Designation:B520−12(Reapproved2017)StandardSpecificationforTin-Coated,Copper-CladSteelWireforElectronicApplication1ThisstandardisissuedunderthefixeddesignationB520;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(´)indicatesaneditorialchangesincethelastrevisionorreapproval.ThisstandardhasbeenapprovedforusebyagenciesoftheU.S.DepartmentofDefense.1.Scope1.1Thisspecificationcoverstin-coatedcopper-cladsteelwireforelectronicapplication.1.2Fourclassesoftin-coatedcopper-cladsteelwirearecoveredasfollows:1.2.1ClassT30HS—Nominal30%conductivity,hard-drawn,1.2.2ClassT30A—Nominal30%conductivity,annealed,1.2.3ClassT40HS—Nominal40%conductivity,hard-drawn,and1.2.4ClassT40A—Nominal40%conductivity,annealed.1.3Thevaluesstatedininch-poundunitsaretoberegardedasstandard.ThevaluesgiveninparenthesesaremathematicalconversionstoSIunitsthatareprovidedforinformationonlyandarenotconsideredstandard.1.3.1Exception—TheSIvaluesforresistivityandvolumearetoberegardedasstandard.1.4Thefollowingsafetyhazardscaveatpertainsonlytothetestmethodportion,Section6,ofthisspecification:Thisstandarddoesnotpurporttoaddressallofthesafetyconcerns,ifany,associatedwithitsuse.Itistheresponsibilityoftheuserofthisstandardtoestablishappropriatesafetyandhealthpracticesanddeterminetheapplicabilityofregulatorylimita-tionspriortouse.(Warning—Considerationshouldbegiventotoxicityandflammabilitywhenselectingsolventcleaners.)1.5Thisinternationalstandardwasdevelopedinaccor-dancewithinternationallyrecognizedprinciplesonstandard-izationestablishedintheDecisiononPrinciplesfortheDevelopmentofInternationalStandards,GuidesandRecom-mendationsissuedbytheWorldTradeOrganizationTechnicalBarrierstoTrade(TBT)Committee.2.ReferencedDocuments2.1Thefollowingdocumentsoftheissueineffectondateofmaterialpurchaseformapartofthisspecificationtotheextentreferencedherein:2.2ASTMStandards:2B193TestMethodf...
