Intermediate-phase-free processing of YBa2Cu3O 7-x

Abstract

A method for processing YBa2Cu3O7-x without any intermediate impurity phases has been developed. Y2O 3 and BaCO3 are reacted first to form a Y Ba4O7 complex, and CuO is forced to react simultaneously with the two cations. The (123) phase forms rapidly and directly without any intermediate phases, the reaction being completed in about 10 min at 950 degrees C. O2 atmosphere slows down the reaction. A number of combinations of time and temperature of calcination are employed to ensure that no intermediate phases are formed and that the (123) formed is stable.