The term polygonization was used originally to describe the situation that occurs when a single crystal is bent to a relatively small radius of curvature and then annealed. Bending result in the introduction of an excess number of dislocations of one sign. These dislocations are distributed along the bent-glide planes as shown in it. When the crystal is heated, the dislocation group themselves into the lower-energy configuration of a low-angle boundary by dislocation climb. The resulting structure is a polygonlike network of low-angle grain boundaries.