JB/T 7098-2002 Technical requirements for copper-chromium electrical contacts
Some standard content:
ICS 29.120.99
Machinery Industry Standard of the People's Republic of China
JB/T 7098—2002
Replaces JB/T7098—1993
Technical specification for copper-chromium electrical contact2002-12-27 Issued
Implementation on 2003-04-01
Issued by the State Economic and Trade Commission of the People's Republic of China
Normative reference documents
3 Representative symbols and marking methods,
4 Requirements
5 Sampling
6 Test methods
7 Marking, labeling and packaging
Appendix A (Normative Appendix) Metallographic structure legend Appendix B (Normative Appendix) Product Inspection Sampling Table.. Figure Al
Sintering method CuCr (25)
Figure A.2 Sintering method CuCr (50)
Figure A.3 Melt immersion method CuCr (25)
(100×)
(100×)
Figure A.4 Melt immersion method CuCr (50) (100×) Figure A.5 Arc melting method CuCr (25) (100×) Figure A.6 Vacuum casting method CuCr (25) (100×)
Table 1 Representative symbols, chemical symbols, chemical composition and physical and mechanical properties of copper-chromium electrical contacts. Table B.1 Sampling table
JB/T 7098—2002
This standard replaces JB/T7098-1993 "Technical Conditions for Copper-Chromium Contact Materials". The main changes of this standard compared with JB/T7098-1993 are as follows: 7098—2002
The standard structure is rearranged in accordance with the requirements of GB/T1.1-2000 "Guidelines for Standardization Part 1: Structure and Writing Rules of Standards":
- Added symbols to distinguish production processes (see Chapter 3);- Added copper-chromium (25) electrical contacts (see Chapter 4);- In order to align with international practice, the unit of hardness value is changed to kgf/mm2 without unit (see Table 1 in 4.1); The requirements for the enriched phase on the surface of electrical contacts are improved (4.2 of the 1993 edition, 4.3 of this edition); The metallographic structure legend adds copper-chromium electrical contacts produced by arc melting and vacuum casting (4.4 of the 1993 edition, Appendix A of this edition);
Make appropriate adjustments to sampling (Chapter 6 of the 1993 edition; Chapter 5 of this edition); Appendix A and Appendix B of this standard are normative appendices. This standard is proposed by the China Machinery Industry Federation. This standard is under the jurisdiction of the National Technical Committee for Standardization of Electrical Alloys. This standard was drafted by Guilin Electrical Science Research Institute, and Xi'an High Voltage Electrical Equipment Research Institute, Zhejiang Metallurgical Research Institute, China Zhenhua (Group) Technology Co., Ltd. Yuguang Branch, Xi'an Jietian Electric Co., Ltd., Chengdu Xuguang Electronics Co., Ltd., Shaanxi Baoguang Vacuum Electric Co., Ltd., Zhengzhou Light Metal Research Institute, Shaanxi Sirui Industrial Co., Ltd. and other companies participated in the drafting. The main drafters of this standard are: Xie Zhongguang, Wang Wenjing, Fang Ningxiang, Yuan Fuxing, Ye Fan, Wu Minghui, Li Gang, Chen Junping, Han Yong, and Wei Congren.
This standard was first issued in 1993, and this is the first revision. III
1 Scope
Technical conditions for copper-chromium electrical contacts
This standard specifies the requirements, sampling, test methods, marking, labeling and packaging of copper-chromium electrical contacts. This standard applies to copper-chromium electrical contact products for vacuum interrupters. 2 Normative references
JB/T 7098--2002
The clauses in the following documents become the clauses of this standard through reference in this standard. For all dated references, all subsequent amendments (excluding errata) or revisions are not applicable to this standard. However, parties reaching an agreement based on this standard are encouraged to study whether the latest versions of these documents can be used. For all undated references, the latest versions are applicable to this standard. GB/T2828 Batch inspection counting sampling procedures and sampling tables (applicable to continuous batch inspection) GB/T5587 Basic shape, size, symbol and marking of silver-based electrical contacts JB/T5351 Basic performance test method of vacuum switch contact materials JB/T8443.1~2 Chemical analysis method of copper-chromium contact materials JB/T8985 Metallographic inspection method of electrical contact materials 3 Representative symbols and marking methods
3.1 The representative symbols of copper-chromium electrical contacts shall comply with the requirements of relevant provisions of GB/T5587. 3.2 The marking method of copper-chromium electrical contact products is as follows: Cu
(××)
Note: F——Powder metallurgy, including sintering method, melt infiltration method, etc.: (F or T)
Production process representative symbol
Chromium weight percentage content
Chromium (element symbol)
Copper (element symbol)
T——Special smelting method, including arc melting method, vacuum casting method, etc. 4 Requirements
The representative symbol, chemical symbol, chemical composition and physical and mechanical properties of copper-chromium electrical contacts shall comply with the requirements of Table 1. Table 1 Representative symbols, chemical symbols, chemical composition and physical and mechanical properties of copper-chromium electrical contacts Product
(25）
Cu--Cr
(50）
Chemical composition (mass fraction, %)
Gas content
Oxygen content
≤0.0500
≤0.0500
Nitrogen content
≤0.0030
≤0.0040wwW.bzxz.Net
Physical and mechanical properties
70～100
80～110
Electrical conductivity
JB/T 7098--2002
4.2 Surface roughness of copper-chromium electrical contacts Ra≤6.3μm. 4.3 The rough surface and machined surface of the copper-chromium electric contact shall not have cracks, pieces falling off, pores and inclusions with a length greater than 150μm, scratches and chromium-enriched phase or copper-enriched phase greater than or equal to 1mm2. Three enriched phases greater than or equal to 0.5mm2 and less than 1mm are allowed, and the distance between the enriched phases shall not be less than 15mm. 4.4 The metallographic structure of the copper-chromium electric contact shall be evenly distributed. For the metallographic structure diagram, see Appendix A. 4.5 There shall be no pores or inclusions with a length greater than or equal to 150um on the entire grinding surface of the metallographic specimen; when the length of the pores or inclusions is greater than or equal to 80μm and less than 150μm, there shall be no more than three pores within a 1cm grinding surface. 5 Sampling
5.1 The product quality of copper-chromium electric contacts shall be inspected in batches by the inspection department of the production unit. Products continuously produced under the same batch of raw materials and the same process shall be considered as a batch.
5.2 The appearance quality of copper-chromium electric contacts shall be inspected 100% per batch. 5.3 The chemical composition, density, hardness and conductivity of copper-chromium electric contacts shall be inspected according to GB/T2828 with a normal inspection and secondary sampling plan and a special inspection level of S-2 (see Appendix B), and the qualified quality level is 10. 5.4 The gas content and metallographic structure of copper-chromium electric contacts shall be inspected according to GB/T2828 with a normal inspection and secondary sampling plan and a special inspection level of S-1 (see Appendix B), and the qualified quality level is 10. 5.5 If the appearance quality of copper-chromium electric contacts does not meet the requirements of 4.2 and 4.3, the items shall be judged as unqualified. 6 Test method
6.1 The appearance quality shall be inspected with the naked eye or a magnifying glass (≤10 times). 6.2 Chemical composition analysis shall be carried out in accordance with the provisions of JB/T8443.1~2. 6.3 The inspection of gas content, density, hardness and conductivity shall be carried out in accordance with the provisions of JB/5351. 6.4 The metallographic structure shall be inspected at 100 times in accordance with the provisions of JB/T8985; the area of the entire grinding plane of the metallographic specimen must be greater than or equal to 1/2 of the longitudinal section area along the diameter of the product.
7 Marking, labeling and packaging
The marking of copper-chromium electrical contacts shall be carried out in accordance with the provisions of Chapter 3. 7.2 Each batch of products shall be accompanied by a product certificate. 7.3 The product certificate shall indicate:
Electric contact product name (or representative symbol), size specification and batch number, and this standard number; a) [
Chemical composition, physical and mechanical properties;
Date of manufacture;
Name of manufacturer;
e) Seal of the inspector and seal of the inspection department. 7.4 Copper-chromium electrical contacts must be sealed and packed. Each pair (piece) of electrical contacts must be packed in a plastic bag and sealed. They must be packed into a packing box. The box must be equipped with measures to prevent electrical contacts from being abraded and moisture-proof. Each box should not exceed 30kg. 7.5 The outside of the packaging box should be marked with:
a) manufacturer's name;
b) electric contact product name or representative symbol; c) gross weight and net weight;
d) moisture-proof, handle with care, and shock-proof signs.
7.6 Copper-chromium electric contacts should avoid severe vibration during transportation to avoid mechanical damage. 7.7 Copper-chromium electric contacts should be stored in a dry, ventilated warehouse without corrosive media to prevent moisture. 2
Appendix A
(Normative Appendix)
Metallurgical Structure Legend
A.1 This metallographic structure legend can be used as a reference when checking the metallographic structure of copper-chromium electric contacts. A.2 The metallographic structure legend of copper-chromium electric contacts produced by sintering method is shown in Figures A.1 and A.2. Figure A.1 Sintered CuCr (25) (100×) Figure A.2
A.3 Metallographic structure of copper-chromium electrical contacts produced by melt immersion method is shown in Figures A.3 and A.4. Figure A.3 Melt immersion method CuCr (25)
(100×)
JB/T7098—2002
Sintered CuCr (50)
(100X)
Metal immersion method CuCr (50) (100x)
A.4 Metallographic structure of copper-chromium electrical contacts produced by arc melting method is shown in Figure A.5. Figure A.5
Arc melting method CuCr (25) (100×) JB/T7098—2002
A.5 The metallographic structure of copper-chromium electrical contacts produced by vacuum casting is shown in Figure A.6. 2 338
Figure A.6 Vacuum casting method CuCr (25)
Appendix B
(Normative Appendix)
Product inspection sampling table
(100×)
The data quoted in this appendix are partially extracted from GB/T2828 for reference when using this standard, B.1
Secondary normal inspection sampling table (see Table B.1), Table B.1 sampling Sample table
Sampling quantity code
Batch range
(pieces)
1～~25
91～150
151~~280
281~500
501～1200
1201~~3200
Note 1:
Note 2: Ae
Note 3: R.
Special inspection level
Sampling number
Quantity code
Normal inspection subsampling plan
Cumulative sampling
Number of samples
Acceptable quality level (AQL)
Use the first sampling plan below the arrow. If the sample size is greater than or equal to the batch size, the entire batch will be inspected 100%; qualified judgment number:
Unqualified judgment number.
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