高熵金属玻璃：近期研究进展

High-Entropy Metallic Glasses: A Review of Recent Research Progress

摘要:

近年来，高熵金属玻璃因其高构型熵，往往呈现出独特的结构特征与性能，包含迟滞扩散效应、结构非均匀性、更高的玻璃形成能力、热稳定性或力学稳定性等，因而受到越来越多的研究关注。尽管与传统金属玻璃一样，高熵金属玻璃原子结构缺乏长程周期性，但是其高熵特性却会引起结构演化的额外复杂性，如导致解耦玻璃转变、潜在的玻璃-玻璃转变以及在再加热过程中的连续多晶型转变的出现。由此，高熵金属玻璃的原子重排和相互作用、化学/拓扑非均匀性具备可调控性，进而使其具有很强的结构与功能应用潜力。尽管已有若干关于高熵金属玻璃的综述报道，鉴于该领域研究的快速推进，本文对高熵金属玻璃合金体系的最新进展做出进一步简要综述与讨论。首先聚焦于新开发高熵金属玻璃的玻璃形成能力；随后，将其不同寻常的结构弛豫、结晶行为及力学性能等与传统金属玻璃相比较；最后，对高熵金属玻璃的原子尺度结构与结构非均匀性特征进行综合评述，并给出总结与展望。

Abstract:

Over the past years, high-entropy metallic glasses (HEMGs) have attracted increasing research interest due to their unique structural characteristics arising from high configurational entropy, as well as distinctive properties such as sluggish diffusion, microstructural heterogeneity, enhanced glass-forming ability (GFA), and improved thermal/mechanical stability. Similar to conventional metallic glasses (MGs), HEMGs lack long-range atomic periodicity; however, the high-entropy effect introduces additional complexity in structural evolution, such as decoupling of the glass transition, potential glass-to-glass transitions, and a continuous polyamorphic transition during reheating. This enables HEMGs with tunable atomic rearrangement, atomic interactions, and chemical/topological heterogeneity, thereby conferring great potential for achieving superior structural and functional properties. Although several review papers have summarized the development of HEMGs, the rapid advancement of this field inspires us to provide a concise overview discussion of the latest research progress in HEMG-forming alloy systems. This review first focused on the GFA of newly developed HEMGs, followed by a comparative analysis of their unusual structural relaxation, crystallization behavior, and mechanical properties relative to conventional MGs. Finally, the unique atomic-scale structure and structural heterogeneity of HEMGs were reviewed, and the review concluded with a summary and outlook.