Title :
Ag doping effects on the microstructure and properties of unidirectional grown Y-Ba-Cu-O superconductors
Author :
Hirano, N. ; Nagaya, S.
Author_Institution :
Chubu Electric Power Co. Inc., Nagoya, Japan
fDate :
6/1/1995 12:00:00 AM
Abstract :
The Ag doping effects on the unidirectional solidification of YBCO superconductors have been studied. The unidirectional solidification was realized by the zone melting process using an infrared radiation convergence furnace. The continuous crystals were obtained by the process. Ag distributed independently in the intergrain and grain boundary at nearly the same size. Increasing the Ag content, the a-b plane of the 123 superconducting phase aligned to the solidified direction and the (110) textured sample has been obtained by the addition of the 20 wt.%. By the addition of Ag, the I/sub c/ characteristics were improved drastically and the obtained sample (approximately 4 mm in diameter) shows a high critical current value of over 2000 A.<>
Keywords :
barium compounds; critical current density (superconductivity); critical currents; crystal microstructure; directional solidification; grain boundaries; high-temperature superconductors; silver; yttrium compounds; zone melting; 110 textured sample; 123 superconducting phase; 4 mm; Ag doping effects; YBaCuO:Ag; a-b plane; continuous crystals; critical current; critical current density; grain boundary; high temperature superconductors; infrared radiation convergence furnace; intergrain; microstructure; unidirectional grown superconductors; unidirectional solidification; zone melting process; Atmosphere; Convergence; Doping; Furnaces; Grain boundaries; Lamps; Microstructure; Superconductivity; X-ray diffraction; Yttrium barium copper oxide;
Journal_Title :
Applied Superconductivity, IEEE Transactions on