Effect of preparing method of ZnO powders on electrical arc erosion behavior of Ag/ZnO electrical contact material

Two kinds of Ag/ZnO electrical contact materials were fabricated by powder metallurgy method. The electrical life testing was done to investigate the arc erosion behavior of the prepared contact materials. Their properties and morphologies were characterized and discussed in detail. Results showed that Ag/ZnO(c) with coprecipitated ZnO as the second phase had better mechanical and electrical properties compared with Ag/ZnO(a) with ZnO purchased from Aladdin Industrial, Inc. Besides, some typical morphologies, such as holes, Ag or ZnO enrichment zone, Ag skeletons and bubbling area, occurred on the surface of the contacts. Especially for Ag/ZnO(c), vertically aligned ZnO nanorod arrays were detected after the life testing without any other supporting equipment. The existence of a solid solution Zn1−x Ag x O and different energy generated during arcing process were possible reasons resulting in this phenomenon. A solid–vapor–solid mechanism was put forward to analyze the phenomenon mentioned above. These evidences could also offer some valuable information desired for reducing the splashing of Ag droplet under arcing.