Concurrent effects of hydrogen and irradiation defects in alloys

2021 Fiscal Year Final Research Report

• Project/Area Number: 18H01913
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Review Section: Basic Section 31010:Nuclear engineering-related
• Research Institution: The University of Tokyo
• Principal Investigator: ABE Hiroaki 東京大学, 大学院工学系研究科(工学部), 教授 (40343925)
• Co-Investigator(Kenkyū-buntansha): 叶野 翔 東京大学, 大学院工学系研究科(工学部), 特任研究員 (00742199) ; 楊 会龍 東京大学, 大学院工学系研究科(工学部), 特任助教 (10814254) ; 村上 健太 長岡技術科学大学, 工学研究科, 准教授 (50635000)
• Project Period (FY): 2018-04-01 – 2022-03-31
• Keywords: ジルカロイ合金 / 水素化 / 照射損傷 / 重畳効果 / 加速器結合型電子顕微鏡

Outline of Final Research Achievements

Zr alloy is used as a reactor fuel cladding tube and causes deterioration such as corrosion, hydrogen absorption, and irradiation damage under the usage environment. Although each of these has detailed knowledge, their synergistic effect has not been clarified. Therefore, the purpose of this study was to clarify the superimposition effect of the hydrogenation effect and the irradiation effect of the Zr alloy.
Hydrogen was injected into the recrystallized Zry-4, the hydride was observed under a microscope, and changes in the ion-irradiated microstructure were observed in-situ in a transmission electron microscope interfaced with an ion accelerator. It was shown that hydrogen in the solid solution leads to an increase in irradiation defect density, enhancing nucleation. It was also clarified that the capture of hydrogen atoms in defects also enhancing defect growth. Further investigation is ongoing on the simultaneous effects of irradiation and hydrogen.

Free Research Field

原子力材料

Academic Significance and Societal Importance of the Research Achievements

ジルコニウム合金は、その種々の特性から原子炉燃料被覆管用材料として広く使用される。原子炉環境におけるこの材料の劣化挙動には腐食、水素化、照射効果があり、それぞれ多くの知見の蓄積がある。しかしこれらの重畳効果については必ずしも明らかではない。本研究はこの重畳効果（特に水素化と照射）について明らかにしたものである。