Coupled atomistic/discrete dislocation method in 3D Part II: Validation of the method

A methodology for coupling a fully atomistic domain to a surrounding domain described by discrete dislocation plasticity, including the treatment of hybrid dislocation lines that span between the two domains, was presented in the first paper of this series [2]. Here, key features of the methodology are assessed quantitatively within a quasi-static framework at 0 K. To avoid solving an expensive but standard complementary problem for the atomistic/continuum coupling of mechanical fields, which is not essential to the key features of the method, a simplified model for obtaining accurate stress and displacement fields is introduced and validated. The test problem consists of the bow-out of a single dislocation in a semi-periodic box under an applied shear stress, and excellent results are obtained in comparison to fully-atomistic solutions of the same problem.