Precursor of MgB2 superconducting wire, and method for producing the same

摘要

An MgB 2 superconducting wire excellent in critical current density property is supplied by using a crystalline boron powder which is low in costs and easy to obtain. For the wire, a precursor of the MgB 2 superconducting wire is used, the precursor having a linear structure including a core region 2 containing a magnesium powder and a boron powder, and a sheath region 1 formed of a metal covering an outer circumferential portion of the core region. The boron powder is crystalline, and has a volume-mean particle size of 2 µm or less.