Precursor influence on the electrical properties of textured Bi-2212 superconductors

Abstract

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, Tc and J c 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/cm2 at 77 K) have been obtained, independently of the precursor type. Samples obtained by the polymer route show improved Tc values, associated to a lower oxygen content. © Springer Science+Business Media, LLC 2010.