PURPOSE: To form a good superconductive layer by forming wire lines on a metal plate in a spray coating and sintering, and moreover, applying a pressure sintering and a normalizing heat treatment after heattreating it in the ambiance including oxygen.
CONSTITUTION: Shallow grooves in a desired pattern are furnished, in which a superconductive substance is filled as a sintered substance by a plasma spray coating. In this case, the work is carried out by furnishing a masking and the like lest the sprayed material be attached. In such a way, a pattern such as a circle is drawn on a metal plate 1. Then it is heat-treated in the ambiance including oxygen, preferably in two phases, at 800 to 950°C at the beginning and at 400 to 650°C in the second phase, to increase the critical temperature Tc and to improve the superconductivity. After that, another metal plate is superposed on the metal plate 1 on which wire lines is formed of a superconductive substance, a rolling and a pressure welding are applied to improve the adhesion of both metal plates, and to make the composition of superconductive material dense. This rolling and pressure welding process is carried out in the hot or in the cold condition, and it is preferable to execute the rolling and the pressure welding process in the cold condition again after such a process.
SHIRAI KATSUYUKI
FUKIZAWA AKIRA
ASANO YUICHIRO
FUKUI KOICHIRO
SHOWA ALUMINUM CORP