Study of the Superconducting and Thermal Properties of ex situ GlidCop-Sheathed Practical Conductors

In dc and ac practical applications of MgB₂ superconducting wires, an important role is represented by the material sheath that has to provide, among other things, a suitable electrical and thermal stabilization. One way to obtain a large-enough amount of low-resistivity material into the conductor architecture is to use it as the external sheath. In this paper, we study ex situ multifilamentary MgB₂ wires fabricated with oxide-dispersion-strengthened copper (GlidCop) as the external sheath in order to reach a good compromise between critical current density and thermal properties. We prepared three GlidCop samples with different contents of dispersed submicroscopic Al₂O₃ particles. We characterized the superconducting and thermal properties, and we showed that the good thermal conductivity, together with the good mechanical properties and a reasonable critical current density, makes the GlidCop composite wire a useful conductor for applications where high thermal conductivity is required at temperatures above 30 K, such as superconducting fault-current limiters.