Preparation and Wear Resistance of Aluminum Composites Reinforced with In Situ Formed TiO/Al₂O₃

An in situ TiO/Al₂O₃-reinforced Al composite is successfully prepared using a powder metallurgy route by the reaction of Ti₂CO and Al powder. The Ti₂CO powder is produced by carrying out a carbothermic reduction of titanium dioxide at 1000 °C. XRD results show that the final product is composed of Al, TiO, Al₂O₃, and Al₃Ti. Morphology examination of the composite reveals the presence of bigger blocks of TiO and fine particles of Al₂O₃ and the volume fraction of reinforcement is found to range between 18 and 55%. As the volume fraction of the reinforced materials approaches 50%, the particles start to agglomerate. Dry sliding wear tests conducted using a conventional pin-on-disk testing machine show that the wear resistance of the composite is higher than that of the pure aluminum ingot. The wear rate of the composite increases almost linearly with the increase in the wear distance. The sliding wear test shows that as the volume fraction of the reinforced phase increases, the coefficient of friction decreases. The wear mechanism is also discussed.