Manufacturing method of precursor of MgB2 superconducting wire rod, MgB2 superconducting wire material and MgB2 superconducting wire rod

摘要

Problem to be solved: to fabricate MgB2 superconducting wire by the powder in tube method, to prevent the breaking of the metal tube containing MgB2 powder during the drawing process, and to prepare the precursor of MgB2 superconducting wire material with high critical current density after heat treatment of the raw material powder. Problem to be solved: to provide a method of manufacturing MgB2 superconducting wire and MgB2 superconducting wire using the same.The precursor of the MgB2 superconducting wire comprises a precursor region which is a filament of MgB2 and a metal tube containing a precursor region, and the precursor region is a first region in which a boron particle is dispersed in the mother phase formed of magnesium It is composed of a second region where no boron particle exists in the matrix formed by magnesium.The MgB2 superconducting wire material has a metal tube covering the filament, and the filament has a filling rate of MgB2 in the longitudinal cross section of 70% by volume or more, and the diameter of the cavity is less than 100 nm and the number density of coarse voids is larger than 500 / mm2.Diagram