Molecular dynamics methods were used to study the mechanical response under shear of two Cu systems containing symmetrical tilt and twist grain boundaries, respectively. The investigation focused on the mechanism of localized atomic displacements during plastic deformation. It was shown that grain boundary sliding generates a perturbed layer of atomic species, with thickness increasing approximately with the square root of time. The dynamics of the atomic displacement processes, even though apparently stochastic, was intimately connected with the local density experienced by atoms under shear.

Dynamics of Atomic Species Involved in Shear-Induced Displacements at Sliding Symmetrical Grain Boundaries - a Numerical Study. F.Delogu: Journal of Physics - Condensed Matter, 2007, 19[9], 096008 (14pp)