Development of Tl-1223 conductors for 77 K HTS applications.

Tl-1223 conductors have been fabricated by the powder-in-tube (PIT) and surface-coated conductor (thick film) techniques. Current densities (J/sub c/) of 20,000 A/cm/sup 2/ and 12,000 A/cm/sup 2/ have been achieved at 77 K in short monofilament tapes and meter-long 37-filament tapes respectively. A large diameter test pancake coil was successfully fabricated with 17 m long PIT tapes. A new process has been developed to achieve grain alignment in PIT Tl-1223. Critical currents of 18 A and a J/sub c/ of 19000 A/cm/sup 2/ has been achieved at 77 K in surface-coated Tl-1223 conductor fabricated by an industrial process. [ABSTRACT FROM PUBLISHER]