Title :
Local measurement of current density by magneto-optical current reconstruction in normally and overpressure processed Bi-2223 tapes
Author :
Patnaik, S. ; Feldmann, D.M. ; Polyanskii, A.A. ; Yuan, Y. ; Jiang, J. ; Cai, X.Y. ; Hellstrom, E.E. ; Larbalestier, D.C. ; Huang, Y.
Author_Institution :
Sch. of Phys. Sci., Jawaharlal Nehru Univ., New Delhi, India
fDate :
6/1/2003 12:00:00 AM
Abstract :
Magneto-optical current reconstruction has been used for detailed analysis of the local critical current density (Jc) variation in monocore Bi-2223 tapes. We find, even in high quality tapes with bulk transport jc∼40 kA/cm2 (77 K, 0 T), that there exist local regions which possess current densities of more than 200 kA/cm2. Overpressure processing at 148 bar significantly improved Jc to 48 kA/cm2 by improving the connectivity. For the overpressure-processed sample we find that the current distribution is more uniform and that the maximum local current density at 77 K is increased almost to 300 kA/cm2.
Keywords :
bismuth compounds; calcium compounds; critical current density (superconductivity); current distribution; high-temperature superconductors; lead compounds; magneto-optical effects; multifilamentary superconductors; strontium compounds; superconducting tapes; (BiPb)2Sr2Ca2Cu3O10; 148 bar; 77 K; Bi-2223 tapes; connectivity; current distribution; local critical current density; magneto-optical current reconstruction; overpressure processing; Critical current density; Current density; Current distribution; Current measurement; Density measurement; Heat treatment; Image reconstruction; Magnetic analysis; Magnetic materials; Silver;
Journal_Title :
Applied Superconductivity, IEEE Transactions on
DOI :
10.1109/TASC.2003.812056
