ASTM B684-97(2012)

Standard Specification for Platinum-Iridium Electrical Contact Materials

ABSTRACT
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.
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    
Element  
85 Pt/15 Ir  
90 Pt/10 Ir  
Weight %  
Weight %  
Pt  
balance  
balance  
Ir  
14.50-15.50  
9.50-10.50  
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  
Fe  
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.

General Information

• Status: Historical
• Publication Date: 31-Oct-2012
• ICS: 77.120.99 - Other non-ferrous metals and their alloys
• Technical Committee: B02 - Nonferrous Metals and Alloys
• Drafting Committee: B02.05 - Precious Metals and Electrical Contact Materials and Test Methods

Relations

• Replaces: ASTM B684-97(2008) - Standard Specification for Platinum-Iridium Electrical Contact Materials
• Effective Date: 01-Nov-2012

Standards Content (Sample)

NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Contact ASTM International (www.astm.org) for the latest information
Designation:B684 −97(Reapproved2012)
Standard Specification for
Platinum-Iridium Electrical Contact Materials
This standard is issued under the fixed designation B684; 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 (´) 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 3. Manufacture
3.1 Raw materials shall be of such quality and purity that
1.1 This specification covers an 85 % platinum—15 %
the finished product will have the properties and characteristics
iridium alloy, and a 90 % platinum—10 % iridium alloy, in the
prescribed in this specification.
form of rod, wire, strip, and sheet material for electrical
contacts.
3.2 The material shall be finished by such operations (cold
working, annealing, turning, grinding, or pickling) as are
1.2 The values stated in inch-pound units are to be regarded
required to produce the prescribed properties.
as standard. The values given in parentheses are mathematical
conversions to SI units that are provided for information only
4. General Requirements
and are not considered standard.
4.1 The provisions of Specification B476 shall apply to all
1.3 The original specification, B684 - 81, covered the 85 %
materials produced to this specification.
platinum 15 % iridium alloy. The 1997 revision of this speci-
fication added the 90 % platinum 10 % iridium alloy.
5. Chemical Requirements
1.4 This standard does not purport to address all of the
5.1 Material produced under the specification shall meet the
safety concerns, if any, associated with its use. It is the
requirements of chemical composition prescribed in Table 1.
responsibility of the user of this standard to become familiar
with all hazards including those identified in the appropriate
5.2 By agreement between purchaser and manufacturer,
Material Safety Data Sheet (MSDS) for this product/material
analysis may be required and limits established for elements or
as provided by the manufacturer, to establish appropriate
compounds not specified in the table of chemical composition.
safety and health practices, and determine the applicability of
NOTE 1—Analysis is regularly made for the elements for which specific
regulatory limitations prior to use.
limitsarelisted.If,however,thepresenceof“other”elementsissuspected
or indicated in the course of routine analysis, further analysis shall be
2. Referenced Documents
made to determine that the total of these “other” elements and the listed
2 impurities is not in excess of the total impurities limit.
2.1 ASTM Standards:
B277 Test Method for Hardness of Electrical Contact Mate-
6. Mechanical Requirements
rials
B476 Specification for General Requirements for Wrought 6.1 The contract or order may specify ultimate tensile
Precious Metal Electrical Contact Materials
strength, elongation, microhardness (Knoop or Vickers), hard-
E8 Test Methods for Tension Testing of Metallic Materials ness (Rockwell or Rockwell Superficial), or a combination of
E384 Test Method for Knoop and Vickers Hardness of
these mechanical properties as temper criterion. If the contract
Materials or order does not specify a temper criterion, then the criterion
for temper designation will be ultimate tensile strength.
6.2 The mechanical properties shall conform to those prop-
This specification is under the jurisdiction of ASTM Committee B02 on
erties listed in Table 2 and Table 3.The term “work hardened,”
Nonferrous Metals and Alloys and is the direct responsibility of Subcommittee
as used in these tables, refers to material which has been
B02.05 on Precious Metals and Electrical Contact Materials.
subjected to a minimum of 30 % reduction in cross–sectional
Current edition approved Nov. 1, 2012. Published November 2012. Originally
approved in 1981. Last previous edition approved in 2008 as B684 – 97 (2008). area.
DOI: 10.1520/B0684-97R12.
6.3 All test specimens shall be full size when practical.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
6.4 All tests are to be conducted at room temperature, 65 to
Standards volume information, refer to the standard’
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