The tensile damage behavior of SiCf/SiC composites after oxidation in wet atmosphere

Due to the low density, oxidation resistance, and high-temperature mechanical strength, SiCf/SiC f /SiC composites have been recognized as potential materials for high-temperature components deployed in the hot sections of gas turbines. In order to investigate the damage evolution of SiCf/SiC f /SiC composites in wet-oxygen environments, the acoustic emission (AE) technique was utilized to analyze changes in damage behavior following heat treatment at temperatures of 1050 degrees C and 1350 degrees C for 0.25h and 16h. The mechanical properties and failure mechanisms of SiCf/SiC f /SiC composites are significantly influenced by the interfaces, as demonstrated by the results of multiple characterization methods. Meanwhile, the AE signal results reveal that the optimal number of clusters shifts from 4 to 2 due to changes in the interface state during the damage behavior of the composites after oxidation. In addition, the SR-mu CT is employed for identifying the internal damage evolution of as-received SiCf/SiC f /SiC composites. The usage of SR-mu CT enables the visualization, localization, and identification of all damage present in composites, thus enabling the determination of the physical origin of the decrease in strength and AE signals. By combining the results, a more comprehensive understanding of the damage evolution in SiCf/SiC f /SiC composites has been achieved, serving as a valuable reference for analyzing AE signals and providing a thorough and precise explanation of the underlying mechanisms involved in the damage process.