Damage Evolution in Ductile Materials

A continuum damage evolution model for ductile materials is derived from the principles of incremental complementary energy and thermodynamics. In accordance with this model, the evolution of damage is dependent on the accumulated strain, the stress triaxiality ratio, and the strain hardening exponent of the material. The predictions of the model are compared with experimental results and it showed that the model is capable of predicting damage evolution with good accuracy. It is also found that of the three factors affecting damage evolution in ductile materials, the stress triaxiality ratio has the greatest influence. The study showed that a faster rate of damage occurs at higher stress triaxiality ratios.