Keywords: Ductile fracture Damage plasticity

Maximum shear stress time consuming process. This is due to the experimental difficulties in maintaining a con-[10–13]. Recent development in ductile fracture modeling has extended the conventional I1, J2 type of continuum damage plasticity theory in the stress invariant space to a full three-dimensional description of plastic damage which incorporates all three stress invariants [14]. In this formulation of damage plasticity model, reference loading paths of proportional loadings under constant pressure and constant Lode angle are adopted. The joint effects of the pressure and the Lode angle on the ductile fracture initiation are represented by a fracture strain envelope. The damage accumulation is thus expressed in term