Synthesis and comparative sliding wear behavior of stir cast Mg and Mg/Al2O3 metal matrix composites

The demand of light weight materials with better characteristics are growing day by day due to their demand in automobile and aerospace industry. Magnesium matrix composites have been developed as excellent materials in comparison to conventional cast materials. In the current study, magnesium-based composites have been successfully prepared using automatically controlled stir casting setup. Al2O3 particles were embedded in pure Mg matrix by varying the weight % from 3-12. Hardness testing was done on as cast samples. Wear tests were conducted on pin-on-disk under different loads conditions (1 kg-5 kg) and fixed sliding velocity (1 m s(-1)). The hardness and wear resistance of as cast composites significantly improved in comparison to unreinforced magnesium and it further enhanced with the increase of reinforcement content upto 9 wt% but decreased with further addition. The enhancement in hardness and wear performance was attributed to the dispersion hardening owing to the addition of hard reinforced particles. It was observed that wear resistance decreased with the acceleration of applied load. The dominating wear mechanisms such as abrasion and oxidation were seen in as cast composites.