Zhang Meng, Chen Yan, Dai Lan-Hong
Institute of Advanced Wear & Corrosion Resistant and Functional Materials, Jinan University, Guangzhou 510632, China.
State Key Laboratory of Nonlinear Mechanics, Institute of Mechanics, Chinese Academy of Sciences, Beijing 100190, China.
J Phys Chem B. 2021 Apr 8;125(13):3419-3425. doi: 10.1021/acs.jpcb.1c00034. Epub 2021 Mar 25.
The essential query about glass formation is how to understand the sheer temperature dependence of viscous dynamics of glass-forming liquids near the liquid-to-glass-transition temperature . In this work, we report a universal scaling in the temperature-dependent viscous dynamics of metallic glasses (MGs) in the form of the Williams-Landel-Ferry equation on the basis of compiled data on the temperature-dependent viscosity and structural relaxation times of 89 MGs ever-reported in the past decades. Implications of this universal scaling are illustrated in the framework of the Adam-Gibbs relation, suggesting a universal vitrification mechanism in MGs mediated by configurational entropy wherein configurational entropy vanishes universally for all supercooled metallic liquids after a further decrease in temperature of ∼170.7 K (whereas with a relatively large error of ±150 K) below . This result corroborates the thermodynamic origin of glass formation and suggests that MGs are an ideal research subject for understanding in depth the nature of glass transition for their relatively simple molecular structures.
关于玻璃形成的关键问题是如何理解在液-玻璃转变温度附近玻璃形成液体粘性动力学对温度的强烈依赖性。在这项工作中，我们基于过去几十年报道的89种金属玻璃（MGs）的温度依赖性粘度和结构弛豫时间的汇编数据，以威廉姆斯-兰德尔-费里方程的形式报告了金属玻璃温度依赖性粘性动力学中的一种通用标度关系。这种通用标度关系的意义在亚当-吉布斯关系的框架中得到了说明，这表明在金属玻璃中存在一种由构型熵介导的通用玻璃化机制，其中在温度进一步降低约170.7 K（误差相对较大，为±150 K）后，所有过冷金属液体的构型熵普遍消失。这一结果证实了玻璃形成的热力学起源，并表明金属玻璃因其相对简单的分子结构，是深入理解玻璃转变本质的理想研究对象。
