EFFECT OF POSTANNEALING ON SUPERCONDUCTING PROPERTIES AND MICROSTRUCTURES OF BI(2212) AG TAPES/

Bi-(2212)/Ag tapes were fabricated by the melt-growth method at variou s cooling rates in air and Bi atmosphere followed by furnace cooling. Post-annealing at 810 degrees C was carried out for improving T-c and J(c). T-c of as-solidified tapes was similar to 80K, which increased t o similar to 90K after post-annealing. J(c) of as-solidified tapes was scattered even at the same fabrication condition. Post-annealing redu ced scattering of J(c) and improved J(c) of the tape with lower J(c) v alues. However, sample with high J(c) (4.2K, 0T) of 6x10(4) A/cm(2) af ter solidification was little improved by post-annealing.