报告题目(中文)：金属材料的玻璃形成与晶化

报告题目(英文)：Glass Formation and Crystallization of Metallic Materials

报告内容简介：

The critical cooling rates of metallic materials to avoid crystallization can span over 17 orders of magnitude. The origin of this vast range of glass-forming abilities remains unclear, even with considerable research efforts in the past 60 years. In recent years, we have been focusing on studying the crystallization kinetics and its structural origin in supercooled metallic liquids to understand the physical mechanism of glass formation. By using prototypical metallic systems with distinct glass-forming abilities, we performed large-scale molecular dynamics simulations to monitor the crystallization process. We also utilized enhanced sampling methods to measure the thermodynamics and fine-tune the local orderings. Contrary to common thoughts, we identified the critical role of liquid-crystal interfacial energy in not only crystal nucleation but also in crystal growth. Microscopically, the interfacial energy is determined by the nontrivial coupling between local structural and compositional orderings. The formation of crystal-like pre-orderings effectively wets the nuclei and reduces the topological and chemical gradients at the interface, which decreases the interfacial energy and facilitates crystallization. This finding is further corroborated by an order-killing strategy that can increase the critical cooling rate of a poor glass former by several orders of magnitude. The exceptional importance of competing ordering effects and local chemical orderings unique to metallic glasses is revealed. The findings have been further strengthened from single-component systems simulations and machine learning studies of a large database of binary model alloys. The application of the glass-forming ability new knowledge is explored in assisting the design of high-performance supercooled electrolytes for low temperature secondary batteries.

报告人姓名：胡远超

报告人简介(中文)：松山湖材料实验室研究员，工学博士，博士生导师。于2018年在中国科学院物理研究所和香港城市大学获得博士学位。曾任东京大学JSPS博士后和耶鲁大学助理研究员。主要研究方向为利用分子动力学模拟研究非晶态材料与物理。相关研究工作发表在Nature Physics，Nature Communications，PNAS等国际学术期刊，担任包括Nature，Nature Physics，PRL等知名学术期刊审稿人。

报告人单位(中文)：松山湖材料实验室

报告时间：2024-04-23 13:30

报告地点：材料基因组工程研究院 306

主办单位：上海大学

联系人：王庆