Kinetics of the oxidation of Ba2 YCu3Ox ceramics

Abstract

The kinetics of the oxidation of dense and porous samples of Ba2 YCu3Ox ceramic have been determined by gravimetric analysis at 400–700 °C. At 600 °C and above, the rate decreases as the thickness of the oxidized layer increases. At 500 °C and below, the kinetics show a linear relation that indicates that the oxidized layer does not protect the ceramic. Dilatometric, microscopic, and high-temperature x-ray data suggest that fractures in the oxide layer at the lower temperatures are caused by the large volume decrease that accompanies the change in oxygen stoichiometry.