Mini-symposium title
1-6 - Multiscale Modelling of Polycrystalline Materials
Javier Segurado (Universidad Politécnica de Madrid), Ricardo A. Lebensohn (Los Alamos National Laboratory)
Mini-symposium description

The mechanical response of polycrystalline materials depends on the crystal behaviour and the material’s microstructure. Concerning the former, plastic deformation is controlled by dislocation nucleation, movement and interactions, and other mechanisms as the formation and evolution of twins, diffusion, etc., and can be modelled using discrete models (molecular mechanics) or continuum models (dislocation dynamics, crystal plasticity). The polycrystal’s microstructure also has a deep influence in the macroscopic response and can be described by the grain size, shape and orientation distributions, and by the character of the grain boundaries that control the interactions between adjacent grains. A realistic, microstructure-based description of the polycrystal’s macroscopic behaviour needs to incorporate models for the deformation mechanisms at single crystal level, and integrate them to provide the macroscopic response, by using some kind of multiscale methodology.

This symposium focuses on recent advances in model and simulation techniques to predict microstructure-dependent mechanical properties of polycrystalline aggregates. The main topics are:

- Semi-analytical models representing microstructure-sensitive properties of polycrystals: plastic anisotropy, tension-compression asymmetry, complex (e.g. anisotropic, kinematic) hardening behavior, dilatational plasticity due to the presence of voids, etc.

- Mean-field/homogenization-based crystal plasticity models to represent the micromechanical response of polycrystalline materials, including the aforementioned microstructural effects.

- Full-field/computational homogenization models for polycrystals: crystal plasticity FEM, Fast Fourier Transforms (FFT)-based methods, including higher-order plasticity theories.

- Discrete dislocation dynamics, including treatment of single-crystal elastic anisotropy and heterogeneity (polycrystallinity, grain boundaries, precipitates, free surfaces).

- Hierarchical models for the multiscale modeling of polycrystals, including combination of the previous approaches.

- Concurrent (embedded) multiscale methods linking different scales in polycrystalline materials.