RESOLVING DEFORMATION MODES OF NANOCRYSTALLINE METALS USING CONTINUUM METRICS BASED ON ATOMISTIC SIMULATIONS

Deformation processes in nanocrystalline (NC) metals such as dislocation nucleation/absorption and grain boundary shuffling/sliding are mediated at interfaces. Grain boundaries and their junctions fundamentally control NC material inelastic deformation mechanisms. However, material deformation is inherently multiscale and quantifying failure criteria and scaling relations across multiple length/time scales has proven to be difficult. We apply recently developed volume-averaged kinematic variables from continuum mechanics as metrics to assess results of atomistic simulations. These metrics are computed using nearest neighbors and include kinematic quantities such as microrotation and dilatation. Useful insight into the origins of plastic deformation in NC metals is gained by their application, enabling resolution