Theoretical Models of Dislocation Emission from Grain Boundaries in Deformed Nanocrystalline Materials

An overview of theoretical models of dislocation emission from grain boundaries in nanocrystalline materials under plastic deformation is presented. It is shown that grain boundaries can serve as effective alternative sources of mobile dislocations when the standard dislocation sources are suppressed. The discussed dislocation emission mechanisms are responsible for some specific, experimentally observed features of plastic deformation in nanocrystalline materials.