P.E. Kazin, V.V. Poltavets, M.S. Kuznetsov, D.D. Zaytsev, Yu.D. Tretyakov, M.Jansen, M.Schreyer
Supercond. Sci. Technol., v. 11, p. 880-886 (1998)
ABSTRACT. Chemical compatibility of Sr1-xCaxIn2O4 phase with Bi2Sr2CaCu2O8+x was investigated, and Bi-2212/Sr1-xCaxIn2O4 composite superconductor was prepared. The ceramic processing of corresponding oxide and carbonate mixture at 860oC led to two phase species: Sr0.55Ca0.45In2O4+Bi-2212, while solubility of In in Bi-2212 was less than 5 mol %. At 900oC indium appeared to be less soluble in the BSCCO melt, instead concentrated in fine grains of Sr1-xCaxIn2O4 phase suspended in the liquid. By slow melt crystallization Bi-2212/Sr1-xCaxIn2O4 composite was obtained. The In-rich phase formed micron sized rods which were both randomly imbedded in Bi-2212 lamellas and agglomerated on the Bi-2212 grain boundaries. The presence of indium surplus did not prevent Bi-2212 phase formation and grain growth and had minor effect on Tc of the superconductor.
Laboratory of Inorganic Material Science