Study of metal–ceramic WC/Cu nano-wear behavior and strengthening mechanism

Abstract

In view of the inherent poor tribological properties of copper, the reinforcement of copper matrix composites with WC particles presents a promising research area with significant industrial influence. Therefore, in the present study, a molecular dynamics approach is used to simulate the process of repeated friction of diamond grinding balls on WC/Cu composites, and the friction force, friction coefficient, abrasion depth, wear rate, abrasion morphology, von-Mises stress, internal defects, workpiece energy, and performance comparison of different layer thicknesses are systematically investigated in the multiple friction process. It is found that the fluctuation amplitude of friction force, friction coefficient, and abrasion depth are smaller and the fluctuation frequency is larger during the initial friction, whereas near the WC phase, there appears extreme values of the above parameters and the von-Mises stress is highly concentrated while the workpiece energy contonues to increase. In the case of the repeated friction, with the increase of friction times, the friction force, friction coefficient, and abrasion depth fluctuation amplitude increase, the fluctuation frequency decreases, the workpiece energy reaches an extreme value near the WC phase, and a large number of dislocations plug, therefore, the region is strengthened. As the distance between the grinding ball and the WC phase decreases, the more obvious the strengthening effect, the stronger the ability of workpiece to resist the wear will be.