| 摘要 |
PURPOSE:To improve orientability by forming the molding of the rare earth oxide superconductor in which noble metals or noble metal compds. are distributed at controlled concns., then the molding. CONSTITUTION:Raw material powders, such as Y2O3, BaO2 and CuO, are mixed at prescribed mole ratios and a small amt. of Pt powder is added and mixed to and with the raw material powders. The powder mixture is then calcined on an Ag plate in a gaseous mixture atmosphere composed of O2/N2 to form the calcined powder mixture of the rare earth oxide superconductor such as YBa2Cu3O7-x. The noble metal compd. powder, such as Ag2O, of <=20mum grain size, is mixed with the powder mixture to prepare the mixture varying on only the concn. of the Ag2O. The mixture not incorporated with the Ag2O is then molded with metallic molds and a low Ag2O-content mixture is added thereon and the mixture is molded to form a laminate. The laminate varying in layer concn. in a horizontal direction is formed by successive lamination. This laminate is heated to a prescribed temp. to the half-molten state and is then slowly cooled to allow the crystal to grow. The rare earth oxide superconductor having the high orientability is thus obtd. |
