunderprescribedconditions.

3REFERENCEDDOCUMENTSThefollowingdocumentsarereferredtointhisStandard:

AS1683Methodsoftestforrubber1683.15.1Method15.1:Internationalrubberhardness(IRHD).

ISO48Vulcanizedrubbers—Determinationofhardness(hardnessbetween30and85IRHD).

ASTMD2240Testmethodforrubberproperty—Durometerhardness

BS903MethodsoftestingvulcanizedrubberPartA26:Determinationofhardness

4APPARATUSAdurometerisrequired,whichshallconsistofthefollowingcomponents:

(a)APressorfoot—havingaholebetween2.5mmand3.2mmindiameter,centredatleast6mmfromanyedgeofthefoot.

(b)Indentor—formedfromhardenedsteelrod,ofbetween1.15mmand1.40mmindiameter,totheshapeanddimensionsshowninFigure1forTypeAdurometersorinFigure2forTypeDdurometers.

(c)Indicatingdevice—onwhichtheamountofextensionofthepointoftheindentormaybereadingraduationsrangingfrom0degreeshardnessforfullextensionof2.46mmto2.54mm,to100degreeshardnessforzeroextension.Zeroextensionisobtainedbyplacingthepressorfootandindentorinfirmcontactwithaflatpieceofglass.

NOTE:TypeA‘Shore’Durometersserialnumbers1to16300and16351to16900andtypeA-2‘Shore’Durometersnumbers1to8077donotmeettherequirementsof2.46mmto2.54mmextensionoftheindentorat0degreeshardnessreading.Thesedurometerswillgivereadingswhicharelowbyamountsrangingfrom3degreesat30degreeshardnessto1degreeat90degreeshardness.

(d)Acalibratedspring—forapplyingforcetotheindentorinaccordancewithoneofthefollowingequations:

(i)F=0.550+0.075HA4(1)whereFistheforce,innewtowns,andHAisthehardnessreadingonaTypeAdurometer.(ii)F=0.445HD4(2)whereFistheforce,innewtowns,andHDisthehardnessreadingonaTypeDdurometer.

5CALIBRATIONOFDUROMETERSBYMECHANICALMEANSThespringshallbecalibratedbymechanicalmeans.Thisisachievedbysupportingthedurometerinaverticalpositionandbyrestingthepointoftheindentoronasmallspaceratthecentreofonepanofabalance,asshowninFigure3,inordertopreventinterferencebetweenpressorfootandpan.Thespacershallhaveasmallcylindricalstemapproximately2.5mminheightand1.25mmindiameter,andshallbeslightlycuppedontoptoaccommodatetheindentorpoint.Themassofthespacermaybebalancedbyatareontheoppositepanofthebalance.Knownmassesmaybeaddedtotheoppositepantobalancetheforceontheindentoratvariousscalereadings.ThemeasuredforceshallequaltheforcecalculatedbyeitherEquation4(1)towithin±0.08N,orEquation4(2)towithin±0.44N.(SeeClause4(d).)