The energy release rate for an interfacial debond crack in a fiber pull-out model

The energy release rate for an interfacial debond crack in a ceramic-matrix composite has been derived by the use of the Lamé solution for an axisymmetric cylindrical fiber/matrix model. The energy release rate expression includes the important effects of compressive residual stresses and frictional sliding stress on the debonded interface in closed form. A parametric study of the energy release rate is carried out and the effects of various parameters on the energy release rate are clarified. A method of determining the critical interfacial debond length is proposed and is shown to provide more physical insight into the debonding phenomenon on the basis of the energy release rate and the fracture criterion of the interface.