Numerical implementation of a recent improved Gurson-type model and application to ductile fracture

The present study is based on a recent work by Monchiet et al. [V. Monchiet, E. Charkaluk, D. Kondo, Comptes Rendus-Mecanique, 335 (2007) 32–41] (see also [V. Monchiet, Contributions à la modélisation micromécanique de l’endommagement et de la fatigue des métaux ductiles, PhD thesis, Université des sciences et Technologies de LILLE, France, 2006]) who formulated an improved Gurson-type approximate criterion of ductile porous media by considering trial velocity fields inspired from the solution of the Eshelby inhomogeneous inclusion problem. We first briefly present the methodology allowing to derive this new criterion and illustrate its advantages compare to existing criteria. Then we present the formulation of a constitutive plastic-damage model associated to this new criterion. Finally, this new model is implemented in a Finite Element software and applied to the study of a round tensile specimen and a notched sample. The obtained results are discussed by comparing them to those given by existing models.