Equivalent configurational stress to predict material yielding and crack propagation

Abstract

The concept of material configurational stress (or called Eshelby stress) is used to describe the material yielding state and to predict the crack propagation in this paper. The equivalent configurational stress $(b_{v})$ is introduced to successfully describe the elastic–plastic boundary near the crack tip. Moreover, the crack propagation initiation is predicted by the total change in potential energy calculated from the magnitude of $b_{v}$ stored inside the plastic zone reaching a critical value; and the crack propagation is stipulated to take place in the direction ahead of the crack tip along which the distance between the crack tip and the elastic–plastic boundary possesses a stationary minimum value. The validation of the proposed yielding and fracture criteria via configurational stress is addressed by comparing with other theories and experiments.