PROCESSING, MICROSTRUCTURE AND MECHANICAL PROPERTIES OF ALUMINUM BASED METAL MATRIX COMPOSITES

Abstract

In the present study, processing, microstructure and properties of Al-4.5Cu alloy and A1-4.5Cu/15wt%SiCp metal matrix composites were investigated. The microstructural characterization studies revealed a relatively uniformly dispersed distribution of SiC particulates and a good interfacial integrity between matrix and SiC particulates. Tensile test results revealed that SiC reinforcement did not dominantly help to improve the strength of composite samples by rheocasting process primarily due to the presence of porosity in composite samples. Wear tests at different applied normal loads and sliding speeds on Al-4.5Cu alloy and Al-4.5Cu/15wt%SiCp composites were carried out in the present study. Experimental results indicate that wear rate increases monotically with normal load (from 30N to 70N) at a sliding speed of 1 m/s and the composite samples exhibit different wear behavior compared to their monolithic counterparts under the range of sliding conditions tested in this investigation. Generally, the wear resistance of the composites is better than the unreinforced matrix alloy. The results also appear to suggest that composites with smaller particulate sizes would have a great influence on their wear behavior particularly at higher sliding speed.