TY - JOUR
T1 - Study on Magnetic Flux Dissipation and Field-Trapping Performance of HTS Bulk-Shaped Magnesium Diboride in Pulse-Field Magnetizing Processes
AU - Oka, Tetsuo
AU - Takeda, Akira
AU - Oki, Hayami
AU - Ogawa, Jun
AU - Fukui, Satoshi
AU - Scheiter, Juliana
AU - Häßler, Wolfgang
AU - Yokoyama, Kazuya
AU - Yamanaka, Kengo
AU - Dadiel, Longji
AU - Miryala, Muralidhar
AU - Sakai, Naomichi
AU - Murakami, Masato
AU - Noudem, Jacques
PY - 2019/8
Y1 - 2019/8
N2 - The magnetic flux dissipation from the MgB2 bulk magnets during pulsed field magnetization (PFM) processes has been estimated for the samples fabricated by hot-pressing (HP) and spark plasma sintering (SPS). We defined the parameters as field penetration ratio BP/Ba and the field trapping ratio BT/BP to evaluate the flux motion and performance. The data plots of trapping ratio BT/BP showed us two regions which originate from the fast flux flow and flux jump. The field trapping performance was drastically degraded when the flux jump happened. Flux jump happened at various times after the peak field. A very late flux jump happened at 420 ms which severely degraded the trapped field. This time delay, much larger than the heat propagation time in the MgB2 sample, remains to be explained.
AB - The magnetic flux dissipation from the MgB2 bulk magnets during pulsed field magnetization (PFM) processes has been estimated for the samples fabricated by hot-pressing (HP) and spark plasma sintering (SPS). We defined the parameters as field penetration ratio BP/Ba and the field trapping ratio BT/BP to evaluate the flux motion and performance. The data plots of trapping ratio BT/BP showed us two regions which originate from the fast flux flow and flux jump. The field trapping performance was drastically degraded when the flux jump happened. Flux jump happened at various times after the peak field. A very late flux jump happened at 420 ms which severely degraded the trapped field. This time delay, much larger than the heat propagation time in the MgB2 sample, remains to be explained.
KW - Bulk superconductors
KW - magnesium compounds
KW - magnetic field measurement
KW - magnetization processes
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U2 - 10.1109/TASC.2019.2908752
DO - 10.1109/TASC.2019.2908752
M3 - Article
AN - SCOPUS:85066859512
VL - 29
JO - IEEE Transactions on Applied Superconductivity
JF - IEEE Transactions on Applied Superconductivity
SN - 1051-8223
IS - 5
M1 - 8678817
ER -