ASTM B731–96R01

Designation: B 731 – 96 (Reapproved 2001) Standard Specification for 60 % Palladium-40 % Silver Electrical Contact Material 1 This standard is issued under the fixed designation B 731; the number immediately following the designation indicates the year of original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A superscript 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. Scope 1.1 This specification covers 60 % palladium-40 % silver rod, wire, strip, and sheet material for electrical contacts. 2. Referenced Documents 2.1 ASTM Standards: B 476 Specification for General Requirements forWrought Precious Metal Electrical Contact Materials 2 3. Manufacture 3.1 Raw materials shall be of such quality and purity that the finished product will have the properties and characteristics prescribed in this specification. 3.2 The material shall be finished by such operations (cold working, heat treating, annealing, turning, grinding, or pick- ling) as are required to produce the prescribed properties. 4. Chemical Requirements 4.1 Material produced under this specification shall meet the requirements for chemical composition prescribed in Table 1, in accordance with the practices prescribed in Specification B 476. 4.2 Uniformity of composition shall be assured by the use of good commercial preparation practices. 5. Mechanical Requirements 5.1 The contract or order may specify ultimate tensile strength, elongation, microhardness (Knoop or Vickers), or a combination of these mechanical properties (as listed in Table 2 or Table 3) as temper criterion. If the contract or order does not specify a temper criterion, then the criterion for temper designation will be ultimate tensile strength. 5.2 All test specimens shall be full thickness or diameter when practical. 5.3 All tests are to be conducted at room temperature, about 68°F (20°C). 6. Inspection and Testing 6.1 Material furnished under this specification shall be inspected by the manufacturer in accordance with Specification B 476. 7. Keywords 7.1 clad materials; contact material; palladium alloy; pre- cious metal; silver alloy1 This specification is under the jurisdiction of ASTM Committee B02 on Nonferrous Metals and Alloys and is the direct responsibility of Subcommittee B2.05 on Precious Metals and Electrical Contact Materials. Current edition approved May 10, 1996. Published July 1996. Originally published as B 731 – 84. Last previous edition B 731 – 91. 2 Annual Book of ASTM Standards, Vol 02.04. TABLE 1 Chemical Composition Element Weight Pd (by difference) 59.5 % min. Ag 39.1 to 40.5 % Cu 0.1 max Total other noble metals A 0.2 max Other Impurities: Individual elements B 0.01 max Collective total 0.10 max A Other noble metals are Au, Pt, Rh, Ir, Ru, and Os. BTypical metals are as indicated: Pb, Sn, Zn, Fe, Si, Mg, Ca, Al, Ni, Cr, Mn, Sb, B, Co, Mo, and Te, Cd, and In. 1 Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States. APPENDIX (Nonmandatory Information) X1. TYPICAL PROPERTY VALUES X1.1 The following is a list of typical property values that are useful for engineering calculations in electrical contact design and application. Electrical conductivity, % IACS Resistivity,V· cmil/ft 4 258 Microhm·cm 43 Solidus temperature, °C 1290 Liquidus temperature, °C 1340 Density: g/cm 3 11.35 tr oz/in. 3 5.98 ASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentioned in this standard. 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TABLE 2 Mechanical Properties of Sheet and Strip Temper Reduction in B&S Numbers (Reference) Percent Reduction (Reference) Ultimate Tensile Strength, psi (MPa) Minimum Elonga- tion in 2 in., % Typical Microhardness HK 100gmin max A 0 0 50 000 (344) 80 000 (551) 30 120 1 / 2 H 2 21 70 000 (482) 90 000 (620) 2 170 Hard 4 37 80 000 (551) 100 000 (180) 1 180 Spring 8 60 90 000 (620) 120 000 (827) ... 200 TABLE 3 Mechanical Properties of Wire, Rod, and Tubing Temper Reduction in B&S Numbers (Reference) Percent Reduction (Reference) Ultimate Tensile Strength, psi (MPa) Minimum Elonga- tion in 2 in., % Knoop Hardness (25 g, load) min max A 0 0 40 000 (275) 60 000 (414) 25 A 90–120 1 / 8 H 1 / 2 11 60 000 (414) 70 000 (482) 2 120–140 1 / 4 H 1 21 70 000 (482) 80 000 (551) 1 140–160 1 / 2 H 2 37 80 000 (551) 90 000 (620) 1 160–200 Hard 4 60 90 000 (620) 100 000 (689) 1 200–240 AWire in sizes less than 0.020 in. (0.5 mm) diameter and tubing of less than 0.010 in. (0.25 mm) wall thickness may be down to 15 %. B 731 2 主营业务范围：ASTMASTMASTMASTM、NASNASNASNAS、NASMNASMNASMNASM、MILMILMILMIL、ISOISOISOISO、ENENENEN、 DINDINDINDIN、JISJISJISJIS等技术 标准 excel标准偏差excel标准偏差函数exl标准差函数国标检验抽样标准表免费下载红头文件格式标准下载 翻译；技术资料翻译；NADCAPNADCAPNADCAPNADCAP认证 标准资料翻译；国外技术标准中文版优惠低价代购等。 业务 QQQQQQQQ：2298175560229817556022981755602298175560 专业 专注于技术翻译 诚信 实惠 物超所值的服务可靠的质量保证