Fracture behavior of monolithic and laminated ultra-high temperature ceramic matrix composites considering effects of temperature and particle/crack interaction

The fracture behavior of ultra-high temperature ceramic matrix composites at high temperature has received increasing attention. However, few studies consider the effect of particle/crack interaction on the high temperature fracture strength. In this work, based on the energy storage capacity, energy balance method and fracture theory, the effect of particle/crack interaction is introduced into a temperature-dependent fracture strength model of monolithic ultra-high temperature ceramic matrix composites, which also considers effects of flaw size, grain size and residual thermal stress. Furthermore, by considering the influence of the laminated structure, a theoretical characterization model of the temperature-dependent fracture strength of laminated ceramic matrix composites is developed. The effect of particle/crack interaction is also included in this model. It should be noted that the predictions of the models agree well with the experimental data of both monolithic and laminated materials without using any fitting parameters. The effect of particle/crack interaction is found to have a significant weakening effect on the strength of materials at different temperatures. The theoretical models only need some simple basic material parameters to predict the fracture strength and mechanisms of ceramic matrix composites at high temperature, which have important practical significance for engineering applications.