ZrB2–20MoSi2 Composite Coating for Carbon/Carbon Composites Prepared by a New Multi-Chamber Detonation Accelerator

in order to improve the oxidation resistance of carbon-carbon (C/C) composites at high temperature, composite ZrB2–20MoSi2 coating modified by Y2O3 and Al was prepared by a new multi-chamber detonation accelerator. Its microstructure and oxidation behavior at 1500°C in air for 1 h were characterized by X-ray diffraction and scanning electron microscopy. As-sprayed coating consisted of m-ZrO 2 , t-ZrO 2 , and h-ZrB 2 . The m-ZrO 2 , c-ZrO 2 and h-(α-Al 2 O 3 ) were formed at 1500°C. As a result, it found that no cracks and pores appear on the surface of the coating after oxidation. The dense uniform microstructure of the ZrB 2 –20MoSi 2 coating contributed to its good oxidation-resistant property at high temperature. Y 2 O 3 restrain the phase transition of ZrO 2 to reduce the formation of thermal stresses of the coating; the uniform distribution of ZrO 2 ceramic particles and the formation of α-Al 2 O 3 enhanced the stability of the coating.