Development of recipes and methods for the fabrication of Nb3Sn multifilamentary wires with enhanced current carrying capabilities (Nb3Sn wire development) (WireDev)
The collaboration aims to develop recipes and methods for the fabrication of Nb3Sn multifilamentary wires with enhanced current carrying capabilities. It is to implement the internal oxidation technique for increasing the critical current density Jc, combined with a conventional Ta or Ti doping of Nb3Sn for enhancing the upper critical field Bc2. As Jc in Nb3Sn is proportional to the grain boundary density, the idea behind the internal oxidation technique is to form a dispersion of oxide nanoinclusions to refine the grain size of the superconductor down to about 50 nm, i.e. two to three times smaller compared to that of state-of-the-art conductors, leading to a consequent increase of Jc. In order to be suitable for accelerator magnets, the prototype wires developed in this project will have to meet some other essential requirements beyond the high Jc: good thermal stability, tolerance to mechanical loads, a low superconducting filament size to reduce magnetization. Moreover, the wire fabrication routes must be scalable at industrial level.