Investigation of microstructure, mechanical, and tribological properties of MoSi2-reinforced copper-graphene composites

Abstract

The MoSi2-reinforced copper-graphene composites (Cu-MoSi2-GNS) were prepared using mechanical ball milling and spark plasma sintering techniques. The effects of MoSi2 content on the microstructure, electrical conductivity, mechanical performance, and tribological properties were systematically investigated. Results indicate that the addition of MoSi2 significantly enhanced strength and hardness, although slightly reducing electrical conductivity. When the MoSi2 content does not exceed 5 wt%, MoSi2 is uniformly dispersed, refining copper matrix grains and improving GNS dispersion. Optimal MoSi2 addition facilitates the formation of a stable subsurface structure with complete mechanical mixture layer, improving wear resistance and self-lubricating properties. The main wear mechanism shifts from adhesive to abrasive wear. At 5 wt% MoSi2, the Cu-MoSi2-GNS composites exhibits superior mechanical properties, electrical conductivity, and tribological performance.