Enhancement of critical current property on MgB2 supercondcting material by densification and microstrcture control

2019 Fiscal Year Final Research Report

• Project/Area Number: 18K14012
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 26040:Structural materials and functional materials-related
• Research Institution: Tohoku University
• Principal Investigator: Yusuke Shimada 東北大学, 金属材料研究所, 助教 (20756572)
• Project Period (FY): 2018-04-01 – 2020-03-31
• Keywords: 組織制御 / 電子顕微鏡 / 超伝導材料

Outline of Final Research Achievements

Superconductors are expected materials for using as an MRI, a power cable and a high magnetic field magnet because of the remarkable properties. In particular, an MgB2 can be used as polycrystalline materials, and the fabrication process of MgB2 is easier than that of other high temperature superconducting materials. However, the transport current property is insufficient for practical using, which is caused by low volume fraction of sintered MgB2 bulk. In this study, we tried to densify an MgB2 bulk by the introduction of HIP method in a sintering process. Our microstructural observations suggest the influence of HIP method is enhanced by pre-sintering process. On the other hands, we tried to evaluate the progression of densification by three dimensions observation, and we succeeded the imaging pore distribution and digitation of the MgB2 volume fraction.

Free Research Field

材料組織学

Academic Significance and Societal Importance of the Research Achievements

本研究課題は、材料組織学を基にした超伝導材料開発を目的とし、そのなかでも組織制御と組織解析それぞれにおいて熱間等方圧加圧やマクロスケール三次元組織解析といった新規手法を取り入れたものである。その成果として、粉末焼結における熱間等方圧加圧の有用性や注意すべき点を、また電子顕微鏡を用いた三次元組織解析の複雑組織の定量化の可能性を示すことに成功している。さらには、これらの手法は今回注目した多結晶超伝導体の他の材料系においても応用が可能であることを示しており、今後の効率的な材料開発において意義のある成果といえる。