Rejuvenation behavior of Cu-Zr metallic glass under different holding times during deep cryogenic cycling treatment: Experiments and simulation

The rejuvenation behavior of Cu-Zr binary metallic glasses with different holding times in both ambient and cryogenic temperatures during deep cryogenic cycling treatment were investigated in details. The degrees of rejuvenation, the structure and properties were investigated by both experiments and simulation. It is found that the holding times can significantly affect the rejuvenation behavior. The samples with different holding times can be either aged or rejuvenated, that is, the shorter holding times could effectively rejuvenate the samples, while the longer holding times aged the samples. Such phenomenon can be observed from both experimental and simulation results. It is also found that the fraction of liquid-like structure increases while solid-like structure decreases in the short-range ordered structures for those rejuvenated samples, leading to a more heterogeneous structure. Such changes in local atomic structure contributes to the improvement in the mechanical properties, which is related to delocalization of the shearing events and the formation of more shear-transformation zones. The present study contributes to the understanding of the correlation between the treatment parameters during deep cryogenic cycling treatment and the rejuvenation behavior, as well as the structural evolution.