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

Quench Behaviour of a Metallic Cladding REBCO Coil Containing Copper Strips for Outer Diameter Adjustment

28 Aug 2017, 13:15
1h 45m
Posters Area

Posters Area

Poster Presentation of 1h45m G2 - Quench and Normal-Zone Bahavior Mon-Af-Po1.10

Speaker

Kwangmin Kim (National High Magnetic Field Laboratory)

Description

When a high temperature superconductor (HTS) magnet consisting of a stack of pancake coils is wound, precisely controlling both the outer diameter and number of turns in the coil is difficult, mainly due to manufacturing uncertainty of the HTS tapes. To “arbitrarily” adjust the number of turns in each pancake is often adopted to precisely control the outer diameters, which obviously jeopardizes the ideally designed field homogeneity of the magnet, an important issue particularly for nuclear magnetic resonance or magnetic resonance imaging applications. A common approach is to place intermediate metal strips in-between selected turns of the pancake coils in a way to control both the outer diameter and number of turns to the design values. Yet, if this approach is used for a no-insulation (NI) HTS pancake coil, there is concern whether or not the coil will maintain the self-protecting feature. This paper investigates this issue in experiments in a bath of liquid helium at 4.2 K. An NI pancake coil was wound with metallic cladding REBCO tapes having a 1 – 2 um stainless steel cladding layer. Multiple quench tests were performed with the coil placed in a bore of a 10 T low temperature superconductor background magnet. The post-quench behaviors of the coil were monitored in various operating currents. The tests were repeated as the coil was reconstructed with different configurations such as the number of copper strips, size of strips, and strip locations. The results are expected to provide some insight for the baseline design of our future NI-REBCO NMR or MRI magnets.
ACKNOWLEDGMENTS: This work was supported by the National High Magnetic Field Laboratory (which is supported by the National Science Foundation under NSF/DMR-1157490), the State of Florida, and the KBSI grant (D37611) to S.-G.L.

Submitters Country USA

Primary authors

Kwangmin Kim (National High Magnetic Field Laboratory) Mr Kabindra Bhattarai (Applied Superconductivity Center-NHMFL) Dr Kwanglok Kim (National High Magnetic Field Laboratory) Dr Jang Jae Young (Korea Basic Science Institute) Young Jin Hwang (Korea Basic Science Institute) Mr Sangwon Yoon (SuNAM Co., Ltd.) Mr Thomas Painter (Magnet Science & Technology-NHMFL) Dr SangGap Lee (Korea Basic Science Institute) Seungyong Hahn (Seoul National University / National High Magnetic Field Lab.)

Presentation Materials