In-situ grown continuous graphene network enhances the electrical conductivity and tribological properties of copper matrix composites

Abstract

Copper has good electrical conductivity but poor mechanical and wear-resistant properties. To enhance the mechanical and wear-resistant properties of the copper matrix, a strategy of in-situ generation of graphene was adopted. Through ball-milling processes, a carbon source and submicron spherical copper were uniformly dispersed in a dendritic copper. Then, a uniform and continuous graphene network was generated in-situ in the copper matrix during the vacuum hot-pressing sintering process to improve the performance of composites. The graphene product exhibited lubrication effect and provided channels for electrons to move through the interface, improving the wear resistance and the electrical conductivity of composites. When the graphene content in the composite material was 0.100 wt.%, the friction coefficient and the wear rate were 0.36 and 6.36 × 10⁻⁶ mm³·N⁻¹·m⁻¹, diminished by 52% and reduced 5.11 times those of pure copper, respectively, while the electrical conductivity rose to 94.57% IACS and the hardness was enhanced by 47.8%. Therefore, this method provides a new approach for the preparation of highly conductive and wear-resistant copper matrix composite materials.