[14p-D63-11~21] 11.3 Critical Current, Superconducting Power Applications

▲ [14p-D63-13] Characterization of Current Transport Properties in Multi-filamentary Bi-2223 Tape Based on Magnetic Moment Relaxation Measurement by In-field Magnetic Microscopy

〇Mohan Shyam¹, Hisajima Kohei¹, Higashikawa Kohei¹, Onodera Yuta¹, Suzuki Takumi¹, Inoue Masayoshi¹, Kiss Takanobu¹ (1.Kyushu Univ.)

Keywords:Bi-2223, relaxation

Bi-2223 tapes are used to wind superconducting magnets such as cryocooler cooled high field magnet and MRI magnet. It has been pointed out that a large value of magnetic moment induced in the tape strand causes several issues in the magnet applications. Namely, in-field behavior of such magnetic moment in the tape strand should be relevant as a base of magnet applications. The measurement of magnetic moment relaxation is also important as a method to evaluate critical currents especially at high current region. However, it is not yet clearly understood the influence of coupling between the filaments in multifilamentary Bi-2223 on the magnetization relaxation. Here we investigate whether the Bi-2223 filaments are decoupled at high magnetic fields by performing local magnetization relaxation measurements using scanning Hall probe microscope. We find that remanent field distribution clearly shows coupling of the filaments during relaxation.