Distinct relaxation mechanism at room temperature in metallic glass

作者：Yitao Sun, Rui Zhao, Da-Wei Ding, Yanhui Liu, H. Y. Bai, M. Z. Li, Weihua Wang · 发表于：Nature Communications · 年份：2023 · DOI：10.1038/s41467-023-36300-x · 被引用次数：44 · 研究领域：Material Dynamics and Properties、Metallic Glasses and Amorphous Alloys、Theoretical and Computational Physics

How glasses relax at room temperature is still a great challenge for both experimental and simulation studies due to the extremely long relaxation time-scale. Here, by employing a modified molecular dynamics simulation technique, we extend the quantitative measurement of relaxation process of metallic glasses to room temperature. Both energy relaxation and dynamics, at low temperatures, follow a stretched exponential decay with a characteristic stretching exponent β = 3/7, which is distinct from that of supercooled liquid. Such aging dynamics originates from the release of energy, an intrinsic nature of out-of-equilibrium system, and manifests itself as the elimination of defects through localized atomic strains. This finding is also supported by long-time stress-relaxation experiments of various metallic glasses, confirming its validity and universality. Here, we show that the distinct relaxation mechanism can be regarded as a direct indicator of glass transition from a dynamic perspective.