Contrastive Research on Electrical Contact Performance for Contact Materials of Cu-SnO2 and Cu-ZnO2 Alloys

Abstract

Herein, SnO 2 -and ZnO 2 -doped (1.5 wt.%) composite Cu powder was prepared by mechanical alloying (MA) respectively, and both the contact materials of oxide-doped Cu alloys were subsequently obtained by canned hot-pressing powder sintering with hot extrusion combined. Scanning electron microscopy (SEM), laser scanning confocal microscopy (LSCM) and self-designed electrical breakdown device were used for investigating the microstructure and properties including electric conductivity and hardness, especially for electrical contact performance of the Cu-SnO 2 alloy and in compared with the Cu-ZnO 2 alloy. The experimental results show that the hardness of Cu-SnO 2 and Cu-ZnO 2 contact materials are 103.5±1 HV and 192.7±1 HV, respectively, which meet the hardness standard of national standard electrical contact materials. Meanwhile, the relative conductivity %IACS are 7.24% and 6.20%, respectively, which are higher than the traditional Cu-based contact materials. This electrical life simulation test system was designed independently, and the results indicate that the switching times of Cu-SnO 2 contact materials are much more than that of Cu-ZnO 2 . The addition of SnO 2 can effectively improve the arc extinguishing characteristics and the anti-welding performance of the contact materials is enhanced. In summary, SnO 2 -doped Cu-based contact materials possess excellent comprehensive properties, which can provide reference for potential applications in contact materials.