Scaler nonlinear continuum damage models for ceramic matrix composites with and without in plane ply anisotropy at room temperature

Abstract

Listen

Translate article

Damage tolerant design of aerospace structures with continuous fiber reinforced ceramic matrix composites (CMCs) require progressive damage models that can predict the behavior at local stress concentrations. Here we introduce three versions of a continuum damage model including a two-variable damage model that considers damage formulation perpendicular and in line with the direction of the primary fiber reinforcement, a coupled two-variable damage model and a four-variable damage model that includes the previously mentioned modes along with two additional modes specific to shear damage. The model is demonstrated using data for two different SiC/SiC CMCs including one that consists of stacks of balanced woven plies and one that consists of stacks of unidirectional laminate-based plies. The behavior is well captured for the balanced woven ply-based materials, but required a more complex damage formulation to close the solution for the unidirectional based plies that exhibited a significant degree of anisotropy.