POWDER SYNTHESIS AND FABRICATION OF AG-SHEATHED BI-2223 TAPES

An alternate processing route is described for the production of unifo rm, fine-grained precursor mixture for the fabrication of Bi-2223 tape s. The precursor powder was produced by aerosol spray pyrolysis of nit rate salts. It was found that the phase content of the powder is sensi tive to several processing parameters including temperature and oxygen partial pressure. Bi-2223 tapes were manufactured using these powders by a powder-in-tube method. Supereonducting properties of these tapes are presented. A novel nondestructive transmission x-ray diffraction study showed that the texturing process of the superconducting phase i s nearly complete by the end of very early stage of heat treatment. Pr essing was found to play little rote for the texturing process.