1、Designation: B731 96 (Reapproved 2012)Standard Specification for60 % Palladium-40 % Silver Electrical Contact Material1This standard is issued under the fixed designation B731; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the ye
2、ar of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () 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 60 %
3、palladium-40 % silverrod, wire, strip, and sheet material for electrical contacts.1.2 The values stated in inch-pound units are to be regardedas standard. The values given in parentheses are mathematicalconversions to SI units that are provided for information onlyand are not considered standard.1.3
4、 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 those identified in the appropriateMaterial Safety Data Sheet (MSDS) for this product/materialas pr
5、ovided by the manufacturer, to establish appropriatesafety and health practices, and determine the applicability ofregulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2B476 Specification for General Requirements for WroughtPrecious Metal Electrical Contact Materials3. Manuf
6、acture3.1 Raw materials shall be of such quality and purity thatthe finished product will have the properties and characteristicsprescribed in this specification.3.2 The material shall be finished by such operations (coldworking, heat treating, annealing, turning, grinding, or pick-ling) as are requ
7、ired to produce the prescribed properties.4. Chemical Requirements4.1 Material produced under this specification shall meet therequirements for chemical composition prescribed in Table 1,in accordance with the practices prescribed in SpecificationB476.4.2 Uniformity of composition shall be assured b
8、y the use ofgood commercial preparation practices.5. Mechanical Requirements5.1 The contract or order may specify ultimate tensilestrength, elongation, microhardness (Knoop or Vickers), or acombination of these mechanical properties (as listed in Table2 or Table 3) as temper criterion. If the contra
9、ct or order doesnot specify a temper criterion, then the criterion for temperdesignation will be ultimate tensile strength.5.2 All test specimens shall be full thickness or diameterwhen practical.5.3 All tests are to be conducted at room temperature, about68F (20C).6. Inspection and Testing6.1 Mater
10、ial furnished under this specification shall beinspected by the manufacturer in accordance with SpecificationB476.7. Keywords7.1 clad materials; contact material; palladium alloy; pre-cious metal; silver alloy1This specification is under the jurisdiction of ASTM Committee B02 onNonferrous Metals and
11、 Alloys and is the direct responsibility of SubcommitteeB02.05 on Precious Metals and Electrical Contact Materials.Current edition approved May 1, 2012. Published May 2012. Originallyapproved in 1996. Last previous edition approved in 2006 as B731 96 (2006).DOI: 10.1520/B0731-96R12.2For referenced A
12、STM 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 Chemical CompositionElement WeightPd (by difference) 59.5 % min.Ag 39.
13、1 to 40.5 %Cu 0.1 maxTotal other noble metalsA0.2 maxOther Impurities:Individual elementsB0.01 maxCollective total 0.10 maxAOther 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.1Copyright ASTM
14、 International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.APPENDIX(Nonmandatory Information)X1. TYPICAL PROPERTY VALUESX1.1 The following is a list of typical property values thatare useful for engineering calculations in electrical contactdesign and applica
15、tion.Electrical conductivity, % IACSResistivity,V cmil/ft4258Microhmcm 43Solidus temperature, C 1290Liquidus temperature, C 1340Density:g/cm311.35tr oz/in.35.98ASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentionedin this stan
16、dard. Users of this standard are expressly advised that determination of the validity of any such patent rights, and the riskof infringement of such rights, are entirely their own responsibility.This standard is subject to revision at any time by the responsible technical committee and must be revie
17、wed every five years andif not revised, either reapproved or withdrawn. Your comments are invited either for revision of this standard or for additional standardsand should be addressed to ASTM International Headquarters. Your comments will receive careful consideration at a meeting of theresponsibl
18、e technical committee, which you may attend. If you feel that your comments have not received a fair hearing you shouldmake your views known to the ASTM Committee on Standards, at the address shown below.This standard is copyrighted by ASTM International, 100 Barr Harbor Drive, PO Box C700, West Con
19、shohocken, PA 19428-2959,United States. Individual reprints (single or multiple copies) of this standard may be obtained by contacting ASTM at the aboveaddress or at 610-832-9585 (phone), 610-832-9555 (fax), or serviceastm.org (e-mail); or through the ASTM website(www.astm.org). Permission rights to
20、 photocopy the standard may also be secured from the ASTM website (www.astm.org/COPYRIGHT/).TABLE 2 Mechanical Properties of Sheet and StripTemper Reduction in B&SNumbers (Reference)Percent Reduction(Reference)Ultimate Tensile Strength, psi (MPa) Minimum Elongation in2in.,%Typical MicrohardnessHK 10
21、0gmin maxA 0 0 50 000 (344) 80 000 (551) 30 12012 H 2 21 70 000 (482) 90 000 (620) 2 170Hard 4 37 80 000 (551) 100 000 (180) 1 180Spring 8 60 90 000 (620) 120 000 (827) . 200TABLE 3 Mechanical Properties of Wire, Rod, and TubingTemper Reduction in B&SNumbers (Reference)Percent Reduction(Reference)Ul
22、timate Tensile Strength, psi (MPa) Minimum Elongationin2in.,%Knoop Hardness(25 g, load)min maxA 0 0 40 000 (275) 60 000 (414) 25A9012018 H12 11 60 000 (414) 70 000 (482) 2 12014014 H 1 21 70 000 (482) 80 000 (551) 1 14016012 H 2 37 80 000 (551) 90 000 (620) 1 160200Hard 4 60 90 000 (620) 100 000 (689) 1 200240AWire 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 %.B731 96 (2012)2
