[Download]Name: Wang C, Yang Z Z, Ma T, et al. High stored energy of metallic glasses induced by high pressure[J]. Applied Physics Letters, 2017, 110(11): 111901.

Class: 2017

Content:
Modulating energy states of metallic glasses (MGs) is significant in understanding the nature of
glasses and controlling their properties. In this study, we show that high stored energy can be
achieved and preserved in bulk MGs by high pressure (HP) annealing, which is a controllable
method to continuously alter the energy states of MGs. Contrary to the decrease in enthalpy by
conventional annealing at ambient pressure, high stored energy can occur and be enhanced by
increasing both annealing temperature and pressure. By using double aberration corrected scanning
transmission electron microscopy, it is revealed that the preserved high energy, which is attributed
to the coupling effect of high pressure and high temperature, originates from the microstructural
change that involves “negative flow units” with a higher atomic packing density compared to that
of the elastic matrix of MGs. The results demonstrate that HP-annealing is an effective way to activate
MGs into higher energy states, and it may assist in understanding the microstructural origin of
high energy states in MGs.