Fabrication in-situ SiC nanowires-SiC coating for Carbon/Carbon composites by pack cementation and its tough property for outer SiC coating by CVD

摘要

C/C composites will oxidize at 723 K in ambient environment, which limits their use at high temperature [1-3]. To solve this problem, multilayer coatings are one of the best methods. There is a common ground of multilayer coatings that SiC coating was used as internal buffer layer, because SiC coating has excellent oxidation resistance and good compatibility with C/C substrates [4, 5]. However, multilayer coatings always encounter cracking during thermal cycle experiment. So reinforcement material should be introduced in the outer layer coatings to improve their toughness. Therefore, SiC nanowires have been used in coatings as the reinforcements.