Enhancing Arc Erosion Resistance of Agni Contact Material by a Three-Dimensional Graphene Network

Abstract

The three-dimensional graphene (3D-Gr) reinforced Ag-10wt.%Ni contact material was fabricated by in-situ growth of Gr on Ni powders followed by powder metallurgy in this work. The electrical contact tests were performed on an electrical contact test system. The microstructure and eroded morphologies were characterized, the effect of the 3D-Gr on the physical, mechanical and electrical properties of the Ag-10wt.%Ni@Gr contact material was investigated, and the arc erosion mechanism was discussed as well. The results demonstrate that the incorporation of 3D-Gr enhances the electrical conductivity, hardness and arc erosion resistance. As compared to Ag-10wt.%Ni contact material, the electrical conductivity and hardness of the Ag-10wt.%Ni@Gr contact material are respectively increased by 7.2% and 10.9%. Moreover, Ag-10wt.%Ni@Gr contact material exhibits lower arc energy, shorter arc duration and less mass loss. The superior arc erosion resistance of the Ag-10wt.%Ni@Gr contact material can be attributed to the formation of three-dimensional graphene, which provides a continuous heat-transferred pathway, mitigates the oxidation of Ni and reduces the splashing of molten pool.

Keywords: AgNi contact material, Three-dimensional graphene, Electrical conductivity, Arc energy, Arc erosion