Study On The Influence Of Thermal Processing On The Preparation Process And Properties Of Graphene Reinforced Copper-based Composite

Copper has been used for thousands of years as one of the earliest traditional metal materials.However,it is limited by its low hardness and strength in the industrial field.In order to meet the practical application needs and solve the problem of high strength and conductivity of copper-based materials,copper matrix composites emerge at the right moment.By introducing an ideal reinforcer,graphene,into the copper matrix,the researchers have successfully prepared the high conductivity and strength composites.At present,graphene reinforced copper matrix composites face two major problems: in the one hand,due to the thermal expansion coefficient of carbon material can’t match the coppers’,strong binding force cannot be formed at the interface.In the other hand,how to achieve uniform distribution of graphene in the copper matrix to avoid the problem of graphene layer agglomeration is still hard problem.In order To cope with the above two problems,this paper adopts chemical vapor deposition method to prepare graphene/copper matrix composites to achieve uniform dispersion of graphene in copper matrix.Then,the densities of the composites were further improved by hot-rolling and hot-pressing processes to enhance the overall performance of the materials.The number of graphene layers grown on the copper matrix and the structural integrity of graphene have a significant effect on the physical properties of graphene/copper composites.To control this parameter,the bulk porous copper matrix was prefabricated by a powder compactor and coated with graphene films on the surface of the copper matrix by chemical vapor deposition in this experiment.After the composites were prepared and treated,high conductivity and high strength composites were obtained.The effects of parameters such as hydrogen gas flow rate,acetylene gas flow rate,hot pressing time,hot pressing temperature,hot rolling temperature and down rolling amount on the comprehensive performance of the composites were discussed during the preparation of graphene/copper matrix composites.The results show that the uniform dispersion of graphene in the copper matrix was effectively achieved by chemical vapor deposition.The appropriate hot rolling and hot pressing processes can greatly improve the densities of the composites and enhance their comprehensive performance.The tensile strength of the final composite can reach 263 MPa,which is 22.3% higher than that of pure copper,and the hardness can reach 109 HV,which is 29.7% higher than that of pure copper,and the wear amount is 60% lower than that of pure copper,and the electrical conductivity of107.5% IACS is slightly higher than that of pure copper.