Atomistic study of Eshelby's inclusion and inhomogeneity problems in a model bcc crystal

Abstract

Finnis–Sinclair N-body potentials for alloy systems comprised of W and generic materials having various degrees of lattice misfit or modulus misfit to W are developed for subsequent studies of the influence of these precipitate–matrix property misfits on the interaction between precipitates and lattice defects or dislocations. In this work, molecular statics simulations employing the constructed potentials are carried out to investigate elastic states of the isotropic media containing the coherent misfit spherical precipitates. The results obtained are juxtaposed with equivalent Eshelby's inclusion and inhomogeneity solutions derived from elasticity theory to evaluate agreements between the two methods and the performance of the potentials. The results show that atomistic simulations yield good agreement with continuum models. For the case of precipitate with lattice misfit, agreement between the two approaches can be improved by taking into account the precipitate–matrix interface effect. Deviation between the two methods is also observed when the elastic modulus misfit precipitate becomes small in size.