A study on the Stability of Bi-based Superconducting Wires cooled by a Cryocooler

저온냉동기로 냉각된 Bi 계 초전도선재의 안정성 연구

The stability of Bi-based superconducting wires cooled by a cryocooler was studied by considering the temperature dependency of critical current and electrical resistivity. The critical current measured in 23 K was about 7 times higher than that measured in liquid nitrogen of 77 K. The stability behavior of Bi based multifilament wires subjected to a thermal disturbance, which was simulated with a electric heater, was investigated by measuring the variation of voltage drop with time. Current sharing was occurred, and recovery to superconductivity was measured in the wire after removing heater power.