Procedure for the reproducible preparation of superconducting ceramic powders of YBa2Cu3Ox with high Tc and of their sintered materials

摘要

This invention is related to a reproducible method of preparation of superconducting ceramic powders of YBa2Cu3Ox (X 6.85) based on the formation of a homogeneous ceramic barbotine obtained by coprecipitation of the hydroxides of copper and yttrium in an aqueous suspension of BaCO3. This same comprises submicronic particles of the hydroxides which surround in a uniform manner those of BaCO3, thus forming a mixture with a high surface energy which, by means of calcination in air at a temperature lying between 850 degree and 950 degree for 1 to 4 hours, rapidly react with each other giving as a final product of the process a ceramic powder constituted by a single phase, YBa2Cu3Ox of orthorhombic structure and oxygen content x 6.85, which is a superconductor. These granulated and compacted ceramic powders lead, by means of sintering in air at between 900 degree and 1000 degree for 2 to 8 hours to dense bodies ( 96% of the theoretical density) with superconductor transition temperatures 84KTc92K, which can be applied as structural materials in electronic circuitry.