Mechanical properties and microstructure evolution of 3D Cf/SiBCN composites at elevated temperatures |
| |
| Authors: | Qi Ding Dewei Ni Zhen Wang Hongda Wang Haijun Zhou Yanmei Kan Shaoming Dong |
| |
| Affiliation: | 1. State Key Laboratory of High Performance Ceramics and Superfine Microstructure, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai, China;2. Structural Ceramics and Composites Engineering Research Center, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai, China;3. University of Chinese Academy of Sciences, Beijing, China;4. ShanghaiTech University, Shanghai, China |
| |
| Abstract: | 3D Cf/SiBCN composites were fabricated by an efficient polymer impregnation and pyrolysis (PIP) method using liquid poly(methylvinyl)borosilazanes as precursor. Mechanical properties and microstructure evolution of the prepared 3D Cf/SiBCN composites at elevated temperatures in the range of 1500‐1700°C were investigated. As temperature increased from room temperature (371 ± 31 MPa, 31 ± 2 GPa) to 1500°C (316 ± 29 MPa, 27 ± 3 GPa), strength and elastic modulus of the composite decreased slightly, which degraded seriously as temperature further increased to 1600°C (92 ± 15 MPa, 12 ± 2 GPa) and 1700°C (84 ± 12 MPa, 11 ± 2GPa). To clarify the conversion of failure mechanisms, interfacial shear strength (IFSS) and microstructure evolution of the 3D Cf/SiBCN composites at different temperatures were investigated in detail. It reveals that the declines of the strength and changes of the IFSS of the composites are strongly related to the defects and SiC nano‐crystals formed in the composites at elevated temperatures. |
| |
| Keywords: | ceramic matrix composites Cf/SiBCN high‐temperature strength interfacial shear strength microstructure |
|
|
