Analyses of residual thermal stresses in ceramic matrix composites

摘要

Residual thermal stresses in ceramic matrix composites containing either ellipsoidal inclusions or short fibers (i.e., fibers of finite length) are considered. First, the residual stresses in ellipsoidal inclusions are uniform, and they are analyzed using a modified Eshelby model. Although closed-form analytical solutions are obtained, their formulations are formidable. When the aspect ratio of the ellipsoid is 0, 1, or infinity, simple analytical solutions can be obtained using different models, and they are in excellent agreement with those obtained from the modified Eshelby model. Second, residual stresses in short fibers are nonuniform, and they are analyzed using a modified shear lag model, in which imaginary fibers are introduced to satisfy the continuity condition at the fiber ends. The analytical solutions are compared to the experimental results.