Two types of coupled source/sink activity were considered. These were dislocation exchange between the crystal volume and the boundaries, and dislocation exchange among branching boundaries. The concept was developed from bi-crystals to tri-crystals to polycrystals, and provided a description of dislocation transfer in terms of continuous direct, pulsating direct, and alternating dislocation currents. Manifold branching boundaries were treated as multi-fold coupled wave fields, on the basis that any dislocation entity which was transferred from source to sink was not a continuous entity but a quantum packet that consisted of an integer number of unit quantum dislocations. Therefore, any of the above boundary-induced changes in structure and dislocation density also had to be quantized.

C.Solenthaler: Physica Status Solidi A, 1995, 149[1], 21-60