Analysis of ductile fracture using a micromechanics-based coupled damage-plasticity model

The prediction of ductile fracture under low triaxiality shear dominated loadings is of significant technological interest. Here, we use an extension of the Gurson model that accounts for localized modes of plasticity at the micro-scale to predict the ductilities of macro-scale specimens under low triaxiality loading conditions. The model is integrated for various radial loading paths in stress space and predictions for ductility are obtained from the condition of the onset of plastic instability at the macro-scale. It is seen that the loading path dependence of the predicted ductility is consistent with recent experimental data from the literature.