Prediction of damage in cold bulk forming processes

In the present paper a practically relevant extension of the known modelling methods with regard to the description of forming limits of steels typically used in the cold bulk forming is developed and implemented in a commercial finite element code Abaqus. The modeling approach is based on the so-called micromechanical damage concepts which represent the microstructure evolution more detailed than phenomenological models and, therefore, provide better prediction of damage and failure during the forming process. Particularly, the well-known damage models of Gurson as well as Gologanu-Leblond are considered. It is shown that in combination with fracture criteria such models are able to describe failure in bulk forming.