| 摘要 |
PURPOSE:To form an oxide superconducting material exhibiting superconducting characteristics even when oxygen is not satisfactorily absorbed in the material during sintering, by providing a specified compsn. CONSTITUTION:This oxide superconducting material has a compsn. represented by a formula CaxR1-xBa2Cu3O7-delta (where R is at least one kind of metal selected among Y and lanthanoids, 0.4<x<0.6 and 0<delta<1). The superconducting material may be obtd. by uniformly mixing compds. of the constituent elements such as oxides, salts or alkoxides in a prescribed ratio, drying and sintering the mixture. At this time, in order to allow a solid phase reaction to proceed satisfactorily, the powdery mixture is preferably press-molded and sintered in the form of pellets. The pref. sintering temp. is 920-940 deg.C. It is not especially required to slowly cool the sintered material and this material may be rapidly cooled by putting in liq. nitrogen after calcining. |
