The dynamics of dislocation assemblies in deforming crystals involved the emergence of collective phenomena, intermittent fluctuations and strain avalanches. In polycrystalline materials, the understanding of plastic deformation mechanisms depended upon understanding the role played by grain boundaries in dislocation motion. The interaction of dislocations and elastic low-angle grain boundaries was studied here in the framework of a discrete dislocation representation. Grain boundaries were allowed to deform under the effect of dislocation stress fields, and the effect of such a perturbation was compared to the case of rigid grain boundaries. It was possible to determine analytical and numerical corrections, to dislocation stress fields acting upon neighbouring grains, as mediated by grain-boundary deformation.

Dislocation Interactions Mediated by Grain Boundaries. P.Moretti, L.Laurson, M.J.Alava: Journal of Statistical Mechanics, 2008, P05010