预氧化C_f/SiC陶瓷基复合材料及其构件的抗疲劳特性研究

In this paper, the two-dimensional (2D) carbon fiber reinforced silicon carbide matrix composites (C_f/SiC) with complex shape were prepared by the online integration technique, and then the vibration fatigue test was carried out to investigate the vibration fatigue life and damage models after the pre-oxidation. The work demonstrated the delamination damage mode at different excitation acceleration, which was caused by the pin fracture, and the delamination joint is weak part of C_f/SiC. Through the analysis of ANSYS stress and microstructure, it can be concluded that, in the vibration test, cracks propagated easily in the interlayer matrix due to the lack of fiber toughening mechanism, and then the stress was concentrated on the pin with the failure of interlayer matrix. So the composites failed by the pin fracture and the interlayer delamination were damaged.