Remarkably High Tc and Jc in the (T1,Pb,Bi)(Sr,Ba)2Ca2Cu3O9 System and Its Application in Superconducting Tapes

R. S. Liu；S. F. Wu；D. S. Shy；C. H. Tai；S. F. Hu；D. A. Jefferson

Chinese Journal of Physics

31卷6S期（1993 / 12 / 01）

951 - 959

英文

We have found an efficient and highly reproducible method for the preparation of the homogeneous Tl-1223 powders by the partial substitution of Ba^2+ into the Sr^2+ sites in the (Tl0.6Pb0.2Bi0.2)(Sr2-xBax)Ca2Cu3O9 (Tl-1223) system. A high intrinsic critical current density (Jc) and a high superconducting transition temperature (Tc) were observed in this material. The chemical composition and crystal structure of Tl- 1223 were determined by X-ray diffraction (XRD) and energy dispersive spectrometry (EDS). Superconducting tapes (sheathed in silver) based on the titled system have been fabricated using the powder-in-tube method. Typical critical temperatures (Tc) of around 120 K and transport critical current densities (Jc) of about 1.05 x 10^4 A/cm^2 at 77 K in a zero magnetic field have been routinely obtained on short lengths. (~ 3 cm) of the sintered Tl-1223 tapes after rolling. The Jc at 77 K in a zero magnetic field can be improved to 1.33 x 10^4 A/cm^2 on short lengths of the sintered tapes after rolling and pressing. Moreover, the results on the (Tl,Pb,Bi)(Sr,Ba)2Ca2Cu3O9 long lengths of tapes (~ 12 m), pancake coils and prototype superconducting magnet will also be given.