The University of British Columbia, Vancouver, Canada
Coupling atomistic simulations to phase field modelling of microstructure evolution
The aim of this work is to propose a rigorous approach to connect atomistic scale simulation data to phase field modelling of microstructure evolution. In particular, energy landscapes of solutes at grain boundaries obtained from density functional theory are translated into solute drag pressures for grain boundary migration using the Cahn-Stüwe jump model. The methodology is presented and validated in detail for grain boundary migration in a Au bi-crystal with Bi impurities for which experimental data are available. The proposed approach is then used to describe grain growth in Fe-based alloys. In this context, the potential role of interfacial anisotropies is discussed as well. Further, the extension of the method to migration of phase interfaces, e.g. fcc-bcc in Fe-alloys, is critically analyzed. An outlook on future work will be presented highlighting the challenges to obtain reliable data for interfacial mobilities and interfacial solute diffusion.