ASTM B476-21

This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the
Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
Designation:B476 −21
Standard Specification for
General Requirements for Wrought Precious Metal Electrical
1
Contact Materials
This standard is issued under the fixed designation B476; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision.Anumber 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 U.S. Department of Defense.
2
1. Scope 2.2 ASTM Standards:
B63Test Method for Resistivity of Metallically Conducting
1.1 This specification covers general requirements common
Resistance and Contact Materials
to wrought precious metal electrical contact alloy products in
E3Guide for Preparation of Metallographic Specimens
the form of sheet, strip, wire, and rod. Unless otherwise
E8Test Methods for Tension Testing of Metallic Materials
specifiedinthepurchaseorderorinanindividualspecification,
[Metric] E0008_E0008M
these general requirements shall apply to wrought electrical
E29Practice for Using Significant Digits in Test Data to
contact materials where indicated in the applicable product
Determine Conformance with Specifications
specifications issued by ASTM.
E55Practice for Sampling Wrought Nonferrous Metals and
1.2 In case of conflict, the requirements on the purchase
Alloys for Determination of Chemical Composition
order, the individual specification, and this general specifica-
E112Test Methods for Determining Average Grain Size
tion shall prevail in the sequence named.
E384Test Method for Microindentation Hardness of Mate-
1.3 The values stated in inch-pound units are to be regarded rials
as standard. The values given in parentheses are mathematical
3. Terminology
conversions to SI units that are provided for information only
and are not considered standard.
3.1 Definitions:
3.1.1 lot, n—the quantity of material of the same type, size,
1.4 This standard does not purport to address all of the
andfinishproducedatonetimefromthesamecastorheat,and
safety concerns, if any, associated with its use. It is the
heat treated in the same heat-treatment cycle.
responsibility of the user of this standard to become familiar
with all hazards including those identified in the appropriate
4. Ordering Information
Safety Data Sheet (SDS) for this product/material as provided
by the manufacturer, to establish appropriate safety, health,
4.1 Ordersformaterialtothisspecificationshallincludethe
and environmental practices, and determine the applicability
following information:
of regulatory limitations prior to use.
4.1.1 Designation and revision date of this specification.
1.5 This international standard was developed in accor-
4.1.1.1 Ifarevisiondateisnotdesignated,thelatestrevision
dance with internationally recognized principles on standard-
should be used.
ization established in the Decision on Principles for the
4.1.2 Designation and revision date of the applicable prod-
Development of International Standards, Guides and Recom-
uct specification.
mendations issued by the World Trade Organization Technical
4.1.2.1 Ifarevisiondateisnotdesignated,thelatestrevision
Barriers to Trade (TBT) Committee.
of the product specification should be used.
4.1.3 Description of material form,
2. Referenced Documents
4.1.4 Dimensions of the material,
2.1 The following documents of the issue in effect, on the
4.1.5 Total quantity of each size,
date of material purchase, form a part of this specification to 4.1.6 Temper of the material (annealed, cold worked, etc.),
the extent referenced herein:
4.1.7 Temper test (hardness or tensile) (Section 10),
4.1.8 Special requirements (if any), and
1
This specification is under the jurisdiction of ASTM Committee B02 on
Nonferrous Metals and Alloys and is the direct responsibility of Subcommittee
2
B02.05 on Precious Metals and Electrical Contact Materials. For referenced ASTM standards, visit the ASTM website, www.astm.org, or
Current edition approved Nov. 1, 2021. Published December 2021. Originally contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
approved in 1968. Last previous edition approved in 2017 as B476–01(2017). Standards volume information, refer to the standard’s Document Summary page on
DOI: 10.1520/B0476-21. the ASTM website.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
1

---------------------- Page: 1 ----------------------
B476−21
4.1.9 Certification (Section 14). 6.4.1 The thickness tolerances shall be those prescribed in
Table 3.
4.2 Specify the following, i
...