A synergistic model of stress and oxidation induced damage and failure in silicon carbide-based ceramic matrix composites

A micromechanics-based modeling approach that allows for the simultaneous consideration of deformation, damage, and oxidation associated with each constituent of silicon carbide (SiC)-based ceramic matrix composites (CMC), including the fiber, fiber coating, and matrix, is described. Chemical kinetics models from the literature are combined with a progressive damage model. Rupture predictions of unnotched and notched stress-hold (creep) specimens are compared with experimental measurements from a SiC/SiC CMC to assess the efficacy of the modeling approach. Techniques of improving creep rupture life are explored using the model.