Micromechanics Modeling of Fracture in Nanocrystalline Metals

摘要

Nanocrystalline metals have very high theoretical strength, but suffer from a lack of ductility and toughness. Therefore, it is critical to understand the mechanisms of deformation and fracture of these materials before their full potential can be achieved. Because classical fracture mechanics is based on the comparison of computed fracture parameters, such as stress intensity factors, to their empirically determined critical values, it does not adequately describe the fundamental physics of fracture required to predict the behavior of nanocrystalline metals. Thus, micromechanics-based techniques must be considered to quantify the physical processes of deformation and fracture within nanocrystalline metals. This paper discusses fundamental physics-based modeling strategies that may be useful for the prediction of deformation, crack formation and crack growth within nanocrystalline metals.