Current Transfer Length of Monofilamentary ex-situ MgB2:Al:Cu Superconducting Wire

Current transfer length (CTL) is measured for copper (Cu) sheathed and aluminum (Al) as barrier/interface material of superconducting monofilamentary MgB2 wire (MgB2:Al:Cu). The thermal stability of a superconducting wire is an important issue, which can be minimized using proper selection of sheath and barrier/interface material. CTL values perform an important act for screening of the materials used as sheath and barrier/interface. CTL values and electric field on the metallic surface of superconducting wire are calculated by employing the analytical method. In this material combination, three compositions by the respective cross-sectional area of superconducting core, barrier/interface and sheath are studied for short length wire. The study suggests that for all three cross-sectional compositions, 20: 20: 60, 20: 30: 50, and 20: 40: 40, the CTL values are nearly similar. This technique can be extended for screening of possible combinations of materials for wire fabrication, which lead to practical applications in future by the production of quality superconducting wires.