ASTM B702 - 93 (2024) 铜钨电接触材料的标准规范

VIP免费

史蒂文 2025-04-28 117 197.1KB 3 页 18星币

Designation: B702 −93 (Reapproved 2024)
Standard Speciﬁcation for
Copper-Tungsten Electrical Contact Material
1
This standard is issued under the ﬁxed designation B702; 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
1.1 This speciﬁcation covers electrical contact components
made from copper tungsten by powder metallurgical proce-
dures.
1.2 This speciﬁcation covers compositions within the cop-
per tungsten system normally speciﬁed by users of contacts.
1.3 The values stated in inch-pound units are to be regarded
as standard. No other units of measurement are included in this
standard.
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
Data Safety Sheet (SDS) for this product/material as provided
by the manufacturer, to establish appropriate safety, health,
and environmental practices, and determine the applicability
of regulatory limitations prior to use.
1.5 This international standard was developed in accor-
dance with internationally recognized principles on standard-
ization established in the Decision on Principles for the
Development of International Standards, Guides and Recom-
mendations issued by the World Trade Organization Technical
Barriers to Trade (TBT) Committee.
2. Referenced Documents
2.1 ASTM Standards:
2
B328 Test Method for Density, Oil Content, and Intercon-
nected Porosity of Sintered Metal Structural Parts and
Oil-Impregnated Bearings (Withdrawn 2009)
3
3. Signiﬁcance and Use
3.1 Proprietary methods for manufacture of these materials
vary signiﬁcantly among suppliers and these methods inﬂuence
such properties as arc erosion, contact resistance, and 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 electri-
cally test the materials for all devices applicable to the
material’s use. This speciﬁcation will provide a means for the
contact manufacturer and contact user to reach agreement on
the details of material to be supplied for a speciﬁed use and
reasonable assurance that future lots will be similar in proper-
ties and microstructure to the initial test or sample contacts
supplied.
4. Ordering Information
4.1 Orders for this material under this speciﬁcation shall
include the following information:
4.1.1 Dimensions (see Section 8),
4.1.2 Chemical composition (see reference tables in Related
Material as possible guideline),
4.1.3 Physical properties (see Section 6and reference tables
as guideline),
4.1.4 Certiﬁcation (see Section 11), and
4.1.5 Other features as agreed upon between the vendor and
the user.
5. Chemical Requirements
5.1 The material shall conform to composition limits as
agreed upon between the manufacturer and the user.
5.2 The chemical analysis shall be made in accordance with
the methods prescribed in the newest edition of Annual Book of
ASTM Standards, or by any other approved method agreed
upon between the manufacturer and the purchaser.
6. Other Properties
6.1 The manufacturer and the purchaser shall agree on
qualiﬁcation tests for determination of physical properties.
6.2 The tests shall be performed on production parts,
wherever practical or applicable. (Small size contacts do not
lend themselves to accurate conductivity measurement.)
1
This speciﬁcation is under the jurisdiction of ASTM Committee B02 on
Nonferrous Metals and Alloys and is the direct responsibility of Subcommittee
B02.05 on Precious Metals and Electrical Contact Materials and Test Methods.
Current edition approved Nov. 1, 2024. Published November 2024. Originally
approved in 1982. Last previous edition approved in 2019 as B702 – 93 (2019).
DOI: 10.1520/B0702-93R24.
2
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
contact ASTM Customer Service at www.astm.org/contact. For Annual Book of
ASTM Standards volume information, refer to the standard’s Document Summary
page on the ASTM website.
3
The last approved version of this historical standard is referenced on
www.astm.org.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
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.
1

6.3 The tests shall be determined after consideration of the

function of the part.

6.4 The typical properties of ﬁve most common types of

copper-tungsten contacts are given in Appendix X1.

7. Dimensions and Permissible Variations

7.1 Permissible variations in dimensions shall be within the

limits speciﬁed on drawings describing the contacts and

accompanying the order, or shall be within the limits speciﬁed

in the purchase order.

8. Workmanship, Finish, and Appearance

8.1 The parts shall be free of defects in material or

processing, which would seriously affect their performance.

9. Sampling and Inspection

9.1 Lot—Unless otherwise speciﬁed, a lot shall consist of

parts of the same form, and dimensions, made of powders of

the same particle size range and composition, processed under

the same conditions, and submitted for inspection at one time.

9.2 Chemical Analysis—At least one sample for chemical

analysis shall be taken from each lot. A representative sample

of chips may be obtained by milling, drilling, or crushing at

least two pieces with dry tools, without lubrication. In order to

obtain oil-free chips, the parts selected for test shall have the

oil extracted in accordance with Test Method B328, if neces-

sary.

9.2.1 These speciﬁcation limits do not preclude the possible

presence of other unnamed elements, impurities or additives.

Analysis shall be regularly made only for the minor elements

listed in the table. However, if a user knows of elements that

might be detrimental to their application or has other reasons

for requiring analysis for speciﬁc elements, then agreement

between manufacturer and purchaser for both limits and

methods of analysis should be required for elements not

speciﬁed.

9.3 Physical Tests—The manufacturer and the purchaser

shall agree on a representative number of specimens for

physical tests including microstructure.

10. Rejection and Rehearing

10.1 Unless otherwise speciﬁed, rejections based on tests

made in accordance with the speciﬁcation shall be reported to

the manufacturer within 30 days of the receipt of shipment.

11. Certiﬁcation

11.1 A certiﬁcation, when requested by the user, based on

the manufacturer’s quality control, that the material conforms

to the requirements of this speciﬁcation shall be furnished upon

request of the purchaser, provided the request is made at the

time of cost quotation and at the time of order placement.

12. Keywords

12.1 contacts; copper; copper–tungsten; powder metallurgy;

tungsten; tungsten–copper

APPENDIX

(Nonmandatory Information)

X1. TYPICAL PROPERTY VALUES

X1.1 Scope

X1.1.1 The following information provides guidelines for

users and manufacturers of copper-tungsten contact material.

Typical ranges of chemistry and properties are given for the

range of compositions available. Some manufacturers offer

speciﬁc compositions other than those listed. Properties are

inﬂuenced by the particle size, shape, and distribution of the

tungsten as well as by the presence of additives or other

manufacturing process variables. The best choice for a given

application should be mutually decided between the purchaser

and the supplier using their mutual experience and application

engineering knowledge.

X1.1.2 With the knowledge that several types of material

are available, care should be taken to ensure that production

lots are the same in all respects as samples and that if a vendor

change is made, noticeable property or performance variables

are possible. See Table X1.1.

B702 − 93 (2024)

ASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentioned

in this standard. Users of this standard are expressly advised that determination of the validity of any such patent rights, and the risk

of infringement of such rights, are entirely their own responsibility.

This standard is subject to revision at any time by the responsible technical committee and must be reviewed every ﬁve years and

if not revised, either reapproved or withdrawn. Your comments are invited either for revision of this standard or for additional standards

and should be addressed to ASTM International Headquarters. Your comments will receive careful consideration at a meeting of the

responsible technical committee, which you may attend. If you feel that your comments have not received a fair hearing you should

make your views known to the ASTM Committee on Standards, at the address shown below.

This standard is copyrighted by ASTM International, 100 Barr Harbor 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 above

address or at 610-832-9585 (phone), or through the ASTM website (www.astm.org/contact). Permission rights to photocopy the

standard may also be secured from the Copyright Clearance Center, 222 Rosewood Drive, Danvers, MA 01923, Tel: (978) 646-2600;

http://www.copyright.com/

TABLE X1.1 Chemical Requirements

Class A Class B Class C Class D Class E

Copper, % 48–52 38–42 28–32 23–27 18–22

Tungsten, % balance balance balance balance balance

Additives (Individual or total), max,% 1.00 1.00 1.00 1.00 1.00

Physical Properties

Class A Class B Class C Class D Class E

Hardness, Rockwell B 69–83 77–90 85–98 89–102 94–106

Density, Mg/m

at 96 % theoretical 11.7 12.7 13.7 14.3 15.0

Electrical conductivity,

% IACS 56–64 49–57 44–52 41–48 38–45

Electrical conductivity,

% IACS 38–56 34–49 29–43 27–41 25–37

Note—Hardness and density values cover both types.

Physical Properties

Class A Class B Class C Class D Class E

Tensile Strength, ksi MPa 50–60

344–413

55–65

379–448

75–85

516–585

85–95

585–654

90–100

620–689

Modulus of Rupture, ksi MPa 75–85

517–586

110–120

758–827

130–140

896–965

140–150

965–1034

150–160

1034–1103

Coefficient of Expansion, in./in.·

°F m/m·K

7.2 × 10

−6

13 × 10

−6

6.6 × 10

−6

11.9 × 10

−6

5.7 × 10

−6

10.3 × 10

−6

5.3 × 10

−6

9.5 × 10

−6

4.9 × 10

−6

8.8 × 10

−6

Analysis is regularly made for the elements for which speciﬁc limits are listed. If, however, the presence of “other” elements is suspected or indicated in the course of

routine analysis, further analysis shall be made to determine that the total of these “other” elements and the listed impurities are not in excess of the total impurities limit.

These data do not constitute a part of the speciﬁcations. They indicate to the purchaser the properties that may be expected from a given particle size of powder. The

values will vary to some degree with the size of part, conﬁguration of part, composition, and microstructure. Certain speciﬁc applications may require modiﬁcation of these

basic materials. In such case, the properties required are determined by agreement between the purchaser and the supplier.

Typical values for inﬁltrated type.

Typical values for liquid phase sintered type.

Items that are normally useful for engineering calculations in contact design but are not speciﬁed.

B702 − 93 (2024)

文档加载中……请稍候！
如果长时间未打开，您也可以点击刷新试试。

下载文档到电脑，查找使用更方便

亲，本站95%以上的标准规范都面向会员免费，办理VIP会员下载更省钱，平均每篇不到2元

立即下载 VIP免费下载

已全部加载

标签： #电接触 #电接触材料 #标准规范

摘要：

本页面提供ASTM B702 - 93 (2024) 铜钨电接触材料标准规范的核心内容解读。该标准由美国材料与试验协会发布，最新修订于2024年，主要规范了用于电接触应用的铜钨复合材料的技术要求、化学成分、物理性能及测试方法。铜钨材料因其优异的耐电弧侵蚀性、高导电导热性以及良好的机械强度，广泛应用于高压开关、断路器、继电器及电焊电极等领域。本文档详细介绍了标准中的材料分类、密度、硬度、电阻率等关键指标，以及检测与验收规则，适用于电气制造、有色金属材料研发及质量检测人员参考，帮助用户准确理解并应用

展开>> 收起<<

ASTM B702 - 93 (2024) 铜钨电接触材料的标准规范.pdf

共3页,预览3页

还剩页未读，继续阅读

声明：本文档系会员上传，若文档所含内容侵犯了您的版权或隐私，请立即通知，我们立即给予侵权申诉删除！

ASTM B702 - 93 (2024) 铜钨电接触材料的标准规范

相关推荐

开通VIP享超值会员特权

相关内容

热门标签

举报选择: