Fabrication of heavily Pb-doped Bi2212 tapes

Heavily Pb-doped Bi2212 tapes were fabricated on silver and nickel substrates. On the Ag substrate, addition of fine MgO particles resulted in the increase of viscosity of the melt, and the quality of the tapes was remarkably improved due to suppression of outflow of the melt. On the Ni substrates, Bi(Pb)2212 phases were rarely formed by the conventional melt-solidification method, however, the amorphous-to-crystallization method gave a highly textured Bi(Pb)2212/NiO/Ni tape. Microstructures and superconducting properties of these tapes were investigated, The highest J/sub c/ achieved in this study was 13000A/cm/sup 2/ (30 K, OT). This J/sub c/ value, however, was still lower than that of the Pb-free tape.