Schawe Jürgen E K, Kwak Min Kyung, Stoica Mihai, Park Eun Soo, Löffler Jörg F
Laboratory of Metal Physics and Technology, Department of Materials, ETH Zurich, 8093 Zurich, Switzerland.
Department of Materials Science and Engineering, Research Institute of Advanced Materials & Institute of Engineering Research, Seoul National University, Seoul 08826, Republic of Korea.
J Phys Chem Lett. 2025 Jan 30;16(4):948-954. doi: 10.1021/acs.jpclett.4c03275. Epub 2025 Jan 21.
The behavior of supercooled glass-forming metals depends on the cooperative atomic fluctuations caused by dynamic heterogeneities in the melt. These spatial and temporal heterogeneities form dynamic clusters, which are regions of cooperative rearrangement (CRR). In this study, the macroscopic kinetics and the correlation length , of the CRR, are derived for PtCuNiP and PdCuNiP metallic glass-formers by fast differential scanning calorimetry near the glass transition. While the alloy composition influences the α-relaxation and vitrification kinetics, typically defined by the glass transition, as well as the limiting temperature of the Vogel-Fulcher-Tammann-Hesse equation and the fragility index, it has no significant influence on the correlation length of the cooperative atomic motions. In agreement with many other materials, is about 3 nm at the glass transition for both metallic glasses. The temperature dependence of correlates with the apparent activation energy of the α-relaxation and is the reason for its non-Arrhenius behavior.
过冷玻璃形成金属的行为取决于熔体中动态不均匀性引起的协同原子涨落。这些空间和时间上的不均匀性形成了动态团簇，即协同重排区域（CRR）。在本研究中，通过在玻璃化转变温度附近的快速差示扫描量热法，推导了PtCuNiP和PdCuNiP金属玻璃形成体的宏观动力学以及CRR的相关长度。虽然合金成分会影响通常由玻璃化转变定义的α弛豫和玻璃化动力学，以及Vogel-Fulcher-Tammann-Hesse方程的极限温度和脆性指数，但它对协同原子运动的相关长度没有显著影响。与许多其他材料一致，两种金属玻璃在玻璃化转变时的相关长度约为3 nm。相关长度的温度依赖性与α弛豫的表观活化能相关，这也是其非阿累尼乌斯行为的原因。
