Fracture mechanisms of an environmental barrier coating under thermomechanical loadings

The introduction of environmental barrier coating (EBC) with SiC/SiC composites in hot components airplanes engines makes it essential to master their behavior in this multiphysical environment. The aim of this paper is to investigate the fracture mechanisms of a CMC/EBC system under thermomechanical loadings, in 4-point bending under thermal gradients. The thermal and mechanical loads, along with coating thickness and cooling durations, are systematically examined to highlight their effect on crack network formation. The findings reveal that temperature gradients, mechanical loads, and cooling durations significantly affect the crack network size, shape, and depth. These results highlight the damage mechanisms and may contribute to future optimization of this type of systems.