Fabrication of Cu Surface Composite Reinforced by Ni Particles Via Friction Stir Processing: Microstructure and Tribology Behaviors

In the present investigation, friction stir processing (FSP) was used to integrate Ni particles into the surface of copper in order to fabricate a surface composite. Determining an optimized percentage of Ni particles, different dimensions of grooves were machined into the Cu plates. Then, the specimens' grooves were filled by nickel reinforcement particles, and friction stir process was performed on the specimens with tool rotation speed of 800 rpm and traverse speed of 50 mm/min. Optical microscope (OM) and scanning electron microscope (SEM) were used to evaluate the microstructure. Pin-on-disk test was performed to evaluate wear properties using pins manufactured from the FSPed zone. Also, Micromet-Buehler Vickers hardness tester was used to test the FSPed surfaces' microhardness. The results show that the best properties are obtained when using 2 × 2 mm groove. In this situation, microhardness and wear properties were improved as 40% and 60% compared to the substrate, respectively.