A Rutherford MgB2 cable with resistive NbTi barriers and a CuNi30 sheath

The Rutherford cable here was made of 12 single-core MgB₂ in-situ wires with an NbTi resistive barrier and a CuNi outer sheath. The uniformity of the wires and cables was analyzed using x-ray microtomography. The critical currents of the wire and cable samples were measured at 4.2 K in the outer fields from 4.0 to 8.0 T, and at 15 K–25 K in fields from 1.0 to 5.5 T. Magnetization AC losses were measured at temperatures of 20 K–40 K, external fields of 0.001–0.1 T and frequencies of 72 and 144 Hz. The obtained results show high engineering current density and reduced losses in the MgB₂ cable, which can be especially interesting for windings of superconducting motors or generators.