论文信息 - Critical currents in Ag sheathed tapes of the 2223-phase in (Bi,Pb)-Sr-Ca-Cu-O

Critical currents in Ag sheathed tapes of the 2223-phase in (Bi,Pb)-Sr-Ca-Cu-O

The critical current density of Ag-sheathed (Bi,Pb)-Sr-Ca-Cu-O tapes with thicknesses below 0.2 mm exhibiting the 2223 phase has been systematically studied for various compositions and oxygen contents of the surrounding atmosphere. Various sequences of the final thermochemical treatment leading to a textured structure were also examined. Conditions for obtaining a high degree of texturing in Ag-sheathed tapes were found, yielding J/sub c/ values up to 17.500 A/cm/sup 2/ at 77 K, 0 T. A major factor for the improvement of J/sub c/ by the present cold deformation approach was the thickness of the 2223 layer, which should be smaller than 20 mu m. Due to the large number of parameters involved in the optimization of this system and to the complex formation conditions, a substantial further increase of J/sub c/ in the 2223 phase is still expected. This is particularly important in view of the use of 2223 tapes at 4.2 K and at high magnetic fields.

[1] D. Fork,et al. Superconducting Bi-Ca-Sr-Cu-O Fibers Grown by the Laser-Heated Pedestal Growth Method , 1988, Science.

[2] M. Murakami,et al. A New Process with the Promise of High Jc in Oxide Superconductors , 1989 .

[3] E. Suzuki,et al. Evaluation of the Si-SiO2 Interface by the Measurement of the Surface Recombination Velocity S by the Dual-Mercury Probe Method , 1990 .

[4] T. Ishiguro,et al. Advances in Superconductivity II , 1990 .

[5] R. Flükiger,et al. Superconducting and metallurgical properties of bronze processed Nb3Sn wires with Ni and Zn additions and comparison with Ta and Ti additions , 1984 .

[6] T. Kawai,et al. Preparation of the High-Tc Phase of Bi-Sr-Ca-Cu-O Superconductor , 1988 .

[7] Keikichi G. Nakamura,et al. Growth of the 2223 Phase in Leaded Bi-Sr-Ca-Cu Oxide under Reduced Oxygen Partial Pressure , 1989 .

[8] M. Yoshikawa,et al. Single High-Tc Phase Region of the Bi-Pb-Sr-Ca-Cu-O System , 1989 .

[9] M. Kase,et al. Eliminating channeling tail by lower dose preimplantation , 1990 .

[10] Hajime Hitotsuyanagi,et al. Ag-Sheathed Bi-Pb-Sr-Ca-Cu-O Superconducting Wires with High Critical Current Density , 1989 .

[11] Katsuhisa Tanaka,et al. Processing Dependence on Microstructure and Superconducting Properties in the (Bi, Pb)-Sr-Ca-Cu-O System , 1989 .

[12] Y. Matsumoto,et al. Origin of the silver doping effects on superconducting oxide ceramics , 1990 .