Formation and Recovery Behavior of Hetero-Nanostructured Metals Processed by High-Pressure Torsion (22/08/24)
Speaker and Affliation:
Professor Megumi Kawasaki
School of Mechanical, Industrial and Manufacturing Engineering, Oregon State University, Corvallis, OR 97330 U.S.A.
When?
22nd August, 2024 (Thursday), 3.00 PM (India Standard Time)
Where
KPA Auditorium, Dept. of Materials Engineering, IISc, Bangalore
Abstract
This presentation provides an overview of the significance of novel and innovative microstructural and microscopic characterization techniques in identifying the formation and recovery behaviors of hetero-nanostructured metals processed through severe plastic deformation, with a focus on high-pressure torsion (HPT). Specifically, the microstructural relaxation behavior upon heating of nanostructured 316L stainless steel and CoCrFeNi high-entropy alloy was characterized by in-situ heating neutron diffraction measurements; the heterogeneous phase distribution of an HPT-bonded hetero-nanostructured Al-Mg alloy was examined using synchrotron high-energy X-ray diffraction; and the microstructural evolution upon heating of a nanostructured CoCrFeNiMn high-entropy alloy was examined by laser-scanning confocal microscopy. These advanced techniques complement each other and other in-situ or ex-situ testing methods, particularly when nanocrystalline metals undergo microstructural and compositional transformations with temperature and time in a hierarchical manner. The outcomes of the studies emphasize the importance of the methodologies and the development of characterization techniques for further in-depth exploration in the research field of severe plastic deformation.
Speaker Bio:
Megumi Kawasaki is a Jack R. Meredith Faculty Scholar and an Associate Professor in the School of Mechanical, Industrial, and Manufacturing Engineering at Oregon State University. She previously served as an Associate Professor at Hanyang University in Seoul, South Korea, from 2012 to 2017. Additionally, she currently holds a Visiting Research Associate Professor position in Materials Science at Osaka Metropolitan University, Japan, since 2013.
Dr. Kawasaki earned her Bachelor of Engineering (B.Eng.) degree in Metallurgy and Materials Science from Osaka Prefecture University, Japan, in 2002. She then received an M.S. degree in 2004 and a Ph.D. degree in 2007 in Materials Science at the University of Southern California.
Dr. Kawasaki’s research expertise lies in the processing of bulk nanostructured metals and materials using severe plastic deformation techniques, as well as characterizing the microstructural evolution of nanostructured materials under extreme conditions such as stress and heat using X-ray and neutron diffraction, as well as synchrotron high-energy X-rays. She has collaborated actively with many researchers around the world and has published over 250 papers in peer-reviewed journals in the last fifteen years. She is currently listed on the Web of Science with an h-index of 50. She is a member of the International NanoSPD Steering Committee and serves as the Chairperson for the international conference on superplasticity in Advanced Materials (ICSAM).