Title :
Development of a melt processing route for the fabrication of Tl-1223 coils
Author :
Moore, J.C. ; Hyland, D. ; Fox, S. ; Naylor, M.J. ; Wivell, S. ; Grovenor, C.R.M.
Author_Institution :
Dept. of Mater., Oxford Univ., UK
fDate :
6/1/1997 12:00:00 AM
Abstract :
Tl-1223 tapes with engineering critical current densities, (E-J/sub c/) values of 2500 Acm/sup -2/ can be routinely fabricated but the magnetic field properties are poor due to weak link effects. We have developed a partial melt processing route which results in increased grain growth with greater potential for achieving grain alignment. We have investigated the effect of Tl-1223 phase composition on the melt process and found that Bi substitutions lead to an increased grain size in tapes made using unreacted powder but a decrease in grain growth in tapes made with reacted powder.
Keywords :
barium compounds; bismuth compounds; calcium compounds; critical current density (superconductivity); electron device manufacture; grain growth; grain size; high-temperature superconductors; melting; powder technology; recrystallisation texture; strontium compounds; superconducting coils; superconducting tapes; thallium compounds; Bi substitution; Tl-1223 coils; Tl-1223 phase composition; Tl-1223 tapes; TlBi(SrBa)/sub 2/Ca/sub 2/Cu/sub 3/O; critical current densities; fabrication; grain alignment; grain growth; grain size; magnetic field properties; melt process; melt processing route; partial melt processing route; reacted powder; unreacted powder; weak link effects; Bismuth; Coils; Critical current density; Fabrication; Grain size; Lead; Magnetic fields; Melt processing; Powders; Silver;
Journal_Title :
Applied Superconductivity, IEEE Transactions on
