Designation:B631−93(Reapproved2016)StandardSpecificationforSilver-TungstenElectricalContactMaterials1ThisstandardisissuedunderthefixeddesignationB631;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(´)indicatesaneditorialchangesincethelastrevisionorreapproval.1.Scope1.1Thisspecificationcoverselectricalcontactcomponentsmadefromsilver-tungstenbypowder-metallurgicalproce-dures.1.2Thisspecificationcoverscompositionswithinthesilver-tungstensystemnormallyspecifiedbyusersofcontacts.1.3Thisstandarddoesnotpurporttoaddressallofthesafetyconcerns,ifany,associatedwithitsuse.ItistheresponsibilityoftheuserofthisstandardtobecomefamiliarwithallhazardsincludingthoseidentifiedintheappropriateDataSafetySheet(SDS)forthisproduct/materialasprovidedbythemanufacturer,toestablishappropriatesafetyandhealthpractices,anddeterminetheapplicabilityofregulatorylimi-tationspriortouse.2.ReferencedDocuments2.1ASTMStandards:2B328TestMethodforDensity,OilContent,andIntercon-nectedPorosityofSinteredMetalStructuralPartsandOil-ImpregnatedBearings(Withdrawn2009)33.OrderingInformation3.1Ordersforthismaterialunderthisspecificationshallincludethefollowinginformation:3.1.1Dimensions(seeSection7).3.1.2Chemicalcomposition(seereferencetablesintheAppendixX1asapossibleguide).3.1.3Physicalproperties(seeSection6andAppendixX1asguideline).3.1.4Certification(seeSection13).3.1.5Otherfeaturesasagreeduponbetweenthepurchaserandmanufacturer.4.ChemicalComposition4.1Thematerialshallconformtocompositionlimitsasagreeduponbetweenthemanufacturerandpurchaser.4.2ThechemicalanalysisshallbemadeinaccordancewiththemethodsprescribedinthenewesteditionoftheAnnualBookofASTMStandards,orbyanyotherapprovedmethodagreeduponbetweenthemanufacturerandpurchaser.5.OtherRequirements5.1Themanufacturerandpurchasershallagreeonqualifi-cationtestsfordeterminationofphysicalproperties.5.2Thetestsshallbeperformed...
