(中国科学院 金属研究所 沈阳材料科学国家(联合)实验室，
沈阳 110016)
摘 要: 采用固体粉末包埋法在Ti3SiC2陶瓷上渗硅，研究了渗硅涂层的抗高温氧化性能，用XRD及SEM/EDS分析了渗硅涂层及其氧化后产物的成分、结构和形貌等。结果表明：渗硅层主要由TiSi2和SiC组成，在空气中氧化时形成了SiO2和TiO2的混合氧化物膜。渗硅样品在1100℃和 1200℃下的恒温氧化速率比Ti3SiC2降低了2～3个数量级，1100℃下抗循环氧化性能也优于Ti3SiC2。但由于渗硅层中存在裂纹，循环过程中当裂纹贯穿整个渗硅层时，涂层的氧化速度开始增加，其保护作用逐步退化。在1100℃下空气中循环氧化时，经400次循环后涂层已基本失效。
关键字: 钛碳化硅；渗硅；高温氧化；涂层
coatings on Ti3SiC2-based ceramic
（Shenyang National Laboratory for Materials Science，
Institute of Metal Research，The Chinese Academy of Sciences，
Shenyang 110016, China）
Abstract:Silicide coating was prepared on Ti3SiC2 base ceramic by pack cementation. The microstructure，phases and oxidation resistance of the coating were investigated. The results show that, the silicide coating is mainly composed of TiSi2 and SiC; one layer of the mixture of SiO2 and TiO2 is formed when the coating is oxidized. At 1100℃ and 1200℃，the oxidation rate of silicide coating is 2～3 order lower than that of Ti3SiC2. The cyclic oxidation resistance of the coating is much higher than that of Ti3SiC2. There are a great number of fine cracks in the outer layer of the coating. When these cracks penetrate whole coating during the cyclic oxidation，the oxidation rate begins to increase，which is the main reason for the loss of the protection of coating.
Key words: titanium silicon carbide ceramic; silicidation; oxidation; coating
