Effect of Cr@RGO structure on microstructure and properties of RGO/CuCr25 composite

Abstract

CuCr alloy with high Cr content (20–50 wt.%) is the main contact material for medium voltage and high current vacuum interrupters. However, the influence of network distribution of Cr particles affect the conductivity of CuCr alloy, and its properties strongly depend on the size of Cr particles. In this paper, Cr@RGO (Cr powder coated with reduced GO) was prepared by BSA (bovine serum protein) electrostatic assembly method, and then RGO/CuCr composites with different graphene content were prepared by vacuum hot pressing sintering process. The results show that the size of Cr particles decreases with the increase of graphene content and the network of Cr particles became fractured. When the content of RGO is 3.0 wt.%, the size of Cr phase is 19.9 μm, which is 23.8% less than that of CuCr25 of 26.1 μm. The Brinell hardness and electrical conductivity of 3.0 wt.% RGO/CuCr composite are 102.5 HB and 52.9% IACS, which is increased by 8% and 6% in contrast with that of CuCr25. And the Preparation of RGO/CuCr is simple, feasible, replicable and easy to achieve the goal of the industrial preparation.