Ductile damage analysis of sheet metal forming

This work shows the feasibility of using the concept of continuous damage in the prediction of the admissible deformations in sheet metal forming processes. A constitutive law of elastoplasticity coupled with isotropic damage, derived from the thermodynamic theory of the irreversible processes, and a degenerate shell element are adopted to analyze this forming process. The total Lagrangian formulation and virtual work theory are used to derive the stiffness equation and the relations between displacements and strains. Finally, a three-dimensional contact algorithm permits to impose the restrictions by the tool to the plastic flow. An industrial application example allows to illustrate the described methodology.