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Copper-matrix composites reinforced with SiC particles are prepared by mechanical alloying. The microstructure characteristics, relative density, hardness, tensile strength, electrical conductivity, thermal conductivity and wear properties of the composites are investigated in this paper. The results indicate that the relative density, macro-hardness and mechanical properties of composites are improved by modifying the surface of SiC particles with Cu and Ni. The electrical conductivity and thermal conductivity of composites, however, are not obviously improved. For a given volume fraction of SiC, the Cu/SiC_(Ni) has higher mechanical properties than Cu/SiC_(Cu). The wear resistance of the composites are improved by the addition of SiC. The composites with optimized interface have lower wear rate.

Taking the high volume fraction SiCp/6061Al-based composite material prepared by the powder metallurgy method under different sintering temperatures and holding times as the research object, the microstructure and interface actions are investigated by X-ray diffractometer, scanning electron microscope, transmission electron microscope, etc. The results show that as the sintering temperature increases, the interface reaction between SiC and Al intensifies, producing brittle phase Al₄C₃ and MgAl₂O₄ and MgO interface products. The nucleation and growth of Al₄C₃ are controlled by the sintering temperature and time. When preparing large-size workpieces with high volume fraction SiCp/6061Al-based composite materials, the sintering temperature should be controlled below $670^{\circ }$C, and the holding time should not exceed 24 h.