Fabrication and properties of multifilamentary MgB2 wires by in-situ powder-in-tube process

Abstract We have fabricated the long TiC-doped MgB 2 wires with 6 filaments by in-situ powder-in-tube method using Nb as the barrier and copper as the stabilizer. To improve the strength of wires, the Nb-core was used as the central filament. The transport engineering critical current density ( J ce ) of the samples sintered at different temperature were measured, which reaches 2.5 × 10 4  A/cm 2 at 4.2 K, 5 T. 100 m MgB 2 wires with different diameter were wound into coils and the transport critical current ( I c ) of the coil were measured at 30 K in self-field. The J ce value 100 m coil achieves 1.1 × 10 4  A/cm 2 in 1.2 mm wire. The reasons leading to the enhancement of high field J ce were discussed. The results show a good potential to fabricate high performance MgB 2 wires and tapes at ambient pressure on an industrial scale.