Studies on properties of as-cast Al6061-WC-Gr hybrid MMCs

Abstract

Aluminum (Al) alloys started replacing cast iron and bronze alloys in the manufacture of wear-resistant parts and are materials of interest owing to their low density, higher strength to weight ratio, which is an additional advantage in aerospace, marine and automotive applications. Al-metal matrix composite (MMC) materials are very much popular due to the reason that these composites possess good mechanical properties and higher wear resistance. This article is aimed to present the experimental results of microstructure, hardness, tensile, yield and compression strength, percentagage elongation, volumetric wear loss, and wear rate of Al6061-Tungsten Carbide (WC)–Graphite (Gr) reinforced hybrid MMCs. The composites were prepared using the liquid metallurgy technique, in which 0 to 4 wt% of WC particulates were dispersed into the matrix alloy in steps of 1 wt% by maintaining the Gr to 4 wt% constant. The experimental results indicate that the density of the hybrid-MMCs increases with increased WC content and further, agree to the values obtained through the rule of mixtures. The physical, mechanical and the tribological properties of the Al6061-WC-Gr hybrid MMCs were found to increase with increased WC content in the matrix at the cost of reduced ductility. The WC and Gr reinforcements contributed significantly in improving the wear resistance of Al6061-WC-Gr hybrid MMCs.