采用粉末挤压成型方法制备SiC体积分数分别为30%，40%，50%的SiC_p/Al复合材料，通过光学显微镜、扫描电镜、拉伸试验机、布氏硬度计、热膨胀仪和热导率测试仪等对其显微组织、力学性能和物理性能等进行了分析。结果表明：经过450℃热挤压成型成功制备出30% SiC_p/Al和40% SiC_p/Al复合材料，而50% SiC_p/Al复合材料无法直接挤压成型；在复合材料纵截面上，铝基体沿挤压方向分布并呈现白色条状流线型组织；两种复合材料的拉伸断口均由大量细小韧窝组成，呈混合断裂特征；随着SiC体积分数的提高，复合材料布氏硬度从81.9 HB升高到98 HB，但抗拉强度有所降低，伸长率明显减小；复合材料的相对密度和线膨胀系数减小，热导率增大。

The SiC_p/Al composites with SiC volume fraction of 30%, 40% and 50% were prepared by powder extrusion forming. The microstructure, mechanical properties and physical properties of different SiC_p/Al composites were analyzed by optical microscopy, scanning electron microscopy, tensile tester, brinell hardness tester, thermodilatometer and thermal conductivity detector. The results showed that 30% and 40% SiC_p/Al composites could be extruded in 450℃, but 50% SiC_p/Al composite failed. On longitudinal section of composite, the aluminum matrix was distributed along the extrusion direction and presented the white strip streamline structure. The tensile fracture surface of two composites was made up of a large number of smaller dimples, both of which presented mixed fracture characteristics. With increase of SiC_p volume fraction, the brinell hardness increased from 81.9 HB to 98 HB while tensile strength decreased slightly and the elongation reduced obviously. The relative density and coefficient of linear expansion of the composite reduced while thermal conductivity improved.