Abstract
An MF superconductor with ultra-fine continuous Nb3Al filaments has been fabricated successfully by the newly developed composite process, in which a composite consisting of a niobium matrix and a large number of Al-Mg alloy cores is cold-drawn into a wire with very fine Al-Mg filaments (about 0.1μm), and then heat treated at 650-1, 000°C to form Nb3Al continuous filaments by the diffusion reaction. The wire shows Tc of 15-16K, μ0Hc2 (4.2K) of 21-23T and Jc (4.2K, 10T) of 1-1.5×105A/cm2, which are as high as those of the practical Nb3Sn multilamentary wires.
