The kinetics of relaxation of disclination quadrupoles formed within triple junctions of grains during plastic deformation were studied. The calculations were made by using the discrete dislocation model for disclinations by simulating the climb of dislocations. Exponential relationships were obtained for the relaxation of the strength and elastic energy of disclination quadrupoles with a characteristic time proportional to the cube of grain size. The distribution of vacancy fluxes along grain boundaries during the relaxation of a disclination quadrupole was studied in detail. The relation between continuum and discrete dislocation approaches to a study of the grain boundary recovery process was considered. Characteristics of each relaxation stage were studied. A hierarchy of characteristic relaxation times for different grain size ranges was constructed and it was shown that in nanocrystalline materials the spreading time of trapped lattice dislocations could depend upon the grain size.

On the Annealing of Junction Disclinations in Deformed Polycrystals. D.V.Bachurin, A.A.Nazarov: Philosophical Magazine A, 2003, 83[23], 2653-67