Yang Qun, Wei Shuai, Yu Yang, Zhang Hui-Ru, Gao Liang, Bu Qing-Zhou, Amini Narges, Cheng Yu-Dong, Yang Fan, Schoekel Alexander, Yu Hai-Bin
Wuhan National High Magnetic Field Center and School of Physics, Huazhong University of Science and Technology, Wuhan 430074, Hubei, China.
Department of Chemistry, Aarhus University, 8000 Aarhus, Denmark.
J Chem Phys. 2022 Nov 14;157(18):184504. doi: 10.1063/5.0123202.
Establishing the structure-property relationship is an important goal of glassy materials, but it is usually impeded by their disordered structure and non-equilibrium nature. Recent studies have illustrated that secondary (β) relaxation is closely correlated with several properties in a range of glassy materials. However, it has been challenging to identify the pertinent structural features that govern it. In this work, we show that the so-called polyamorphous transition in metallic glasses offers an opportunity to distinguish the structural length scale of β relaxation. We find that, while the glass transition temperature and medium-range orders (MROs) change rapidly across the polyamorphous transition, the intensity of β relaxation and the short-range orders (SROs) evolve in a way similar to those in an ordinary reference glass without polyamorphous transition. Our findings suggest that the MRO accounts mainly for the global stiffening of the materials and the glass transition, while the SRO contributes more to β relaxation per se.
建立结构-性能关系是玻璃态材料的一个重要目标，但这通常会受到其无序结构和非平衡性质的阻碍。最近的研究表明，次级（β）弛豫与一系列玻璃态材料的多种性能密切相关。然而，确定控制它的相关结构特征一直具有挑战性。在这项工作中，我们表明金属玻璃中所谓的多晶转变为区分β弛豫的结构长度尺度提供了一个机会。我们发现，虽然玻璃转变温度和中程有序（MROs）在多晶转变过程中变化迅速，但β弛豫强度和短程有序（SROs）的演化方式与没有多晶转变的普通参考玻璃相似。我们的研究结果表明，MRO主要影响材料的整体硬化和玻璃转变，而SRO对β弛豫本身的贡献更大。
