Characterization of Stir Cast Al—Cu—(fly ash + SiC) Hybrid Metal Matrix Composites

Abstract

Metal matrix composites are engineered materials with a combination of two or more dissimilar materials, (at least one of which is a metal) to obtain enhanced properties. In the present investigation Al-4.5% Cu alloy was used as the matrix and fly ash and silicon carbide (SiC) as reinforcements. The hybrid metal matrix composite was produced using conventional foundry techniques. The fly ash and SiC were added in 5%, 10%, and 15% by weight (equal proportion) to the molten metal. The hybrid composite was tested for fluidity, hardness, density, mechanical properties, impact strength, dry sliding wear, slurry erosive wear, and corrosion. The microstructure examination was done using scanning electron microscope to assess the distribution of particulates in the aluminum matrix. The results show that there is an increase in hardness with increase in the particulates content. The density decreases with increase in fly ash and SiC content. The tensile strength, compression strength, and impact strength increases with increase in fly ash and SiC. The resistances to dry wear and slurry erosive wear increases with increase in fly ash and SiC content. Corrosion increases with increase in fly ash and SiC content. This material can be used as bearing material.