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There have been numerous studies in the literature investigating various aspects of the AA6063 metal matrix composites. The studies generally concentrated on how the ceramic particles (SiC) affect the mechanical and thermal properties of the PMMCs which are usually aluminum based (especially AA6063). Experiments conducted with Al and Mg alloys showed that addition of ceramic particles considerably increases the tensile strength of the alloy (Ding, Liew & Liu, 2005; Quan Yanming & Bangyan, 2003; Hung, Loh, & Xu, 1996). McDanels (1985), Yang, Cady, Hu, Zok, Mehrabian, and Evans (1990), Doel and Bowen (1996) showed that fine SiC particles with 10 µm particle diameter yield higher fracture toughness and strength than those with coarse particles. The uniform distribution of particles in the final product is essential in the PMMCs to obtain desired mechanical and thermal properties. However, investigations showed that there is usually particle clustering or agglomeration occurs in such composites. This clustering significantly decreases the local property of the PMMC. Lloyd, lagace, Mcleod, and Morris (1989) indicated that damage in the composite initiates at the particle-clustered regions. Clyne and Withers (1993) proposed that the behavior of a single particle in the clustered region depends on the cluster size, volume fraction of particles and arrangement of particles in the cluster. Prangnell, Barnes, Roberts, and Withers (1996) experimentally and theoretically showed that during compressive deformation of aluminum alloy reinforced with SiC particles, damage formation is concentrated at particle-clustered regions. The particle fracture and void form at particle interface depending on the particle size. The particle with larger size may crack under stresses leading to higher void fraction in the system. The distribution of reinforcement materials (SiC), one of the problems encountered in metal matrix composite processing is the settling of the reinforcement particles during melt holding or during casting. This arises as a result of density differences between the reinforcement particles and the matrix alloy melt. The reinforcement distribution is influenced during several stages including (a) distribution in the liquid as a result of mixing, (b) distribution in the liquid after mixing, but before solidification, and (c) redistribution as a result of solidification.