Rejuvenation of a deformed metallic glass dominated by immature shear band zones during cryogenic thermal cycling

Cryogenic thermal cycling (CTC) treatment is a promising technique to rejuvenate metallic glasses (MGs), but whose effect is usually highly dependent on the original structure. Spanning shear bands and nonspanning shear bands in deformed MGs not only have different structures, but also are situated in different strain fields, so their responses to CTC are expected to be different. In the present work, the structure, energy state, and property evolutions of the spanning and nonspanning shear bands in deformed MGs during the CTC process were investigated by experiments and molecular dynamics simulations. It was found that CTC increased the proportion of atoms with inelastic strain and induced a rejuvenation in the immature shear band zones that nevertheless led a relaxation in the mature shear band zones. This work not only deepens the understanding of the rejuvenation mechanism of deformed MGs, but also provides a unique perspective for improving their mechanical properties.