Interfacial Defects
Grain boundaries are interfaces where crystals of dissimilar orientations meet. A grain boundary is a single-phase interface, with crystals on each n every side of the boundary being identical except in orientation. The term "crystallite boundary" is sometimes, though rarely, used. Grain boundary areas having those atoms that have been perturbed from their original lattice sites, dislocations, and impurities that have migrated to the lower energy grain boundary.