Acoustic Emission Pattern Recognition in Stress-Corrosion Behavior of Sicf/Sic Under Cmas-Wet-Oxygen Environments

Abstract

As structural materials used in aeroengine hot sections, SiCf/SiC composites suffer from severe degradation under steam/salt-corrosion/stress associated working environments. Here, synergistic effects of molten CMAS, water vapor and external stress on the degradation of SiCf/SiC are investigated using acoustic emission technique. The composite performance is closely related to the ambient temperature. Interphase/fiber debonding mode at 1100 °C is changed into interphase/matrix debonding at 1300 °C. Based on microstructure changes, further analysis is conducted on the damage behavior through acoustic emission signals. This work can provide reference for microstructure design of SiCf/SiC with high stability under corrosion environments.

Keywords: Acoustic emission, CMAS-wet-oxygen, SiCf/SiC, Tensile behavior, Corrosion Mechanism