| SiC particles reinforced Al matrix composite is one of advanced metal matrix composites (MMC), having widespread prospect of applications. Since its excellent strength at high temperatures, good wear resistance, high specific modulus and easy processing, the composite has been used as structure material in aerospace, automobile and other industries. Recently, it was found that the composite with high volume fraction of SiC particles could be used in semiconductor and electronic industry due to its high thermal conductivity and low thermal expansion coefficient.In this thesis, Composites made with Al-Cu-Mg alloys and Sic particles were prepared by powder metallurgy technology and mechanical alloying(MA). The microstructure and property of the powders were investigated at different period of MA processing. The result showed that the SiC particles can be embedded in the matrix and uniform distribution in matrix by the MA.The mechanical properties of the Al matrix composites in different volume fraction of reinforced materials or weight fraction of Mg were studied. The sinter and heat treatment techniques were optimized by the XRD and SEM. The main results show:1. With the increase of the volume fraction of Sic particles, the density of materials drops. The hardness and tensile strength of the materials increases and then decreases.2. With the increase of weight fraction of Mg, before the heat treatment the density of material, hardness and tensile strength change a little. After the heat treatment, the hardness and tensile strength increase and then decreased.3. The material density, hardness, tensile strength was noticeably improved by mechanical alloying .4. The optimum sinter techniques : the alloy powder made 0.8wt%Mg and 9Vol%SiC mill 4h by 150rpm, press 30 minutes at 390MPa, sinter 2h at 550℃, the natural heat treatment two days. The tensile strength of materials will increase by three times than the matrix by this way.
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