Project/Area Number |
10650312
|
Research Category |
Grant-in-Aid for Scientific Research (C)
|
Allocation Type | Single-year Grants |
Section | 一般 |
Research Field |
Electronic materials/Electric materials
|
Research Institution | Nagasaki University |
Principal Investigator |
FUKUNAGA Hirotoshi Nagasaki Univ., Fac. of Engng., Professor, 工学部, 教授 (10136533)
|
Co-Investigator(Kenkyū-buntansha) |
NAKANO Masaki Nagasaki Univ., Fac. of Engng., Research Associate, 工学部, 助手 (20274623)
KANAI Yasuhisa Nagasaki Univ., Fac. of Engng., Lecturer, 工学部, 講師 (00264200)
|
Project Period (FY) |
1998 – 1999
|
Project Status |
Completed (Fiscal Year 1999)
|
Budget Amount *help |
¥2,600,000 (Direct Cost: ¥2,600,000)
Fiscal Year 1999: ¥900,000 (Direct Cost: ¥900,000)
Fiscal Year 1998: ¥1,700,000 (Direct Cost: ¥1,700,000)
|
Keywords | low permeability / magnetic loss / amorphous / crystallization / domain wall / pinning site / magnetization rotation / dc-biased field |
Research Abstract |
An excessive annealing of amorphous Fe-Cu-Nb-Si-B ribbons precipitated FeィイD22ィエD2B fine crystallites in the nanostructured Fe-Cu-Nb-Si-B mother phases. The precipitated crystallites played the role of pining sites of domain walls, and reduced the permeability of the ribbons down to approximately 300 without a significant increase in magnetic loss. The magnetic loss of the developed ribbons is comparable with that of Mn-Zn ferrite and an amorphous cut core with air-gaps, and the saturation magnetization of the ribbons is approximately three times as high as that of ferrite. In addition, the permeability of the ribbons can be adjusted to a desired value after preparation of a core. Further investigation on magnetic properties under a dc-biased field, however, revealed that the magnetic loss of the prepared ribbons increases significantly under a dc-biased field, and that the magnetization rotation mode is preferred for reducing magnetic loss under a dc-biased field. Thus, nanostructured Fe-Cu-Nb-Si-B ribbons in which the magnetization changes by its rotation were also developed by using the creep-induced anisotropy, and a gap-less magnetic core with low loss and low permeability was prepared from the prepared ribbon. Actually, the magnetic loss of the prepared core did not increase even under a dc-bias field. The saturation magnetization of the prepared core is approximately three times as high as that of ferrite, and the constancy of its permeability under a dc-bias field is superior than that of a ferrite core. In addition, the magnetic loss of the core is 2/3 of that of a ferrite core (100kHz, 0.1T, under a dc-bias field). Therefore, the developed core is considered to be applied to electronic devices.
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