Development of Highly Toughened Tungsten Laminated Composites with Plant Accident Tolerance and Challenge to Room Temperature Ductility

2022 Fiscal Year Final Research Report

• Project/Area Number: 18H01196
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Review Section: Basic Section 14020:Nuclear fusion-related
• Research Institution: Tohoku University
• Principal Investigator: Nogami Shuhei 東北大学, 工学研究科, 准教授 (00431528)
• Co-Investigator(Kenkyū-buntansha): 能登 裕之 核融合科学研究所, ヘリカル研究部, 助教 (50733739)
• Project Period (FY): 2018-04-01 – 2023-03-31
• Keywords: タングステン / 複合材料 / 延性 / 耐酸化性 / 再結晶

Outline of Final Research Achievements

Oxidation-resistant grain refined W-alloy laminates, that combines the advantages of grain refined W-alloy and W-foil laminate, and furthermore, adds oxidation resistance through the addition of Cr, were developed. Although the developed grain refined W alloy showed oxidation resistance, it was found that the ductility could not be adjusted due to the high hardness caused by the addition of Cr. Therefore, it was determined that it would be difficult to achieve the research initial goal with the addition of Cr. On the other hand, the prospect of property improvement was obtained by reducing Cr and adjusting manufacturing conditions, and it also became clear that ductile W laminate could be realized using a material with high hardness and low ductility as a base material, so further research was conducted to determine the possibility of achieving the initial goal.

Free Research Field

核融合炉材料

Academic Significance and Societal Importance of the Research Achievements

従来のW系材料の開発では、機械特性や耐酸化性など個別の課題を解決した材料は開発されていたものの、実機適用まで見据えた全ての課題を同時に解決しうる材料は少なかった。本研究は、W系材料の課題である室温以上における脆性と、再結晶による機械特性劣化を同時に克服し、さらに高温機器の事故時において不可欠な耐酸化性を備えた材料を開発する点が特徴であり、W系材料を適用した高温機器の構造健全性の改善が期待される。この開発知見は、W系材料のみならず、多くの高融点脆性金属材料に水平展開可能となり得る点も指摘するべきであり、核融合炉のみならず様々な機器の構造健全性の改善に資することが期待される。