Understanding Material Synthesis and Material Degradation at the Atomic Scale: Two Sides of the Same Coin (06/02/23)
Speaker and Affliation:
Dr. Arun Devaraj
Chief Material Scientist-Physical Metallurgy,
Physical and Computational Sciences Directorate,
Pacific Northwest National Laboratory (PNNL), Richland, Washington
Research Faculty – Joint Appointment
George S. Ansell Metallurgical and Materials Engineering Department,
Colorado School of Mines (CSM), Golden, Colorado
When?
06th February, 2023 (Monday), 10:00 AM (India Standard Time)
Venue
KPA Auditorium, Department of Materials Engineering
Abstract
Materials scientists studying processing–microstructure–property relationships dream of knowing how processing influences the exact location of each atom in a material and how that affects its properties. Such detailed understanding of material microstructure can inform novel material processing approaches, including solid-phase deformation processing, to design breakthrough materials with improved properties and performance. This same ideal applies to researchers interested in understanding how atomic locations in materials are modified from the initial state when exposed to extreme environments, such as under corrosive environments or neutron irradiation in nuclear fission and fusion reactors, or at high temperature and stress in internal combustion engines. Understanding atomic-scale mechanisms of material degradation under such extreme conditions enables researchers to design long-lasting, damage-tolerant, and high-performance materials. However, given the multiple length and time scales involved in both material synthesis and degradation phenomenon, often no single characterization method can provide information on materials from the physical component level down to the atomic scale. Therefore, multiple in situ and ex situ materials characterization approaches must be seamlessly integrated with computational simulations and mechanical testing where possible to enable a comprehensive understanding of the relationships between material processing, microstructure, properties, and material degradation under various extreme environments. In Dr. Devaraj’s research team at PNNL, methods spanning electron microscopy, in situ atom probe tomography (APT), in situ synchrotron-based high-energy X-ray diffraction, and neutron diffraction are coupled with relevant predictive computational modeling and simulations to obtain a comprehensive understanding of material synthesis and degradation mechanisms.
About Speaker
Dr. Arun Devaraj is a chief scientist at PNNL and research faculty at CSM. He has discovered principles guiding the mechanisms of non-equilibrium behavior and metastable phase transformations in alloys used for structural and nuclear applications, leading to better understanding of the microstructural control critical to establishing novel processing–microstructure–property relationships. He is recognized for contributions to expanding the application of atom probe tomography (APT) for battery materials, catalysts, and biomaterials. Additionally, he is also recognized for directly correlating APT with transmission electron microscopy and for synchrotron X-ray based material characterization methods and simulations to improve the fidelity of APT results by better understanding the reconstruction artifacts in APT. Dr. Devaraj was awarded a DOE Basic Energy Sciences early career research award in 2020. He is the thrust lead of the PNNL Solid Phase Processing Science Initiative and a principal investigator for the Department of Energy (DOE) Vehicle Technologies Office Powertrain Materials Core Program, the Lightweight Materials Core Program, and National Nuclear Security Administration tritium science programs. Dr. Devaraj has published over 125 peer-reviewed journal articles and was awarded the Ronald L. Brodzinski Early Career Exceptional Achievement Award from PNNL in 2019. Dr. Devaraj is the vice president and a steering committee member of the International Field Emission Society and past leader of an APT focused interest group in the Microscopy Society of America. He is an editor of the PLOS One and editorial board member of npj materials degradation and a guest editor of Microscopy & Microanalysis journal, JOM, and a key reader for Metallurgical Transactions.