中文摘要：

采用无压浸渗法制备出了体积分数为55%~70%的SiCp/Al复合材料,并对其反应机理、组织形貌以及热物理性能进行了研究。XRD及热力学分析表明：复合材料在制备的过程中最可能发生的界面反应为SiO2（s）＋Al（l）＋MgO（s）→MgAl2O4（s）＋Si（s）,提高Si元素的活度可以有效抑制有害界面产物Al4C3的生成;金相显微分析表明：复合材料组织均匀,结构致密,在复合材料制备过程中易产生浸渗缺陷;热物理研究表明：浸渗缺陷较少,结构致密的复合材料其最佳热导（TC）和热膨胀系数（CTE）分别为170.2 W/（m·K）和6.64×10-6K-1。

英文摘要：

SiC p/Al composites of 55%~70%（volume fraction） were prepared by pressureless infiltration to investigate the reaction mechanism, morphology and the thermo-physical properties of the prepared composites. X-ray diffraction（XRD） and thermodynamic analyses show that the main interface reaction may be SiO 2（s）＋Al（l）＋Mg O（s）→Mg Al2O4（s）＋Si（s） in the preparation process of the composites. The enhancing of Si activity can obviously suppresses the formation of harmful interface reaction product Al4C3. Metallographic observation shows that the microstructures of the composites are homogenous and dense, infiltration defects are liable to occur in the preparation process. The thermo-physical tests show that the best thermal conductivity（TC） and the coefficient of thermal expansion（CTE） for the prepared SiC p/Al composites with less infiltration defects and dense structure are170.2 W/（m·K） and 6.64×10^-6 K^-1, respectively.