Thickness of shear bands in metallic glasses

A review of measurements and atomistic modeling shows that shear bands in metallic glasses have a characteristic thickness of ∼10nm. Such extreme localization of plastic deformation, within a thicker liquidlike layer implied by fracture-surface morphology, cannot have a thermal origin. By analogy with granular materials, the thickness is linked to the local structural rearrangements required to generate dilatation. This analysis suggests that first-coordination-shell clusters may be significant structural units in metallic glasses.