Development of a microstructure-thermal history database for accident process estimation to realise early decommissioning of the Fukushima nuclear power plant.

2023 Fiscal Year Final Research Report

• Project/Area Number: 18K04997
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 31010:Nuclear engineering-related
• Research Institution: Hachinohe National College of Technology
• Principal Investigator: Furuya Kazuyuki 八戸工業高等専門学校, その他部局等, 教授 (70354660)
• Project Period (FY): 2018-04-01 – 2024-03-31
• Keywords: 高エントロピー合金 / 耐照射性 / 照射脆化 / 弾き出し損傷 / ナノ硬さ / 低放射化 / 核融合炉 / 小型モジュール炉

Outline of Final Research Achievements

n the next generation of nuclear reactors, higher temperatures will increase energy efficiency, especially in ferrous materials. Under irradiation, ferrous materials with an fcc crystal structure are known to have reduced creep properties and a significantly reduced lifetime. In addition, Co, Ni and other materials are known to have high induced radioactivity. Therefore, a new high-entropy alloy (Fe-20Mn-15Cr-10V-10Al-2.5C) with a bcc crystal structure was produced and characterised for the first time. The present study shows that such an elemental system has previously unknown properties, i.e. hardness exceeding that of pure tungsten and irradiation resistance higher than previously studied fusion reactor materials and various high-entropy alloys.

Free Research Field

鉄鋼材料

Academic Significance and Societal Importance of the Research Achievements

特に高温での高い耐放射線性と耐食性は、基礎科学や応用に供される高エネルギー加速器を用いた施設で扱われる装置にも求められ、さらなる高出力条件が必要とされ、このような高エネルギー負荷に耐える装置や材料が不可欠である。次世代原子力システム（核融合炉、高速炉、新型核分裂炉）、高エネルギー加速器ターゲットシステム、航空機や自動車の磁気モーターなど、より高性能（強度、耐熱性など）で低放射化特性を持つ革新的な材料やデバイスが求められている中で、本研究は、優れた高温強度や耐食性を有するだけで無く、放射化し難く、照射損傷にも強い新しい合金の創製を目指しており、本合金がもたらす革新的な波及効果は計り知れない。