Precursor Influence on the Electrical Properties of Textured Bi-2212 Superconductors.

Several synthetic methods, solid-state, sol-gel and polymer solution methods, have been used to prepare prereacted precursors, as well as a vitreous material obtained by melt quenching. The influence of the starting powder characteristics on the phase formation, microstructure, T and J of Bi-2212 textured rods prepared by directional crystallization from the melt has been analyzed. In all the cases, high transport critical current values (higher than 3000 A/cm at 77 K) have been obtained, independently of the precursor type. Samples obtained by the polymer route show improved T values, associated to a lower oxygen content. [ABSTRACT FROM AUTHOR]