CN-121976078-A - Method for preparing silver tin oxide indium oxide by constant-temperature and constant-pressure internal oxidation and wire particle recombination molding and electric contact material prepared by same

Abstract

The application discloses a method for preparing silver tin oxide indium oxide by constant-temperature and constant-pressure internal oxidation and wire particle recombination molding and an electric contact material prepared by the method, and relates to the field of silver-based electric contact materials. The silver tin oxide indium oxide electric contact material is prepared by adopting a mode of combining a constant-temperature and constant-pressure internal oxidation process and a wire grain recombination forming process, the obtained silver tin oxide indium oxide electric contact material has no problems of oxide enrichment, silver-based bright band area, poor oxide area and overhigh hardness, and the silver tin oxide indium oxide electric contact material has uniform metallographic structure distribution, moderate hardness, good processing performance and excellent electric performance.

Inventors

• LIU TIANJUN
• PAN ZHIXIONG
• XU FUTAI
• LU XIAODONG
• LI YUANLIANG
• LI GUOFENG

Assignees

• 佛山通宝精密合金股份有限公司

Dates

Publication Date

20260505

Application Date

20251229

Claims (10)

1. 1. The method for preparing silver tin oxide indium oxide by constant-temperature and constant-pressure internal oxidation and wire particle recombination molding is characterized by comprising the following steps: s1, taking 6-12% of tin ingots, 2.5-4.5% of indium ingots, 0.3-1% of additives and the balance of silver according to weight percentage, smelting and casting into tin-indium alloy spindles, and then carrying out surface impurity removal treatment on the tin-indium alloy spindles, wherein the additives adopt at least one of copper, bismuth, antimony, nickel and ytterbium; s2, preheating and extruding the silver-tin-indium alloy spindle obtained in the step S1 in an ammonia decomposition atmosphere to obtain a silver-tin-indium alloy wire rod, and then sequentially drawing and punching the silver-tin-indium alloy wire rod to obtain silver-tin-indium alloy wire particles A with the length of 10 mm-12 mm; s3, carrying out constant-temperature and constant-pressure internal oxidation on the silver-tin-indium alloy wire particles A obtained in the step S2 to obtain silver-tin-indium oxide wire particles A, wherein the furnace temperature is controlled to be 700 ℃ plus or minus 10 ℃, and pure oxygen with the pressure of 0.3MPa plus or minus 0.01MPa is filled after the furnace is emptied; s4, forming the silver tin oxide indium oxide wire particles A obtained by the constant temperature and constant pressure internal oxidation in the step S3 according to the pressure of 400-800 MPa to obtain a silver tin oxide indium oxide spindle A; s5, carrying out heat preservation sintering on the silver tin oxide indium oxide spindle A obtained in the step S4 at 880+/-10 ℃, and then extruding, drawing and punching to obtain silver tin oxide indium oxide wire particles B with the length of 10 mm-12 mm; s6, carrying out line grain recombination on the silver tin oxide indium oxide line grains B obtained in the step S5, specifically, forming the silver tin oxide indium oxide spindle B according to the pressure of 400-800 MPa, carrying out heat preservation sintering on the silver tin oxide indium oxide spindle B at 880+/-10 ℃, and then extruding and drawing to obtain the silver tin oxide indium oxide electric contact material.
2. 2. The method for preparing silver tin oxide indium oxide by constant temperature and constant pressure internal oxidation and wire grain recombination molding according to claim 1 is characterized in that in S2, the preheating process is controlled to be 650 ℃ plus or minus 50 ℃ for 1.5-2 hours, the extrusion process is controlled to be 250-350, and the wire diameter of silver tin indium alloy wires is controlled to be phi 4.5-phi 5.5mm.
3. 3. The method for preparing silver tin oxide indium oxide by constant temperature and constant pressure internal oxidation and wire grain recombination molding according to claim 1 is characterized in that in S2, after the silver tin indium alloy wire is drawn to a wire diameter specification of phi 1.0 mm-phi 1.4mm, the silver tin indium alloy wire grain A with the length of 10 mm-12 mm is punched.
4. 4. The method for preparing silver tin oxide indium oxide by constant temperature and constant pressure internal oxidation and wire particle recombination molding according to claim 1, wherein in S3, the time of constant temperature and constant pressure internal oxidation is controlled to be 15-30 h.
5. 5. The method for preparing silver tin oxide indium oxide by constant temperature and constant pressure internal oxidation and wire particle recombination molding according to claim 1, wherein in S4, before pressure molding, surface impurity removal is carried out on the silver tin oxide indium oxide wire particle A obtained by the constant temperature and constant pressure internal oxidation in the step S3.
6. 6. The method for preparing silver tin oxide indium oxide by constant temperature and constant pressure internal oxidation and wire particle recombination molding according to claim 1, wherein in S5, the sintering time is 6.5h-7.5h.
7. 7. The method for preparing silver tin oxide indium oxide by constant temperature and constant pressure internal oxidation and wire particle recombination molding according to claim 1 is characterized in that in S5, silver tin oxide indium oxide wire A with the wire diameter of phi 4.5 mm-phi 5.5mm is extruded according to the extrusion ratio of 250-350, then the silver tin oxide indium oxide wire A is drawn into wire with the wire diameter of phi 1.4 mm-phi 1.8mm, and finally the wire is punched to obtain silver tin oxide indium oxide wire particles B with the length of 10 mm-12 mm.
8. 8. The method for preparing silver tin oxide indium oxide by constant temperature and constant pressure internal oxidation and wire particle recombination molding according to claim 1, wherein in S6, before the silver tin oxide indium oxide wire particle B is subjected to pressure molding, surface impurity removal is performed on the silver tin oxide indium oxide wire particle B.
9. 9. The method for preparing silver tin oxide indium oxide by constant temperature and constant pressure internal oxidation and wire particle recombination molding according to claim 1, wherein in S6, the sintering time is 6.5h-7.5h.
10. 10. An electrical contact material characterized in that the material is prepared by the method for preparing silver tin oxide indium oxide by constant temperature and constant pressure internal oxidation and wire particle recombination molding according to any one of claims 1-9.

Description

Method for preparing silver tin oxide indium oxide by constant-temperature and constant-pressure internal oxidation and wire particle recombination molding and electric contact material prepared by same Technical Field The application relates to the field of silver-based electric contact materials, in particular to a method for preparing silver tin oxide indium oxide by constant-temperature and constant-pressure internal oxidation and wire particle recombination molding and an electric contact material prepared by the method. Background Silver tin oxide indium oxide belongs to novel environment-friendly silver-based electric contact materials and is widely applied to the fields of household appliances, industrial controls and automobile electric appliances. The silver tin oxide indium oxide electric contact material prepared by the internal oxidation process of the alloy has excellent arc erosion resistance, fusion welding resistance and material transfer resistance, so that the silver tin oxide indium oxide electric contact material is favored by electric contact material application manufacturers, but the silver tin oxide indium oxide prepared by the existing internal oxidation process of the alloy has the problems of overhigh hardness of the material and uneven metallographic structure distribution. The silver tin oxide indium oxide electric contact material prepared by the process has the problems of low conductivity, unstable contact resistance and the like, and the process can not solve the problem of silver-based bright zone on the surface of the alloy during the internal oxidation of silver tin indium oxide, and in addition, the process has higher requirements on equipment and higher investment. Comprehensive advantages and disadvantages are realized, and domestic manufacturers of silver-based electric contact materials do not apply the process to the field of internal oxidation of alloys. In addition, the silver-based bright band area on the surface of the silver-tin oxide indium oxide can be removed by adopting nitric acid solution, so that the silver-tin oxide indium oxide electric contact material without the silver-based bright band area is prepared. A small amount of experimentation is possible, but mass production is not desirable. Because silver, tin and indium are always bonded together under the action of high temperature in the oxidation process, the silver, tin and indium can not be completely dispersed after oxidation, when silver-based bright zone areas on the surface of the dispersed silver, tin and indium oxide are removed by adopting nitric acid solution, silver-based bright zone areas on the surface of the mutually bonded silver, tin and indium oxide are not completely removed, when silver-based bright zone areas on the surface of the bonded silver, tin and indium oxide are completely removed, silver-based bright zone areas on the surface of the dispersed silver, tin and indium oxide are removed by adopting nitric acid solution, silver-based in silver and indium oxide close to the silver-based bright zone areas are removed, and new oxide enrichment is generated. The result of the silver-based bright band removal by the nitric acid solution is that the silver-based bright band is not completely removed, so that the silver-based bright band still exists in the final finished product, or the silver-based bright band is removed, but new oxide enrichment is generated. Therefore, the method of removing silver-based bright band on the surface of the tin oxide-indium oxide by using nitric acid solution is not preferable. The silver tin oxide indium oxide electrical contact material has uneven metallographic structure distribution, influences the electrical performance of the material, such as instant adhesion, unreliable electrical service life and the like, and has high hardness, influences the processing performance of the material, such as wire drawing and wire breakage, rivet manufacturing and cracking and the like. The silver tin oxide indium oxide prepared based on the existing internal oxidation process of the alloy has the problems of overhigh hardness of the material and uneven metallographic structure distribution. For silver-based electric contact material technicians, how to develop an alloy internal silver oxide tin oxide indium oxide electric contact material with moderate hardness and uniform metallographic structure distribution is a problem which needs to be solved in the technical field of silver-based electric contact materials. Disclosure of Invention In order to solve the problems of overhigh hardness and uneven metallographic structure distribution of the silver tin oxide indium oxide prepared by the existing alloy internal oxidation process, the application provides a method for preparing the silver tin oxide indium oxide by constant-temperature and constant-pressure internal oxidation and wire grain recombination molding and an electric contact material prepared by