CHARACTERIZATION OF HIGH CRITICAL-TEMPERATURE SUPERCONDUCTING WIRES

Improvements in the current transport properties of high critical temp erature superconductors would be facilitated by a quantitative descrip tion of the relationship between current capacity and superconductor m icrostructures. In this study, three types of silver-Bi2212 tapes were characterized in terms of critical current density and various micros tructural features. Tapes given melt processing treatments were found to have a higher critical current density, larger apparent Bi2212 grai n size, and stronger c-axis texture compared to the results of a lower temperature treatment. A comparison of (001) pole figure data and cur rent transport measurements indicated that a 3-fold increase in the c- axis angular spread corresponded to an order of magnitude drop in crit ical current density. (C) 1998 Elsevier Science S.A. All rights reserv ed.