Modelling of ductile failure in metal forming

Damage and fracture are important criteria in the design of products and processes. Damage mod- els can be used to predict ductile failure in metal forming processes. Nonlocal models avoid the mesh dependency problems of local damage models. A nonlocal damage model has been implemented in LS- DYNA using the user-subroutines UMAT and UCTRL1. The implemented model will be compared with results obtained with the available option in LS-DYNA to combine *MAT PLASTICITY WITH DAMAGE with *MAT NONLOCAL. Advantages and disadvantages of the different implementations will be dis- cussed. The user nonlocal damage model has been applied to a bending and a blanking process. Results of these simulations will be shown.