抄録
The internal-tin technique is an excellent method for fabricating Nb 3 Sn superconducting wire with a high critical current density. We have developed a new type of internal-tin Nb3Sn wire in which the multi-filamentary wire is fabricated by combining mono-filamentary Nb elements and mono-filamentary Sn elements. The simple fabrication process will enable the fabrication cost of the wires to be reduced. By optimizing the spacing of the Nb 3 Sn filaments, we have obtained an internal-tin wire with high critical current density and low filament coupling. Additionally, a long wire, 5 km in length, has been fabricated, which indicates that manufacturing of mass-production-scale wires is possible using the newly developed internal-tin process.
