First-principles and experimental investigations on physical properties and arc erosion behavior of metal-doped AgSnO2 electrical contact materials

The effects of metal doping on the structural and physical properties of AgSnO2 contactors were investigated using simulations and experiments based on first-principles calculations. The electrical contact test system was tested for 20,000 electrical contacts to check the physical properties under 24 V/15 A DC resistive load and analyze the relationship between the parameters. The erosion morphology of the contact material was characterized by a 3D surface profilometer, and the mechanism of the molten pool force, material transfer, and arc erosion behavior was studied in detail. The results show that metal doping can improve the thermal stability, mechanical properties and electrical conductivity of the materials, and significantly affect the crystalline and electronic structure of the materials, resulting in better stability and resistance to arc erosion. The best arc erosion performance of AgSnO2-Y is related to its superior thermal stability and electrical properties, while the better arc erosion performance of AgSnO2-Cu is probably related to its good mechanical properties. In addition, metal doping has a significant effect on the arc formation and interruption of AgSnO2 contactors and leads to a change in the material transfer mode. This study provides a feasible method for the analysis of metal doping to improve the erosion performance of contact materials and provides a valuable reference for the further development of research on arc erosion resistance of contactors.