Experimental study of dynamic properties of CMC flat plates in oxidative environment

Accelerated failure of CMC (Ceramic Matrix Composites) structural components in aero engines occurs under oxidative vibrational environments. This study investigates the failure mechanisms of CMCs under high-temperature oxidative vibrational conditions. Experiments were conducted to measure the vibrational response of CMC plates at 1200°C in oxygenated, non-oxygenated, and non-vibrational environments. Combined with techniques such as Energy-Dispersive X-ray Spectroscopy (EDS) and thermogravimetric analysis, the failure mechanisms of CMCs in oxidative vibrational environments were elucidated. The research results indicate that oxidation leads to a decline in the mass and mechanical properties of CMCs, resulting in a reduction in the natural frequency and response amplitude of CMC structures. The presence of vibrational loads causes the opening of matrix cracks, accelerating the oxidation of fibers within the CMC, thereby leading to a more significant decline in CMC plates’ performance and dynamic response.