报告人：Gang Ji，National Centre for Scientific Research (CNRS), Lille France
报告时间：7月25号下午3点
报告地点：机械楼A311
报告摘要:
Aluminium matrix composites (AMCs) for structural applications usually integrate ceramic reinforcement (nano-)particles into an aluminium matrix, leading to improved mechanical performance, particularly in the case that high strength and Young’s modulus are necessary. Nature of the interface between the reinforcement particles and aluminium matrix defines how such ceramic particles can be used to achieve favourable mechanical properties in AMCs. However, strength-ductility trade-off is usually an inevitable scenario in most AMCs where introduction of reinforcement particles significantly degrades ductility. To address this challenge, we proposed a new precipitation-assisted interface tailoring (PAIT) mechanism to improve the coherency of interface between reinforcement particles and matrix by introducing a three-dimensional (3D) interphase (IP). Using an AlZnMgCu matrix composite reinforced with nano-TiB2 particles as the model material, the 3D IP was properly introduced by conventional manufacturing to improve the coherency and strength of the TiB2/Al interface with the aim of transforming the high mismatch TiB2/Al interface into the low mismatch TiB2/3D IP/Al multi-interfaces. This effectively promotes dislocation multiplication and subsequent dislocation annihilation to increase the work hardening rate by restricting the dislocation pile-ups surrounding the interface, thus leading to a higher ductility. More recently, we found the above-mentioned beneficial TiB2/3D IP/Al multi-interfaces can be delicately tailored not only by conventional processing, such as heat treatment, but also by rapid solidification techniques, such as laser direct energy deposition (L-DED). This talk will mainly address the critical interface aspects of AMCs like interface characterization and engineering.
个人简介:
Dr. G. JI obtained his Bachelor and Master degrees at Shanghai University in China and his Ph.D. degree at Université de technologie de Belfort Montbéliard (UTBM) in France. He joined CNRS as a permanent researcher in 2008. His current research interests include (1) design and engineering of interfaces of advanced metal matrix (nano-) composites for improved mechanical and thermal properties; (2) characterization and understanding of the metastable and anisotropic microstructure and defects in alloys and composites developed by additive manufacturing and (3) atomic-scale characterization for the local transformation of structure, chemistry and properties in complex multiphase materials. In his career to-date, Dr. JI has published around 150 peer-reviewed journal papers including Acta Mater., Angewandte Chimie, Nature Mater., (h-index: 41 from Google Scholar) and has around 100 contributions in international conferences. He is a member of editorial boards of journals “Nano Materials Science” and “Metals”. He was rewarded a 2016 Gledden Fellowship by University of Western Australia in Australia, 2023 IAAM scientist medal and is a guest Professor of the State Key Laboratory of Metal Matrix Composites at Shanghai Jiao Tong University in China.
