Wonhee Cho and Cho Hyun Lee, master's students in Prof. Jae-Bok Seol's research team (Artificial Intelligence Analysis and Defense and Aerospace Materials Laboratory) at the Department of New Materials Engineering, were recently selected as the best oral presentation at the Korean Society of Welding and Joining for their paper “Hydrogen Localization Analysis in Steel”. In addition, Cho Hyun Lee was awarded the Best Paper Award (Jung In Sang Award) at the Korean Society of Heat Treatment Engineering's Autumn Conference.

Wonhee Cho and Cho Hyun Lee participated in an international cooperation project with Sydney University in Australia from 2022 to study and conduct experiments to analyze hydrogen in steel. As a result of their joint research with the University of Sydney, they discovered for the first time in Korea that hydrogen is distributed in the grain boundaries and dislocations of steel through the latest analytical techniques.   

In addition, Chohyun Lee presented a paper titled 'Understanding the tensile deformation behavior of STS316L undergoing phase transformation at ultra-low temperature 4.2K' at the conference, and identified the correlation between the increase in ductility using twin boundaries at ultra-low temperature 4.2K.

In this study, the transformation mechanism from austenite to α'-martensite at ultra-low temperature of 4.2K was identified, and wavefront analysis at 298K, 77K, and 4.2K was performed to identify the cause of increased ductility and serration due to micro-dimple formation.

The results of this study are expected to contribute to the development of steel materials used in the hydrogen economy as well as minimizing carbon emissions to reduce greenhouse gas emissions.