Effect of interface oxidation on matrix multi-cracking evolution of fiber-reinforced ceramic-matrix composites at elevated temperature

摘要

In this paper, the effect of fiber/matrix interface oxidation on matrix multi-cracking evolution of fiber-reinforced ceramic-matrix composites (CMCs) is investigated using the critical matrix strain energy (CMSE) criterion. The shearlag model combined with the fiber/matrix interface oxidation model and fiber/matrix interface debonding criterion is adopted to analyze the fiber and matrix axial stress distribution inside of the damaged composite. The relationships between matrix multi-cracking, fiber/matrix interface debonding and oxidation are established. The effects of fiber volume fraction, fiber/matrix interface shear stress, fiber/matrix interface debonded energy, oxidation temperature and oxidation time on the stress-dependent matrix multi-cracking development are discussed. Comparisons of matrix multi-cracking evolution with/without oxidation are analyzed. The experimental matrix multi-cracking development of unidirectional C/SiC, SiC/CAS, SiC/Borosilicate and mini-SiC/SiC composites with/without oxidation are predicted.