Comparison of ductile failure models using a simple elastic–plastic based degradation model

In material fracture, crack initiation and growth are regarded as a characteristic outcome from a gradual loss of material integrity. In this paper the aforementioned loss of integrity is modelled using an approach to ductile fracture, whereby the elastic properties of the material are modified to simulate material degradation. This is achieved by reducing the element stiffness to zero once the damage variable has reached a critical failure index. A Fortran program has been written and incorporated into ABAQUS finite element software to determine and monitor the prevailing damage in the material. To assess the usefulness of this model, a comparison of two ductile failure criteria were carried out on a one-stage wire drawing configuration. The results are compared with published results, which highlights the applicability in view of its practical implementation to simulate forming processes.