Magnetic Flux Invasion and Field-Capturing in Pulsed-Field Magnetization for Layered MgB2 Bulk Magnets

Tetsuo Oka, A. Takeda, S. Sasaki, J. Ogawa, S. Fukui, T. Sato, J. Scheiter, W. Häßler, J. Katsuki, A. Miura, K. Yokoyama

Research output: Contribution to journalArticle

1 Citation (Scopus)

Abstract

The pulsed-field magnetization experiments have been carried out for the layered MgB2 bulk magnets to clarify the magnetic flux motion during the activation processes. Since MgB2 is characterized as homogeneous, lightweight, and inexpensive HTS material in comparison to RE123 compounds (RE = rare earth), the material may have an advantage of possibly uniform magnetic field generation. The values of applied field Ba which begin to reach the sample center were responsible for the total sample thickness, reflecting the shielding effect to suppress the flux invasion. As well, the estimation on the ratios of trapped field BT over penetration field Bp showed us the reluctant field invasion with increasing sample thickness. The field trapping ratios BT Bp decreased with increasing applied field due to heat generation. In the region over 1.4 T, the drastic flux flow and sudden flux jumps were often observed, which lowered the field-capturing ability. The arriving time which corresponds to the flux increasing speed showed us that the rapid flux invasions which occur in the low-field ranges resulted in the highest field-capturing. This suggests us the possible promotion of field-capturing without significant heat generation.

Original languageEnglish
Article number8255574
JournalIEEE Transactions on Applied Superconductivity
Volume28
Issue number4
DOIs
Publication statusPublished - 2018 Jun 1
Externally publishedYes

Fingerprint

Magnetic flux
Magnets
magnetic flux
Magnetization
magnets
Magnetic fields
Fluxes
magnetization
magnetic fields
heat generation
Heat generation
Rare earth compounds
rare earth compounds
promotion
Shielding
shielding
penetration
Chemical activation
trapping
activation

Keywords

  • Bulk superconductor
  • heat generation
  • magnetic flux
  • magnetization
  • pulsed field

ASJC Scopus subject areas

  • Electronic, Optical and Magnetic Materials
  • Condensed Matter Physics
  • Electrical and Electronic Engineering

Cite this

Magnetic Flux Invasion and Field-Capturing in Pulsed-Field Magnetization for Layered MgB2 Bulk Magnets. / Oka, Tetsuo; Takeda, A.; Sasaki, S.; Ogawa, J.; Fukui, S.; Sato, T.; Scheiter, J.; Häßler, W.; Katsuki, J.; Miura, A.; Yokoyama, K.

In: IEEE Transactions on Applied Superconductivity, Vol. 28, No. 4, 8255574, 01.06.2018.

Research output: Contribution to journalArticle

Oka, T, Takeda, A, Sasaki, S, Ogawa, J, Fukui, S, Sato, T, Scheiter, J, Häßler, W, Katsuki, J, Miura, A & Yokoyama, K 2018, 'Magnetic Flux Invasion and Field-Capturing in Pulsed-Field Magnetization for Layered MgB2 Bulk Magnets', IEEE Transactions on Applied Superconductivity, vol. 28, no. 4, 8255574. https://doi.org/10.1109/TASC.2018.2792530
Oka, Tetsuo ; Takeda, A. ; Sasaki, S. ; Ogawa, J. ; Fukui, S. ; Sato, T. ; Scheiter, J. ; Häßler, W. ; Katsuki, J. ; Miura, A. ; Yokoyama, K. / Magnetic Flux Invasion and Field-Capturing in Pulsed-Field Magnetization for Layered MgB2 Bulk Magnets. In: IEEE Transactions on Applied Superconductivity. 2018 ; Vol. 28, No. 4.
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