TY - JOUR
T1 - Enhancement of Trapped Magnetic Field Using a Large-Size REBCO Bulk in a Desktop Type Superconducting Bulk Magnet
AU - Yokoyama, Kazuya
AU - Katsuki, Atsushi
AU - Miura, Atsuro
AU - Oka, Tetsuo
N1 - Funding Information:
Manuscript received August 25, 2017; accepted December 1, 2017. Date of publication December 12, 2017; date of current version January 23, 2018. This work was supported by JSPS KAKENHI under Grant 15K05951. (Corresponding author: Kazuya Yokoyama.) K. Yokoyama is with the Division of Mechanical and Electrical Engineering, Ashikaga Institute of Technology, Ashikaga 326-8558, Japan (e-mail: k-yokoyama@ ashitech.ac.jp).
Publisher Copyright:
© 2017 IEEE.
PY - 2018/4
Y1 - 2018/4
N2 - We have developed a desktop type superconducting bulk magnet using a Stirling cryocooler with the aim of miniaturizing the magnet system. In our previous study, the lowest achieved temperature of 51.3 K and the maximum trapped field of approximately 2.8 T were achieved by cooling and magnetizing tests using a GdBCO bulk material 45 mm in diameter. For this paper, we remodeled the bulk magnet system in order to attach a large bulk 60 mm in diameter for the purpose of enhancing the total magnetic flux. This was based on the idea that the total magnetic flux was increased if the volume of the bulk was expanded, while we were concerned about the reduction of the trapped field due to the low cooling capacity of the refrigerator and the high ultimate temperature. When cooling and magnetizing tests were carried out using φ60-mm GdBCO bulk, the sample was cooled from room temperature to an ultimate temperature of 55.6 K for approximately 6.5 h, and the total magnetic flux was 2.0 mWb, which was approximately twice that of φ45-mm bulk, indicating that the aim of this study was achieved. The maximum trapped field was 3.0 T, which was the maximum value in pulsed-field magnetization using a large bulk at temperatures beyond 50 K.
AB - We have developed a desktop type superconducting bulk magnet using a Stirling cryocooler with the aim of miniaturizing the magnet system. In our previous study, the lowest achieved temperature of 51.3 K and the maximum trapped field of approximately 2.8 T were achieved by cooling and magnetizing tests using a GdBCO bulk material 45 mm in diameter. For this paper, we remodeled the bulk magnet system in order to attach a large bulk 60 mm in diameter for the purpose of enhancing the total magnetic flux. This was based on the idea that the total magnetic flux was increased if the volume of the bulk was expanded, while we were concerned about the reduction of the trapped field due to the low cooling capacity of the refrigerator and the high ultimate temperature. When cooling and magnetizing tests were carried out using φ60-mm GdBCO bulk, the sample was cooled from room temperature to an ultimate temperature of 55.6 K for approximately 6.5 h, and the total magnetic flux was 2.0 mWb, which was approximately twice that of φ45-mm bulk, indicating that the aim of this study was achieved. The maximum trapped field was 3.0 T, which was the maximum value in pulsed-field magnetization using a large bulk at temperatures beyond 50 K.
KW - REBCO bulk superconductor
KW - Stirling refrigerator
KW - pulsed field magnetization
KW - total magnetic flux
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U2 - 10.1109/TASC.2017.2782680
DO - 10.1109/TASC.2017.2782680
M3 - Article
AN - SCOPUS:85038866552
SN - 1051-8223
VL - 28
JO - IEEE Transactions on Applied Superconductivity
JF - IEEE Transactions on Applied Superconductivity
IS - 3
M1 - 8187669
ER -