BS EN 60335-2-90-2003 家用和类似用途电器的安全规范.特殊要求.商用微波炉的特殊要求

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【英文标准名称】:StandardTestMethodforPorosityinGoldandPalladiumCoatingsbySulfurousAcid/Sulfur-DioxideVapor
【原文标准名称】:用亚硫酸/SO2蒸汽测试金和钯镀层孔隙度的标准试验方法
【标准号】:ASTMB799-1995(2009)
【标准状态】:现行
【国别】:美国
【发布日期】:1995
【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】:B02.11
【标准类型】:(TestMethod)
【标准水平】:()
【中文主题词】:
【英文主题词】:goldcoatings;goldplatings;palladiumcoatings;palladiumplatings;platingporosity;porecorrosiontest;porositytesting;sulfurdioxidetest;sulfurousacid/SO2test;Contactsurfaces;Contamination--coatings;Corrosion--electrodeposited
【摘要】:Goldcoatingsareoftenspecifiedforthecontactsofseparableelectricalconnectorsandotherdevices.Electrodepositsaretheformofgoldthatismostusedoncontacts,althoughitisalsoemployedasinlayorcladmetalandasweldmentsonthecontactsurface.Theintrinsicnobilityofgoldenablesittoresisttheformationofinsulatingoxidefilmsthatcouldinterferewithreliablecontactoperation.Palladiumcoatingsaresometimesspecifiedasalternativestogoldonelectricalcontactsandsimilarelectricalcomponentsurfaces,bothaselectrodepositsandasinlayorcladmetal.Thistestmethodisparticularlysuitablefordeterminingporosityinpalladiumcoatings,sincethereactiveatmospherethatisuseddoesnotattackthepalladiumifthespecifiedtestconditionsarefollowed.Incontrast,palladiumcoatingsareattackedbynitricacid(HNO3)andotherstrongoxidizingagents,sothatTestMethodB735cannotbeusedfordeterminingtheporosityinsuchcoatings.Inorderforthesecoatingstofunctionasintended,porosity,cracks,andotherdefectsinthecoatingthatexposebase-metalsubstratesandunderplatesmustbeminimalorabsent,exceptinthosecaseswhereitisfeasibletousethecontactsinstructuresthatshieldthesurfacefromtheenvironmentorwherecorrosioninhibitingsurfacetreatmentsforthedepositareemployed.Thelevelofporosityinthecoatingthatmaybetolerabledependsontheseverityoftheenvironmenttotheunderplateorsubstrate,designfactorsforthecontactdeviceliketheforcewithwhichitismated,circuitparameters,andthereliabilityofcontactoperationthatitisnecessarytomaintain.Also,whenpresent,thelocationofporesonthesurfaceisimportant.Iftheporesarefewinnumberandareoutsideofthezoneofcontactofthematingsurfaces,theirpresencecanoftenbetolerated.Methodsfordeterminingporesonacontactsurfacearemostsuitableiftheyenabletheirpreciselocationandnumberstobedetermined.Contactsurfacesareoftencurvedorirregularinshape,andtestingmethodsshouldbesuitableforthem.Inaddition,theseverityofporosity-determiningtestsmayvaryfromprocedurescapableofdetectingallporositytoproceduresthatdetectonlyhighlyporousconditions.Thepresenttestmethodiscapableofdetectingvirtuallyallporosityorotherdefectsthatcouldparticipateincorrosionreactionswiththesubstrateorunderplate.Thetestisrapid,simple,andinexpensive.Inaddition,itcanbeusedoncontactshavingcomplexgeometrysuchaspin-socketcontacts(althoughwithdeeprecessesitispreferredthatthecontactstructuresbeopenedtopermitreactionofthesulfurdioxidewiththeinteriorsignificantsurfaces).Therelationshipofporositylevelsrevealedbyparticularteststocontactbehaviormustbemadebytheuseroftheseteststhroughpracticalexperienceorbyjudgment.Thus,absenceofporosityinthecoatingmaybearequirementforsomeapplications,whileafewporesinthecontactzonemaybeacceptableforothers.Thistestisconsidereddestructiveinthatitrevealsthepresenceofporositybycontaminatingthesurfacewithcorrosionproductsandbyundercuttingthecoatingatporesitesorattheboundariesoftheunplatedareas.Anypartsexposedtothistestshallnotbeplacedinservice.Thistestisintendedtobeusedforquantitativedescriptionsofporosity(suchasnumberofporesperunitareaorpercontact)onlyoncoatingsthathaveaporedensitysufficientlylowthatthecorrosionsitesarewellseparatedandcanbereadilyresolved.Asageneralguidelinethiscanbeachievedforporedensitiesuptoabout100/cm2.Abovethisvaluethetestsareusefulforthequalitativedetectionandcomparisonsofporosity.Forthesepurposes,themeasurementarea【英文标准名称】:Peakprogrammemeterforelectroacusticwidebandtransmission
【原文标准名称】:电声宽带传播用控制仪
【标准号】:DIN45406-1966
【标准状态】:作废
【国别】:德国
【发布日期】:1966-11
【实施或试行日期】:
【发布单位】:德国标准化学会(DIN)
【起草单位】:
【标准类型】:()
【标准水平】:()
【中文主题词】:输入阻抗;宽频带传输;饱和度控制;监督(认可);放大器;特性;峰值音量表;频率响应;公差;动力学;仪表刻度
【英文主题词】:properties;frequencyresponse;levelcontrols;widebandtransmission;instrumentscales;inputimpedance;surveillance(approval);tolerances(measurement);amplifiers;dynamics;peakprogrammemeters
【摘要】:
【中国标准分类号】:M72
【国际标准分类号】:2090
【页数】:2P;A4
【正文语种】:德语