EMANATION THERMAL-ANALYSIS OF MICROSTRUCTURAL CHANGES DURING INTERACTIONS OF HIGH-TC SUPERCONDUCTORS WITH THE ATMOSPHERE

Emanation thermal analysis (ETA) was applied to obtain information on the microstructural changes occurring at the nanometer level during interaction of the high-T(c) superconductor, Ba2YCu3O7-x, with oxygen and hydrogen at elevated temperatures. The ETA curves in oxygen indicate differences in behavior between freshly conditioned samples and those which have been stored for several months in air. The ETA results provide valuable information additional to that obtained by traditional methods, e.g. TG, DTA and dilatometry.