초전도 전류리드의 제작에 관한 연구

A Study on the Manufacture of Current Leads Superconductors

An electric current is supplied to superconducting devices by means of current carrying leads between the power source and the superconducting device. Superconducting current lead is one of the most promising applications of the superconductors, because it has an advantage of decreasing heat conduction to region comparing with a conventional metal lead. With the view of applying to superconducting current leads for superconducting magnet systems and for other cryogenic power handling systems, Bi-2223, Ag tube superconducting tapes were fabricated and their thermal conductivities were calculated from 4 K to 77 K. Bi-2223, Ag mono-filament wires of critical current(Ic) 12A at 77 K under the self-field condition were fabricated using a Powder-In-Tube method. In a way, the problem of optimizing current leads by varying their cross-section and along the length was investigated both numerically and experimentally. To improve the performance of current leads, variable cross-sectional area is studied. Variable cross-sectional area current lead has lower heat leak into cryostat and less material cost than constant cross-sectional area leads.