Wear Characteristics of Al7075/Al<sub>2</sub>O<sub>3</sub>/SiC Hybrid Metal Matrix Nano Composites

Abstract

In the present investigation Aluminum matrix composites (AMMCs), Al7075 Alloy as matrix metal and Al2O3/SiC particles (2-8%) with an average particulate size of 20, 50 nm as strengthened material have been processed by the stir casting method. For the counter surface wear testing, a computerized pin on a wear tester was used as EN31 (58-60 HRC) steel disc and composite pin. The wear rate for the matrix metal and composites in terms of weight loss per unit sliding distance, friction coefficient, and volume loss were achieved. The composite results show better resistance to wear than matrix metal. SEM was used to investigate the microstructural characterization of worn surfaces. Sample weight loss was calculated and the change in cumulative wear loss at a sliding distance was uniform both for metal matrix as well as for composites. The wear speed for composites was also noted to be small compared to the metal matrix. In addition, experiments have shown that, with the increasing weight fraction of Al2O3/SiC and the coefficient of friction increases with increasing sliding velocity and weight fraction of Al2O3/SiC, the wear rate reduces. The wear characteristics (wear rate, coefficient of friction and wear loss) were better than those of other composites and the matrix metal with 6wt% Al2O3/SiC composites.