|About this Abstract
||2017 TMS Annual Meeting & Exhibition
||Deformation and Transitions at Interfaces
||The Development of Physically Based Atomistic Microstructure: The Effect on the Mechanical Response of Polycrystals
||Jacob Gruber, Fadi Abdeljawad, Hojun Lim, Stephen Foiles, Garritt Tucker
|On-Site Speaker (Planned)
Molecular dynamics methods are commonly used to study the properties of nanocrystalline systems, usually constructed using Voronoi tessellation methods. In this work, a new method for the generation of atomistic realizations of polycrystalline aggregates from a phase field is presented. The topological properties of generated microstructures are computed and directly compared to structures constructed using Poisson Voronoi tessellation. While there is little difference in the macroscale mechanical response between the two microstructures, substantial differences in the operative deformation mechanisms under uniaxial loading are observed. The results demonstrate that microstructures generated from phase field exhibit a propensity toward dislocation plasticity while those generated from Poisson Voronoi favor grain-boundary mediated mechanisms. These differences suggest that grain topology and grain boundary character significantly affect local responses of polycrystals and that careful consideration of these interface effects is required when attempting to quantify the transition from dislocation-mediated plasticity to interfacial-mediated plasticity in nanocrystalline systems.