Abstract
The spinodal decomposition of the YBa2Cu3O7-δ (δ≈0.2, 0.4, 0.6, 0.8) compound at temperatures of 200 and 300°C, which correspond to different regions under the spinodal curve in the YBa2Cu3O6-YBa2Cu3O7 phase diagram, has been studied using electron microscopy and optical microscopy in polarized light. It has been shown that at these temperatures the spinodal decomposition occurs, irrespective of the oxygen content (y = 6.8–6.22) in the 123 phase, via the formation of particles of the oxygen-enriched orthorhombic phase in an oxygen-depleted monolitic matrix. During annealing at 300°C, a new domain structure arises at the sites of clustering of oxygen-enriched particles, and a diamagnetic response appears in the sample.
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Original Russian Text © S.V. Sudareva, E.P. Romanov, T.P. Krinitsina, Yu.V. Blinova, E.I. Kuznetsova, 2006, published in Fizika Metallov i Metallovedenie, 2006, Vol. 102, No. 2, pp. 221–228.
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Sudareva, S.V., Romanov, E.P., Krinitsina, T.P. et al. Mechanism of phase transformations and fine structure of a nonstoichiometric compound YBa2Cu3O7-δ at temperatures of 200 and 300°C. Phys. Metals Metallogr. 102, 205–212 (2006). https://doi.org/10.1134/S0031918X06080126
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DOI: https://doi.org/10.1134/S0031918X06080126