C/SiC复合材料在1700℃下氧化机制研究  

High-temperature oxidation of C/SiC composites at 1700 ℃

作　　者：王芙愿 王毅[1] 杨晓辉[1] 白龙腾[1] 

机构地区：[1]西安航天动力研究所,陕西西安710100

出　　处：《火箭推进》2017年第6期82-87,共6页Journal of Rocket Propulsion

摘　　要：以沉积SiC涂层的C/SiC复合材料为研究对象,利用扫描电镜对复合材料表面进行观察分析,研究了复合材料在1 700℃下空氧环境中显微结构和成分演变。结果表明在1 700℃下,复合材料的氧化过程主要受到氧气在氧化膜中的扩散控制。C相在氧化过程中以气体的形式消耗殆尽,SiC相氧化形成氧化膜,覆盖在试样表面。由于SiC相氧化过程中伴随气体副产物的释放,在氧化膜中形成大量裂纹。这些裂纹的存在进一步加剧了复合材料的氧化损伤。The C/SiC composite with SiC coating is taken as the research object. The surface change of the composite before and after oxidation is observed and analyzed with an scanning electron microscope to study the microstructure and composition evolution of the composite at 1 700 ℃ in air and oxygen environment, oxidation mechanism, in The results indicate that the oxidation process of C/SiC composite at 1 700 ℃ is mainly controlled by the oxygen diffusion in the oxide film. In the oxidation process, C phase is oxidized and consumed in gas phase, SiC was oxidized and converted into oxide film covering on the sample surface. Because of the volatilization of gas byproduct during SiC oxidation, many cracks appear in oxide film. At high temperature, these cracks become the channel of oxidizing mediums coming into the internal of C/SiC composite, which would accelerate oxidation of C/SiC.

关 键 词：C/SIC复合材料 高温氧化 扩散控制 氧化膜 

分 类 号：V250-34[一般工业技术—材料科学与工程]