Abstract:Al-5%Si-Al₂O₃ composites were prepared by powdermetallurgy and in-situ reactive synthesistechnology. Friction and wear properties of Al-5%Si-Al₂O₃ composites were studied using an M-2000 wear tester. The effects of load, sliding speed and long time continuous friction on friction and wear properties of Al-5%Si-Al₂O₃ composites were investigated, respectively. Wear surface and wear mechanism of Al-5%Si-Al₂O₃ composites were studied by Quanta 200 FE-SEM. Results showed that with load increasing, wear loss and coefficient of friction increased. With sliding speed going up, the surface temperature of sample made the rate of the producing of oxidation layer increase, while wear loss and coefficient of friction decreased. With the sliding distance increasing, coefficient of friction increased because the adhesive wear mechanism occurred in the initial stage, then formation and destruction of the oxide layer on the surface of the sample tended to a dynamic equilibrium, the surface state of the sample was relatively stable and so did the coefficient of friction. The experiment shows that the main wear mechanism of Al-5%Si-Al₂O₃ composites includes abrasive wear, adhesive wear and oxidation wear.

Key words: Al-5%Si-Al₂O₃ composites; friction and wear; coefficient of friction; load; sliding speed