1、Designation: B 540 97 (Reapproved 2008)Standard Specification forPalladium Electrical Contact Alloy1This standard is issued under the fixed designation B 540; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revisio
2、n. 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 an alloy containing pal
3、ladium,silver, copper, gold, platinum, and zinc in the form of wire, rod,and strip 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 no
4、t considered standard.1.3 The following safety hazard caveat pertains only to thetest methods portion, Section 6 of this specification. Thisstandard does not purport to address all of the safety concerns,if any, associated with its use. It is the responsibility of the userof this standard to establi
5、sh appropriate safety and healthpractices and determine the applicability of regulatory limita-tions prior to use.1.4 It is the responsibility of the user to become familiarwith all hazards including those identified in the appropriateMaterial Safety Data Sheet (MSDS) for this product/materialas pro
6、vided by the manufacturer.2. Referenced Documents2.1 ASTM Standards:2B 476 Specification for General Requirements for WroughtPrecious Metal Electrical Contact MaterialsE8 Test Methods for Tension Testing of Metallic MaterialsE 384 Test Method for Microindentation Hardness of Ma-terials3. Materials a
7、nd Manufacture3.1 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, pickling)as are r
8、equired to produce the prescribed properties.4. Chemical Composition4.1 Material produced under the specification shall meet therequirements of chemical composition shown in Table 1.5. Mechanical Properties5.1 The contract or order may specify ultimate tensilestrength, elongation, mirohardness (Knoo
9、p or Vickers), or acombination of these mechanical properties (as listed in Table2, Table 3, and Table 4) as temper criterion. If the contract ororder does not specify a temper criterion, then the criterion fortemper designation will be ultimate tensile strength and elon-gation.6. Test Methods6.1 Te
10、st methods shall be in accordance with SpecificationB 476.6.1.1 Knoop hardness tests shall be in accordance with TestMethod E 384. Material 0.005 in. (0.13 mm) in thickness(diameter) and larger shall be tested using a 100-g indenterload. Material less than 0.005 in. (0.13 mm) in thickness(diameter)
11、shall be tested using a 50-g indenter load. Aminimum of five hardness indentations shall be made on eachspecimen. All indentations shall be made so that the long axisof the indenter is parallel to the rolling or drawing direction of1This specification is under the jurisdiction of ASTM Committee B02
12、onNonferrous Metals and Alloys and is the direct responsibility of SubcommitteeB02.05 on Precious Metals and Electrical Contact Materials.Current edition approved May 1, 2008. Published June 2008. Originallyapproved in 1970. Last previous edition approved in 2002 as B 540 97 (2002).2For referenced A
13、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 RequirementsElementComposition,weight %Palladium 34.036.0Silv
14、er 29.031.0Copper 13.514.5Gold 9.510.5Platinum 9.510.5Zinc 0.81.2Total platinum group metal impurities(iridium, osmium, rhodium, ruthenium)0.1 maxTotal base metal impurities 0.2 max1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.the
15、material. The hardness value reported shall be the averageof the five indentations.6.1.2 All tension test specimens shall be full cross-sectionsize when practical (see Test Methods E8).6.1.3 All tests shall be conducted in room temperature, 65 to85F (18.3 to 29.4C).6.2 Chemical analysis shall be per
16、formed by spectrochemi-cal or wet analysis methods.7. Inspection and Testing7.1 Material furnished under this specification shall beinspected and tested by the manufacturer as listed below:7.1.1 Visual inspection at 103 magnification,7.1.2 Tension or hardness tests, or both, for temper verifi-cation
17、,7.1.3 Dimensional inspection, and7.1.4 Chemical analysis when indicated by the purchaseorder.8. Keywords8.1 contact; electrical contact material; palladium alloy;precious metalTABLE 2 Mechanical Properties of WireA(0.004 to 0.020 in. (0.1 to 0.5 mm) diameter)PropertyTemperSolution-AnnealedStress-Re
18、lievedDuctileHeat-TreatedAge-HardenedHeat TreatedAge-HardenedTensile strength, ksi 110130 140170 160190 160200Tensile strength, MPa 760900 9701170 11001310 11001380Elongation, % in 2 in. (51 mm) 20 min 1020 818 110Hardness, KnoopB200260 280340 320370 350410Hardness, Vickers, 100-g load (50-g 190250
19、265340 320380 330400under 0.005-diameter)AThe limits to all properties apply only to the sizes specified.BSee 7.1.1.TABLE 3 Mechanical Properties of WireA(Over 0.020 to 0.040 in. (0.5 to 1.0 mm) diameter)PropertyTemperSolution-Annealed Stress-Relieved Ductile-Hardened Age-HardenedTensile strength, k
20、si 105130 130170 155180 160200Tensile strength, MPa 720860 9001170 10701240 11001380Elongation, % in 2 in. (51 mm) 15 min 825 825 110Hardness, KnoopB200260 280340 310360 340400Hardness, Vickers: 190250 265340 320380 330400100-g loadAThe limits to all properties apply only to the sizes specified.BSee
21、 7.1.1.TABLE 4 Mechanical Properties of StripA(0.003 to 0.020 in. (0.075 to 0.5 mm) thick)PropertyTemperSolution-Annealed Stress-Relieved Ductile-Hardened Age-HardenedTensile strength, ksi 110135 135160 150185 160200Tensile strength, MPa 760930 9301100 10301280 11001380Elongation, % in 2 in. (51 mm)
22、 12 min 825 825 110Hardness, KnoopB200260 280340 300360 340400Hardness, Vickers 100-g load (50-g load under0.005 thick)185255 265340 320380 330400AThe limits to all properties apply only to the sizes specified.BSee 7.1.1.B 540 97 (2008)2APPENDIX(Nonmandatory Information)X1. REFERENCE PROPERTIES OF P
23、ALLADIUM ALLOY ELECTRICAL CONTACT MATERIALX1.1 Table X1.1 provides a list of typical property valueswhich are useful for engineering calculations in electricalcontact design and application.ASTM International takes no position respecting the validity of any patent rights asserted in connection with
24、any item mentionedin this standard. 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 technic
25、al committee and must be reviewed 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
26、 at a meeting of theresponsible 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 Harbo
27、r Drive, PO Box C700, West Conshohocken, 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.a
28、stm.org).TABLE X1.1 Typical Physical PropertiesSolution-AnnealedStress-RelievedDuctile-HardenedAge-HardenedResistivity, V cm 34.9 33.2 31.6 31.6Density, Mg/m311.8 11.8 11.8 11.8Solidus temperature, C 1015 1015 1015 1015Linear coefficient of thermal expansion/C (23-100C) 13.5 3 10613.5 3 10613.5 3 10
29、613.5 3 106Thermal emf versus platinum (0-100C), V/C 10 9 8 8Softening voltage, mV 220 220 220 220Melting voltage, mV 385 . 400 400Fatigue strength (rotating-bending)at 108cycles:ksi 50 50 50 50MPa 345 345 345 345Modulus of elasticity in tension:ksi 17 3 10317 3 10317 3 10317 3 103MPa 117 3 103117 3 103117 3 103117 3 103Proportional limit:ksi 90 135 135 145MPa 620 930 930 1000B 540 97 (2008)3
