ASTM G32-2009 使用振动装置对气蚀侵蚀的试验方法

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【英文标准名称】:StandardTestMethodforCavitationErosionUsingVibratoryApparatus
【原文标准名称】:使用振动装置对气蚀侵蚀的试验方法
【标准号】:ASTMG32-2009
【标准状态】:现行
【国别】:美国
【发布日期】:2009
【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】:G02.10
【标准类型】:(TestMethod)
【标准水平】:()
【中文主题词】:
【英文主题词】:cavitation;cavitationerosion;erosionbyliquids;erosion-corrosion;erosionofsolids;erosionresistance;erosiontest;vibratorycavitation;Cavitationerosion/corrosion;Corrosion--cavitationerosion/corrosion;Dieselenginecylinderliners;Dynamom
【摘要】:Thistestmethodmaybeusedtoestimatetherelativeresistanceofmaterialstocavitationerosionasmaybeencountered,forinstance,inpumps,hydraulicturbines,hydraulicdynamometers,valves,bearings,dieselenginecylinderliners,shippropellers,hydrofoils,andininternalflowpassageswithobstructions.AnalternativemethodforsimilarpurposesisTestMethodG134,whichemploysacavitatingliquidjettoproduceerosiononastationaryspecimen.Thelattermaybemoresuitableformaterialsnotreadilyformedintoapreciselyshapedspecimen.Theresultsofeither,orany,cavitationerosiontestshouldbeusedwithcaution;see5.8.Someinvestigatorshavealsousedthistestmethodasascreeningtestformaterialssubjectedtoliquidimpingementerosionasencountered,forinstance,inlow-pressuresteamturbinesandinaircraft,missilesorspacecraftflyingthroughrainstorms.PracticeG73describesanothertestingapproachspecificallyintendedforthattypeofenvironment.Thistestmethodisnotrecommendedforevaluatingelastomericorcompliantcoatings,someofwhichhavebeensuccessfullyusedforprotectionagainstcavitationorliquidimpingementofmoderateintensity.Thisisbecausethecomplianceofthecoatingonthespecimenmayreducetheseverityoftheliquidcavitationinducedbyitsvibratorymotion.Theresultwouldnotberepresentativeofafieldapplication,wherethehydrodynamicgenerationofcavitationisindependentofthecoating.Note18212;Analternativeapproachthatusesthesamebasicapparatus,andisdeemedsuitableforcompliantcoatings,isthex201C;stationaryspecimenx201D;method.Inthatmethod,thespecimenisfixedwithintheliquidcontainer,andthevibratingtipofthehornisplacedincloseproximitytoit.Thecavitationx201C;bubblesx201D;inducedbythehorn(usuallyfittedwithahighlyresistantreplaceabletip)actonthespecimen.Whileseveralinvestigatorshaveusedthisapproach(seeX3.2.3),theyhavedifferedwithregardtostandoffdistancesandotherarrangements.Thestationaryspecimenapproachcanalsobeusedforbrittlematerialswhichcannotbeformedintoathreadedspecimennorintoadiscthatcanbecementedtoathreadedspecimen,asrequiredforthistestmethod(see7.6).Thistestmethodshouldnotbedirectlyusedtorankmaterialsforapplicationswhereelectrochemicalcorrosionorsolidparticleimpingementplaysamajorrole.However,adaptationsofthebasicmethodandapparatushavebeenusedforsuchpurposes(see9.2.5,9.2.6,andX3.2).GuideG119maybefollowedinordertodeterminethesynergismbetweenthemechanicalandelectrochemicaleffects.Thosewhoareengagedinbasicresearch,orconcernedwithveryspecializedapplications,mayneedtovarysomeofthetestparameterstosuittheirpurposes.However,adherencetothistestmethodinallotherrespectswillpermitabetterunderstandingandcorrelationbetweentheresultsofdifferentinvestigators.Becauseofthenonlinearnatureoftheerosion-versus-timecurveincavitationandliquidimpingementerosion,theshapeofthatcurvemustbeconsideredinmakingcomparisonsanddrawingconclusions.SeeSection11.Theresultsofthistestmaybesignificantlyaffectedbythespecimenx2019;ssurfacepreparation.Thismustbeconsideredinplanning,conductingandreportingatestprogram.Seealso7.4and12.2.Themechanismsofcavitationerosionandliquidimpingementerosionarenotfullyunderstoodandmaydiffer,dependingonthedetailednature,scale,andinte............
【中国标准分类号】:H25
【国际标准分类号】:77_060
【页数】:16P.;A4
【正文语种】:英语