Effect of graphene on microstructure and tribological properties of FLG/SiC/TC4 composites prepared by vacuum arc melting

Ti-6Al-4V (TC4) alloy, characterized by low density, high tensile and fatigue strengths, and excellent corrosion resistance, is a vital material widely used in aerospace, chemical engineering, energy, and biomedicine. However, its poor strain-hardening effect and weak protective mechanically mixed layer (MML, a surface layer formed by mechanical actions with material mixing) limit its tribological applications. In this study, few-layer graphene (FLG)/SiC/TC4 composites were fabricated via vacuum arc melting, with SiC added to suppress the reaction between FLG and the matrix. The effects of FLG content on mechanical properties and wear resistance were investigated. Results show that moderate FLG addition promotes the formation of a continuous, dense MML during dry friction, protecting the matrix and lowering the wear rate. The composite with 0.4 wt% FLG shows excellent tensile strength and wear resistance, with its tensile strength increasing from 839.57 MPa of pure TC4–939.25 MPa, the depth of plastic deformation zone after wear becoming shallower, and the wear rate significantly decreasing by 52.15 %.