Fracture mechanics investigation of interacting defects in composite materials

Abstract

With the increasing applications of composite materials in various engineering structures, failure analysis on crack induced fracture problems in composite materials has attracted more and more attention among researchers. In the current work, with the plastic zone corrections, the elastic-plastic fracture behavior investigations on crack problems in different configurations have been carried out. Two approaches of plastic zone correction are demonstrated. The first one is the mixed-mode Dugdale model for interface cracks and the second one is the generalized Irwin model which is suitable for matrix cracking. The introduction of plastic zone can greatly improve the accuracy of fracture prediction in fiber-reinforced composite materials with ductile matrix. Based on the two models, the problem of a crack lying at the interface of two semi-infinite plate, and crack-coated inclusion interactions have been studied. Numerical examples are given to show the influence of different kinds of parameters on the plastic zone size and crack tip opening displacement of each problems. Some useful conclusions have been figured out after the investigation.