Effect of Grain Size Distribution on the Local Mechanical Behavior of Nanocrystalline Materials

A theoretical model based on self-consistent approximation is proposed to explore the effect of grain size distribution on the local mechanical response of nanocrystalline (nc) materials. The representative volume element (RVE) is composed of grains randomly distributed with a grain size distribution following a log-normal statistical function. The grain interior and grain boundary are taken as an integral object to sustain deformation mechanisms of grain-boundary sliding, grain-boundary diffusion and grain-interior plasticity. Local plastic strains and internal stresses, developing within the RVE, have been recorded and discussed.