Abstract
The initial state of crack propagation for the push-out test was analyzed using finite element method. The effects of thermal residual stress and the surrounding fibers were considered in the calculation of the energy release rate. The comparison of the energy release for the cracks at the indenter side and the support side indicates the following conclusion: The lower matrix modulus corresponding to polymer matrix composites yields the on set of delamination from the support side; the higher matrix modulus corresponding to the ceramic matrix composites yields the onset of delamination from the indenter side. Then, this analysis was tried to apply for the results of the push-out test for a glass matrix composite, SiC/LAS (LithiumAluminosilicateGlass). Scanning electron microscopy indicated the existence of the coating carbon layer delamination of the length of 5µm only at the tip of the indenterside. The slope of experimental load-displacement diagram agreed with that of FEM simulation where perfect bonding of interface was assumed. The interfacial fracture toughness of SiC/LAS was calculated to be 26J/m2 from the push-out displacement and the initial delamination length.
