Interfacial modification and oxidation resistance behavior of a CVD-SiC coating for C/SiC composites

The root structure was introduced to mainly improve the oxidation resistance and bonding strength of chemical vapor deposition (CVD) SiC coating on C/SiC composites. The microstructure, phase composition, bonding strength, and thermal cycling performance of SiC coatings with root structure were investigated. The results indicated that the designed and prepared root structure, consisting of pores and SiC nanowires, improved the bonding strength between the matrix and SiC coating. The tensile strength of the coating increased to over 4.67 MPa. The root structure reduced coating cracking or spalling by relieving thermal stress, inhibiting the propagation of cracks, and improving bonding strength. The oxidation resistance of coating could be effectively increased. After 9 thermal cycles between 1873 K and room temperature, the weight loss was only 0.48 wt%.