Research on the influence of rolling deformation on the properties of coated graphene/copper composite flat wire

This study employed a coating process to fabricate graphene/copper (Gr/Cu) composite flat wires. The microstructure of the graphene coating was regulated by introducing shear stress and compressive stress through rolling deformation. A systematic comparative analysis was conducted on the texture characteristics of the copper flat wire matrix, the morphology evolution of the graphene coating, and the microstructural characteristics of the coating‒copper matrix interface before and after rolling deformation. The results indicate that the graphene coating exhibits significant macroscopic defects, such as agglomeration and pores, leading to low carrier transport efficiency. When the rolling deformation does not exceed 20%, both the electrical conductivity and mechanical performance of the Gr/Cu composite flat wire tend to increase with increasing deformation. The graphene dispersibility and coating density are significantly improved, and the graphene sheets become oriented along the rolling direction, providing a more favorable path for carrier migration. Concurrently, the copper matrix texture undergoes a distinct transformation, enhancing the tensile strength through a dislocation strengthening mechanism. However, excessive rolling deformation adversely affects the overall material performance. This study elucidates the role of rolling deformation in regulating the microstructure and properties of Gr/Cu composite flat wires, providing a reference for the development of high-performance Gr/Cu composite wires.