PREDICTION OF THE INITIATION OF DUCTILE FRACTURE

The initiation of a ductile tear at a sharp notch is modelled by the g rowth of an isolated void embedded in a J-Q stress field. This model g ives the predicted value of J at the initiation of a ductile tear, for any geometry and size, in terms of its value for a standard test spec imen. Experimental data from a wide range of specimen geometries, both new and previously published data, are presented in support of the ne w model.