A theoretical model was suggested which describes several types of transformations of grain boundary dislocation pile-ups at triple junctions of grain boundaries in superplastically deformed nanocrystalline and polycrystalline materials. Ranges of parameters of defect configurations were revealed at which the transformations considered were energetically favorable. The role of transformations of grain boundary dislocation pile-ups at triple junctions of grain boundaries in plastic deformation processes in nanocrystalline and polycrystalline materials was considered, with particular regard to the influence of such transformations on competition between different deformation mechanisms in nanocrystalline materials.

Transformations of Grain Boundary Dislocation Pile-Ups in Nano- and Polycrystalline Materials. A.A.Fedorov, M.Y.Gutkin, I.A.Ovidko: Acta Materialia, 2003, 51[4], 887-98