ASTM E18-2018a andard Test Methods for Rockwell Hardness of Metallic Materials

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1、ThisinternationalstandardwasdevelopedinaccordancewithinternationallyrecognizedprinciplesonstandardizationestablishedintheDecisiononPrinciplesfortheDevelopmentofInternationalStandards,GuidesandRecommendationsissuedbytheWorldTradeOrganizationTechnicalBarrierstoTrade(TBT)Committee.Desi

2、gnation:E18−18aAnAmericanNationalStandardStandardTestMethodsfor1,2RockwellHardnessofMetallicMaterialsThisstandardisissuedundertheÞxeddesignationE18;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinpare

3、nthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(´)indicatesaneditorialchangesincethelastrevisionorreapproval.ThisstandardhasbeenapprovedforusebyagenciesoftheU.S.DepartmentofDefense.1.Scope*济南中船设备有限公司kilograms-force(kgf)andtheindenterballdiameterswerespeciÞedinunitsofinch

4、es(in.).ThisstandardspeciÞesthe1.1ThesetestmethodscoverthedeterminationoftheunitsofforceandlengthintheInternationalSystemofUnitsRockwellhardnessandtheRockwellsuperÞcialhardnessof(SI);thatis,forceinNewtons(N)andlengthinmillimetersmetallicmaterialsbytheRockwellindentationhardnessprin-

5、(mm).However,becauseofthehistoricalprecedentandciple.ThisstandardprovidestherequirementsforRockwellcontinuedcommonusage,forcevaluesinkgfunitsandballhardnessmachinesandtheproceduresforperformingRock-diametersininchunitsareprovidedforinformationandmuchwellhardnesstests.ofthediscussion

6、inthisstandardreferstotheseunits.1.2Thistestmethodincludesrequirementsfortheuseof1.6Thetestprinciples,testingprocedures,andveriÞcationportableRockwellhardnesstestingmachinesthatmeasureproceduresareessentiallyidenticalforboththeRockwellandRockwellhardnessbytheRockwellhardnesstestprin

7、cipleandRockwellsuperÞcialhardnesstests.ThesigniÞcantdifferencescanmeetalltherequirementsofthistestmethod,includingthebetweenthetwotestsarethatthetestforcesaresmallerforthedirectandindirectveriÞcationsofthetestingmachine.PortableRockwellhardnesstestingmachinesthatcannotmeetthedirect

8、RockwellsuperÞcialt