The effects of wet processing (wet milling followed by sedimentation) on the superconducting properties of YBa2Cu3O7-xpowders were investigated. Wet milling was found to result in the deterioration of the superconductivity of the oxide powders. The deterioration can be attributed to the leaching out of some constituents of the superconducting compound into the liquid medium. However, wet milling allows for the separation of the incompletely reacted compounds (minor phases) from the YBa2Cu3O7-xby classified sedimentation. During this process, the superconducting particles settle first, because they are larger, while the particles containing the minor phases sediment later, because they are smaller. The positive effect due to purification outweighs the negative effect due to leaching. In addition, an optimum milling time of 5 h was identified for improved superconducting properties.
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