时间：2025年7月25日（周五）10:00-12:00

地点：师昌绪楼403室

Atom probe tomography and micromechanics for understanding hydrogen trapping and embrittlement in steels

Eason (Yi-Sheng) Chen

 School of Materials Science and Engineering,Nanyang Technological University,Singapore

Abstract: The presence of hydrogen in metallic materials can cause catastrophicearly fracture that is known as hydrogen embrittlement. Observing the hydrogen and its associated influences in microstructure has been a grand challenge that limits the development of a solution to this problem. To this end, our research group have developed a special tool, cryogenic atom probe tomography (cryo-APT), for hydrogen mapping and applied it in combination with a micromechanical approach to investigate hydrogen embrittlement in steels. Our efforts have led to new insights for deciphering hydrogen trapping and embrittling mechanisms in steels, facilitating the development of the steel microstructure that has a good resistance to hydrogen embrittlement.

Dr. Eason (Yi-Sheng) Chen is a Nanyang Assistant Professor (NAP) and SingaporeNational Research Foundation (NRF) Fellow at the School of Materials Science and Engineering, Nanyang Technological University, Singapore (NTU). His research focuses on materials characterisation, metallurgy, and hydrogen technologies. He specialises in using advanced microscopy techniques such as atom probe tomography (APT) and electron microscopes to develop the structure-property-processing relationship of advanced metallic materials. The insights gained from these endeavours will contribute to a deeper understanding of material behaviour, paving the way for the development of next-generation high-performance materials.

References:

[1] Y.-S. Chen et al."Hydrogen trapping and embrittlement in metals – A review."International Journal of Hydrogen Energy (in print) (2024).  https://www.sciencedirect.com/science/article/pii/S0360319924013326

[2] Y.-S. Chen et al."Observation of hydrogen trapping at dislocations,grain boundaries,and precipitates."Science 367,171-175 (2020).

[3] Y.-S. Chen et al."Direct observation of individual hydrogen atoms at trapping sites in a ferritic steel."Science 355,1196-1199 (2017).

[4] P.-Y. Liu and Y.-S. Chen et al."Engineering metal-carbide hydrogen traps in steels."Nature Communications 15,724 (2024).