WIRE ROD AFFECTING ELECTRIC RESISTANCE AND CONTRIBUTING TO DEVELOPMENT OF SUPERCONDUCTIVITY BY INTERNAL PRESSURE BY THERMAL EXPANSION AND SHRINKAGE

摘要

PPROBLEM TO BE SOLVED: To provide a method, a device, and a wire rod using it in which by covering a coating substance having a thickness as capable of suppressing thermal expansion of a core wire in a low temperature state, effect to electrical resistance and superconductivity can be developed. PSOLUTION: The core wire (MgB2) is cooled (14) and a coating substance having a melting point of 420C or more is coated (8) in molten state without making eccentricity to the wire rod, and before the temperature is increased up to the inside of the core wire, it is quenched (9), and by expansion due to temperature increase of the core wire and shrinkage due to cooling of the covering material, internal pressure is generated and pressure in drawing direction of the wire can be impressed. As a method of manufacturing the core wire to be used, a means 4 of spraying on the film and rounding it, a means 7 of electrostatic adhesion, and a means of extrusion to the coating material as it is are possible, and furthermore, heat treatment and surface treatment by high frequency and laser can be applied on the wire rod. PCOPYRIGHT: (C)2006,JPO&NCIPI