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本文对原位反应合成的C-SiC-TiC-TiB2复合材料在600～1200℃空气中的抗氧化性进行了研究．在不同材料组成和试验温度下，试样分别出现氧化增重和失重，这主要取决于碳相和陶瓷相的氧化速率及氧化层的结构特征．在600℃该材料几乎不被氧化；800℃时，TiB2被优先氧化，形成B2O3液相；在1000℃以上，B2O3与SiO2生成硼硅酸盐玻璃，形成一致密氧化层．氧化过程中液相的出现和致密氧化层的形成显著降低了氧化速率，使材料进入钝氧化，从而大幅度地提高了该材料的抗氧化能力．
In this paper, the in situ oxidation reaction of C-SiC-TiC-TiB2 composites synthesized in situ at 600 ~ 1200 ℃ was studied. At different material compositions and test temperatures, the samples showed oxidation weight gain and weight loss, respectively, depending on the oxidation rate of the carbon and ceramic phases and the structural characteristics of the oxide layer. At 600 ℃, the material is almost not oxidized. At 800 ℃, TiB2 is preferentially oxidized to form B2O3 liquid phase. Above 1000 ℃, B2O3 and SiO2 form borosilicate glass to form a dense oxide layer. The appearance of liquid phase and the formation of dense oxide layer in the oxidation process significantly reduce the oxidation rate and make the material enter blunt oxidation, thereby greatly improving the oxidation resistance of the material.