Simulation of crack arrest in blanking using the node separation method

A crack is arrested during blanking when the clearance between the punch and the die is relatively small. Simulation of the arrest of a crack during blanking is performed using the node separation method. When a crack is arrested, one fracture surface contacts another fracture surface in the region near the arrested crack. Therefore, a simplified simulation method is proposed for the material contact. Special attention is given to the effect of various kinds of ductile fracture criteria on crack initiation and propagation during blanking simulations. The shapes of the scraps and blanks and the relationship between the punch displacement and the punch force calculated by the simulation agree fairly with those obtained in the experiment.