Mechanical Behaviour of Mg/SiC Composite Processed by Friction Stir Processing

Abstract

Due to their good mechanical and physical properties as well as their low densities, Magnesium Matrix Composites are considered as an attractive option for different aerospace and other commercial applications. Lately, Friction Stir Processing (FSP) which is considered as an effective modification to Friction Stir Welding (FSW) has shown a great protentional as successful alternative for fabricating Metal Matrix Composite (MMC). One major difference between conventional engineering materials and MMC is the addition of reinforcing elements that results in an overall enhancement of the composite's stiffness and strength. This paper discusses the effect of using Silicon Carbide (SiC) reinforcement particles in AZ 31B magnesium alloy base composite using FSP. Effect of reinforcement particles on the thermal profile, microstructure, micro-hardness, tensile properties and impact toughness are discussed. In addition, the effects of tool rotational and translational speeds on the microstructure and micro-hardness of the Mg/SiC surface composite have been examined. Mg/SiC surface composite was successfully fabricated using FSP. Results suggest that Mg/SiC surface composite can be used to significantly enhance the micro-hardness and the ultimate tensile strength within the stir zone.