Effects of Melting Diffusion and Annealing in Oxygen on Superconducting Characteristics of GdBCO Coated Conductors: Preliminary Results

119

Persistent current joints are crucial components of superconducting magnets—enabling the production of the high and ultra-stable magnetic fields required, for instance, for magnetic resonance measurements. At this critical juncture when persistent mode magnets containing commercial high temperature superconductors may soon become a reality, it is of value to take stock and evaluate current challenges faced in the field of jointing. This paper provides a review of progress made to date on the production and characterization of joints between the five major technological superconductors—NbTi, Nb3Sn, MgB2, BiSCCO and REBCO, including the materials that are used to make these joints.

Section: Joints Between Rebco Superconductorsmentioning

confidence: 92%

“…In a series of publications [9,71,74,86] Park et al have documented the successful development of a joint between GdBCO CCs that addresses all of the above problems. In their process, the GdBCO is first exposed for jointing by dissolving the Ag with a KI + I based etchant.…”

Section: Joints Between Rebco Superconductorsmentioning

confidence: 99%

Persistent current joints between technological superconductors

Brittles

Mousavi

Grovenor

et al. 2015

119

“…The ceramic nature of CCs and their extreme sensitivity to oxygen and high temperatures preclude typical metallurgical jointing approaches, proven successful with LTS. To date, a technique developed recently by Y J Park et al [102] gives encouraging results. This approach consists in sintering two counter-facing ceramic layers in vacuum (>800 °C) and restoring the optimal oxygen content by a special heat-treatment performed at a lower temperature.…”

Section: Coil Insulationmentioning

confidence: 99%

Progresses and challenges in the development of high-field solenoidal magnets based on RE123 coated conductors

Senatore

Alessandrini

Lucarelli

et al. 2014

248

136

Recent progresses in the second generation REBa 2 Cu 3 O 7 − x (RE123) coated conductor (CC) have paved a way for the development of superconducting solenoids capable of generating fields well above 23.5 T, i.e. the limit of NbTi−Nb 3 Sn-based magnets. However, the RE123 magnet still poses several fundamental and engineering challenges. In this work we review the state-ofthe-art of conductor and magnet technologies. The goal is to illustrate a close synergetic relationship between evolution of high-field magnets and advancement in superconductor technology. The paper is organized in three parts: (1) the basics of RE123 CC fabrication technique, including latest developments to improve conductor performance and production throughput; (2) critical issues and innovative design concepts for the RE123-based magnet; and (3) an overview of noteworthy ongoing magnet projects.

“…In 2013, Lee et al [25] and Park et al [26][27][28] reported a superconducting joint between REBCO conductors, which had a significant impact on the magnet technology research and materials science. While the magnet technology researchers expected to develop the persistent-mode magnets, the materials scientists expected to create an improved HTS superconducting joint methodology.…”

Section: Overview Of the Superconducting Joint Technology For Hts Con...mentioning

confidence: 99%

“…In 2013, Lee et al [25] and Park et al [26][27][28] overcame these shortcomings by introducing a superconducting joint between the REBCO conductors using a direct-type joining method. However, this method exhibited insufficient robustness against mechanical stress.…”

Section: Introductionmentioning

confidence: 99%

Review of the temporal stability of the magnetic field for ultra-high field superconducting magnets with a particular focus on superconducting joints between HTS conductors

Takeda¹,

Maeda²,

Ohki³

et al. 2022

Superconducting magnets used in applications such as magnetic resonance imaging (MRI) and nuclear magnetic resonance (NMR) require significant temporal magnetic field stability, which can be achieved when the MRI and NMR magnets are operated in the persistent current mode (persistent-mode) using superconducting joints. However, the ultra-high field MRI and NMR magnets are sometimes operated in the driven mode. Herein, we present an analysis of the temporal magnetic field drift and fluctuations observed for MRI and NMR magnets operating in the driven mode and an exploration of effective methods for stabilizing the temporal magnetic field fluctuations. In the last decade, substantial improvements have been achieved in superconducting joints between high-temperature superconductors (HTS). These superconducting joints enable the development of persistent-mode ultra-high field magnets using HTS coils. Therefore, we herein review the superconducting joint technology for HTS conductors and describe the results of the persistent-mode operation achieved by a medium-field NMR magnet using an HTS coil. Particularly, the cutting-edge progress achieved concerning HTS superconducting joints, including joining methods, superconducting properties, and future prospects, is highlighted along with the issues that need to be addressed.