Effect of heat-treatment on friction and wear properties of Al2O3 and carbon short fibres reinforced AlSi12CuMgNi hybrid composites

Al2O3 and carbon short fibres reinforced AlSi12CuMgNi metal matrix hybrid composites were fabricated by preform squeeze-infiltrated route. The fibres distribution and microstructure of matrix in the hybrid composites were observed. Moreover, the effect of heat-treatment on the dry sliding friction and wear properties of the hybrid composites were determined by statistics method under the condition of 196 N load and velocity of 0.837 m/s. Alumina and carbon short fibres distributed hybrid uniformly in the hybrid composites. Metal matrix microstructure was fined after heat-treatment. The results of statistics analysis showed that four samples of wear rate and friction coefficient of both as-cast and as heat-treated hybrid composites accorded with normal distribution. The statistics average values of wear rate and friction coefficient of as-cast hybrid composites were larger than those of as heat-treated hybrid composites. Heat-treatment was beneficial to the improvement of dry sliding friction and wear property of the composites. Dominant wear mechanism of as-cast hybrid composites was ploughing grooves and delamination. Heat-treatment contributed to improving the resistivity of delamination of composites. Dominant wear mechanism of as heat-treated hybrid composites was slightly ploughing.