Study On Performance Improvement Mechanism Of The Silver Tin Oxide Contact Material

Because of its excellent switch characteristics, AgCdO, as a contact material, has been widely used in the production of low-voltage electric apparatus. Meanwhile the AgCdO material has disadvantage that cannot be ignored: the Cadmium Poisoning which appears during the manufacture and use of AgCdO. Therefore, the researches of new contact material are extensively regarded. Silver tin oxide is the most promising non-toxic material to substitute silver cadmium oxide. But AgSnO2 material has its fatal shortages: large contact resistance and high temperature rise. These two points seriously affect the electrical performance of low-voltage electric apparatus that adopt AgSnO2. The hige hardness of AgSnO2 makes the composite molding of it extremely difficult. So, it is a very important issue in contact materials research to solve the above key problems from the component design and manufacuture method.Based on the Natural Science Foundation of Hebei Province, Study on Performance Improvement Mechanism of the Silver Tin Oxide Contact Material (ID: 502048), the addition of rare earth oxides of silver tin oxide contact material is studied detailly in this paper. First, it is validated that the rare earth oxides is difficult to decompose and the bismuth oxide is wettable. Silver tin oxide contact material is prepared by chemical coprecipitation which is added rare earth oxides. The physical properties of the contact material are measured. The influence of technical parameters on performance is analysised. The microstructure of the material is analysised. And then, the electrical performance is tested by Electrical Contact Material Parameter Tester. Finally, The Ag/SnO2+ La2O3+ Bi2O3 material and AgCdO material are respectively assembled on the CJ20-40 alternating contactors. The temperature rise, make-break capacity and arc erosion have been tested.