You are being redirected because this document is part of your ASTM Compass® subscription.
    This document is part of your ASTM Compass® subscription.

    ASTM B684 - 97(2012)

    Standard Specification for Platinum-Iridium Electrical Contact Materials

    Active Standard ASTM B684 | Developed by Subcommittee: B02.05

    Book of Standards Volume: 02.04

      Format Pages Price  
    PDF 3 $39.00   ADD TO CART
    Hardcopy (shipping and handling) 3 $39.00   ADD TO CART


    This specification covers two platinum-iridium alloys in the form of rod, wire, strip, and sheet material for electrical contacts. Raw materials shall be of such quality and purity that the finished product (produced by cold working, annealing, turning, grinding, or pickling as required) will have the properties and characteristics prescribed in this specification. The alloys shall meet the requirements of chemical composition specified for platinum, iridium, total impurities, total platinum group (palladium, rhodium, osmium, ruthenium, and gold), total other impurities (including lead, antimony, bismuth, tin, arsenic, cadmium, zinc, and iron) and other elements. Ultimate tensile strength, elongation, microhardness (Knoop or Vickers), hardness (Rockwell or Rockwell Superficial), or a combination of these mechanical properties may be specified as criterion for temper designation. Annealed and work hardened wire and strip shall conform to the mechanical requirements prescribed for ultimate tensile strength, elongation, and microhardness. Knoop hardness test, tension test, and chemical analysis using spectrochemical or wet analysis method shall be performed.

    This abstract is a brief summary of the referenced standard. It is informational only and not an official part of the standard; the full text of the standard itself must be referred to for its use and application. ASTM does not give any warranty express or implied or make any representation that the contents of this abstract are accurate, complete or up to date.

    1. Scope

    1.1 This specification covers an 85 % platinum—15 % iridium alloy, and a 90 % platinum—10 % iridium alloy, in the form of rod, wire, strip, and sheet material for electrical contacts.

    TABLE 1 Chemical Requirements


    85 Pt/15 Ir

    90 Pt/10 Ir


    Weight %

    Weight %







    Total Impurities

    0.2 max.

    0.2 max.

    Total Platinum Group (Pd, Rh, Os, Ru), Au

    0.1 max.

    0.1 max.

    Total Other Impurities (including the
     elements below)

    0.1 max.

    0.1 max.

    Pb, Sb, Bi, Sn, As, Cd, Zn

    0.01 max each

    0.01 max each


    0.015 max each

    0.015 max each

    Other elements

    0.02 max each

    0.02 max each

    1.2 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard.

    1.3 The original specification, B684 - 81, covered the 85 % platinum 15 % iridium alloy. The 1997 revision of this specification added the 90 % platinum 10 % iridium alloy.

    1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to become familiar with all hazards including those identified in the appropriate Material Safety Data Sheet (MSDS) for this product/material as provided by the manufacturer, to establish appropriate safety and health practices, and determine the applicability of regulatory limitations prior to use.

    2. Referenced Documents (purchase separately) The documents listed below are referenced within the subject standard but are not provided as part of the standard.

    ASTM Standards

    B277 Test Method for Hardness of Electrical Contact Materials

    B476 Specification for General Requirements for Wrought Precious Metal Electrical Contact Materials

    E8 Test Methods for Tension Testing of Metallic Materials

    E384 Test Method for Knoop and Vickers Hardness of Materials

    ICS Code

    ICS Number Code 77.120.99 (Other non-ferrous metals and their alloys)

    UNSPSC Code

    UNSPSC Code

    Referencing This Standard
    Link Here
    Link to Active (This link will always route to the current Active version of the standard.)

    DOI: 10.1520/B0684-97R12

    ASTM International is a member of CrossRef.

    Citation Format

    ASTM B684-97(2012), Standard Specification for Platinum-Iridium Electrical Contact Materials, ASTM International, West Conshohocken, PA, 2012,

    Back to Top