Title :
Transport and magnetization critical densities in TlBa/sub 2/Ca/sub 2/Cu/sub 3/O/sub x/ tapes
Author :
Willis, J.O. ; Maley, M.P. ; Kung, P.J. ; Coulter, J.Y. ; Peterson, D.E. ; Wahlbeck, P.G. ; Bingert, J.F. ; Phillips, D.S.
Author_Institution :
Los Alamos Nat. Lab., NM, USA
fDate :
3/1/1993 12:00:00 AM
Abstract :
The powder-in-tube process was used to produce silver-sheathed tapes of TlBa/sub 2/Ca/sub 2/Cu/sub 3/O/sub 8+x/ (Tl-1223). The powder was produced by thalliating a precursor powder mixture to produce the Tl-1223 phase and then heating to drive off excess Tl and reach the Tl-2223 stoichiometry. The tapes were rolled and pressed, each step followed by a 3-h sintering. The 200- mu m-thick tapes show little sign of texturing; however, the critical current shows a small ( approximately 50%) dependence on the direction of the applied magnetic field. Both transport and magnetization measurements indicate relatively strong pinning at high temperatures. The 75 K self-field critical current density is 62 MA/m/sup 2/. Transport measurements reveal the presence of weak links at all temperatures, but with a relatively weak field dependence above approximately=0.1 T.<>
Keywords :
barium compounds; calcium compounds; critical current density (superconductivity); high-temperature superconductors; magnetisation; powder technology; sintering; thallium compounds; TlBa/sub 2/Ca/sub 2/Cu/sub 3/O/sub x/ tapes; high temperature superconductors; magnetization; powder-in-tube process; self-field critical current density; sintering; strong pinning; weak links; Conducting materials; Critical current density; Heating; High temperature superconductors; Magnetic field measurement; Magnetic materials; Magnetization; Powders; Superconducting materials; Superconductivity;
Journal_Title :
Applied Superconductivity, IEEE Transactions on
