Numerical formulations for nonlocal plasticity problems coupled to damage in the polycrystalline microstructure

Abstract

This paper discusses a mesomechanics behavior of the polycrystalline microstructure, where grains are bonded to each other via interfaces along boundaries. For the mesomechanics description the nonlocal constitutive model is applied. According to this model, distance effects at the mesostructure level, by which some amount of energy is interchanged between material particles within the body, imply that the first principle of thermodynamics is accomplished by a nonlocality residual. The nonlocality residual term takes into account energy exchanges between the material particles promoted by the diffusion process of nonlocality effects.In this paper numerical formulations that are built up on a combined method of contour elements are implemented. Therefore used integration techniques are analytical only for all contour elements. For the grains and interfaces, results of mesomechanical simulations refer to macroscopic predictions, which can be obtained by means of enhanced version of Gurson-type model incorporating effects of a microvoid aspect ratio.