TG-DTA Study on the High <i>T</i>_c Superconductor YBa₂Cu₃O_<i>x</i> Ceramics

Abstract

Thermal analysis of superconducting YBa2Cu3Ox ceramics was studied by TG-DTA between 25•‹ and 900•Ž. The weight loss due to release of structural oxygen was 1.5%, 1.3% and 2.0% in air, oxygen and nitrogen, respectively. The YBa2Cu3Ox ceramics absorbed oxygen rapidly around 330•Ž. Change of oxygen content of this compound was reversible under the cycle of heat treatment in oxygen containing atmospheres. The phase transition from orthorhombic to tetragonal structure occurred at 570•Ž in nitrogen, 620•Ž in air and 680•Ž in oxygen atmospheres.