Ag-clad Tl0.75Bi0.25Sr1.6Ba0.4Ca 2Cu3Ox tapes were fabricated by a powder-in-tube technique. The starting powders consisted of Bi2Sr2CaCu2Ox plus simple oxides. The tapes were heated in flowing O2 at 835-865°C for 7.5-10 h. Room-temperature pressing at 1.0-1.5 GPa produced tapes with denser, more phase-pure cores, and transport critical current density Jc at 77 K in self-field that was increased by a factor of ≈2. The maximum Jc value of 6 × 103 A/cm2 was obtained with heating at 840-850°C for ≈ 10 h, with three intermediate pressing steps. The cores of the best tapes were still rather porous and contained significant concentrations of nonsuperconducting phases. Published by Elsevier Science Ltd.
All Science Journal Classification (ASJC) codes
- Physics and Astronomy(all)