Shear transformation zones structure characterization in Cu50Zr50 metallic glasses under tensile test

Abstract

The atomic structure of Cu50Zr50 metallic glasses under tensile test was investigated using molecular dynamics simulations. Voronoi polyhedra analysis was employed to calculate the number of neighbors for each atom, obtained as the total number of faces of the polyhedron, in order to inspect their relationship with plasticity. An inspection based on the atoms that contribute to shear transformation zones revealed that Cu atoms with 12 neighbors played the main role during the plastic regime. During the onset of plasticity, it was observed that the population of Cu species with initially 12 neighbors, denoted as Cu12, increased their number of neighbors to 13 and 14. Then, during the softening of the sample, the population of Cu12 decreased, equaling the population of Cu13 at 0.11 strain onwards. We hope that these results can help to further unveil the structure transformation driven by shear transformation zones nucleation in metallic glasses.