TIME-DEPENDENT FAILURE IN FIBER-REINFORCED COMPOSITES BY MATRIX AND INTERFACE SHEAR CREEP

摘要

The inelastic response of fiber-reinforced ceramic and metal matrix composites under fixed load at elevated temperature is due to the complementary effects of creep and damage in the constituents. After matrix cracking or tensile creep relaxation in a short time, subsequent deformation and failure are driven by shear stress relaxation in the matrix and at the fiber-matrix interface around broken fibers. The shear creep causes stress redistribution to unfailed fibers, causing further fiber breakage and shear relaxation, culminating in abrupt failure of the composite.