Preparation and properties of graphene reinforced Cu/0.5CeO(2)30Cr electrical contact materials

A graphene reinforced Cu/CeO2Cr electrical contact material with high strength and electrical conductivity was designed. Graphene oxide (GO) was prepared with modified Hummers' method. Composite powders of GO, ceria nanoparticles, copper and chromium were prepared by freeze-drying. The GO-Cu/0.5CeO(2)30Cr electrical contact material was prepared by spark plasma sintering. Raman and X-ray photoelectron spectroscopy (XPS) characterization results indicated that during the sintering process, the graphene oxide was transformed into reduced graphene oxide (RGO). In addition, SEM and TEM characterization results indicated that the CeO2 nanoparticles were uniformly dispersed in the matrix, which hindered the movement of dislocations and improved the strength of the matrix, and a small amount of carbon atoms combined with Cr to form Cr3C2, enhancing the interface bonding. Compared with Cu/0.5CeO(2)30Cr composites, the electrical conductivity, hardness, tensile strength, and welding resistance of the two composites containing 0.5 wt% and 1.0 wt% GO were both improved and the 0.5GO-Cu/0.5CeO(2)30Cr composites have better welding resistance.