Molecular dynamics simulations show significant differences in the deformation mechanisms of nanocrystalline Ni with low- and high-angle boundaries. For the case studied with average grain size of 12nm, low-angle boundaries present enhanced dislocation activity and reduced strength with respect to high-angle boundaries for low strains. In the latter, most of the deformation was accommodated at the grain boundaries with limited dislocation activity, while in the case of low-angle boundaries, most of the displacements observed were associated with the motion of partial dislocations nucleated at the grain boundaries.

Differences in Deformation Processes in Nanocrystalline Nickel with Low- and High-Angle Boundaries from Atomistic Simulations. M.J.Caturla, T.G.Nieh, J.S.Stolken: Applied Physics Letters, 2004, 84[4], 598-600