The Nonlocal Continuum Theory of Lattice Defects

Abstract

Crystal imperfections, like those of human beings, come in seemingly endless variety. However, not all are equally interesting or easy to deal with. In these lectures we restrict ourselves to the most important kinds such as point defects and dislocations. Their presence has a profound effect on the physical properties of the material. Examples of point defects are vacancies and interstitials which are point defects consisting of the absence of an atom or the presence of an extra atom (Fig. 1). Dislocations, on the other hand, are line defects consisting of, for instance, an extra plane of atoms ending inside the crystal (edge dislocation, Fig. 2).