Fabrication of Three-Dimensional Graphene/Cu-Ag Composites by In Situ Chemical Vapor Deposition and Their Properties

High-quality several-layer graphene film was fabricated on Cu-Ag alloy powder by in situ CVD at 900 °C, and three-dimensional graphene/copper-silver composites (Cu-Ag/G) were fabricated by spark plasma sintering (SPS). The analysis of XRD and EDS shows that the Ag element is uniformly dissolved in the matrix. The results of SEM, TEM and RAMAN show that several-layer graphene film was prepared in situ on the alloy substrate at atemperature as low as 900 °C has high quality and tightly wrapped around the matrix. The performance tests show that the tensile strength of Cu-Ag/G composites is 342 MPa, which is 23.5 and 33.1% higher than that of the unreinforced Cu-Ag (277 MPa) and Cu/G (257 MPa), respectively. The coefficient of friction of Cu-Ag/G composites is 0.23, which is 51 and 30% lower than Cu-Ag (0.47) and Cu/G (0.33), respectively. The corrosion potential of Cu-Ag/G composites shifted towards more positive values, and the corrosion current density decreased significantly. The corrosion inhibition efficiency of Cu-Ag/G reaches 74.70% which is stronger than Cu/G (45.39%), and the corrosion rate is 0.236 mm/year. The successful fabrication of Cu-Ag/G composites with excellent comprehensive properties provides a new way to further improve the performance of graphene/copper composites.