Physico-chemical characterization of the coprecipitated Y-Ba-Cu-O fine powders

Y-Ba-Cu-O fine powders were prepared by coprecipitating in the oxalate form from metal nitrates solution. The stoichiometry of metals in the precipitate was adjusted by systematic change of copper nitrate (or yttrium nitrate) concentration for a fixed concentration of barium nitrate in the reactant. Approximately one micron size powders, with a uniform size distribution, were obtained by this new approach. This paper reports the optimum condition for calcination and sintering studied by thermal gravimetric analysis (TGA), x-ray powder diffraction (XRD) and scanning electron microscopy (SEM)