Development of twisted high‐temperature superconductor composite conductors

Multifilamentary high‐temperature superconductor (HTS) composite conductors have been developed for alternating current (ac) applications. A twisted HTS conductor containing the Bi‐2223 phase fabricated using a modified powder‐in‐tube technique is reported. Transport critical current densities of 13 800 and 10 900 A/cm 2 (77 K, self‐field, 1 μV/cm) have been achieved for twisted tape and wire conductors with twist pitches of 3.7 and 3.6 mm, respectively. These conductors are strongly linked and are thus suitable for use in ac applications.