炭/炭复合材料C/SiC/MoSi2-SiC-Si抗氧化复合涂层

摘要

采用包埋法和料浆涂刷法在C/C复合材料表面制备C/SiC/MoSi2−SiC−Si抗氧化复合涂层。通过扫描电镜(SEM)、电子能谱(EDS)以及X射线衍射(XRD)等测试手段对涂层的微观结构、元素分布及晶相组成进行分析，研究涂层试件在1873 K静态空气下的抗氧化性能。结果表明：制备的复合涂层主要由MoSi2、SiC和Si构成；其在1873 K静态空气下有效保护C/C复合材料达200 h，带涂层的C/C复合材料试样氧化失重率仅为3.25%。涂层试样的氧化失重主要是由于涂层表面SiO2的挥发及裂纹、孔洞等缺陷的形成引起的。%C/SiC/MoSi2−SiC−Si oxidation protective multilayer coating for carbon/carbon (C/C) composites was prepared by pack cementation and slurry method. The microstructure, element distribution and phase composition of the as-received coating were analyzed by scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS) and X-ray diffraction (XRD). The results show that the multilayer coating was composed of MoSi2, SiC and Si. It could effectively protect C/C composites against oxidation for 200 h with the mass loss of 3.25%at 1873 K in static air. The mass loss of the coated C/C composites results from the volatilization of SiO2 and the formation of cracks and bubble holes in the coating.