| 摘要 |
PURPOSE:To prevent the release of oxygen from the outer periphery and obtain an oxide superconductor with little aging change and high reliability by baking gradually from the vicinity of a through hole toward the periphery and adjusting the temperature and feed time of the oxidation accelerating gas to leave the outer periphery unbaked. CONSTITUTION:The heated oxygen gas is fed into a through hole 27 provided on an oxide superconductor 26 prior to the main baking to heat the inner wall of the through hole 27 for the baking reaction. The superconductor exists in the range of x0<=x<=x2 on the axis (x), for example, the temperature is the baking optimum temperature near x0, but the temperature is decreased near x2 and becomes the temperature at the lower limit or lower of the baking temperature at which superconductivity appears. The range of x2<=x<=x1 is not a superconducting layer capable of attaining the superconducting state but an insulating layer 28 unable to attain the superconducting state. When a barrier such as the insulating layer 28 is provided on the outer periphery of the superconductor 26, such a state rarely occurs that the superconductor 26 is deprived of oxygen and deoxidized, and the aging change of the superconducting characteristic is decreased. |
