Single-core MgB2 wires were made by the powder-in-tube method using commercial Mg and B powders and 2-axial rolling deformation in FeNiCo alloy and pure Fe sheaths. Deformed wires were subjected to annealing at temperatures ranging from 500 to 750C for 0.5h in an Ar atmosphere. Resistive, R(T), and transport current, IC(B), measurements have shown how the sintering temperature influences the critical temperature and critical current densities. Strong interdiffusion and reaction especially between the Mg + B core and FeNiCo sheath was observed. This reaction was mostly responsible for the presented differences in the critical parameters of FeNiCo and iron sheathed wires.

Basic Properties of Rectangular MgB2/FeNiCo and MgB2/Fe Wires Made in situ. P.Kovác, I.Husek, T.Melisek, V.Strbík: Superconductor Science and Technology, 2005, 18, 856-60