Effect of mechanical ball grinding time on the properties and microstructure of graphite-copper composite

Abstract In this paper, the graphite-copper composite was prepared by powder metallurgy sintering method which used copper powder and graphene powder as raw materials. The powders were mixed by ultrasonic dispersion and mechanical ball grinding method. The effect of mechanical ball grinding time on the properties and microstructure of graphite-copper composite was investigated using Optical microscope, scanning electron microscope (SEM) and Vickers hardness meter. The result showed that the distribution of graphite in the copper matrix was uniformly and formed a good interface by using the ultrasonic dispersion and mechanical ball grinding method. When the mechanical ball grinding time was raised from 2 hours to 16 hours, the relative density and Vickers hardness of the graphite-copper composite reached their maximum value, the relative density was 92.1%, the Vickers hardness (HV0.5) was 61.9HV. However, the properties of graphite-copper composite showed a downward or stabilize trend the mechanical ball grinding time increasing from 16 hours to 48 hours.