Modeling and Simulation of Thin Sheet Blanking using damage and rupture criteria

Because of the trend in the industry to smaller sheet thickness and higher stroke rates, modeling of blanking requires the development of advanced material models. Large plastic strain, high strain rate effects, adiabatic heating and the associated temperature effects, as well as damage and rupture have to be taken into account. In this study, two material models are considered: a physically based model for plasticity (MTS model) combined with a Nucleation And Growth (NAG) model for damage and failure and a phenomenological model for both plasticity and failure (Johnson and Cook, 1985). Finite Element predictions with both models are compared with experimental results and discussed. RESUME. La tendance actuelle dans l'industrie conduit a decouper des toles de plus en plus minces, a des cadences de plus en plus elevees. Ceci requiert le developpement de modeles avances, capables de prendre en compte les effets des grandes deformations, des grandes vitesses de deformation et de l'endommagement jusqu'a rupture. Adiabaticite et effets de temperature associes sont aussi a prendre en compte. Dans cette contribution, nous considerons deux modeles : un modele mecanistique de plasticite, le modele MTS, combine a un modele de nucleation et croissance de cavites (modele NAG) d'une part et le modele phenomenologique de Johnson-Cook (Johnson et Cook, 1985) d'autre part. Les resultats de simulations numeriques de la decoupe utilisant ces deux modeles sont compares avec l'experience et discutes.