Line Dislocation Dynamics Simulations with Complex Physics

Abstract

Discrete dislocation dynamics (DDD) simulations provide a technique for examining the effects of fundamental dislocation physics on the plastic response of crystalline solids. Many DDD simulations focus on relatively “simple” materials and loading conditions, such as glide-motion-dominated plasticity of pure cubic crystals. The goal of this chapter is to provide an overview of the more “complex” physical aspects of dislocation-mediated plasticity in the context of DDD. We consider both physics that are intrinsic to the crystal lattice (elastic anisotropy, nonlinear drag, and low crystallographic symmetry) and extrinsic physics that are due to defects other than dislocations (solutes, vacancies, precipitates, and grain boundaries). For each of these classes of physics, we first discuss the conditions under which they are relevant, followed by an examination of the fundamental ways in which the behaviors of dislocations are affected by the physics, and finally a presentation of the methods that have been developed for incorporating the physics in DDD. We end the chapter by discussing three example simulations where complex physics are consequential.