炭/炭复合材料用SiC-Glass涂层的高温氧化机理  

Oxidation mechanism of SiC-Glass coating for protecting carbon/carbon composites from oxidation at high temperatures

作　　者：李龙[1] 曾燮榕[1] 李贺军[2] 谢盛辉[1] 熊信柏[1] 邹继兆[2] 唐汉玲[2] 

机构地区：[1]深圳大学材料学院 [2]西北工业大学材料学院,西安710072

出　　处：《复合材料学报》2007年第5期113-118,共6页Acta Materiae Compositae Sinica

基　　金：国家自然科学基金(50672059);广东省自然科学基金(021299)

摘　　要：采用包埋法和预涂-烧结法相结合的组合工艺在炭/炭（C/C）复合材料表面制得SiC-Glass复合涂层,并借助X射线衍射仪（XRD）和扫描电镜（SEM）对该复合涂层进行了表征,研究了涂层C/C试样在不同温度下的氧化动力学规律。结果表明：复合涂层具有双层结构,包埋SiC内层由-βSiC相和少量游离硅相组成,外层由MoSi2颗粒掺杂的硼硅酸盐玻璃构成;内外层之间结合紧密;在1300-1600℃的空气气氛中,SiC-Glass涂层表现出良好的抗氧化性能,其氧化激活能为118.1 kJ/mol,氧化主要受控于氧在Glass层中的体扩散速率;在1600℃空气气氛中氧化65 h后,SiC-Glass涂层C/C试样的氧化失重率仅为1.02%。An SiC-Glass multi-layer coating was fabricated on the carbon/carbon （C/C） composites by using the pack cementation technique and the precoating-sintering process. The as-prepared multi-layer was characterized by XRD and SEM analyses. The oxidation kinetics of the coated C/C samples was also investigated at different temperatures. The results indicate that the multi-coating is composed of two layers. The inner layer consist of β-SIC phase and a small quantity of silicon phase. The outer layer is a borosilicate glass layer modified by MoSiz particles. Addi- tionally, the multi- coating has good interface bonding between the two layers. The experimental data of the oxidation tests show that the SiC-Glass coating exhibits an excellent oxidation resistance in air in the temperature range from 1300 ℃ to 1600 ℃, and the oxidation activation energy of the coated C/C is 118.1 kJ/mol. After oxidation at 1600 ℃ in air for 65 hours, the mass loss of the SiC-Glass coated sample is only 1.02%.

关 键 词：炭/炭复合材料 抗氧化 涂层 

分 类 号：TB332[一般工业技术—材料科学与工程]