Dr. Eiichi Wakai (Michigan State University）gave a lecture at NIMS on January 10, 2025 as the ICYS〈354〉& RCSM〈166〉 Special Seminar.
Date and time: January 10th, 2025, 13:30 - 14:30
Venue: Conference room ,5th floor of advanced structural materials research building, NIMS Senge site
Title: Irradiation damage study of materials and the related development for nuclear and accelerator application
Speaker: Dr. Eiichi Wakai (Michigan State University）
Organizer: Dr. Koichi Tsuchiya(Microstructure Analysis Group)
Dr. Eiichi Wakai(front row, 7th from left)
Irradiation damage study of materials and the related development for nuclear and accelerator application
Eiichi Wakai (Michigan State University)
Abstract.
The speaker has been conducting research on material irradiation damage related to fusion reactors, fast reactors, and light water reactor materials, as well as research and development of neutron sources for fusion materials at the Japan Atomic Energy Agency. At the J-PARC Center, where various materials are analyzed, I have also conducted integrity evaluation and improvement of the vessel encasing the mercury target, which has been an issue for powering up the beam at the mercury target type spallation neutron source facility, to withstand high heat loads, etc., and I have also been involved in the I have also cooperated in the evaluation of the durability of titanium alloy equipment used in the neutrino facility. On the other hand, in terms of contributions to the field, the Materials Division of the Atomic Energy Society of Japan completed a roadmap for the field in May 2021. In addition, I am still contributing to the field as one of the editors of the Journal of Nuclear Materials, one of the international journals on nuclear materials. Since June of this year, I have been working at FRIB (Facility for Rare Isotope) at Michigan State University in the U.S., where nuclear physics (top institute in the U.S.) and isotope production (research and application) are conducted, and there are many instruments used in harsh irradiation environments never experienced by mankind before. There are many of them, and we are engaged in material selection, lifetime evaluation of equipment, and research and development of systems (e.g., a wide variety of materials such as Al alloys, Cu alloys, Ti alloys, graphite, Inconel, Lithium, etc. to suit each application and operating environment).
In this talk, I will introduce the basic phenomena and irradiation damage of materials used in environments subjected to high energy particle beams, which I have been involved for research and development of advanced nuclear reactor systems, fusion reactors, and high energy accelerator facilities. Recently, research and development of advanced materials that can be used under more severe irradiation environments has been conducted. In this research, several high entropy alloys (HEA) were fabricated and characterized, and the high temperature strength properties of Ti-based HEA, which were evaluated with the help of NIMS technicians and excellent facility utilization, have proven to have very interesting characteristics. I will also present examples of analysis of irradiation damage in titanium alloys and ultra-hard W-based HEA conducted with the cooperation of NIMS engineers and the use of facilities. In addition, I will also introduce the challenges of collaboration among national laboratories, universities, and industry related to such research and development.
References:
1) E. Wakai, et al., J. Nucl. Mater. 543(2021)152503. 2) E. Wakai, et al., Mater. Characterization, 211(2024)113811. 3) T. Ishida, S. Kano, E. Wakai, et al., J. Alloy and Compounds,995(2024)174701.