| 摘要 |
PURPOSE:To obtain the Tl system oxide superconductor having >=112-118K Tc by mixing a Ba compd. and Cu compd. with Tl2O3 and CaO at prescribed ratios and molding the mixture, then calcining the molding in an oxygen-contg. atmosphere. CONSTITUTION:The Tl2O3, CaO, Ba compd., and Cu compd. are so mixed that the ratios of Tl:Ba:Ca:Cu attain 2:2:2:3 or 2:1:2:3. The mixture is preferably subjected to a low temp. calcination treatment at 870-890 deg.C in the gaseous oxygen atmosphere so that the unnecessary components are previously removed therefrom if the unnecessary components such as carbon exists in the mixture. The powder mixture prepd. in such a manner is subjected to a compaction treatment under, for example, about 0.1-10t/cm<2> pressure exerted thereto. The resultant molding is treated for 0.1-10 hours at 870-890 deg.C in the gaseous oxygen atmosphere, by which the superconductor having the compsn. Tl2Ba2Ca2 Cu2Ox (Tc=118K) or Tl2Ba2Ca1Cu3Ox (Tc=112K) of high Tc is obtd. |
