Macro-micro integrated modeling and analysis method for ceramic matrix composite material structures with stress concentration

Ceramic matrix composite (CMC) structures with different stress concentration levels were initially analyzed based on micro and macro models, and simulation differences, primarily attributable to excessive macro-element reduction after failure, were revealed. This verifies the necessity of micro-modeling CMC structures with stress concentrations. Therefore, a simplified macro–micro integrated modeling and analysis method, combining the efficiency of macro models with the accuracy of micro models, is proposed to reflect damage mechanisms. The rationality of this method for CMC structures with stress concentrations was preliminarily verified through comparison with full micromodel simulations. Additionally, the effects of several factors, such as grid division method, transition position between the micro and macro models, and micro-model size, on the simulation results were analyzed. Furthermore, a micro model of a plate without a hole was established based on X-ray computed tomography (XCT) slices of SiC/SiC woven braided CMCs, and the predicted tensile curve was experimentally verified, confirming the consistency of the material parameters between the micro and macro models. On this basis, a macro–micro integrated model of a plate with a hole was established, and the predicted tensile curve and fracture were verified by experiments, further proving the feasibility of the proposed method.