Model of the Nonlinear Mechanical Behavior of 2D SiC-SiC Chemical Vapor Infiltration Composites

An approach to the nonlinear stress–strain behavior of ceramic matrix composites was proposed, based upon damage mechanics. Damage–loading relations taking into account effects of anisotropy and coupling were established. These relations allowed prediction of the stress–strain behavior, and ultimate failure. The theory was then applied to a 2D SiC/SiC composite subject to tensile loading under 0°, 20°, and 45° off‐axis angles. A two‐stage damage mechanism was identified by optical microscopy on specimens under load. Predictions of the stress–strain behavior were in excellent agreement with experimental data.