SiC/MoSi2-Si-Cr-B/玻璃涂层炭/炭复合材料抗氧化行为研究-中国材料进展

文章信息/Info

Title:: Research on the Anti-oxidation Behavior of SiC/MoSi2-Si-Cr-B/Glass Compound Coating on Carbon/Carbon Composites

作者:: 杨茜1; 2; 李贺军1; 冯涛1; 张守阳1; 齐乐华1; （1西北工业大学超高温复合材料重点实验室碳/碳复合材料工程技术研究中心，陕西西安 710072）
（2河南科技大学材料学院，河南洛阳 471023）

Author(s):: YANG Xi1; 2; LI Hejun1; FENG Tao1; ZHANG Shouyang1; QI Lehua1; (1. C/C Composite Research Center, Key Laboratory of Thermal Structural Composites, Northwestern Polytechnical University, Xin 710072, China )
(2. School of Materials, Henan University of Science and Technology, Luoyang 471023, China)

摘要:: 采用两步包埋法及料浆涂刷-烧结法在二维碳布叠层碳/碳复合材料表面依次制备了SiC/MoSi2SiCrB包埋涂层及磷酸盐玻璃外涂层，研究了其在950 ℃静态空气环境中自由状态的抗热震、防氧化性能及不同弯曲变形状态下的防氧化性能，并借助X射线衍射分析仪及扫描电子显微镜对涂层试样的组成成分及微观组织形貌进行了分析。结果表明：950 ℃自由状态下该涂层体系的氧化失重率为负值，抗热震、防氧化效果良好；磷酸盐玻璃层在950 ℃软化熔融呈粘流态，可填补涂层内的裂纹和孔洞，阻止氧的入侵，有效提高了涂层整体的抗热震及抗氧化性能；但弯曲变形状态下，涂层试样的氧化失重率随形变量的增加而提高，形变会在一定程度上降低碳/碳复合材料抗氧化涂层的保护效果，加速材料的氧化失效。

Abstract:: The compound coating composed of SiC/MoSi2-Si-Cr-B layer and phosphate爂lass outer layer was prepared on the surface of 2D carbon cloth laminated carbon/carbon composites by two-step pack cementation and slurry-sintering techniques. At 950℃, the anti-oxidation performance of coated samples was evaluated in free-state and states?with?different?deformations, respectively. In addition, thermal shock test was also conducted from 950℃ to room temperature. The phase composition and microstructure of the as-prepared coating were characterized by XRD and SEM. The results show that the coating exhibits favorable thermal shock resistance and anti-oxidation properties, with a negative weight loss rate at 950℃. The phosphate?glass will be melted into a viscous-flow state at 950℃. It could seal the cracks and holes, resulting in the improvement of the thermal shock and oxidation resistance of the compound coating. However, under the bending state, the oxidation weight loss rate increases with the increase of deformation. The deformation will reduce the protective effect of anti-oxidation coating to some extent, accelerating the oxidation failure of carbon/carbon composites