Dislocation Patterns in Crystalline Solids—Phenomenology and Modelling

This chapter provides an overview of the dislocation patterning phenomena in metals and semiconductors and their modeling using dislocation dynamics approaches. The plastic displacements occur by shifting the adjacent lattice planes against each other by a lattice vector. As the crystalline solids deform plastically, the expansion of the slipped areas leads to an increase in the dislocation line length within the crystal, known as the "dislocation multiplication." Such proliferation of dislocations goes along with their spatial re-distribution, and more often with the formation of heterogeneous dislocation patterns. The characteristics of such patterns depend on the material properties and deformation conditions. From a dynamical point of view, distinguishing the glide motion of a dislocation line within its slip plane from out-of-plane "climb" motions is important. The out-of-plane "climb" motions take place by inserting or removing material, and therefore dislocation climb is possible only at temperatures where long-range self-diffusion can occur.