In nanocrystalline materials, the misfit of lattice structures at the junctions of grain boundaries generally increased local stresses that could be released by grain boundary sliding. Here, the sliding behaviors of the ordered Σ = 3 (111) grain boundary (twin) and Σ = 11 (113) grain boundary in nanocrystalline palladium were investigated by means of high-resolution transmission electron microscopic observations and molecular statics calculations. It was found that the twin boundary could release either large stresses by sliding with a DSC-lattice vector, or release small stresses by sliding over an imperfect vector. The observed Σ = 11 grain boundary image was exactly symmetrical, from which no grain boundary sliding along the [332] direction could be clearly identified, but another sliding component direction could not be determined. The image simulations indicated that the latter was experimentally unidentifiable.

The Potential for Ordered Grain Boundary Sliding in Nanocrystalline Palladium. Y.C.Wang, D.H.Ping, D.X.Li: Philosophical Magazine Letters, 2008, 88[5], 343-51