CN101707154B - Method for preparing a silver-based electric contact material - Google Patents
Method for preparing a silver-based electric contact material Download PDFInfo
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- CN101707154B CN101707154B CN2009101962794A CN200910196279A CN101707154B CN 101707154 B CN101707154 B CN 101707154B CN 2009101962794 A CN2009101962794 A CN 2009101962794A CN 200910196279 A CN200910196279 A CN 200910196279A CN 101707154 B CN101707154 B CN 101707154B
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Abstract
The invention discloses a method for preparing a silver-based electric contact material, which comprises the following steps of: adopting a method for performing injection and atomization on both solid phase powder and a liquid phase metal to obtain reinforced phase composite powder coated with a metal; and adopting a preparation means of subsequent sintering, hot pressing and squeezing to densify the composite powder so as to form the silver-based electric contact material. In the electric contact material, the reinforced phase form is granular, the reinforced phase average particle size is between 0.1 and 100 mum, and the reinforced phase weight content in the electric contact material is less than or equal to 20 percent. The electric contact material prepared by the method has the advantages of good arc ablation resistance, high conductivity and excellent mechanical properties, and the arc resistance, the conductivity, and the strength of the electric contact material are improved respectively compared with those of a same-system material prepared by the conventional powder metallurgy method.
Description
Technical field
The present invention relates to a kind of method of electrical contact material technical field, specifically, that relate to is a kind of preparation method of silver-based electric contact material.
Background technology
Low-voltage electrical apparatus electricity consumption preparation of contact material is generally powder metallurgic method and internal oxidation, and its prepared flow process is for mixing powder, ball milling, compacting, sintering.Along with improving constantly of application requirements, its preparation method is also abundant gradually now, and high-energy ball milling method is arranged, chemical coating method, and preparation means such as preoxidation, as described below:
1) high-energy ball milling method prepares AgSnO
2The research letter moral Hunan University Of Tianjin Master's thesis of contact material
2) a kind of preparation of silver-tin oxide material CN1425790A
3) the low-voltage electrical apparatus little ordinary telegram worker of electrical contact material cypress material 2007 (3)
The strength of materials height that high energy ball mill method (document 1) prepares, electric property is good, but introduces impurity easily, and is difficult for producing in batches.The material interface intensity of chemistry coating method (document 3) preparation is good, and plasticity is good, is beneficial to processing, and its shortcoming is the technological operation complexity, and operation is various.Preoxidation (document 2) is a kind of new method that occurs recently, and its advantage is that the material interface bond strength is good, is uniformly dispersed, but only is applicable to that oxide particle strengthens series, can not be applied to other electrical contact material systems.
Summary of the invention
Order of the present invention is deficiency and the defective at above-mentioned prior art existence, and a kind of preparation method of silver-based electric contact material is provided, and can be applied to the preparation of most of low-voltage electrical apparatuses with the Ag-based electrical contact material system.
For realizing above-mentioned purpose, the technical solution used in the present invention is: the method that adopts solid phase powder and liquid metal to be total to jet deposition obtains to be coated with the wild phase composite powder of metal, and preparation means densifications such as composite powder employing follow-up sintering hot pressing extruding are shaped.Described contact material, wherein the wild phase form is a particle shape, and the wild phase particle mean size is between 0.1-100 μ m, and the contact material kind can be all low-voltage electrical apparatuses silver-based electric contact material system nowadays, and the wild phase weight content is not more than 20%.
Described wild phase kind can be SnO
2, ZnO, Ni, one or more among the C.
The preparation method of the silver-based electric contact material that the present invention is above-mentioned may further comprise the steps:
1) melting.Component ratio by required preparation material places the graphite crucible melting of Frequency Induction Heating to obtain melt liquid corresponding weight Ag metal derby.
Described melting, its temperature is between 1050-1300 ℃.
2) jet atomization.The elevated pressure nitrogen gas that employing contains the wild phase particle clashes into the Ag metal liquid stream that obtains after the above-mentioned melting, makes it be dispersed into the metal fine drop that contains the wild phase particle, treats that it is cooled to the composite metal powder that obtains to contain the wild phase particle after the room temperature.
Described high pressure, its pressure is at 0.5-10MPa.
The particle mean size of described wild phase particle is between 0.1-100 μ m.
3) with 2) composite metal powder that obtains of step carries out isostatic cool pressing.
Described isostatic cool pressing pressure is at 100MPa-500MPa
4) base substrate after the isostatic cool pressing is carried out sintering and follow-up hot pressing or high temperature insostatic pressing (HIP) densification.
Described sintering and follow-up hot pressing, its sintering temperature are between 700-900 ℃, and sintering time is between 3-7 hour, and hot pressing temperature is between 400-800 ℃, and hot pressing pressure is between 500-800MPa.
Described high temperature insostatic pressing (HIP), its temperature is between 500-900 ℃, and pressure is between 100-200MPa.
5) base substrate that (4) step was obtained carries out hot extrusion.
Described hot extrusion, its temperature is between 500-900 ℃, and extrusion ratio is between 200-400.
The present invention at first adopts the method for jet atomization to obtain the wild phase composite powder that the surface is coated with metal, obtains fine and close electric contact composite material by follow-up hot consolidation and extruding means again.Owing to obtain in the process of composite powder in jet atomization, the wild phase particle is along with gases at high pressure enter in the molten drop, and molten drop cools off at the wild phase particle surface in cooling procedure immediately, thereby forms composite powder.Such composite powder preparation method, compare with traditional powder metallurgy hybrid technique, improved the interface bond strength of wild phase particle and molten drop, and the wild phase particle plays the effect of restriction molten drop grain growth in the drop cooling procedure, thereby reach crystal grain thinning, improve the effect of the strength of materials.Hot consolidation subsequently and pressing method can obtain fully fine and close composite material, and further improve interface bond strength and improve the distribution of wild phase particle in hot consolidation and extrusion process, thereby improve material property.It is good that the contact material that adopts the present invention to prepare has the arc ablation resistance ability, the conductance height, and the advantage of good mechanical performance, its anti-electric arc ability, conductance, intensity are improved than the same system material of prior powder metallurgy method preparation respectively.
Embodiment
Below technical scheme of the present invention is further described, below describe and just be used to understand the present invention, and be not used in the scope of the present invention that limits.
Embodiment one
With preparation 10kg particle mean size is that Ag-Ni20 (weight ratio) contact material that the Ni particle of 1 μ m strengthens is an example
At first 8kg Ag metal is placed the melting of Medium frequency induction graphite crucible, 1050 ℃ of smelting temperatures obtain complete motlten metal liquid.
(promptly adopt the elevated pressure nitrogen gas that contains the wild phase particle to clash into the Ag metal liquid stream that obtains after the above-mentioned melting with the high pressure nitrogen that contains 2kg Ni particle to the Ni particle composite powder that above-mentioned melt liquid enforcement jet atomization obtains to be coated with the Ag metal then, make it be dispersed into the metal fine drop that contains the wild phase particle, treat that it is cooled to the composite metal powder that obtains to contain the wild phase particle after the room temperature), nitrogen gas pressure is 10MPa, and the Ni average particle size is 1 μ m.
Composite powder isostatic cool pressing under 100MPa that jet atomization is obtained obtains pressed compact.
Again pressed compact is carried out sintering and hot pressing, promptly at 900 ℃ of sintering 7h, then at 800 ℃, hot pressing under the 500MPa pressure.
Base substrate behind the hot consolidation is carried out hot extrusion, and extrusion temperature is 500 ℃, and extrusion ratio is 200.
By the said process preparation, can obtain the AgNi10 composite material, the Ni grain graininess is 0.1 μ m.The AgNi10 material conductance that obtains 2.0 μ Ω .cm, intensity 358MPa, density 10.2g/cm
3
Embodiment two
With preparation 10kg particle mean size is that Ag-C4 (weight ratio) contact material that the graphite granule of 100 μ m strengthens is an example
At first 9.6kg Ag metal is placed the melting of Medium frequency induction graphite crucible, 1300 ℃ of smelting temperatures obtain complete motlten metal liquid.
With the high pressure nitrogen that contains the 0.4kg graphite granule above-mentioned melt liquid is implemented the graphite composite powder that jet atomization obtains to be coated with the Ag metal then, nitrogen gas pressure is 5MPa, and the graphite granule granularity is 100 μ m.
Composite powder isostatic cool pressing under 100MPa that jet atomization is obtained obtains pressed compact.
Again pressed compact is carried out high temperature insostatic pressing (HIP), promptly at 900 ℃, high temperature insostatic pressing (HIP) under the 100MPa pressure.
Base substrate behind the high temperature insostatic pressing (HIP) is carried out hot extrusion, and extrusion temperature is 600 ℃, and extrusion ratio is 300.
By the said process preparation, can obtain the AgC4 composite material, the graphite granule granularity is 100 μ m.The AgC4 material conductance that obtains 2.3 μ Ω .cm, hardness 45HV, density 8.9g/cm
3
Embodiment three
With preparation 10kg particle mean size is the SnO of 0.1 μ m
2The Ag-SnO that particle strengthens
210 (weight ratio) contact material is an example
At first 9kg Ag metal is placed the melting of Medium frequency induction graphite crucible, 1100 ℃ of smelting temperatures obtain complete motlten metal liquid.
Then with containing 1kgSnO
2The high pressure nitrogen of particle is implemented the SnO that jet atomization obtains to be coated with the Ag metal to above-mentioned melt liquid
2Particle composite powder, nitrogen gas pressure are 0.5MPa, SnO
2Grain graininess is 0.1 μ m.
Composite powder isostatic cool pressing under 240MPa that jet atomization is obtained obtains pressed compact.
Again pressed compact is carried out high temperature insostatic pressing (HIP), promptly at 500 ℃, high temperature insostatic pressing (HIP) under the 200MPa pressure.
Base substrate behind the high temperature insostatic pressing (HIP) is carried out hot extrusion, and extrusion temperature is 700 ℃, and extrusion ratio is 350.
By the said process preparation, can obtain AgSnO
210 composite materials, SnO
2Grain graininess is 0.1 μ m.Obtain Ag-SnO
210 resistivity of material, 3.2 μ Ω .cm, intensity 350MPa, density 10.0g/cm
3
Embodiment four
With preparation 10kg particle mean size is that Ag-ZnO10 (weight ratio) contact material that the ZnO particle of 1 μ m strengthens is an example
At first 9kg Ag metal is placed the melting of Medium frequency induction graphite crucible, 1150 ℃ of smelting temperatures obtain complete motlten metal liquid.
With the high pressure nitrogen that contains 1kg ZnO particle above-mentioned melt liquid is implemented the ZnO particle composite powder that jet atomization obtains to be coated with the Ag metal then, nitrogen gas pressure is 5MPa, and the ZnO grain graininess is 1 μ m.
Composite powder isostatic cool pressing under 300MPa that jet atomization is obtained obtains pressed compact.
Again pressed compact is carried out sintering and hot pressing, promptly at 900 ℃ of sintering 5h, then at 750 ℃, hot pressing under the 800MPa pressure.Base substrate after the sintering hot pressing is carried out hot extrusion, and extrusion temperature is 600 ℃, and extrusion ratio is 400.
By the said process preparation, can obtain the AgZnO10 composite material, the ZnO grain graininess is 1 μ m.The AgZnO10 resistivity of material that obtains 2.7 μ Ω .cm, hardness 75HV, density 9.5g/cm
3
Embodiment five
With preparation 10kg particle mean size is ZnO particle and the SnO of 1 μ m
2The Ag-ZnO4-SnO that confusion strengthens
26 (weight ratio) contact material is an example
At first 9kg Ag metal is placed the melting of Medium frequency induction graphite crucible, 1150 ℃ of smelting temperatures obtain complete motlten metal liquid.
Then with containing 0.4kg ZnO and 0.6kgSnO
2The high pressure nitrogen of particle is implemented ZnO particle and the SnO that jet atomization obtains to be coated with the Ag metal to above-mentioned melt liquid
2Particle composite powder, nitrogen gas pressure are 5MPa, ZnO and SnO
2Grain graininess is 1 μ m.
Composite powder isostatic cool pressing under 400MPa that jet atomization is obtained obtains pressed compact.
Again pressed compact is carried out sintering and hot pressing, promptly at 800 ℃ of sintering 5h, then at 400 ℃, hot pressing under the 500MPa pressure.
Base substrate after the sintering hot pressing is carried out hot extrusion, and extrusion temperature is 900 ℃, and extrusion ratio is 300.
By the said process preparation, can obtain Ag-ZnO4-SnO
26 composite materials, ZnO and SnO
2Grain graininess is 3 μ m.The resistivity of material that obtains 2.5 μ Ω .cm, hardness 85HV, density 9.7g/cm
3
Embodiment six
With preparation 10kg particle mean size is that the ZnO particle of 5 μ m and Ag-ZnO2-Ni8 (weight ratio) contact material of 1 μ m Ni confusion enhancing are example
At first 9kg Ag metal is placed the melting of Medium frequency induction graphite crucible, 1150 ℃ of smelting temperatures obtain complete motlten metal liquid.
With the high pressure nitrogen that contains 0.2kg ZnO and 0.8kgNi particle above-mentioned melt liquid is implemented ZnO particle and the Ni particle composite powder that jet atomization obtains to be coated with the Ag metal then, nitrogen gas pressure is 3MPa, and the ZnO grain graininess is that 5 μ m and Ni grain graininess are 1 μ m.
Composite powder isostatic cool pressing under 500MPa that jet atomization is obtained obtains pressed compact.
Again pressed compact is carried out high temperature insostatic pressing (HIP), hip temperature is 700 ℃, and pressure is 150MPa.
Base substrate behind the high temperature insostatic pressing (HIP) is carried out hot extrusion, and extrusion temperature is 600 ℃, and extrusion ratio is 300.
By the said process preparation, can obtain the Ag-ZnO2-Ni8 composite material, the ZnO grain graininess is 5 μ m, the Ni grain graininess is 1 μ m.The Ag-ZnO2-Ni8 resistivity of material that obtains 2.3 μ Ω .cm, hardness 98HV, density 9.8g/cm
3
Embodiment seven
Ag-8Ni-1SnO with the enhancing of preparation 10kg 1 μ m particle
2-1ZnO (weight ratio) contact material is an example
At first 9kg Ag metal is placed the melting of Medium frequency induction graphite crucible, 1250 ℃ of smelting temperatures obtain complete motlten metal liquid.
Then with containing 0.8kg Ni particle, 0.1kgZnO particle, 0.1kgSnO
2The high pressure nitrogen of particle is implemented the Ni that jet atomization obtains to be coated with the Ag metal, SnO to above-mentioned melt liquid
2With ZnO particle composite powder, nitrogen gas pressure is 10MPa, and grain graininess is 1 μ m.
Composite powder isostatic cool pressing under 300MPa that jet atomization is obtained obtains pressed compact.
Again pressed compact is carried out sintering and hot pressing, promptly at 850 ℃ of sintering 5h, then at 750 ℃, hot pressing under the 600MPa pressure.
Base substrate after the sintering hot pressing is carried out hot extrusion, and extrusion temperature is 750 ℃, and extrusion ratio is 200.
By the said process preparation, can obtain Ag-8Ni-1SnO
2-1ZnO composite material, grain graininess are 1 μ m.Compare the Ag-8Ni-1SnO of prior powder metallurgy method preparation
2-1ZnO material, the Ag-8Ni-1SnO that obtains
2-1ZnO resistivity of material 2.4 μ Ω .cm, hardness 103HV, density 9.6g/cm
3
Claims (9)
1. the preparation method of a silver-based electric contact material, it is characterized in that, the method that adopts solid phase powder and liquid metal to be total to jet atomization obtains to be coated with the wild phase composite powder of metal, and composite powder is adopted the fine and close shaping of follow-up sintering hot pressing extruding preparation means; Described contact material, wherein the wild phase form is a particle shape, and the wild phase particle mean size is between 0.1-100 μ m, and the wild phase weight content is less than or equal to 20% in the contact material; Described preparation method specifically may further comprise the steps:
1) component ratio by required preparation material places the graphite crucible melting of Frequency Induction Heating to obtain melt liquid corresponding weight Ag metal derby;
2) adopt the elevated pressure nitrogen gas that contains the wild phase particle to clash into the Ag metal liquid stream that obtains after the above-mentioned melting, make it be dispersed into the metal fine drop that contains the wild phase particle, treat that its cooling back obtains to contain the wild phase composite powder of wild phase particle;
3) with 2) the wild phase composite powder that obtains of step carries out isostatic cool pressing;
4) base substrate after the isostatic cool pressing is carried out sintering and follow-up hot pressing or high temperature insostatic pressing (HIP) densification;
5) with 4) base substrate behind the hot consolidation carries out hot extrusion.
2. the preparation method of silver-based electric contact material according to claim 1 is characterized in that, described wild phase is SnO
2, ZnO, Ni, one or more among the C.
3. the preparation method of silver-based electric contact material according to claim 1 is characterized in that, the 1st) in the step, described melting, its temperature is between 1050-1300 ℃.
4. the preparation method of silver-based electric contact material according to claim 1 is characterized in that, the 2nd) in the step, described high pressure, its pressure is at 0.5-10MPa.
5. the preparation method of silver-based electric contact material according to claim 1 is characterized in that, the 2nd) in the step, the particle mean size of described wild phase particle is between 0.1-100 μ m.
6. the preparation method of silver-based electric contact material according to claim 1 is characterized in that, the 3rd) in the step, described isostatic cool pressing pressure is at 100-500MPa.
7. the preparation method of silver-based electric contact material according to claim 1, it is characterized in that, the 4th) in the step, described sintering and follow-up hot pressing, its sintering temperature is between 700-900 ℃, sintering time is between 3-7 hour, and hot pressing temperature is between 400-800 ℃, and hot pressing pressure is between 500-800MPa.
8. the preparation method of silver-based electric contact material according to claim 1 is characterized in that, the 4th) in the step, described high temperature insostatic pressing (HIP), its temperature is between 500-900 ℃, and pressure is between 100-200MPa.
9. the preparation method of silver-based electric contact material according to claim 1 is characterized in that, the 5th) in the step, described hot extrusion, its temperature is between 500-900 ℃, and extrusion ratio is between 200-400.
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Families Citing this family (5)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN101944397A (en) * | 2010-06-29 | 2011-01-12 | 福达合金材料股份有限公司 | Silver-based ceramic electric contact material and preparation method thereof |
| CN102876913A (en) * | 2012-09-07 | 2013-01-16 | 重庆川仪自动化股份有限公司 | Sulfide-containing self-lubricating sliding electrical contact material |
| CN103045895A (en) * | 2013-01-17 | 2013-04-17 | 上海大趋金属科技有限公司 | Electric contact material and preparation method thereof |
| CN105742083A (en) * | 2014-12-11 | 2016-07-06 | 福达合金材料股份有限公司 | Composite electric contact material with carbon nanotube enhancement, and preparation process thereof |
| CN108103339A (en) * | 2017-12-18 | 2018-06-01 | 浙江工业大学 | A kind of preparation method of silver-based barium titanate composited contact material |
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| CN87106831A (en) * | 1986-09-24 | 1988-04-13 | 艾尔坎国际有限公司 | The composition of granular metal |
| CN1117276A (en) * | 1993-02-06 | 1996-02-21 | 欧斯普瑞金属有限公司 | Production of powder |
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| CN101202169A (en) * | 2007-10-23 | 2008-06-18 | 福达合金材料股份有限公司 | Method of preparing novel silver tin oxide silk electrical contact material |
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2009
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| CN87106831A (en) * | 1986-09-24 | 1988-04-13 | 艾尔坎国际有限公司 | The composition of granular metal |
| CN1117276A (en) * | 1993-02-06 | 1996-02-21 | 欧斯普瑞金属有限公司 | Production of powder |
| US6059853A (en) * | 1993-02-06 | 2000-05-09 | Behr South Africa (Pty) Ltd. | Production of powder |
| CN1519991A (en) * | 2002-12-27 | 2004-08-11 | ������-�ֿ˹����ɷ�����˾ | Composite material for mfg. electrical contacts and process for its prepn. |
| CN101202169A (en) * | 2007-10-23 | 2008-06-18 | 福达合金材料股份有限公司 | Method of preparing novel silver tin oxide silk electrical contact material |
Non-Patent Citations (2)
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| JP特开平4-228531A 1992.08.18 |
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