Despite that metallic glasses are among the most studied metallic materials, still very little is known on the evolution of their unique structural, dynamical and elastic properties under compression, owing to the difficulty to perform in-situ high pressure experiments. Coupling the brightest x-rays available in synchrotrons with cutting edge high pressure technologies, we provide direct evidence of the microscopic structural and dynamical mechanisms occurring under in-situ high pressure compression and decompression in the GPa range, from the onset of the perturbation up to a severely-deformed state. We show that while pressure promotes density increasing through quasi-elastic structural deformations, the atomic mobility exhibits a hysteresis and is enhanced up to a factor 15 even at temperatures well below the glass transition. This surprising behavior results from a competition between fast avalanche-like atomic rearrangements and slow relaxation processes triggered by an anomalous super-diffusive collective particle displacement. These results provide new insights on the effect of deformation in non-ergodic materials and support the occurrence of string-like diffusion of liquid-like atoms in metallic glasses. They explain also the macroscopic impressive rejuvenation and strain hardening reported recently under ex-situ densifications.

尽管金属玻璃是研究最多的金属材料之一，但由于难以进行原位高压实验，对其在压缩下独特的结构、动力学和弹性特性的演变仍然知之甚少。将同步加速器中可用的最亮 X 射线与尖端高压技术相结合，我们提供了 GPa 范围内原位高压压缩和减压下发生的微观结构和动力学机制的直接证据，从扰动开始到严重变形的状态。我们表明，虽然压力通过准弹性结构变形促进密度增加，但原子迁移率表现出滞后性，即使在远低于玻璃化转变的温度下也能提高到 15 倍。这种令人惊讶的行为是由快速的类似雪崩的原子重排和由异常超扩散集体粒子位移引发的缓慢弛豫过程之间的竞争引起的。这些结果为非遍历材料中变形的影响提供了新的见解，并支持金属玻璃中液态原子的弦状扩散的发生。他们还解释了最近在非原位致密化下报道的令人印象深刻的宏观再生和应变硬化。这些结果为非遍历材料中变形的影响提供了新的见解，并支持金属玻璃中液态原子的弦状扩散的发生。他们还解释了最近在非原位致密化下报道的令人印象深刻的宏观再生和应变硬化。这些结果为非遍历材料中变形的影响提供了新的见解，并支持金属玻璃中液态原子的弦状扩散的发生。他们还解释了最近在非原位致密化下报道的令人印象深刻的宏观再生和应变硬化。