A comparative study of YBCO powders prepared by different processes

摘要

Fabrication of dense ceramic samples requires homogeneous, single phase powder with a well denned particle size distribution, as the starting material. Solid state [1], coprecipitation [2], sol-gel [3], amorphous citrate [4], alkali flux [5], combus-tion [6, 7], spray drying [8], freeze drying [9] and aerosol [11] processes have been employed to prepare phase pure YBCO powder. The synthesis of ultrafine powder is required to minimize the processing parameters (time and temperature), dur-ing calcination, homogenization and sintering, so that, evaporative loss of BaO and CuO during high temperature processing [11, 12] can be avoided. So far, little effort has been made to investigate the densification behaviour of the synthesized powder to minimize the processing parameters.