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研究了ＴｉＣ的添加对Ｃ－ＳｉＣ－Ｂ４Ｃ复合材料氧化行为的影响，实验发现１５７３Ｋ处理的Ｃ－ＳｉＣ－Ｂ４Ｃ复合材料的抗氧化性能优于未加ＴｉＣ的复合材料，氧化失重随着ＴｉＣ添加量的增大而减小；更高温度处理的Ｃ－ＳｉＣ－Ｂ４Ｃ复合材料在低温氧化时表现为少量增重，１１００Ｋ以下基本无失重，而高温氧化速率则有所增加，特别是２６７３Ｋ处理的复合材料的最终氧化失重是１５７３Ｋ处理复合材料失重的６倍，失重主要发生在１２００～１４００Ｋ。Ｘ射线衍射发现，高温处理使复合材料中的Ｂ４Ｃ与ＴｉＣ发生反应生成ＴｉＢ２，减缓了Ｂ４Ｃ的氧化速率，使之在１１００～１４００Ｋ不能产生足够的液相Ｂ２Ｏ３，没有起到有效封闭炭材料裸露面而阻止氧的扩散的作用。１４００Ｋ以上的氧化失重速率受热处理温度的影响不大，主要是由于生成的ＴｉＢ２大量氧化，生成Ｂ２Ｏ３液相，以及ＳｉＣ大量氧化生成ＳｉＯ２，从而对复合材料起到保护作用。ＳＥＭ形貌观察与上述结论一致。
The effect of TiC addition on the oxidation behavior of C-SiC-B4C composites was studied. It was found that the oxidation resistance of C-SiC-B4C composites treated with 1573K was better than that without TiC addition. C-SiC-B4C composites treated at higher temperature showed a small amount of weight gain at low temperature, almost no weight loss under 1100K, and high temperature oxidation rate increased, especially the 2673K-treated composite The final oxidation weight loss of the material is 6 times the weight loss of the 1573K treated composite, and the weight loss occurs mainly between 1200 and 1400K. X-ray diffraction found that high temperature treatment makes the composite material B4C and TiC react TiB2, slowing the oxidation rate of B4C, so that 1100 ~ 1400K can not produce enough liquid B2O3, did not play an effective closed carbon material exposed surface And stop the role of oxygen diffusion. The rate of oxidation and weight loss above 1400 K is not significantly affected by the heat treatment temperature. It is mainly due to the large amount of oxidation of TiB2 and the formation of liquid phase of B2O3, as well as the massive oxidation of SiC to form SiO2, thus protecting the composite material. The SEM morphology observation is consistent with the above conclusion.