Comparison between Lemaitre and Gurson Damage Models in Crack Growth Simulation during Blanking Process

摘要

The paper describes the initiation and propagation of cracks during the process evolution in the case of sheet metal blanking process. The numerical results obtained by a finite element analysis are compared with experimental ones in order to verify the validity of Gurson and Lemaitre damage models. The concept of continuum damage mechanics has been retained to describe the progressive damage accumulation into the sheet metal leading to the final rupture. During the analysis, the crack propagation is simulated by the propagation of a completely damaged area. The comparative study between the results obtained by the simulations using the different damage models and the experimental ones, show that Gurson damage model is not able to predict the fracture propagation-path in a realistic way. Only Lemaitre damage model gives good results.