The combination of rolling-and-T6-treatments with Al 2 O 3 -reinforcing-particles effect on A6061 metal-matrix composites

Al–Si alloys, with excellent properties such as low weight, low thermal expansion coefficient, and high wear-resistance, are ideal materials for the automobile and aerospace industries. However, their applications have been hampered by the coarsening of the primary-Si particles in Al–Si alloys. In this study, the rolling-and-T6-treatments effect on A6061/Al₂O₃ metal-matrix composites is investigated. The A6061/Al₂O₃ metal-matrix composites with different amounts of reinforcing Al₂O₃ particles are examined in the aspects of wear resistance and hardness. Upon the T6 treatment, the hardness is enhanced in all cases and is summarized. The results suggest that the increase of Al₂O₃ particles reduce the wear rate. The possible reinforce mechanisms and the environmental temperature effects are discussed. This improvement in wear resistance is due to the particle size refinement of silicon at a high percentage-roll-reduction.