Elastic interactions between interface dislocations and internal stresses in finite-thickness nanolayered materials

Abstract

Anisotropic elasticity theory is used to analyze elastic strain interactions between heterophase interface dislocations and four types of internal stresses in finite-thickness nanolayered face-centered cubic materials. The first interaction is related to the mechanical forces acting on semicoherent interfaces, which arise from heterogeneous elastic fields between the neighboring materials with free surfaces. The second interaction is associated with the Peach-Koehler force exerted on lattice dislocations in free-standing bi- and tri-nanolayers, and is compared to the limiting case of infinite bicrystals. The third case yields to the interaction energy balance and the corresponding equilibrium distance between two Shockley partial dislocations. The fourth and last case is dedicated to the elastic interaction forces between vacancies and interfaces using the force dipole moment approximation.For such cases, the elastic interaction problems are treated by involving the effects of (i) the dislocation characters, (ii) the anisotropic (versus isotropic) elasticity calculations, and (iii) the additional third coherent MgO layer on bilayered Au/Al systems.