August 27, 2017 to September 1, 2017
RAI Congress Center, Amsterdam, The Netherlands
Europe/Amsterdam timezone

Design and Implementation of Ferromagnetic Shims for a 3-T 100 mm All-REBCO No-Insulation Magnet

Aug 29, 2017, 1:15 PM
1h 45m
Postera Area

Postera Area

Poster Presentation of 1h45m D1 - Magnets for NMR Tue-Af-Po2.05


Min Cheol Ahn (Kunsan National University)


This paper presents design and implementation of ferromagnetic shims for a conduction-cooled 3-T 100 mm winding diameter no-insulation (NI) all-REBCO magnet. The initial magnetic field profile was measured by an in-house 3-D field mapper with an NMR magnetometer, from which harmonic coefficients up to 3 order are derived. A ferromagnetic shim design code was developed, which includes an optimization process to minimize target harmonic field errors with a given volume of ferromagnetic shims. For experiment, two designed sets of ferromagnetic shim matrices, which consist of 0.025-25 mm thick iron pieces, were attached on two concentric cylindrical tubes of 54 mm and 60 mm in diameter, respectively, and then installed in a 64 mm room temperature bore of the 3 T magnet. Through recursive mapping and shimming steps, the magnet field uniformity was gradually improved from ~500 ppm to ~100 ppm. The results imply the first shimming test of all-REBCO no-insulation magnet, which will be a basis for our upcoming high-resolution all-REBCO NMR magnet currently being developed.
This work was supported by KBSI grant (D37611) to S.-G.L funded by the Korea Basic Science Institute (KBSI).

Submitters Country Korea

Primary authors

Min Cheol Ahn (Kunsan National University) Mr Hongmin Yang (Kunsan National University) Jae young Jang (Korea Basic Science Institute) Young Jin Hwang (Korea Basic Science Institute) Seungyong Hahn (Seoul National University / National High Magnetic Field Lab.) Dr SangGap Lee (Korea Basic Science Institute)

Presentation materials