Modeling of plasticity and ductile fracture physical mechanisms and numerical simulation of laboratory specimens

Gilles Rousselier (1)

1 CDM - Centre des Matériaux

The most commonly observed ductile fracture mechanism is void nucleation, growth and coalescence. Fully coupled "porous plasticity" models (GTN, Rousselier) are presented and their limits are discussed in relation with quantitative observations and micromechanical simulations. Strain localization in a macroscopic planar band represents the void coalescence phase. (Micromechanical modeling of nucleation is not presented.) These models are well suited for laboratory specimen calculations, including the multi-scale version with a reasonable computation time due to reduced texture identification (8 to 15 crystal orientations). A trans-granular crystallographic ductile fracture mechanism is also modeled in the multi-scale framework. Examples of numerical simulations are given for aluminum and steel specimens. The experimental and numerical results are in good agreement with regard to fracture strains and locations as well as macroscopic/microscopic features. The effect of the carbides-nucleated secondary population of voids in low alloyed steels is modeled in the multi-scale framework and used in calculations.

Mots clés: porous plasticity; strain localization; Coulomb-Rousselier ductile fracture model; submicron voids; finite elements

Domaines: Sciences de l'ingénieur [physics]

Gilles Rousselier. Modeling of plasticity and ductile fracture physical mechanisms and numerical simulation of laboratory specimens. 24ème Congrès Français de Mécanique, Aug 2019, Brest, France. ⟨hal-02401455⟩