Modeling the temperature-dependent non-steady state first matrix cracking stress for fiber ceramic matrix composites

Abstract

Based on fracture mechanics theory and a temperature-dependent interfacial shear strength model established by the authors, this paper develops a temperature-dependent theoretical model for the non-steady state first matrix cracking stress of fiber ceramic matrix composites. The model unifies the combined effects of temperature, crack length and thermal residual stress on the first matrix cracking stress into a single theory. The model predictions for the first matrix cracking stress of silicon carbide fiber reinforced zircon matrix composite agree well with the experimental results. Compared with the classical models proposed by Danchaivijit and Shetty, Thouless and Evans, and Marshall et al., our model has obvious advantages from the aspects of applicability, convenience and accuracy. Moreover, the analysis of influencing factors for the first matrix cracking stress is conducted systematically. Some new insights into improving the first matrix cracking stress of fiber ceramic matrix composites are obtained.