Wanghui Li, Professor, Institute of High Performance Computing

Junzhi Cui, Professor

The deformation mechanisms and material strength of CoCrFeMnNi High-Entropy Alloys under shock loading at high strain rates

9:30-10:30 June 27(Thursday), N702

High-entropy alloy (HEA), as a new class of materials, has gained tremendous attention since it was first proposed 20 years ago. The unique characteristics of HEAs lead to excellent mechanical and chemical properties. HEAs are even able to maintain high strength, ductility, and high damage tolerance across a wide temperature range. These advantages make HEAs promising structural materials for aerospace and civil transport, defense, and other engineering applications. Since the dynamic characteristics and the mechanisms of damage and deformation are important in assessing the reliability of structural materials, it is necessary to have an in-depth understanding of their responses to dynamic loading. In this talk, three scientific problems will be discussed: 1) Anisotropy of deformation mechanisms in shocked single-crystal CoCrFeMnNi HEA; 2) Chemical Short-Range Ordering effect on the strength and ductility of CoCrFeMnNi HEA under dynamic loading; 3) Hall-Petch to Inverse Hall-Petch transition of flow stress in nanocrystalline CoCrFeMnNi HEAs subjected to shock loading at high strain rates.

报告人简介：李旺辉，新加坡科技研究局高性能计算研究院研究科学家，于2012获南昌大学土木工程专业学士学位，2018年获华南理工大学固体力学专业博士学位，2017-2018在美国洛斯阿拉莫斯国家实验室博士联合培养，随后入职华南理工大学从事博士后研究，2022年入职新加坡科技研究局高性能计算研究院。长期从事凝聚态物质的冲击压缩和材料动力学的微纳尺度计算模拟和理论分析，聚焦高压高应变率、高温和超低温等极端条件下材料的变形、损伤和破坏行为，以及材料的塑性和相变机制等，力图构建材料微纳结构-材料性能-动加载条件三者的相互关系，为相关先进材料的微纳结构设计和极端条件下的应用提供科学指导。曾主持国家自然科学基金-青年基金项目、中央高校基本科研业务费-面上项目以及横向课题等，曾入选2019年全国博士后创新人才支持计划，广东省力学学会优秀博士论文等，在Acta Materialia, scripta Materialia, International Journal of Plasticity, International Journal of Mechanical Sciences等材料和力学领域的著名期刊发表学术论文30余篇。