The DigiMat Project
EU-NSF coordinated activities in computational materials research

No generic model is currently available to describe the recrystallization behavior of a wide class of metallic alloys. This is due in great measure to the fact that recrystallization, like many similar state-altering processes that are driven by thermal energy and internal energy of structural defects, really is controlled by factors at several length scales. Multiscale modelling is thus a requisite to coming to a full (and quantitative) understanding of recrytallization.

We propose to organize a modelling effort centered around a digital material framework. This framework is based on a digital representation of the material structure, where data coming from different scales can be stored or probed. The digital representation can be converted into finite element meshes, which are then used to simulate plastic deformation and subsequent recrystallization. The local behavior of individual microstructure components is computed through models operating at different scales. In particular, grain constitutive models are derived from the modelling of dislocation populations within the grains, and grain boundary motion is described by connecting the continuum mechanical and thermal fields to simulations at the atomistic and dislocations levels. A detailed confrontation of the multiscale approach with experiment will be done at the ESRF synchrotron facility in Grenoble (France), where 3D mapping of grain structures is now possible, together with the analysis of high resolution diffraction peaks.