High-Performance Y-based Superconducting Wire and Their Applications

Yttrium(Y)-based superconducting wires are expected to be applied to various superconducting apparatus. They have high current density and show the high performance in liquid nitrogen, which is much cheaper than liquid helium. In 1991, Fujikura succeeded in developing the key original technology to fabricate Y-based superconducting wire, which was called as ion-beam-assisted deposition (IBAD) method. An 816.4 m long wire with end-to-end critical current (Ic) of 572 A/cm, corresponding to the world record Ic x L value of 466,981 Am/cm, was achieved at Fujikura. Today, we have established skills of routinely fabricating 500 m long wires with uniform Ic distribution over 500 A. In this report, we introduce recent improved performance of Y-based superconducting wires and developments of key technologies for their applications.