Influence of Fe and Al2O3 Addition on the Mechanical and Tribological Properties of Cu-Based Composites

In this study, Cu-based friction materials were prepared using a powder metallurgy process. Effects of the addition of Fe and Al2O3 in the Cu matrix on mechanical properties of the composite materials were studied. Tribological properties of the composites were investigated using a ball-on-disk contact friction tester. Investigation of microstructure and worn surfaces of the samples showed that the matrix of the prepared material could be effectively reinforced by the addition of Fe and Al2O3, which led to enhancement of composite hardness and strength. The Fe addition enhanced the friction coefficient and decreased the wear loss of the friction materials, while the Al2O3 addition could further improve these properties. The outstanding properties were attributed to dispersion-strengthening owing to the presence of Al2O3 in the matrix. The wear behaviors and mechanisms of Fe and Al2O3 in Cu-based friction materials had been discussed. Deformation and grooves were present on the worn surfaces, indicating that the wear mechanism of the samples was dominated by adhesion and abrasive wear. The worn surface of the composite with Al2O3 was relatively compact in comparison to other samples. These observations indicated that the addition of Al2O3 together with Fe could stabilize the friction and wear properties of the Cu-based friction composites.