Cu-nano Al <sub> 2 </ Sub> O <sub> 3 </ Sub> Composite Powders Prepared By Wet Sintered Microstructure And Properties,

In this paper, nanosized Al2O3 ceramic particles were chose as reinforcing phase. Enhanced with ultrasonic wave the particles were covered with copper using method by electroless plating, the Copper-matrix composite was developed by hot-press sintering process of the composite powder. The composition, microstructure , hardness , density and dry sliding wear property of the new material have been studied.The composite powder was analysed by using XRD, TEM. The result showed that there were two phases: ? -A12O3 and copper, the particles were covered with copper, the bond of A12O3 particle with copper phase was good.The composition, microstructurex hardness and density were analysed. It was found that nanosized A12O3 ceramic particles were evenly dispersed in the copper matrix. The composite hardness was increased comparing to copper due to the reinforcement effect of nanosized Al2O3. And the density was related with the parameters of hot-press sintering processing.The dry sliding wear of the composites was investigated in a pin-on-disk wear test rig. The wear behavior and the morphology of worn surface of samples were analysed. The result showed that Cu-(Al2O3)n composite was excellent at wear resistance. The wear rate increased with the increase of load, and it decreased with the increase of the nanosized Al2O3 content. The parameters of hot-press sintering process, the temperature and the pressure, affected the wear resistance of Cu-(Al2O3)n composite, that is, the high temperature and the high pressure had increased the wear resistance of Cu-(Al2O3)n composite. And the wear resistance of Cu-(Al2O3)n composite was related to the cold-press pressure before the hot-press sintering process. The influence of hot-press pressure on the wear resistance was more significant than that of the cold press process.