Structure Property Correlation of Al Based MMC Reinforced with Cu Coated Rice Husk Ash SiO2 Particles

Abstract

Metal coated reinforcements in metal matrix composites are advancing in the field of engineering to produce high quality composites by liquid metallurgy route due to improvement of wettability between reinforcement and matrix. In the present study, a comparative analysis of mechanical properties was carried out on Al based composite (with varying wt% of Mg) reinforced with uncoated and Cu coated RHA (rice husk ash) SiO2 particles. Tensile testing results of the composites indicate that UTS and YS of the composites reinforced with Cu coated SiO2 particles was significantly higher than uncoated particles. The Cu coated SiO2 particles act as a protrusion over the matrix carrying the major portion of the applied tensile load and thus composites are protected from failure. When Mg reaches 1.5 wt%, wettability of matrix with reinforcement is maximum, leading to the formation of hard compounds such as CuO, CuAlO2 and Al2CuMg at interface. This enhances interfacial bonding strength as well as load transfer from matrix to reinforcement, which leads to higher tensile strength along with ductility.