Superconducting circuit, production method of superconducting joints, superconducting magnet, and production method of superconducting magnet

摘要

A superconducting circuit including a superconducting joint that joints a niobium titanium superconducting wire having a structure where a filament made of niobium titanium alloy is arranged in a matrix made of copper or copper alloy and other superconducting wire, in which a volume ratio or a surface density of an α-Ti precipitation in the niobium titanium alloy of the filament in the superconducting joint is smaller than the volume ratio or the surface density of the α-Ti precipitation in the niobium titanium alloy of the filament in the niobium titanium superconducting wire in a portion other than the superconducting joint.