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利用熔盐反应法在由NaCl和KCl组成的混合盐体系中成功地在炭/炭复合材料表面制备出TiC涂层。使用XRD和SEM等方法对涂层的晶相组成和微观形貌进行了分析和观察。研究了涂层试样从室温到1 200℃范围内的氧化行为以及在800℃静态空气中的氧化失重情况。结果表明:在850~950℃内能够在炭/炭复合材料表面制备TiC涂层,在950℃制备的TiC涂层中还含有AlCTi2。随着反应温度的升高,涂层的厚度增加,涂层颗粒尺寸增大。在950℃保温6 h制备的涂层完整均匀,与基体的结合良好,但是在局部区域仍有微小的裂纹存在。高温生成的AlCTi2在一定程度上提高了涂层试样的抗氧化性,涂层后炭/炭复合材料的起始氧化失重温度从原来的450℃升高到800℃左右,氧化12 h的失重率为5.09%。
TiC coating was successfully prepared on the surface of carbon / carbon composites by molten salt reaction in a mixed salt system composed of NaCl and KCl. The crystal phase composition and microstructure of the coating were analyzed and observed by XRD and SEM. The oxidation behavior of the coated samples from room temperature to 1200 ℃ and the oxidation loss in static air at 800 ℃ were investigated. The results show that TiC coating can be prepared on the surface of carbon / carbon composites at 850-950 ℃, and AlCTi2 can also be formed on TiC coating prepared at 950 ℃. As the reaction temperature increases, the thickness of the coating increases and the coating particle size increases. The coatings prepared at 950 ° C for 6 h produced a complete and uniform coating that was well bonded to the matrix, but still had tiny cracks in localized areas. AlCTi2 produced by high temperature improved the oxidation resistance of the coating sample to a certain extent. The initial oxidation loss weight temperature of the coated carbon / carbon composite increased from 450 ℃ to 800 ℃ and the weight loss after 12 h of oxidation The rate was 5.09%.