Damage Modelling in Cold Forging Process Chains

The effectiveness of modelling material formability in cold forging process chains often depends on the correct calibration of damage criteria under specific stress and strain conditions. The paper presents a novel approach to describe the ductile damage initiation and model its evolution in cold forging process chains, which is based on the correlation of material formability and the stress state of the deformed mate-rial. The proposed methodology, combined with the choice of a proper damage model, provides a general approach to describe the ductile fracture propagation, not being dependent on the strain conditions of the specific forging step. The approach was applied to a reference forging sequence, proving its suitability in predicting the material ductile fracture unlike conventional damage formulations.