Thermoanalytical Studies on Preparation Conditions of Superconducting YBa2Cu3O7-y
- 1 March 1989
- journal article
- Published by IOP Publishing in Japanese Journal of Applied Physics
- Vol. 28 (3R)
- https://doi.org/10.1143/jjap.28.341
Abstract
We studied the decarbonation process of a ternary mixture of Y2O3, BaCO3 and CuO or Cu2O by TG-DTA analysis to clarify the optimum condition for the preparation of YBa2Cu3O7-y ceramics, which are superconducting above 90 K. We found that a narrow temperature region, 940∼950°C, is desirable for the decarbonation process. Furthermore, we observed an anomaly at ∼600°C in DTA curves of stoichiometric YBa2Cu3O7-y ceramics and nonstoichiometric Y–Ba–Cu–O samples. From the strong correlation between the magnitude of this anomaly and the composition of the ceramics, the anomaly was attributed to the orthorhombic-tetragonal phase transition in the YBa2Cu3O7-y phase. It was also found that the composition dependence of T c of the ceramics correlates strongly with that of the magnitude of the anomaly.Keywords
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