【英文标准名称】:StandardTestMethodforPorosityinGoldorPalladiumCoatingsonMetalSubstratesbyGel-BulkElectrography
【原文标准名称】:凝胶体电谱法测定金属基物上金或钯涂层孔隙度的标准试验方法
【标准号】:ASTMB798-1995(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】:electrography;gel;gelelectrography;goldcoatings;goldplatings;palladiumcoatings;palladiumplatings;plating;porosity;porositytesting;Contamination--coatings;Corrosion--electrodepositedcoatings;Defects--coatings;Destructivetesting--coatin
【摘要】:Noblemetalcoatings,particularlygoldorpalladium,areoftenspecifiedforthecontactsofseparableelectricalconnectorsandotherdevices.Electrodepositsaretheformofgoldorpalladiumwhichismostusedoncontacts,althoughgoldandpalladiumarealsoemployedascladmetalandasweldmentsonthecontactsurface.Theintrinsicnobilityofgoldandtoacertainextentpalladiumenablesthemtoresisttheformationofinsulatingfilmsthatcouldinterferewithreliablecontactoperation.Inorderthatthenobilityofgoldbeassured,porosity,cracks,andotherdefectsinthecoatingthatexposebasemetalsubstratesandunderplatesmustbeminimalorabsent,exceptinthosecaseswhereitisfeasibletousethecontactsinstructuresthatshieldthesurfacefromtheenvironmentorwherecorrosioninhibitingsurfacetreatmentsforthedepositareemployed.Thelevelofporosityinthecoatingthatmaybetolerabledependsontheseverityoftheenvironmenttotheunderplateorsubstrate,designfactorsforthecontactdeviceliketheforcewithwhichitismated,circuitparameters,andthereliabilityofcontactoperationthatitisnecessarytomaintain.Also,whenpresent,thelocationofporesonthesurfaceisimportant.Iftheporesarefewinnumberorareoutsideofthezoneofcontactofthematingsurfaces,theirpresencecanoftenbetolerated.Methodsfordeterminingporesonacontactsurfacearemostsuitableiftheyenabletheirpreciselocationandnumberstobedetermined.Contactsurfacesareoftencurvedorirregularinshape,andtestingmethodsshouldbesuitableforthem.Inaddition,theseverityofporosity-determiningtestsmayvaryfromprocedurescapableofdetectingallporositytoproceduresthatdetectonlygrossdefects.Thetestmethodinthisdocumentisgenerallyregardedassevere.Therelationshipofporositylevelsrevealedbyparticularteststocontactbehaviormustbemadebytheuseroftheseteststhroughpracticalexperienceorjudgment.Thus,absenceofporosityinthecoatingmaybearequirementforsomeapplications,whileafewporesinthecontactzonemaybeacceptableforothers.Thistestmethodiscapableofdetectingporosityorotherdefectsingoldorpalladiumcoatingsthatcouldparticipateinsubstratecorrosionreactions.Inaddition,itcanbeusedoncontactshavingcomplexgeometrysuchaspin-socketcontacts(althoughdifficultymaybeexperiencedininspectingdeeprecesses).1.1Thistestmethodcoversequipmentandtechniquesfordeterminingporosityinnoblemetalcoatings,particularlyelectrodepositsandcladmetalsusedonelectricalcontacts.1.2Thetestmethodisdesignedtoshowwhethertheporositylevelislessorgreaterthansomevaluewhichbyexperienceisconsideredbytheusertobeacceptablefortheintendedapplication.1.3OtherporositytestingmethodsareoutlinedinGuideB765.Detailedcriticalreviewsofporositytestingarealsoavailable.OtherporositytestmethodsareB735,B741,B799,andB809.1.4ThevaluesstatedinSIunitsaretoberegardedasstandard.Thevaluesinparenthesesareforinformationonly.1.5Thisstandarddoesnotpurporttoaddressallofthesafetyconcerns,ifany,associatedwithitsuse.ItistheresponsibilityoftheuserofthisstandardtobecomefamiliarwithallhazardsincludingthoseidentifiedintheappropriateMaterialSafetyDataSheet(MSDS)forthisproduct/materialasprovidedbythemanufacturer,toestablishappropriatesafetyandhealthpractices,anddeterminetheapplicabilityofregulatorylimitationspriortouse.Forspecifichazardstatements,seeSections7and8.
【中国标准分类号】:A29
【国际标准分类号】:25_220_40
【页数】:6P.;A4
【正文语种】:英语