Micro-Mechanical Behavior of Ultrafine-Grained Materials (23/08/24)
Speaker and Affliation:
Professor Megumi Kawasaki
School of Mechanical, Industrial and Manufacturing Engineering, Oregon State University, Corvallis, OR 97330 U.S.A.
When?
23rd August, 2024 (Thursday), 3.00 PM (India Standard Time)
Where
KPA Auditorium, Dept. of Materials Engineering, IISc, Bangalore
Abstract
Bulk ultrafine-grained (UFG) materials typically exhibit superior mechanical and physical properties. The micro-mechanical deformation behavior of these materials can be closely observed using the nanoindentation technique, especially following significant microstructural changes induced by high-pressure torsion (HPT) processing. This presentation highlights the evolution of small-scale mechanical responses, as examined through nanoindentation, across various UFG materials including a ZK60 magnesium alloy, TiAl intermetallic compound, and an equiatomic CoCrFeNiMn high-entropy alloy. A recent work on nanoindentation coupled with TEM analysis demonstrated the microstructural basis of the extended radiation tolerance by both dislocation suppression and reduced softening in the nanostructured high-entropy alloy after heavy-ion irradiation at 500 ◦C. The work presented will give special emphasis on identifying the stress-strain relationship within the limited volume of UFG materials by utilizing different indentation tip geometries, and on understanding the evolution of micro-mechanical behavior in these materials by estimating strain rate sensitivity.
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).