PURPOSE: To obtain a large theoretical oxygen content ratio and a large theoretical density ratio and to secure high values of a critical current and a critical temperature, by blending R2O3 powder, AO powder, and CuO powder in prescribed composition and next mixing a prescribed amount of metal oxide powder for supplying short oxygen to this blended powder and next by putting/sealing the mixed powder into a metallic case to perform a firing process and providing a hot hydrostatic press (HIP) process for this metallic case to form a stuck material.

CONSTITUTION: R2O3 powder, AO powder, CuO powder, and powder of various metal oxides are prepared as raw material powder. After they are blended and mixed in respective prescribed composition ratios, a case made of Cu is filled with them at a filling rate of 50% and provided with vacuum sealing. This metallic case is fired on prescribed conditions in the atmosphere to synthesize this oxide mixed powder into superconductive ceramics. Next the case is housed in an HIP device to perform prescribed HIP processing and to form a stuck material with a specific ratio of theoretical density. In succession, cold swaging processes and cold groove rolling processes are provided respectively at plural times for this stuck material so that a conductor is manufactured. Annealing for distortion removal is also provided for this conductor.