CN114875267A - Preparation method of silver-based electric contact material with adjustable work function - Google Patents
Preparation method of silver-based electric contact material with adjustable work function Download PDFInfo
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- CN114875267A CN114875267A CN202210553417.5A CN202210553417A CN114875267A CN 114875267 A CN114875267 A CN 114875267A CN 202210553417 A CN202210553417 A CN 202210553417A CN 114875267 A CN114875267 A CN 114875267A
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- 239000000463 material Substances 0.000 title claims abstract description 57
- 238000002360 preparation method Methods 0.000 title claims abstract description 12
- BQCADISMDOOEFD-UHFFFAOYSA-N Silver Chemical compound [Ag] BQCADISMDOOEFD-UHFFFAOYSA-N 0.000 title claims abstract description 11
- 229910052709 silver Inorganic materials 0.000 title claims abstract description 11
- 239000004332 silver Substances 0.000 title claims abstract description 11
- 238000000034 method Methods 0.000 claims abstract description 33
- 230000003647 oxidation Effects 0.000 claims abstract description 21
- 238000007254 oxidation reaction Methods 0.000 claims abstract description 21
- 229910052776 Thorium Inorganic materials 0.000 claims abstract description 18
- 229910052684 Cerium Inorganic materials 0.000 claims abstract description 17
- 229910052788 barium Inorganic materials 0.000 claims abstract description 17
- 230000006698 induction Effects 0.000 claims abstract description 14
- 229910017750 AgSn Inorganic materials 0.000 claims description 22
- 239000000956 alloy Substances 0.000 claims description 22
- 229910045601 alloy Inorganic materials 0.000 claims description 22
- 238000003723 Smelting Methods 0.000 claims description 20
- 239000000843 powder Substances 0.000 claims description 17
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 claims description 5
- 238000009472 formulation Methods 0.000 claims description 5
- 239000000203 mixture Substances 0.000 claims description 5
- 229910052760 oxygen Inorganic materials 0.000 claims description 5
- 239000001301 oxygen Substances 0.000 claims description 5
- 239000002243 precursor Substances 0.000 claims description 5
- 238000005303 weighing Methods 0.000 claims description 4
- 238000002679 ablation Methods 0.000 abstract description 7
- 238000002844 melting Methods 0.000 abstract description 7
- 230000008018 melting Effects 0.000 abstract description 7
- 230000000694 effects Effects 0.000 abstract description 4
- 230000003628 erosive effect Effects 0.000 abstract description 4
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 8
- 229910002804 graphite Inorganic materials 0.000 description 8
- 239000010439 graphite Substances 0.000 description 8
- 239000002994 raw material Substances 0.000 description 8
- 238000011156 evaluation Methods 0.000 description 4
- 230000001590 oxidative effect Effects 0.000 description 4
- 239000012856 weighed raw material Substances 0.000 description 4
- 238000006243 chemical reaction Methods 0.000 description 3
- 230000033228 biological regulation Effects 0.000 description 2
- 239000002131 composite material Substances 0.000 description 2
- 230000001105 regulatory effect Effects 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 1
- 229910052797 bismuth Inorganic materials 0.000 description 1
- 230000015556 catabolic process Effects 0.000 description 1
- 238000012512 characterization method Methods 0.000 description 1
- 230000001276 controlling effect Effects 0.000 description 1
- 229910052802 copper Inorganic materials 0.000 description 1
- 239000013078 crystal Substances 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000006731 degradation reaction Methods 0.000 description 1
- 238000009826 distribution Methods 0.000 description 1
- 230000004927 fusion Effects 0.000 description 1
- 229910052759 nickel Inorganic materials 0.000 description 1
- 230000002035 prolonged effect Effects 0.000 description 1
- 230000035939 shock Effects 0.000 description 1
- 238000003466 welding Methods 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C1/00—Making non-ferrous alloys
- C22C1/10—Alloys containing non-metals
- C22C1/1078—Alloys containing non-metals by internal oxidation of material in solid state
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C1/00—Making non-ferrous alloys
- C22C1/02—Making non-ferrous alloys by melting
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C32/00—Non-ferrous alloys containing at least 5% by weight but less than 50% by weight of oxides, carbides, borides, nitrides, silicides or other metal compounds, e.g. oxynitrides, sulfides, whether added as such or formed in situ
- C22C32/001—Non-ferrous alloys containing at least 5% by weight but less than 50% by weight of oxides, carbides, borides, nitrides, silicides or other metal compounds, e.g. oxynitrides, sulfides, whether added as such or formed in situ with only oxides
- C22C32/0015—Non-ferrous alloys containing at least 5% by weight but less than 50% by weight of oxides, carbides, borides, nitrides, silicides or other metal compounds, e.g. oxynitrides, sulfides, whether added as such or formed in situ with only oxides with only single oxides as main non-metallic constituents
- C22C32/0021—Matrix based on noble metals, Cu or alloys thereof
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C5/00—Alloys based on noble metals
- C22C5/06—Alloys based on silver
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
- H01H1/00—Contacts
- H01H1/02—Contacts characterised by the material thereof
- H01H1/021—Composite material
- H01H1/023—Composite material having a noble metal as the basic material
- H01H1/0237—Composite material having a noble metal as the basic material and containing oxides
- H01H1/02372—Composite material having a noble metal as the basic material and containing oxides containing as major components one or more oxides of the following elements only: Cd, Sn, Zn, In, Bi, Sb or Te
- H01H1/02376—Composite material having a noble metal as the basic material and containing oxides containing as major components one or more oxides of the following elements only: Cd, Sn, Zn, In, Bi, Sb or Te containing as major component SnO2
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
- H01H11/00—Apparatus or processes specially adapted for the manufacture of electric switches
- H01H11/04—Apparatus or processes specially adapted for the manufacture of electric switches of switch contacts
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- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Mechanical Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Manufacturing & Machinery (AREA)
- Composite Materials (AREA)
- Manufacture Of Alloys Or Alloy Compounds (AREA)
- Powder Metallurgy (AREA)
- Contacts (AREA)
Abstract
The invention discloses a preparation method of a silver-based electric contact material with adjustable work function, which takes Th, Ce or Ba as a work function regulator and adopts a medium-frequency induction melting method combined with an internal oxidation method to prepare AgSnO with adjustable work function 2 A contact material. The method of the invention can improve the traditional AgSnO 2 The surface work function of the contact material reduces the surface temperature rise effect and the ablation degree, and improves the arc erosion resistance and the service cycle of the electric service life.
Description
Technical Field
The invention relates to preparation of an electric contact material, in particular to a preparation method of a silver-based electric contact material with adjustable work function, which is applied to the fields of nano electric contact, new energy low-voltage switching devices and the like.
Background
The silver-based composite contact material as an electric connection element material is widely applied to the fields of various light and heavy load aerospace electrical appliances, high and low voltage electrical appliances, automobile electrical appliances, household electrical appliances and the like due to good performances of electric wear resistance, fusion welding resistance, conductivity, small contact resistance, stability and the like. However, conventional AgSnO 2 The service life of the contact material is prone to fail in advance under the combined action of arc heat and force, and even serious safety accidents occur. The reason for this is that the arc formed in the breaking process of the contact material transfers thousands of heat to the surface of the contact, which causes severe surface ablation, and aggravates the degradation of the microstructure and the electrical contact performance of the surface of the contact material. It can be found that the arc ablation can be reduced little by changing the type of working atmosphere, the arc extinguishing mode or the shape of the contact surface. The work function of the contact material is an intrinsic key factor determining arc erosion. Research has shown that the work function of the material surface directly affects the emission capability of the thermal electrons on the contact material surface, and further affects the temperature field distribution condition of the contact surface, and the thermal shock and ablation degree of the thermal electrons on the contact surface. The work function of the contact surface is reduced by regulation, so that the thermionic emission capability is improved, the temperature of the contact surface is reduced, the temperature rise effect and the ablation degree of the contact surface are further reduced, and the electric service life performance and the safety and reliability of the contact material are prolonged. The existing method for regulating and controlling the work function of the contact surface mainly comprises the steps of crystal orientation, surface defects, adsorbed atoms, step density, material types and the like, wherein the former four methods belong to the regulation and control on a microscopic level in the preparation technology and are difficult to accurately regulate and control, and the material types are key factors influencing the surface work function of a system. The relevant literature shows that in AgSnO 2 The third component (such as Bi, Cu, Ni and the like) introduced into the contact material system contributes to AgSnO 2 Physics of contact materialPerformance and electrical life service performance. On the other hand, from the research idea of adjustable work function, a specific work function regulator is introduced into the internal oxidation preparation technology to achieve AgSnO 2 The research on the purpose of optimizing the comprehensive performance of the contact material is rarely reported.
Disclosure of Invention
The invention aims to solve the technical problem of providing AgSnO with adjustable work function 2 The preparation method of the contact material adopts the combination of intermediate frequency induction melting and internal oxidation to prepare AgSnO with adjustable work function by taking Th, Ce or Ba as a work function regulator 2 A contact material. The product prepared by the method can be used for improving the traditional AgSnO 2 The surface work function of the contact material reduces the surface temperature rise effect and the ablation degree, and improves the arc erosion resistance and the service cycle of the electric service life. The invention provides a new idea for preparing a novel oxide reinforced silver-based composite contact material with a long service life in the field of new energy.
In order to solve the technical problems, the invention adopts the following solution:
a preparation method of a silver-based electric contact material with adjustable work function specifically comprises the following steps:
(1) work function adjustable modified AgSn alloy
One of Th, Ce, Ba and the like is used as a work function regulator, a Ni component is used as a grain refiner, and a medium-frequency induction melting method is adopted to obtain a modified AgSn alloy ingot with uniform structure. Weighing a certain amount of raw materials such as Ag ingot, Sn ingot, Th powder, Ce powder, Ba powder, Ni powder and the like in a vacuum glove box environment (the detailed formula is shown in table 1), and introducing the weighed raw materials into a graphite crucible. And then, placing the graphite crucible loaded with the raw materials into a medium-frequency induction smelting furnace, setting the corresponding smelting temperature (1000-1400 ℃), fully reacting for a certain smelting time (8-12 h), finally obtaining a Th, Ce or Ba modified AgSn alloy ingot with adjustable work function, and performing work function representation on the obtained modified AgSn alloy ingot.
TABLE 1 component formulation and smelting process
(2) Work function adjustable modified AgSnO 2 Contact material
Preparing work function adjustable modified AgSnO by adopting prepared Th, Ce or Ba modified AgSn alloy cast ingot as precursor through internal oxidation process 2 A contact material. According to the calculation of a thermodynamic Gibbs free energy function, preferably designing a thermodynamically feasible oxygen partial pressure parameter value (3-7 MPa), setting a corresponding internal oxidation temperature (600-900 ℃), and fully oxidizing in a certain internal oxidation time (10-24 h) completely to finally obtain the modified AgSnO with adjustable work function 2 A contact material. Finally, the modified AgSnO with adjustable work function prepared by the process 2 The contact material is subjected to performance evaluation such as contact temperature rise, electric service life capability and the like.
The invention has the advantages of innovation and beneficial effect
Based on the research idea of adjusting the work function of the surface of the material, the invention provides AgSnO with adjustable work function by utilizing the respective technical advantages of the medium-frequency induction melting method and the internal oxidation method 2 The preparation method of the contact material comprises the steps of forming a Th, Ce or Ba modified AgSn alloy with uniform tissue by a medium-frequency induction melting method, and optimally preparing Th, Ce or Ba modified AgSnO with adjustable work function by an internal oxidation process 2 Contact material, and effectively regulated and controlled prepared modified AgSnO 2 The surface work function of the contact material reduces the surface temperature rise effect and the ablation degree, improves the arc erosion resistance of the contact material, and improves the service capacity of the electrical life of the contact material.
Detailed Description
The following describes the implementation of the present invention in detail by means of specific embodiments.
Example 1:
(1) work function adjustable modified AgSn alloy
The modified AgSn alloy ingot with uniform tissue is obtained by taking Th, Ce or Ba as a work function regulator and Ni components as grain refiners and adopting a medium-frequency induction smelting method. In a vacuum glove box environment, a certain amount of raw materials such as Ag ingot, Sn ingot, Th powder, Ce powder, Ba powder, Ni powder and the like are weighed (the detailed formula is shown in table 2), and the weighed raw materials are introduced into a graphite crucible. Then, the graphite crucible loaded with the raw materials is placed into a medium-frequency induction smelting furnace, the corresponding smelting temperature (1000 ℃) is set, and the reaction is fully carried out in certain smelting time (8h), and finally the Th, Ce or Ba modified AgSn alloy cast ingot with adjustable work function is obtained.
TABLE 2 component formulation and smelting process
(2) Work function adjustable modified AgSnO 2 Contact material
Preparing work function adjustable modified AgSnO by adopting prepared Th, Ce or Ba modified AgSn alloy cast ingot as precursor through internal oxidation process 2 A contact material. According to the calculation of a thermodynamic Gibbs free energy function, preferably designing a thermodynamically feasible oxygen partial pressure parameter value (3MPa), setting a corresponding internal oxidation temperature (900 ℃), and fully oxidizing for a certain internal oxidation time (10h) completely to finally obtain the modified AgSnO with adjustable work function 2 A contact material. Finally, the modified AgSnO with adjustable work function prepared by the process 2 The contact material is subjected to performance evaluation such as contact temperature rise, electric service life capability and the like.
Example 2:
(1) work function adjustable modified AgSn alloy
And (3) obtaining the modified AgSn alloy ingot with uniform tissue by using Th, Ce or Ba as a work function regulator and Ni as a grain refiner through a medium-frequency induction melting method. Weighing a certain amount of raw materials such as Ag ingot, Sn ingot, Th powder, Ce powder, Ba powder, Ni powder and the like in a vacuum glove box environment (the detailed formula is shown in table 3), and introducing the weighed raw materials into a graphite crucible. Then, the graphite crucible loaded with the raw materials is placed into a medium-frequency induction smelting furnace, the corresponding smelting temperature (1400 ℃) is set, and the reaction is fully carried out in a certain smelting time (12h), and finally the Th, Ce or Ba modified AgSn alloy cast ingot with adjustable work function is obtained.
TABLE 3 component formulation and smelting process
(2) Work function adjustable modified AgSnO 2 Contact material
Preparing work function adjustable modified AgSnO by adopting prepared Th, Ce or Ba modified AgSn alloy cast ingot as precursor through internal oxidation process 2 A contact material. According to the calculation of a thermodynamic Gibbs free energy function, preferably designing a thermodynamically feasible oxygen partial pressure parameter value (7MPa), setting a corresponding internal oxidation temperature (650 ℃), and fully oxidizing within a certain internal oxidation time (24h) to obtain the modified AgSnO with adjustable work function 2 A contact material. Finally, the modified AgSnO with adjustable work function prepared by the process 2 The contact material is subjected to performance evaluation such as contact temperature rise, electric service life capability and the like.
Example 3:
(1) work function adjustable modified AgSn alloy
And (3) obtaining the modified AgSn alloy ingot with uniform tissue by using Th, Ce or Ba as a work function regulator and Ni as a grain refiner through a medium-frequency induction melting method. Weighing a certain amount of raw materials such as Ag ingot, Sn ingot, Th powder, Ce powder, Ba powder, Ni powder and the like in a vacuum glove box environment (the detailed formula is shown in table 4), and introducing the weighed raw materials into a graphite crucible. Then, the graphite crucible loaded with the raw materials is placed into a medium-frequency induction smelting furnace, the corresponding smelting temperature (1150 ℃) is set, and the reaction is fully carried out in a certain smelting time (10h), and finally the Th, Ce or Ba modified AgSn alloy cast ingot with adjustable work function is obtained.
TABLE 4 component formulation and smelting process
(2) Work function adjustable modified AgSnO 2 Contact material
Preparing work function adjustable modified AgSnO by adopting prepared Th, Ce or Ba modified AgSn alloy cast ingot as precursor through internal oxidation process 2 A contact material. According to heat powerCalculating a Gibbs free energy function, preferably designing a thermodynamically feasible oxygen partial pressure parameter value (5MPa), setting a corresponding internal oxidation temperature (820 ℃), and fully oxidizing in a certain internal oxidation time (16h) to obtain the modified AgSnO with adjustable work function 2 A contact material. Finally, the modified AgSnO with adjustable work function prepared by the process 2 The contact material is subjected to performance evaluation such as contact temperature rise, electric service life capability and the like.
As is clear from Table 5, the modified AgSnO obtained in examples 1 to 3 2 The work function of the contact material is obviously lower than that of the traditional AgSnO 2 . The contact temperature rise and the electric service life capability are effectively improved, and data support is provided for further exerting long service life performance and reliability application in the field of electric contact materials.
TABLE 5 modified AgSnO with tunable work function 2 Characterization of contact temperature rise and electric service life capability of contact material
Claims (4)
2. The method for preparing the silver-based electric contact material with the adjustable work function according to claim 1, which comprises the following steps:
1) preparation of modified AgSn alloy with adjustable work function
Taking one of Th, Ce or Ba as a work function regulator, taking Ni as a grain refiner, and obtaining a modified AgSn alloy ingot with uniform structure by adopting a medium-frequency induction smelting method;
2) preparation of modified AgSnO with adjustable work function 2 Contact material
Preparing modified AgSnO with adjustable work function by adopting the modified AgSn alloy ingot prepared in the step 1) as a precursor and adopting an internal oxidation process 2 A contact material.
3. The method for preparing the silver-based electric contact material with the adjustable work function according to claim 2, wherein the step 1) is specifically as follows:
weighing Ag ingots, Sn ingots, Ni powder and a work function regulator in a vacuum glove box environment, placing the components in a medium-frequency induction furnace, setting the smelting temperature to be 1000-1400 ℃, and smelting for 8-12 hours to finally obtain the modified AgSn alloy ingot with uniform tissue.
4. The method for preparing the silver-based electric contact material with the adjustable work function according to claim 2, wherein in the step 2), the AgSnO with the adjustable work function and the modified function is prepared by adopting an internal oxidation process 2 The specific conditions of the contact material are as follows: the oxygen partial pressure parameter value is 3-7 MPa, the internal oxidation temperature is 600-900 ℃, and the internal oxidation time is 10-24 h.
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CN202210553417.5A CN114875267A (en) | 2022-05-20 | 2022-05-20 | Preparation method of silver-based electric contact material with adjustable work function |
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Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4011052A (en) * | 1972-03-15 | 1977-03-08 | Square D Company | Electrical contact material and process |
CN1035139A (en) * | 1988-03-29 | 1989-08-30 | 中国有色金属工业总公司昆明贵金属研究所 | Super perforance silver base alloy for electric contact |
CN105895418A (en) * | 2016-04-16 | 2016-08-24 | 苏州思创源博电子科技有限公司 | Preparation method of silver based electric contact material |
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- 2022-05-20 CN CN202210553417.5A patent/CN114875267A/en active Pending
Patent Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4011052A (en) * | 1972-03-15 | 1977-03-08 | Square D Company | Electrical contact material and process |
CN1035139A (en) * | 1988-03-29 | 1989-08-30 | 中国有色金属工业总公司昆明贵金属研究所 | Super perforance silver base alloy for electric contact |
CN105895418A (en) * | 2016-04-16 | 2016-08-24 | 苏州思创源博电子科技有限公司 | Preparation method of silver based electric contact material |
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