Studies Preparation And Properties Of SiC Particles Reinforced Aluminum Matrix Composites

Since particles reinforced AI matrix composites show superior properties such as high strength at high temperatures, wear resistance, high specific rigidity and easy to process, they are paid more and more attention by the industry. Silicon carbide particle is a kind of high performance non-metallic oxide ceramic material, which has the advantages of high rigidity and wear-resistance, high temperature resistance and low cost, it is widely used as reinforced particles to produce metallic composites.In this work, silicon carbide particles reinforced Al-alloy-matrix composites were prepared by powder metallurgy. The samples have better density. The mechanical properties of the composites reinforced by different volume fractions of silicon carbide particles were studied by choosing proper technique parameters. The technology of copper plating to silicon carbide particle surfaces was optimized to obtain a solution solving the compatibility between silicon carbide particles and matrix. The mechanical properties, density and wear behavior of the composites were also discussed.The experiments show that the copper coating on the surface of the silicon carbide particles can improve the interface bounding between the particles and the matrix if proper plating technology was used. The hardness and tensile strength increased first then decreased as sintering temperature increased, and the optimum sintering temperature is 570℃. As the volume fraction of the reinforced particles increased, the compactness of composites decreased, and the hardness and tensile strength of the composites increased first and then decreased. EDS analysis showed the reinforced particles evenly distributed in the composites.The dominant wear mechanism of the aluminum alloy is plastic deformation, but the wear mechanisms of the composites are mainly adhesion and slight scuffing. With the increase of the volume fractions of silicon carbide particles the abrasive wear takes more important role, which results in a higher wear resistance of the composites. The wear resistance of the copper coated silicon carbide reinforced Al matrix composites is much higher than that of uncoated particles reinforced composites.