Theoretical study of electrical current transport in various metal sheathed MgB2 superconducting wires

In this article, the estimation of current transfer length (CTL) and electric field of MgB2 (M) monofilamentary superconducting wires for various metals which are used as a sheath and barrier with their different crosss-ectional compositions of superconducting core/barrier/sheath are studied. Among the studied superconducting wires, the least CTL values are estimated for M/Ti/Ta (0.48 mm), M/Ti/Nb (0.51 mm) and M/Nb/Fe (0.50 mm) superconducting wires with thin barrier combinations. The estimated CTL values indicate that M/Ti/Nb and M/Nb/Fe monofilamentary superconducting wires are preferable as compared to M/Ta/Cu, M/Nb/Ni and M/Ta/Ni. The heat flux density generated on the metallic sheath is lower for the M/Ti/Nb and M/Nb/Fe superconducting wires i.e., lowest electrical dissipation as compared to the M/Ta/Cu and M/Nb/Ni superconducting wires. The lowest CTL value and heat generation make M/Ti/Nb and M/Nb/Fe a promising combination of superconducting wires for practical applications.