Plasticity and damage with gradient enhancement: A review of application to high speed forming

Abstract

Efficiency, durability and lightweight are key aspects in designing new products such as cars or other machines. However, when materials are processed by plastic forming, one has to consider the forming limits of the materials which indicate the starting point for localization or fracture of the material. High speed forming processes, such as electro-magnetic forming offer a possibility to widen these limits. Since standard plasticity models do not account for the damage behavior at these high strain rates, a new model of coupled damage-plasticity at high strains and high strain rates has to be developed. When damage occurs, one may have to deal with a mechanism called localization, which leads to non-physical solutions. One way to deal with this problem is to introduce a gradient enhanced damage model. In this paper, a gradient enhanced elasto-plastic model was developed and tested on some academic examples such as notched beams.