Using the finite cell method to predict ductile damage with crack closure effect

In this paper, the Finite Cell Method (FCM) is used to predict the ductile damage and crack evolution in ductile materials under small strains and nonlinear isotropic hardening conditions. In the first step, a fully coupled elastic-plastic-damage model based on modified Lemaitre ductile damage model was developed and implemented into FCM implicit codes. Also the effect of micro-crack closure, which may dramatically decrease the rate of damage growth under compression, was incorporated and its computational implementation was discussed. The FCM is the result of combining the p-version finite element and fictitious domain methods, and has been shown to be effective in solving problems with complicated geometries for which the meshing procedure can be quite expensive. It, therefore, combines fast and simple mesh generation with a high convergence rate inherited from p-FEM. The performance of the FCM and damage model is verified by means of numerical examples and the results were compared with exprimental observation. The results showed that modified Lemaitre damage model can be used as a quick and accurate tool to predict ductile damage and fracture in metal forming processes.