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采用CVI工艺均热法共沉积技术制备了碳纤维增强C－SiC梯度基复合材料。C和SiC的原料气体分别是C2H2和CH3SiCl3，Ar和H2分别是载流和稀释气体。基体微观结构的变化通过控制原料气体的成分配比获得。测试了材料的力学性能、抗氧化性能和摩擦磨损性能。利用金相技术、电子探针成分分析技术、TEM和SEM技术观察和分析了材料的微观结构。试验结果表明，这种材料的组织结构特点是：在微观上是梯度的，即围绕着纤维的基体成分连续地从碳变化到SiC；在宏观上，它属于均质的热结构复合材料。弥散在基体中的SiC起到基体改性的作用，基体壳层外边的SiC起到涂层的作用，因此它的抗氧化性能明显优于C／C材料。
Carbon fiber reinforced C-SiC gradient matrix composites were prepared by CVI CSP process. The feed gases for C and SiC are C2H2 and CH3SiCl3, respectively, and Ar and H2 are the carrier and diluent gases, respectively. The change of the microstructure of the matrix is obtained by controlling the composition ratio of the raw material gas. The mechanical properties, oxidation resistance and friction and wear properties of the materials were tested. The microstructure of the material was observed and analyzed by means of metallographic techniques, electron probe composition analysis, TEM and SEM. The experimental results show that the microstructure of this material is characterized by a microscopic gradient, that is, the matrix composition around the fibers continuously changes from carbon to SiC; macroscopically it is a homogeneous thermal structure composite. The SiC dispersed in the matrix plays the role of matrix modification. The SiC outside the matrix shell acts as a coating, so its oxidation resistance is obviously better than the C / C material.