Investigation of atomic diffusion on magnetic materials

2021 Fiscal Year Final Research Report

• Project/Area Number: 19K15315
• 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: Ibaraki National College of Technology
• Principal Investigator: ONODERA Reisho 茨城工業高等専門学校, 国際創造工学科, 准教授 (80758540)
• Project Period (FY): 2019-04-01 – 2022-03-31
• Keywords: 磁性材料 / 組織制御 / 強磁場効果

Outline of Final Research Achievements

The diffusion coefficient of Fe atoms in Titanium was reduced by 53% by applying a high magnetic field of 19 T. This suppression effect was significantly smaller when a magnetic field of 13 T was applied.
The contribution of magnetic force for atomic diffusion was investigated in magnetic gradients, where the direction of diffusion of Fe atoms into Titanium was parallel and antiparallel to the direction of the magnetic gradient. After heat treatment in a magnetic field, it was found that diffusion was independent of the direction of the magnetic gradient. Therefore, the magnetic field does not suppress atomic diffusion due to a mechanical interaction which has a directional component, but rather contributes as a thermodynamic parameter whose absolute value is the only one to be discussed.

Free Research Field

応用物理

Academic Significance and Societal Importance of the Research Achievements

原子拡散は材料の微細組織形成を支配する要因の一つである．微細組織の特徴によって材料自身の特性が大きく変化するため，微細組織の設計によって，材料特性の制御が容易に行える事になる．本研究の成果は，微細組織を設計するため，パラメーターとして磁場が有用であることを示すことができた．
従来，熱以外での制御が難しい拡散現象を磁場印加によってコントロールできることを示したことで，金属材料の多彩な組織形成を実現し，材料特性向上に大きく資すると期待できる．