| 摘要 |
PURPOSE:To obtain a superconducting substance having improved tailing phenomenon, by pulverizing and forming a calcined powdery mixture of raw materials for a superconducting substance and sintering the formed article at a specific heating rate. CONSTITUTION:Prescribed powdery raw materials for a superconducting substance are mixed, calcined, pulverized and formed. The formed product is sintered and cooled to obtain a superconducting substance. In the above process, the heating of the sintering material is carried out by raising the temperature slowly up to 300 deg.C and then quickly heating the material to obtain the objective superconducting substance. A large amount of moisture contained in the calcined powder can be smoothly removed in sintering operation by the above heating pattern and, accordingly, the superconducting characteristics, above all the tailing phenomenon can be extremely shortened or completely eliminated. The slow heating in the above process means the heating rate to inhibit the abrupt evaporation of a large amount of water and is usually 50-200 deg.C/hr. |
