| The long-term preferred silver cadmium oxide (AgCdO) contact material in electrical and electronic equipments has been in many countries and regions expelled from both its production and application owing to concerns regrding the inherent toxicity of cadmium (Cd). It is thus strongly desirable to search novel environmentally friendly candidate materials of which the AgSnO2 family is believed to the first choice. Based on the further development of high energy ball milling(HEBM) technology, a systematic investigation was made in this paper on the influence upon the physical and mechanical properties of AgSnO2 of the metal oxide additives including Bi2O3, Co2O3, Cr2O3, CuO and Sb2O3 the addition of which is expected to improve the performance of the matrix material. Moreover, by employing a self-made testing systerm and other analysis facilities to find how the doping components effecting the dynamic properties of AgSnO2 was another research focus.Results indicated that HEBM was greatly responsible to the fine and uniform microstructures of AgSnO2 contact materials by reducing the size of both silver and tin oxide particals. The used additives in this paper were all beneficial to the better wettability between silver and tin oxide powders and accordingly contributed to the improvement of both mechanical and phycial properties of AgSnO2. Besides, the optimal content of all those dopants was found to be 0.5(wt%); After 100000 cycles under the current load, Bi2O3, Co2O3 and Cr2O3 were all validated to be effective in decreasing arc erosion area and material transfer and the sequence in their efficiency can be described as Cr2O3 > Co2O3 > Bi2O3 and Cr2O3 > Bi2O3 > Co2O3, respectively. Co2O3 can play an important role in partially preventing the over-temperature behavior and Cr2O3 was helpful in changing centralized arc to the extended one. AgSnO2-Bi2O3 and AgSnO2-Co2O3 are promising candidate contact materials with low and high current load, respectively.
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