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ASTM B693-91(2006)

(Specification)

Standard Specification for Silver-Nickel Electrical Contact Materials

Standard Specification for Silver-Nickel Electrical Contact Materials

ABSTRACT
This specification covers electrical contact components made from silver-nickel by powder metallurgical procedures. This covers compositions within the silver-nickel system normally specified by users of electrical contacts. Chemical analysis shall be performed to evaluate material conformance to specified composition requirements. A representative sample of chips may be obtained by milling, drilling, or crushing with dry tools, (without lubrication). In order to obtain free chips, the parts selected for testing shall have the oil extracted, if necessary. Physical tests including microstructure shall be performed on a representative number of specimens.
SCOPE
1.1 This specification covers electrical contact components made from silver nickel by powder metallurgical procedures.
1.2 This specification covers compositions within the silver-nickel system normally specified by users of electrical contacts.
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-May-2006
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
Current Stage
Ref Project

Relations

Replaces
ASTM B693-91(2001) - Standard Specification for Silver-Nickel Electrical Contact Materials
Effective Date
01-Jun-2006
Replaced By
ASTM B693-91(2012) - Standard Specification for Silver-Nickel Electrical Contact Materials
Effective Date
01-May-2012

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ASTM B693-91(2006) - Standard Specification for Silver-Nickel Electrical Contact Materials
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NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.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: B693 – 91 (Reapproved 2006)
Standard Specification for
Silver-Nickel Electrical Contact Materials
This standard is issued under the fixed designation B693; 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.
1. Scope 3.1.3 Physical properties (see Section 5 and reference table
in Appendix X1).
1.1 This specification covers electrical contact components
3.1.4 Certification (see Section 13).
made from silver nickel by powder metallurgical procedures.
3.1.5 Other features as agreed upon between the seller and
1.2 This specification covers compositions within the silver-
the user.
nickel system normally specified by users of electrical con-
tacts.
4. Chemical Composition
1.3 This standard does not purport to address all of the
4.1 The material shall conform to composition limits as
safety concerns, if any, associated with its use. It is the
agreed upon between the manufacturer and user.
responsibility of the user of this standard to become familiar
4.2 The chemical analysis shall be made in accordance with
with all hazards including those identified in the appropriate
the methods described in the newest edition of Annual Book of
Material Safety Data Sheet (MSDS) for this product/material
ASTM Standards, Vol 03.05 and 03.06, or by any other
as provided by the manufacturer, to establish appropriate
approved method agreed upon between manufacturer and
safety and health practices, and determine the applicability of
purchaser.
regulatory limitations prior to use.
5. Physical Requirements
2. Referenced Documents
5.1 The manufacturer and purchaser shall agree on qualifi-
2.1 ASTM Standards:
cation tests for determination of physical properties.
B328 Test Method for Density, Oil Content, and Intercon-
5.2 The tests shall be performed on production parts,
nected Porosity of Sintered Metal Structural Parts and
3 wherever practical, or applicable. (Small size contacts do not
Oil-Impregnated Bearings
lend themselves to accurate conductivity measurement.)
E18 Test Methods for Rockwell Hardness of Metallic Ma-
5.3 The tests shall be determined after consideration of the
terials
function of the part.
E384 Test Method for Microindentation Hardness of Mate-
5.4 The typical properties of the most common types of
rials
silver-nickel electrical contact materials are given in the
3. Ordering Information appendix.
3.1 Orders for this material under this specification shall
6. Dimensions, Mass, and Permissible Variations
include the following information.
6.1 Permissible variations in dimensions shall be within the
3.1.1 Dimensions (see Section 6).
limits specified on drawings describing the contacts and
3.1.2 Chemical composition (see reference table in Appen-
accompanying the order, or shall be within the limits specified
dix X1).
in the purchase order.
This specification is under the jurisdiction of ASTM Committee B02 on
7. Workmanship, Finish, and Appearance
Nonferrous Metals and Alloys and is the direct responsibility of Subcommittee
7.1 The parts shall be free of defects in material or process-
B02.05 on Precious Metals and Electrical Contact Materials.
Current edition approved June 1, 2006. Published June 2006. Originally
ing, which would seriously affect their performance.
approved in 1981. Last previous edition approved in 2001 as B693 – 91 (2001).
DOI: 10.1520/B0693-91R06.
8. Sampling
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
8.1 Lot—Unless otherwise specified, a lot shall consist of
contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
Standards volume information, refer to the standard’s Document Summary page on
parts of the same form, and dimensions, made of powders of
the ASTM website.
the same particle size range and composition, processed under
Withdrawn. The last approved version of this historical standard is referenced
the same conditions, and submitted for inspection at one time.
on www.astm.org.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
B693 – 91 (2006)
9. Number of Tests and Retests reasonable assurance that future lots will be similar in proper-
ties and microstructure to the initial test or sample contact
9.1 Chemical Analysis—The manufacturer and purchaser
supplied.
shall agree on a representative number of specimens for
chemical analysis. A representative sample of chips may be
11. Inspection
obtained by milling, drilling, or crushing with dry tools,
11.1 Inspection of the material shall be agreed upon be-
(without lubrication). In order to obtain free chips, the parts
tween the purchaser and the supplier as part of the purchase
selected for test shall have the oil extracted in accordance with
contract.
Test Method B328, if necessary.
9.2 Physical Tests—The manufacturer and purchaser sha
...

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This specification covers electrical contact components made from silver-nickel by powder metallurgical procedures. This covers compositions within the silver-nickel system normally specified by users of electrical contacts. Chemical analysis shall be performed to evaluate material conformance to specified composition requirements. A representative sample of chips may be obtained by milling, drilling, or crushing with dry tools, (without lubrication). In order to obtain free chips, the parts selected for testing shall have the oil extracted, if necessary. Physical tests including microstructure shall be performed on a representative number of specimens.
SIGNIFICANCE AND USE
9.1 Proprietary methods for manufacture of these materials vary significantly among suppliers and these methods influence such properties as arc erosion, contact resistance, and the tendency to weld in service. Since the performance of contacts in a device depends on numerous factors outside the contact itself (opening speed, closing speed, contact pressure, contact bounce, environmental variations, assembly technique and variations, etc.), this specification cannot ensure performance control in the application. As part of the qualification on initial samples, it is recommended that the user functionally test the materials electrically for all devices applicable to the material's use. This specification provides a means for the contact manufacturer and contact user to reach agreement on the details of material to be supplied for a specific use and reasonable assurance that future lots will be similar in properties and microstructure to the initial test or sample contact supplied.
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