ASTM B761-2006 用X射线重力沉积监测法测定粉末和有关化合物的粒度分布的标准试验方法

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【英文标准名称】:StandardTestMethodforParticleSizeDistributionofMetalPowdersandRelatedCompoundsbyX-RayMonitoringofGravitySedimentation
【原文标准名称】:用X射线重力沉积监测法测定粉末和有关化合物的粒度分布的标准试验方法
【标准号】:ASTMB761-2006
【标准状态】:现行
【国别】:
【发布日期】:2006
【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】:B09.03
【标准类型】:(TestMethod)
【标准水平】:()
【中文主题词】:金属粉末;金属;粒度分布;放射性试验;高熔点金属;沉淀;试验
【英文主题词】:metalpowders;particlesize;particlesizedistribution;powderedmetals;refractorymetalpowders;sedimentationparticlesizedistribution
【摘要】:Thistestmethodisusefultobothsuppliersandusersofpowders,asoutlinedin1.1and1.2,indeterminingparticlesizedistributionforproductspecifications,manufacturingcontrol,development,andresearch.Usersshouldbeawarethatsampleconcentrationsusedinthistestmethodmaynotbewhatisconsideredidealbysomeauthorities,andthattherangeofthistestmethodextendsintotheregionwhereBrownianmovementcouldbeafactorinconventionalsedimentation.Withintherangeofthistestmethod,neitherthesampleconcentrationnorBrownianmovementarebelievedtobesignificant.Reportedparticlesizemeasurementisafunctionofboththeactualparticledimensionandshapefactoraswellastheparticularphysicalorchemicalpropertiesbeingmeasured.Cautionisrequiredwhencomparingdatafrominstrumentsoperatingondifferentphysicalorchemicalparametersorwithdifferentparticlesizemeasurementranges.Sampleacquisition,handling,andpreparationcanalsoaffectreportedparticlesizeresults.1.1Thistestmethodcoversthedeterminationofparticlesizedistributionsofmetalpowders.Experiencehasshownthatthistestmethodissatisfactoryfortheanalysisofelementaltungsten,tungstencarbide,molybdenum,andtantalumpowders,allwithanas-suppliedFishernumberof6morless,asdeterminedbyTestMethodB330.Othermetalpowders(forexample,elementalmetals,carbides,andnitrides)maybeanalyzedusingthistestmethodwithcautionastosignificanceuntilactualsatisfactoryexperienceisdeveloped(see).Theprocedurecoversthedeterminationofparticlesizedistributionofthepowderinthefollowingtwoconditions:1.1.1Asthepowderissupplied(as-supplied),and1.1.2AfterthepowderhasbeendeagglomeratedbyrodmillingasdescribedinPracticeB859.1.2Thistestmethodisapplicabletoparticlesofuniformdensityandcompositionhavingaparticlesizedistributionrangeof0.1upto100m.1.2.1However,therelationshipbetweensizeandsedimentationvelocityusedinthistestmethodassumesthatparticlessedimentwithinthelaminarflowregime.ThisrequiresthattheparticlessedimentwithaReynoldsnumberof0.3orless.ParticlesizedistributionanalysisforparticlessettlingwithalargerReynoldsnumbermaybeincorrectduetoturbulentflow.SomematerialscoveredbythistestmethodmaysettlewithReynoldsnumbergreaterthan0.3ifparticlesgreaterthan25marepresent.TheuserofthistestmethodshouldcalculatetheReynoldsnumberofthelargestparticleexpectedtobepresentinordertojudgethequalityofobtainedresults.Reynoldsnumber(Re)canbecalculatedusingtheflowingequationEquation1-Re=D3(-0)0g/182whereDthediameterofthelargestparticleexpectedtobepresent,theparticledensity,0thesuspendingliquiddensity,gtheaccelerationduetogravity,andisthesuspendingliquidviscosity.AtableofthelargestparticlesthatcanbeanalyzedwithReynoldsnumberof0.3orlessinwaterat35Cisgivenforanumberofmetalsin.AcolumnoftheReynoldsnumbercalculatedfora30-mparticlesedimentinginthesameliquidsystemisgivenforeachmaterialalso.Thisstandarddoesnotpurporttoaddressallofthesafetyconcerns,ifany,associatedwithitsuse.Itistheresponsibilityoftheuserofthisstandardtoestablishappropriatesafetyandhealthpracticesanddeterminetheapplicabilityofregulatorylimitationspriortouse.SpecifichazardinformationisgiveninSection7.
【中国标准分类号】:H26
【国际标准分类号】:77_160
【页数】:4P.;A4
【正文语种】: