Effects of Hot Extrusion, Load, Sliding and Velocity on the Wear Properties of ZrO2@CNTs/2A70 Composites

In this work, the microstructure, mechanical, and tribological properties of as-cast 2A70, as-cast ZrO 2 @CNTs/2A70 composites, as-extruded 2A70 and as-extruded ZrO 2 @CNTs/2A70 composites were investigated. The as-cast ZrO 2 @CNTs/2A70 composites were prepared by pre-dispersing ZrO 2 @CNTs using ball milling and applying ultrasonic vibrations during melt casting. The morphology and distribution of the second phase were improved by hot extrusion and the distribution of ZrO 2 @CNTs was observed under SEM by deep corrosion. The mechanical properties of the materials were examined. Further, the dry sliding tribological properties were evaluated at different loads (20N, 40N, and 60N) and sliding speeds (0.19 m/s and 0.57 m/s). The results show that ZrO 2 @CNT was uniformly distributed in the composites after extrusion. As-extruded ZrO 2 @CNTs/2A70 composites had the highest ultimate compressive strength, but lower elongation than as-extruded 2A70. The increase in load and sliding velocity led to a change in the wear state, which had a significant effect on the wear rate.