Stress-induced mechanical heterogeneity in metallic glasses revealed by spatial nano-indentation

The heterogeneity plays a key role in physical and mechanical properties of a material. The nature of lacking long-range order in metallic glasses (MGs) causes the local atomic rearrangement to vary significantly in space when compressed. Different configurations of an ensemble of atoms in a MG lead, therefore, to a distribution of nanohardness, which also changes in space. The effects of pressure on the mechanical heterogeneity of MGs induced by a stress have been investigated by spatial nanoindentation. The mechanical heterogeneity is quantified by calculating shear-transformation zone volumes. Here, we demonstrate that the spatial nanohardness experimentally reveals very well on pressure-induced local mechanical heterogeneity in MGs.