中國有色金屬學(xué)報(bào)(英文版)
Transactions of Nonferrous Metals Society of China
| Vol. 32 No. 10 October 2022 |
（1. State Key Laboratory of Powder Metallurgy, Central South University, Changsha 410083, China;
2. Science and Technology on Advanced Functional Composites Laboratory, Aerospace Research Institute of Materials and Processing Technology, Beijing 100089, China）
Abstract:To investigate the thermal stability of ceramic-matrix composites, three kinds of C/C-ZrC-SiC composites with different Zr/Si molar ratios were synthesized by reactive melt infiltration. Employing region labeling method, the high-temperature thermal stability of the composites was systematically studied by changing the temperature and holding time of thermal treatment. Results show that the mass loss rate of low Si composites has a growth trend with increasing temperature, and a crystal transformation from β-SiC to α-SiC occurs in the composites. In the calibrated area, SiC phase experiences Ostwald ripening and volume change with location migration, while ZrC phase experiences a re-sintering process with diffusion. Moreover, it is found that increasing temperature has a more obvious effect on the thermal stability than extending holding time, which is mainly attributed to the faster diffusion rate of atoms.
Key words: thermal stability; ceramic-matrix composites; reactive melt infiltration; high-temperature thermal treatment; region labeling method
