An extended vertex and crystal plasticity framework for efficient multiscale modeling of polycrystalline materials

A multiscale modeling framework for polycrystal materials is established, using a combination of an extended vertex model and a crystal plasticity formulation. The 2D vertex model is cast to incorporate a range of mesoscale processes such as grain structure evolution and the influence of second-phase particles. It is combined with a finite strain crystal plasticity formulation whereby also texture development and stored energy accumulation is traced. Computational efficiency is enhanced by GPU-parallelization. The full model captures a wide range of microstructure processes such as dynamic recrystallization, grain growth, texture evolution, anisotropic grain boundary properties as well as particle pinning effects. The macroscale material behavior is directly coupled to the evolving microstructure, for example in terms of a grain size dependent flow stress behavior. Illustrative numerical examples are provided to show the capabilities of the model. For example, the interplay between particle strengthening and grain size influence on macroscopic flow stress behavior is shown, as well as effects due to dynamic recrystallization. Special attention is given to the formulation of the vertex model as the combination of stored energy, particle pinning and anisotropic grain boundary properties give rise to intricate topological transformations which have not been previously addressed.