Effect of Graphene Electroless Copper Plating on Microstructure and Properties of Spark Plasma Sintering Graphene Reinforced Aluminum Matrix Composites

Copper-plated graphene powder was obtained by electroless plating, and then was mixed with aluminum powder by electrostatic self-assembly. The copper-plated graphene reinforced aluminum matrix composite was prepared by spark plasma sintering. The microstructure and properties of different mass fractions (0.1%,0.2%,0.3%,0.4%,0.5%) of copper-plated graphene reinforced aluminum matrix composites were investigated, and were compared with those of 0.1wt% uncopper-plated graphene reinforced aluminum matrix composite. The results show that the copper-plated graphene was uniformly dispersed in the composites, and the relative density of the composites was more than 99%. Aluminum reacted with copper to form the intermediate phase Al₂Cu, but no Al₄C₃ interfacial phase was formed. The hardness and wear resistance of the copper-plated graphene reinforced aluminum matrix composites were better than those of the uncopper-plated graphene reinforced aluminum matrix composites. With the increase of copper-plated graphene content, the hardness of the composites first increased and then decreased, and the wear mass loss and friction coefficient first decreased and then increased. When the mass fraction of copper-plated graphene was 0.2%, the composite had excellent comprehensive properties with hardness of 74.7 HV, and the smallest wear mass loss and friction coefficient of 0.002 3 g and 0.259, respectively, and the wear mechanism was oxidation wear.