DEVELOPMENT OF SILVER-SHEATHED BISMUTH SUPERCONDUCTING WIRES AND THEIR APPLICATION (INVITED)

The development results for silver-sheathed bismuth (2223 phase) superconducting wires in the past two years have suggested that three different fields of application will be feasible in the very near future. The first field is large current conductor application in liquid nitrogen operation. The second is magnet application (relatively low magnetic field below 1 Tesla, such as for semiconductor crystal pulling and magnetic separation) in liquid nitrogen operation. The third is super-high field application above 20 Tesla in liquid helium operation. In this paper, we will describe the state of the art of high-T(c) superconducting wires using a combination of bismuth high-T(c) phase and powder-in-tube technique. Maximum J(c) at 77.3 K reached to 53 700 A/cm2 in a zero magnetic field, 42 300 A/cm2 at 0.1 Tesla and 12 000 A/cm2 at 1 Tesla. Prototypes, such as a 1000 A carrying conductor at 77.3 K, a 1000 Gauss coil at 77.3 K and a super-high field coil at 4.2 K were made and tested successfully.