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The field dependences of the critical current density of the HTSC compound YBa 2 Cu 3 O y recov ered at T = 920-950°C after the low temperature treatment have been investigated. At T = 200°C, structural defects are formed in a wet environment, which are capable of initiating pinning of magnetic vortices. A short term (1-3 h) recovery annealing performed at T = 930-950°C leaves in the samples a fairly large amount of structural defects formed during the low temperature treatment, which results in a substantial increase in the critical current density in magnetic fields of ~2 T as compared to the ceramics not subjected to double annealing. A longer high temperature treatment removes the structural defects formed and brings the electrophysical properties of YBa 2 Cu 3 O y to the level characteristic of the ceramics produced by standard technology.

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