Dynamic Mechanical Relaxation in Bulk Metallic Glasses: A Review
Dynamic Mechanical Relaxation in Bulk Metallic Glasses: A Review
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DOI：
10.1016/j.jmst.2014.04.018
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发表时间：
2014-06
影响因子：
10.9
通讯作者：
J. Qiao;J. Pelletier
中科院分区：
文献类型：
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作者：
J. Qiao;J. Pelletier
在过去的几十年里，金属玻璃引起了相当大的兴趣，因为它们表现出迷人的性能。本文首先简要介绍了非晶合金的力学性能、热学性能及其应用。此外，我们还着重研究了金属玻璃的动态力学弛豫行为，即主弛豫（α）和次弛豫（β）。玻璃态材料的力学松弛行为与其力学性能和物理性能密切相关。玻璃态材料中的主要弛豫与玻璃化转变现象和粘性流动有关。另一方面，β弛豫与金属玻璃中的许多基本问题有关。在这些材料中，松弛过程与塑性变形机制直接相关。机械弛豫，特别是β弛豫为设计具有所需物理和机械性能的金属玻璃提供了极好的机会。我们证明了金属玻璃中主驰豫的普遍特征。介绍了描述金属玻璃中主要弛豫的唯象模型和物理理论。同时，我们显示了金属玻璃中的α和β弛豫对热处理的依赖性。最后，我们分析了金属玻璃中原子迁移率与热机械处理之间的相关性。一方面，金属玻璃中的原子迁移率通过物理老化或晶化而降低。另一方面，金属玻璃中的原子迁移率通过变形（即压缩和冷轧）而增强。重要的是，为了分析非晶材料中的原子迁移率，引入了物理理论。这个模型调用了准点缺陷的概念，这对应于玻璃材料中的密度波动。
Metallic glasses have aroused considerable interest in the past decades because they exhibit fascinating properties. First, this article briefly outlines the mechanical, thermal properties and application of the metallic glasses. In addition, we focus on the dynamic mechanical relaxation behaviors, i.e. main (α) and secondary (β) relaxations, in metallic glasses. The mechanical relaxation behaviors are connected to the mechanical properties and physical properties in glassy materials. The main relaxation in glassy materials is related to the glass transition phenomenon and viscous flow. On the other hand, the β relaxation is linked to many fundamental issues in metallic glasses. In these materials relaxation processes are directly related to the plastic deformation mechanism. The mechanical relaxations, particularly, the β relaxation provides an excellent opportunity to design metallic glasses with desired physical and mechanical properties. We demonstrate the universal characteristics of main relaxation in metallic glasses. The phenomenological models and the physical theories are introduced to describe the main relaxation in metallic glasses. In parallel, we show the dependence of the α and β relaxations on the thermal treatments in metallic glasses. Finally, we analyze the correlation between the atomic mobility and the thermo-mechanical treatments in metallic glasses. On the one hand, the atomic mobility in metallic glasses is reduced by physical aging or crystallization. On the other hand, the atomic mobility in metallic glass is enhanced by deformation (i.e. compression and cold rolling). Importantly, to analyze the atomic mobility in amorphous materials, a physical theory is introduced. This model invokes the concept of quasi-point defects, which correspond to the density fluctuations in the glassy materials.