A new approach to a superconducting joining process for carbon-doped MgB sub(2) conductor

• Published in: Superconductor science & technology 2016-09, Vol.29 (9), p.95001-95007
• Main Authors: Patel, Dipak, Al Hossain, Md Shahriar, Maeda, Minoru, Shahabuddin, Mohammed, Yanmaz, Ekrem, Pradhan, Subrata, Tomsic, Mike, Choi, Seyong, Kim, Jung Ho
• Format: Article
• Language: English
• Subjects: Borides; Carbon; Conductors (devices); Joining; Magnesium compounds; Magnetic resonance imaging; Superconductivity; Wire
• ISSN: 0953-2048; 1361-6668
• DOI: 10.1088/0953-2048/29/9/095001

We report a new approach to a superconducting joining process for unreacted in situ carbon (C)-doped magnesium diboride (MgB sub(2)) wires. To operate a magnetic resonance imaging (MRI) magnet in the persistent mode, the superconducting joints between two conductors are as critical as the other key components. In addition, a stable and reliable joining process enables the superconducting magnet to operate without an external power supply. However, joint results using unreacted in situ C-doped MgB sub(2) wires, which are used for high-field operation, have been limited, and only very poor performance has been obtained. By controlling the pressure inside a joint part, in this study, we successfully obtained current carrying retention in the joint of up to 72% compared to wire without a joint. The closed-circuit resistance of our closed-loop coil was less than 1.8 10 super(-13) Omega at 16.7 plus or minus 4.7 K, as measured by the field-decay measurement method. These results indicate that MgB sub(2) has a promising future in MRI application.