| 摘要 |
PURPOSE:To enable production of product having arbitrary shape exact control of element amount and control of superconducting layer thickness, by blending and melting a rare earth element with alkaline earth metal and copper and forming cast alloy and then calcining the alloy in an oxidizing atmosphere. CONSTITUTION:One or more kind of rare earth element, e.g. powder of Y is blended with one or more kind of alkali earth metal, e.g. Ba powder and Cu powder at a prescribed ratio and melted and casted into a mold having arbitrary shape, e.g. 'U' shaped mold. The resultant 'U' shape Y-Ba-Cu alloy is calcined in oxidizing atmosphere and gradually oxidized from the surface to provide the aimed superconductive ceramic. O2 partial pressure in the oxidizing atmosphere is preferably about 0.02-0.2 atom and the calcining temperature is preferably about >=800 deg.C. According to the method, element ratio can be readily controlled and superconducting layer thickness from the surface can be also controlled by variously changing the oxidation conditions and can be produced into an arbitrary shape. |
