A refined local structure in a metallic glass tailored via flash-annealing

Due to rapidly quenching, metallic glasses (MGs) usually are metastable, which indicates that the microstructure of MGs can be easily manipulated by external energies. In the present study, a flash-annealing technique is used to influence the structure behavior of a Zr-based MG, which causes a structurally relaxation and/or rejuvenation via temperature changing. The structures at different length scales as well as the mechanical properties are examined. An auto-correlation function analysis based on transmission electron microscopy images, and a high energy synchrotron X-ray diffraction technique are used to characterize the structural evolution of flash-annealed MGs on the nano-scale and on the atomic-scale. The results demonstrate that crystal-like-ordering (CLO) regions play a key role to dominate the relaxation and the rejuvenation processes. The rejuvenation leads to short-range orders that are loosely-packing connections within a medium-range order, which reduces structural order and causes a high configurational energy state. An opposite behavior occurs in the relaxed MG. The rejuvenation induces an obviously low density, elastic modulus and shear modulus in the macroscopic performances of the MG. The findings highlight the fact that the quantitative manipulation of the amount of CLO regions can be achieved via flash-annealing, which can modify the mechanical behavior of the MG.