Review of core technologies for development of 2G HTS NMR/MRI magnet: A status report of progress in Korea University

Song, Jung-Bin; Choi, Yoon Hyuck; Yang, D. G.; Kim, Y.G.; Kim, K.L.; Lee, H.G.

doi:10.1016/j.rinp.2017.08.046

Cited by 12 publications

(7 citation statements)

References 71 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The latter can be operated with multiple resistive soldered joints between superconductor sections [58], while PCM requires superconducting joints between all series-connected conductors as discussed by Parizh et al [20]. Several methods have been developed in order to demonstrate practical fabrication of REBCO-REBCO superconducting joints [15,56,59,60]. Some of the technologies have also been tested for implementation in e.g.…”

Section: Ultra-high-field Magnetic Systems and Coated Conductorsmentioning

confidence: 99%

Topical Review: Multifilamentary coated conductors for ultra-high magnetic field applications

Wulff

Abrahamsen

Insinga

2021

Supercond. Sci. Technol.

View full text Add to dashboard Cite

High-temperature superconducting coated conductors (CCs) are considered an enabling ultra-high field (UHF) tape-conductor technology due to their extremely high engineering current densities at very high magnetic fields and low temperatures, and high mechanical strength. A major challenge is however related to induction of problematically large superconducting screening currents (as an effect of the large width-to-thickness ratio) when the wide tape conductors are exposed to strong transverse magnetic fields above 20 T, which is the case in many UHF magnet systems. Subdividing the superconducting layer into narrow parallel decoupled filaments has been shown to effectively reduce superconducting screening currents by a factor comparable to the number of filaments. The filamentization is however not effective until the induced coupling currents flowing across the filaments have decayed. The effectiveness of the multifilamentary structure in suppressing coupling currents and reducing the decay time constants is directly linked to potential current paths between filaments. Very recent experimental and numerical studies have examined both the challenge of magnet precision, caused by screening-current-induced fields, and the fatal consequences of local uneven tape stresses exceeding the irreversible limits for commercial CCs. These studies have conclusively revealed that screening currents must not be ignored in the mechanical design and other studies have introduced multifilamentary CCs as a viable solution. This paper aims to review the efforts made in developing and investigating multifilamentary CCs for ultra-high field applications focusing on the screening-current-related mechanisms, critical system-level effects, effectiveness of filamentization in UHFs, fabrication and large-scale analysis of multifilamentary CCs, in addition to providing cost estimates of previously studied filamentized CC fabrication techniques.

show abstract

Section: Ultra-high-field Magnetic Systems and Coated Conductorsmentioning

confidence: 99%

Topical Review: Multifilamentary coated conductors for ultra-high magnetic field applications

Wulff

Abrahamsen

Insinga

2021

Supercond. Sci. Technol.

View full text Add to dashboard Cite

show abstract

“…Thus, present HTS applications rely on soldering [6] to join the HTS tapes. The contact resistance however limits the number of allowable joints for persistent mode operation [7,8]. • Layer winding (LW), where the whole coil is wound continuously in layers.…”

Section: State-of-the-art Of All-superconducting High Field Magnetsmentioning

confidence: 99%

Generation of 25 T with an all-superconducting magnet system: field profile and field quality measurements of a layer-wound 4 T REBCO insert coil for a 21 T LTS magnet

Barth

Komorowski

Vonlanthen

et al. 2019

Supercond. Sci. Technol.

View full text Add to dashboard Cite

High temperature superconductors, especially rare-earth barium copper oxide (REBa2Cu3O7−x or REBCO) tapes are an enabling technology for magnetic fields beyond 23.5 T, the limit of the existing technology based on the low temperature superconductors (LTS) niobium–titanium (NbTi) and niobium–tin (Nb3Sn). Due to their higher prices, REBCO tapes are in general only employed as insert coils in an LTS outsert. Due to the tape geometry, the effect of the screening currents is high in REBCO insert coils. The resulting screening current-induced field (SCIF) can distort the shape and magnitude as well as affect the temporal stability of the field after charging. Their influence has to be well understood and it can be a limiting factor in field quality critical applications such as nuclear magnetic resonance magnets. In this work, we present the test results of a layer-wound 4 T REBCO insert coil operated in the background of a 21 T LTS outsert reaching a combined field of 25 T. Using an array of 13 calibrated Hall sensors, we investigate the spatial and temporal effects of the SCIFs at different background fields. Series expansion is employed to separate the contributions of the insert and of the outsert. We present in this work the characterization of the effect of the SCIF on the shape of the field and on its temporal stability in background fields from 0 T up to 19 T. We compare the experimental results with existing simulation models for the validation of the model at high magnetic fields, which had never been done for layer-wound REBCO coils. Based on the experimental data, we demonstrate the necessity of SCIF-aware simulations for REBCO insert coils, regardless of the insert’s relative operating current. Before summarizing and concluding the work, we give a short overview of proposed methods for SCIF reduction in REBCO coils from the literature.

show abstract

“…However, they do provide the highest irreversibility line H irr (see gure S1 in the supplementary information for YBCO). Therefore, besides being suitable for power cables and fault current limiters at low magnetic elds and high temperatures 7 , REBCO CCs have been included in the design and fabrication of new coil architectures for high magnetic eld applications such as research magnets [8][9][10][11][12] , NMR/MRI magnets 13 , magnets for fusion energy [14][15][16] , and high energy physics accelerator magnets 17 . They are excellent candidates not only for superconducting large currents in high eld magnets at very low temperatures, but also in the intermediate magnetic elds generated in rotating machines 18 or superconducting magnetic energy storage systems 19,20 at temperatures in the range of 20-50 K, which can be effectively driven by cryocoolers 21 .…”

Section: Introductionmentioning

confidence: 99%

Optimal Vortex Pinning in YBa2Cu3O7-x Superconducting Films Up to Very High Magnetic Fields

Vallès

Palau

Abraimov

et al. 2022

Preprint

View full text Add to dashboard Cite

The magnetic flux pinning capabilities of YBa2Cu3O7−x (YBCO) coated conductors (CCs) vary strongly between different regions of the magnetic field-temperature (H-T) diagram and with the orientation of the magnetic field (θ). Here, we determine the optimal pinning landscape for a given H-T region by investigating the critical current density Jc(H,θ,T) in the 5-77 K temperature range, from self-field to very high magnetic fields (35 T). Our systematic analysis reveals the best directions to target to artificially engineer CCs in any region of interest. In solution-derived nanocomposites, we identify the relevance of coexisting high amounts of short stacking faults, Cu-O vacancy clusters and segmentation of twin boundaries, in combination with nanoparticles, for enhanced pinning performance at very high magnetic fields and low temperatures. Moreover, we demonstrate that twin boundaries preserve a high pinning energy in thick YBCO films, which is beneficial for the pinning performance at high magnetic fields and high temperatures.

show abstract

Review of core technologies for development of 2G HTS NMR/MRI magnet: A status report of progress in Korea University

Cited by 12 publications

References 71 publications

Topical Review: Multifilamentary coated conductors for ultra-high magnetic field applications

Topical Review: Multifilamentary coated conductors for ultra-high magnetic field applications

Generation of 25 T with an all-superconducting magnet system: field profile and field quality measurements of a layer-wound 4 T REBCO insert coil for a 21 T LTS magnet

Optimal Vortex Pinning in YBa2Cu3O7-x Superconducting Films Up to Very High Magnetic Fields

Contact Info

Product

Resources

About