【英文标准名称】:StandardTestMethodforScratchHardnessofMaterialsUsingaDiamondStylus
【原文标准名称】:用金刚石触针测定材料划痕硬度的标准试验方法
【标准号】:ASTMG171-2003
【标准状态】:现行
【国别】:
【发布日期】:2003
【实施或试行日期】:
【发布单位】:美国材料与试验协会(US-ASTM)
【起草单位】:G02.30
【标准类型】:(TestMethod)
【标准水平】:()
【中文主题词】:
【英文主题词】:scratch;scratchhardness;single-pointabrasion;stylus
【摘要】:Thistestmethodisintendedtomeasuretheresistanceofsolidsurfacestopermanentdeformationundertheactionofasinglepoint(stylustip).Itisacompanionmethodtoquasi-statichardnesstestsinwhichastylusispressedintoasurfaceunderacertainnormalloadandtheresultantdepthorimpressionsizeisusedtocomputeahardnessnumber.Scratchhardnessnumbers,unlikequasi-statichardnessnumbers,involveadifferentcombinationofpropertiesofthesurfacebecausetheindenter,inthiscaseadiamondstylus,movestangentiallyalongthesurface.Therefore,thestressstateunderthescratchingstylusdiffersfromthatproducedunderaquasi-staticindenter.Scratchhardnessnumbersareinprincipleamoreappropriatemeasureofthedamageresistanceofamaterialtosurfacedamageprocessesliketwo-bodyabrasionthanarequasi-statichardnessnumbers.Thistestmethodisapplicabletoawiderangeofmaterials.Theseincludemetals,alloys,andsomepolymers.Themaincriteriaarethatthescratchingprocessproducesameasurablescratchinthesurfacebeingtestedwithoutcausingcatastrophicfracture,spallation,orextensivedelaminationofsurfacematerial.Severedamagetothetestsurface,suchthatthescratchwidthisnotclearlyidentifiableorthattheedgesofthescratcharechippedordistorted,invalidatestheuseofthistestmethodtodetermineascratchhardnessnumber.Sincethedegreeandtypeofsurfacedamageinamaterialmayvarywithappliedload,theapplicabilityofthistesttocertainclassesofmaterialsmaybelimitedbythemaximumloadatwhichvalidscratchwidthmeasurementscanbemade.Theresistanceofamaterialtoabrasionbyasinglepointmaybeaffectedbyitssensitivitytothestrainrateofthedeformationprocess.Therefore,thistestisconductedunderlowstylustraversingspeeds.Useofaslowscratchingspeedalsominimizesthepossibleeffectsoffrictionalheating.Thistestusesmeasurementsoftheresidualscratchwidthafterthestylushasbeenremovedtocomputethescratchhardnessnumber.Therefore,itreflectsthepermanentdeformationresultingfromscratchingandnottheinstantaneousstateofcombinedelasticandplasticdeformationofthesurface.1.1Thisstandarddescribeslaboratoryproceduresfordeterminingthescratchhardnessofthesurfacesofsolidmaterials.Withincertainlimitations,asdescribedinthisguide,thistestmethodisapplicabletometals,ceramics,polymers,andcoatedsurfaces.Thescratchhardnesstest,asdescribedherein,isnotintendedtobeusedasameanstodeterminecoatingadhesion,norisitintendedforusewithotherthanspecifichemispherically-tipped,conicalstyli.1.2Thisstandardmayinvolvehazardousmaterials,operations,andequipment.Thisstandarddoesnotpurporttoaddressallofthesafetyconcerns,ifany,associatedwithitsuse.Itistheresponsibilityoftheuserofthisstandardtoestablishappropriatesafetyandhealthpracticesanddeterminetheapplicabilityofregulatorylimitationspriortouse.
【中国标准分类号】:H22
【国际标准分类号】:17_040_20
【页数】:7P.;A4
【正文语种】: