Development of a high Jc bronze route Nb3Sn conductor using Nb-Ta composite filaments

For superconducting magnets generating fields above 10 tesla, multifilamentary Nb3Sn is the conductor of choice. There are two widely used methods of manufacturing these conductors, namely the internal Sn route and bronze process. Bronze route conductors can yield long piece lengths with consistent performances due to the mechanical compatibilities of the components compared to internal Sn conductors. Internal Sn designs require a soft low melting point Sn and is more difficult to be co-processed with the significantly harder Nb filaments. This paper summarizes the development of a bronze route Nb3Sn wire with high Jc using Nb-Ta composite filaments for use in advanced projects such as the International Thermonuclear Experimental Reactor (ITER)