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 (Anciaux et al., 2017). 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.