Elevated Temperature Tribological Performance of Submicron Alumina Particle-Reinforced 6061 Aluminum Alloy Under Dry Conditions

Tribological behavior of aluminum (Al) 6061 alloy reinforced with 20% submicron (0.7 μm) alumina (Al₂O₃) particles was evaluated under dry conditions at temperatures ranging from 25 to 300 °C. Pin-on-disk wear tests were performed with the composite pin sliding against AISI 4041 steel counterface disk at selected loads. Under dry conditions, the wear resistance of the composite was characterized by two regimes, namely, mild and severe wear at all temperatures. However, the critical load for severe wear was found to decrease with increase in temperature, indicating decrease in wear resistance with increase in temperature. The worn surfaces were characterized by abrasion, delamination, and adhesion in mild, transition, and severe wear regions, respectively, at room temperature. However, at elevated temperatures, matrix softening of the composite was found to be dominant mechanism of wear in addition to particulate fracture.