Fabrication of high Tc superconducting tape by solid reaction method

Ag sheathed high Tc superconducting tapes (wires) of YBA2Cu3Oy and Bi1.6Pb0.4Sr2Ca2Cu3Oy were fabricated by the powder-in-tube method. Improvements of the powder core density and the crystal orientation were achieved by the pressing and rolling. The critical current density Jc of 4,140 A./cm2 in Y-systems and of 6,930 A/cm2 in Bi-systems were obtained at 77.3 K in a zero magnetic field. Using these samples, the authors clarify that magnetic dependence of the Jc was largely improved by increasing the Jc at a zero magnetic field. The critical current Jc was uniform within 3% of distribution in a 15 m long wires. A coil made of the rolled wires could generate 64 gauss of the maximum magnetic fields