MSE Special Seminar: Advanced TEM/STEM Characterization of Interfacial Dynamics...
Tuesday, March 24, 2020
via Zoom only
Speaker: Yang Yang, Postdoc Fellow at NCEM, Lawrence Berkeley National Lab
Title: Advanced Electron Microscopy Characterization of Interfacial Dynamics under Extreme Environments
The degradation of materials under extreme environments, such as corrosion, radiation damage, mechanical deformation and high temperatures, has significant social and economic impacts. Degradation not only limits the lifetime and robustness of portable devices, bridges buildings, etc., but it also compromises the safety of nuclear energy. A mechanistic understanding of how materials fail is key to the development of more damage-resistant materials. However, research in this direction has been hindered by several difficulties, i.e., degradation processes are highly dynamic and usually occur at interfaces that are difficult to probe.
In this talk, Dr. Yang will discuss how advanced electron microscopy techniques – such as in-situ transmission electron microscopy (in-situ TEM), environmental TEM (E-TEM), three-dimensional (3D) electron tomography, and four-dimensional scanning transmission electron microscopy (4D-STEM) – open new avenues to overcoming these challenges. First, he will show why aluminum has a superior oxidation-resistance in dry air by comparing the stress corrosion cracking (SCC) process in aluminum to that of zirconium. Afterwards, he will present the study of molten salt corrosion, typical of next generation nuclear reactors. Finally, he will discuss how in-situ TEM techniques could be used to elucidate the improved radiation damage tolerance in novel nanostructured materials.
Dr. Yang Yang is currently a postdoc at National Center for Electron Microscopy (NCEM) in Lawrence Berkeley National Laboratory. He received a PhD degree from the Department of Nuclear Science and Engineering at MIT. During his PhD study, he has visited the Center for Functional Nanomaterials (CFN) at Brookhaven National Laboratory for more than two years to conduct in-situ environmental transmission electron microscopy studies. His research interests include advanced electron microscopy characterization of materials degradation under extreme environments, as well as developing advanced computation tools for understanding interfacial dynamics during ion radiation in solids. He is one of the main developers of IM3D, a full-3D Monte Carlo (MC) simulation tool for ion radiation in matter.