ASTM-B579-73(2004)-锡铅合金的电解沉积镀层(焊接板)

Designation:B579–73(Reapproved2004)StandardSpecificationforElectrodepositedCoatingsofTin-LeadAlloy(SolderPlate)1ThisstandardisissuedunderthefixeddesignationB579;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(e)indicatesaneditorialchangesincethelastrevisionorreapproval.ThisstandardhasbeenapprovedforusebyagenciesoftheDepartmentofDefense.1.Scope1.1Thisspecificationcoverstherequirementsforelectrode-positedtin-leadcoatingsonfabricatedarticlesofiron,steel,copper,andcopperalloys,toprotectthemagainstcorrosion(Note1),toimproveandpreservesolderabilityoverlongperiodsofstorage,andtoimproveanti-gallingcharacteristics.NOTE1—Somecorrosionoftin-leadcoatingsmaybeexpectedinoutdoorexposure.Innormalindoorexposure,tin-leadisprotectiveoniron,copper,andcopperalloys.Corrosionmaybeexpectedatdisconti-nuities(pitsorpores)inthecoating.Porositydecreasesasthethicknessisincreased.Aprimaryuseofthetin-leadcoating(solder)iswiththeprintedcircuitindustryasasolderablecoatingandasanetchmaskmaterial.1.2Thisspecificationappliestoelectrodepositedcoatingscontainingaminimumof50%andamaximumof70%tin.Thespecificationappliestomat,bright,andflow-brightenedtin-leadcoatings.NOTE2—Tin-leadplatingbathsarecomposedoftinandleadfluobo-ratesandofadditionagentstopromotestability.Thefinalappearancemaybeinfluencedbytheadditionofproprietarybrighteners.Withoutbright-eners,thecoatingsaremat;withbrighteners,theyaresemibrightorbright.Flow-brightenedcoatingsareobtainedbyheatingmatcoatingstoabovethemeltingpointoftin-leadforafewsecondsandthenquenching;palmoil,hydrogenatedoils,orfatsareusedasaheat-transfermediumatatemperatureof260610°C(500620°F),butothermethodsofheatingarealsoinuse.Themaximumthicknessforflow-brighteningisabout7.5μm(0.3mil);thickercoatingstendtoreflowunevenly.Theshapeofthepartisalsoafactor;flatsurfacestendtoreflowmoreunevenlythanwiresorroundedshapes(Note3).NOTE3—Volatileimpuritiesintin-leadcoatingswillcausebubblingandfoamingduringflow-brighteningresultinginvoidsandroughness.Theimpuritiescanarisefromplatingsolutionadditionagentsandfromimproperrinsingandprocessing.1.3Thisspecificationdoesnotapplytosheet,strip,orwireintheunfabricatedformortothreadedarticleshavingbasicmajordiametersuptoandincluding19mm(0.75in.).2.ReferencedDocuments2.1ASTMStandards:2B183PracticeforPreparationofLow-CarbonSteelforElectroplatingB242GuideforPreparationofHigh-CarbonSteelforElectroplatingB281PracticeforPreparationofCopperandCopper-BaseAlloysforElectroplatingandConversionCoatingsB322PracticeforCleaningMetalsPriortoElectroplatingB487TestMethodforMeasurementofMetalandOxideCoatingThicknessesbyMicroscopicalExaminationofaCrossSectionB499TestMethodforMeasurementofCoatingThicknessbytheMagneticMethod:NonmagneticCoatingsonMag-neticBasisMetalsB504TestMethodforMeasurementofThicknessofMetalCoatingsbytheCoulometricMethodB567TestMethodforMeasurementofCoatingThicknessbytheBetaBackscatterMethodB568TestMethodforMeasurementofCoatingThicknessbyX-RaySpectrometryE105PracticeforProbabilitySamplingofMaterialsE122PracticeforCalculatingSampleSizetoEstimate,WithaSpecifiedTolerableError,theAverageforCharac-teristicofaLotorProcess2.2OtherStandards:MIL-STD-105SamplingProceduresandTablesforInspec-tionbyAttributes3MIL-STD-414SamplingProceduresandTablesforInspec-tionbyVariablesforPercentDefective33.ClassificationandServiceCondition3.1Ordersforarticlestobeplatedinaccordancewiththisspecificationshallspecify,inadditiontotheASTMdesignation1ThisspecificationisunderthejurisdictionofASTMCommitteeB08onMetallicandInorganicCoatingsandisthedirectresponsibilityofSubcommitteeB08.08.04onSoftMetals.CurrenteditionapprovedApril1,2004.PublishedApril2004.Originallyapprovedin1973.Lastpreviouseditionapprovedin1999asB579–73(1999).2ForreferencedASTMstandards,visittheASTMwebsite,@astm.org.ForAnnualBookofASTMStandardsvolumeinformation,refertothestandard’sDocumentSummarypageontheASTMwebsite.3AvailablefromStandardizationDocumentsOrderDesk,Bldg.4SectionD,700RobbinsAve.,Philadelphia,PA19111-5094,Attn:NPODS.1Copyright©ASTMInternational,100BarrHarborDrive,POBoxC700,WestConshohocken,PA19428-2959,UnitedStates.numberandyearofissue,theclassificationnotationindicatingthebasismetalandthicknessoftin-leadcoatingrequired,ortheserviceconditionnumberindicatingtheseverityofservicerequiredforthecoating.Inaddition,whenspecifyingatin-leadcoatingcomposition,thefirstnumbershallrefertothetincontentinpercent.3.1.1ClassificationNotation:SymbolClassificationFe/IronorsteelbasismetalsCu/Copperorcopperalloybasismetals/Sn-PbTin-leadcoatinganditscompositionnumber,whenre-quired;forexample,Sn60-Pb40NumberMinimumcoatingthicknessinmicrometres(5to50)SuffixLetterfflow-brightenedbbrightmmatAnexampleofcompleteclassificationnotationisasfollows:Cu/Sn60-Pb40/5F3.1.2ServiceConditionNumber:No.ServiceCondition4verysevereexposure3severeexposure2moderateexposure1mildexposureNOTE4—SeeAppendixX1foradditionaldescriptionofe