Rapid Calcination and Sintering of YBa2Cu3Ox Superconductor Powder Mixture in Inert Atmosphere

Abstract
The rates of forming the superconducting YBa2Cu3Ox phase during the calcination of the Y2O3, BaCO3, and CuO powder mixture at 790° and 850°C are considerably enhanced when an inert atmosphere of N2 or He is used instead of O2. Sintering in an inert atmosphere also produces higher density and larger grain size than in O2. These results are consistent with the possibility of rapid atomic diffusion in tetragonal YBa2Cu3Ox due to either high oxygen vacancy concentration or expanded lattice in an inert atmosphere.