A low-temperature preparation strategy of SiC/ZrB2-CrSi2-Si/SiC multilayer oxidation-resistant coating for C/C composites: Process, kinetics and mechanism research

In this work, a strategy of preparing multilayer SiC/ZrB2-CrSi2-Si/SiC coating at low-temperature by combining chemical vapor deposition (CVD), brush-sintering and preoxidation was proposed for C/C composites. The coated C/C composites could maintain stable and long-term oxidation resistance at 1473-1673 K, and the specific mass loss was only 8.05 mg center dot cm-2 after 1673 K/340 h oxidation. The coupling mechanism of the preparation process on the microstructure and performance, the kinetics process of oxidation behavior and the protection/failure mechanism of the coating were analyzed. Furthermore, the importance of organosilicon (SiCxOy) in the process of self-healing and oxidation resistance was enlightened.

Automated summary

The study proposed a strategy for preparing multilayer SiC/ZrB2-CrSi2-Si/SiC coatings at low temperatures, which can enhance the oxidation resistance of C/C composites, and emphasized the importance of organosilicon in the processes of self-healing and oxidation resistance.