| 摘要 |
PURPOSE:To prevent production of cracks or other defects caused by the difference of thermal expansion coefficient from that of the metal pipe by filling powders of superconductive matter in the metal pipe to form a composite body, reducing the diameter of the composite body, exposing core wire of the diameter-reduced body, and heat processing it. CONSTITUTION:At least either of material powders of oxide superconductive matter or superconductive powder 2 are filled in a pipe 1 consisting of alkali- soluble metal to be a composite body 3. Then a diameter-reducing work is applied to the composite body 3 to form a diameter-reduced body 6 comprising a metal coating layer 4 consisting of the pipe 1 and a core wire 5 consisting of powders or a moulded matter. Then the metal coating layer 4 is dissolved by alkali solution to be removed from the diameter-reduced body 6 to expose the core wire 5, and a heat process is applied to the core wire 5. By thus eliminating the metal pipe 1 having a different thermal expansion coefficient from that of the core wire 5 and heat processing it, production of cracks or other defects caused by differential thermal expansion coefficient is prevented. |
