| 摘要 |
PURPOSE:To increase both critical current density and mechanical strength by specifying both heating temperature and heating time respectively within specific ranges at the times of preliminary, intermediate, and final baking treatments of the mixed powder of constituents of an oxide superconductor. CONSTITUTION:Mixed powder to constitute an oxide superconductor is preliminarily baked at heating temperatures of 950 deg.C or lower. The crystal grain size of the preliminary baked object obtained can be made 10mum or smaller. The preliminary baked object is then crushed to powder and the powder is pressed to obtain a formed body of a bar shape. The formed body then undergoes an intermediate baking treatment of heating in an oxygen atmosphere at temperatures of 800-950 deg.C for 6-50hours followed by gradual cooling to obtain an intermediate baked body 1 of a bar shape. The intermediate baked body 1 is then inserted into a metallic tube 2 to form a complex body 3. The complex body 3 then undergoes a diameter reduction process with a rotary swaging device A to obtain a wire of a required diameter. The wire than undergoes a final heat treatment ot obtain a final baked body. The final heat treatment is performed under the conditions of heating in an oxygen atmosphere at temperatures of 800-950 deg.C for more than 24hours followed by gradual cooling. |
