1、Designation: B 628 98 (Reapproved 2004)Standard Specification forSilver-Copper Eutectic Electrical Contact Alloy1This standard is issued under the fixed designation B 628; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of
2、 last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.This standard has been approved for use by agencies of the Department of Defense.1. Scope1.1 This specification covers 72 % silv
3、er-28 % copper (eu-tectic) alloy rod, wire, strip, and sheet material for electricalcontacts.1.2 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibility of the user of this standard to become familiarwith all hazards including tho
4、se identified in the appropriateMaterial Safety Data Sheet for this product/material as pro-vided by the manufacturer, to establish appropriate safety andhealth practices, and determine the applicability of regulatorylimitations prior to use.2. Referenced Documents2.1 ASTM Standards:2B 277 Test Meth
5、od for Hardness of Electrical ContactMaterialsB 476 Specification for General Requirements for WroughtPrecious Metal Electrical Contact Materials3. General Requirements3.1 Specification B 476 and Test Method B 277 shall applyto all materials produced to this specification.4. Manufacture4.1 Raw mater
6、ials shall be of such quality and purity thatthe finished product will have the properties and characteristicsprescribed in this specification.4.2 The material shall be finished by such operations (coldworking, heat treating, annealing, turning, grinding, or pick-ling) as are required to produce the
7、 prescribed properties.5. Chemical Composition5.1 Material produced under the specification shall conformto the requirements as to chemical composition prescribed inTable 1.6. Mechanical Requirements6.1 The material shall conform to the mechanical propertiesprescribed in Table 2 or Table 3.6.2 All t
8、est specimens shall be full thickness or diameterwhen practical.6.3 All tests are to be conducted at room temperature, about68F (20C).7. Inspection and Testing7.1 Material furnished under this specification shall beinspected by the manufacturer as detailed in the applicableprovisions of Specificatio
9、n B 476 and as listed below.7.1.1 Visual inspection at 10 3.7.1.2 Temper test (hardness or tension, but not both). Atension test is recommended for strip below 0.030-in. (0.8-mm)thickness and for wire of any diameter. A tension test ispreferred when permitted by part size and quantity.7.1.3 Dimensio
10、nal tests.1This specification is under the jurisdiction of ASTM Committee B02 onNonferrous Metals and Alloys and is the direct responsibility of SubcommitteeB02.05 on Precious Metals and Electrical Contact Materials.Current edition approved May 1, 2004. Published May 2004. Originallyapproved in 1977
11、. Last previous edition approved in 1998 as B 628 98.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.TABLE 1
12、Chemical CompositionAElement Weight %Silver 71.0 to 73.0Copper balanceTotal of all impurities 0.15Zinc 0.06 maxIron 0.05 maxCadmium 0.05 maxLead 0.03 maxNickel 0.01 maxAluminum 0.005 maxPhosphorus 0.03 maxTotal others 0.06 maxAAnalysis is regularly made for the elements for which specific limits are
13、 listed.If, however, the presence of “other” elements is suspected or indicated in thecourse of routine analysis, further analysis shall be made to determine that thetotal of these “other” elements and the listed impurities are not in excess of the totalimpurities limit.1Copyright ASTM International
14、, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.7.1.4 Spectrographic or chemical analysis when indicatedby the purchase order.8. Keywords8.1 composition; electrical contacts; impurities; preciousmetals; silver copper alloyTABLE 2 Mechanical Properties of Sheet and StripTemperReduction inB or through the ASTM website(www.astm.org).3Available from Standardization Documents Order Desk, DODSSP, Bldg. 4,Section D, 700 Robbins Ave., Philadelphia, PA 19111-5098B 628 98 (2004)3
