Development of Nb3Sn superconducting wires for high field magnets at Kobe Steel and JASTEC

Abstract Research and development activities and some recent results related to Nb 3 Sn superconducting wires in Kobe Steel, Ltd. (KSL) and Japan Superconductor Technology Inc. (JASTEC) are introduced. First, an outline of the activities is described briefly from a historical point of view. Following that, improvements in the characteristics (i.e., critical current density ( J c ), n -value and mechanical properties) of bronze-processed Nb 3 Sn wires are reviewed. Finally, the status of development for the Ta–Sn powder-in-tube (TS-PIT) process is briefly discussed.