The mechanism of formation of fragmented (banded, block) dislocation structures in crystals subjected to large plastic deformations were discussed. The theoretical analysis was based upon the kinetic equations for the density of geometrically necessary dislocations. The equations include the processes of multiplication, immobilization, annihilation, and diffusion of geometrically necessary dislocations. The formation of an fragmented dislocation structures was considered a synergetic process of self-organization of geometrically necessary dislocations obeying the principle of similitude of dislocation structures at various degrees of plastic deformation. Conditions for the formation of the structures at hand were determined, as well as their parameters and the dependence of these parameters on the degree of deformation. The theoretical results were compared with the available experimental data.

Kinetic Mechanism of the Formation of Fragmented Dislocation Structures upon Large Plastic Deformations. G.A.Malygin: Physics of the Solid State, 2002, 44[11], 2072-9