| 摘要 |
PURPOSE:To increase superconductive transition temperature by providing an oxide superconducting material, containing Tl, Sr, Cu and one or more rare earth elements at >=2 ratio of Sr/rare earth element and having a crystal structure belonging to the tetragonal system with specific lattice constants. CONSTITUTION:An oxide of a rare earth element Ln, such as Tl2O3, SrCO3 or Y2O3, and CuO powder, etc., are used and mixed so as to provide >=2, preferably 5 to 10 ratio of Sr/Ln. The resultant mixture is then pulverized and mixed in a dispersion medium, such as ethanol, for about 1hr. The obtained mixture is further dried at about 120 deg.C to afford powder, which is then calcined at about 1000 deg.C for about 5hr, subsequently pulverized and dried to provide a Tl-Sr-Ln-CuO-based oxide superconducting material, having a crystal structure with lattice constants of (a)=0.38nm and (c)=1.22nm and belonging to the tetragonal system. |
