The tensile strength of a metallic bicrystalline nanofilm, containing a wedge disclination in the middle of a grain boundary terminating at the film surface, was studied using atomistic simulations. The results showed that an increase in the disclination-power strengthened the film if a crack initiated at one end of the terminated grain boundary, whereas it weakened the film if a crack initiated at the disclination core. Both the strengthening and weakening phenomena exhibuted a size-effect for film thicknesses of 10 to 20nm, and were markedly affected by the grain-boundary misorientation. It was further shown that the strength could be increased to ∼80% of the theoretical strength of a defect-free film by introducing a disclination of moderate power into the grain boundary.

Atomistic Simulations of the Tensile Strength of a Disclinated Bicrystalline Nanofilm. K.Zhou, A.A.Nazarov, M.S.Wu: Philosophical Magazine, 2008, 88[27], 3181-91