Double SiC coating on carbon/carbon composites against oxidation by a two-step method  

C/C复合材料表面两步法制备SiC涂层的抗氧化性能(英文)

作　　者：孙粲[1] 李贺军[1] 付前刚[1] 张佳平[1] 彭晗[1] 

机构地区：[1]西北工业大学 凝固技术国家重点实验室,西安710072

出　　处：《Transactions of Nonferrous Metals Society of China》2013年第7期2107-2112,共6页中国有色金属学报（英文版）

基　　金：Projects(51221001,51222207)supported by the National Natural Science Foundation of China;Project(090677)supported by the Program for New Century Excellent Talents in University of Ministry of Education of China;Project(B08040)supported by the Program of Introducing Talents of Discipline to Universities (111 Project) of China

摘　　要：To improve the oxidation resistance of C/C composites, a double SiC protective coating was prepared by a two-step technique. Firstly, the inner SiC layer was prepared by a pack cementation technique, and then an outer uniform and compact SiC coating was obtained by low pressure chemical vapor deposition. The microstructures and phase compositions of the coatings were characterized by SEM, EDS and XRD analyses. Oxidation behaviour of the SiC coated C/C composites was also investigated. It was found that the double SiC coating could protect C/C composites against oxidation at 1773 K in air for 178 h with a mass loss of 1.25%. The coated samples also underwent thermal shocks between 1773 K and room temperature 16 times. The mass loss of the coated C/C composites was only 2.74%. Double SiC layer structures were uniform and dense, and can suppress the generation of thermal stresses, facilitating an excellent anti-oxidation coating.为了提高炭/炭(C/C)复合材料的抗氧化性能,采用包埋与低压化学气相沉积相结合的方法在C/C复合材料表面制备双层SiC涂层。利用SEM、XRD和EDS观察与分析涂层的微观形貌和相组成;测试涂层试样在1773K高温下的抗氧化性能。结果表明:双层SiC涂层可以在1773K的高温下有效地保护C/C复合材料178h,质量损失仅为1.25%。试样经受16次1773K至室温急冷急热循环后,氧化质量损失仅为2.74%。C/C复合材料表面双层SiC涂层的结构致密、成分均匀,具有较强的抗氧化性能。

关 键 词：carbon/carbon composites SIC OXIDATION COATING 

分 类 号：TB332[一般工业技术—材料科学与工程] TB306