In order for the next generation high energy physics particle accelerators to reach higher collision energy levels, there is a need for higher field dipole magnets. This in turn demands superconductors that have higher critical current densities in the presence of high magnetic fields, than can be typically reached with the best materials available today. Nb₃Sn conductors are the most promising material for the next generation of dipole magnets with fields $15 Tesla; however further improvements are necessary. This project will develop a high critical-current-density Nb₃Sn conductor pro-duced by the powder-in-tube (PIT) method, with tantalum and titanium additions used to improve the upper critical field and high field critical current density. Phase I produced NbSn₂ powder for use in the PIT process. Tantalum- and titanium-doped niobium tubes were produced by wrapping thin layers of sheets around a removable core and using hot extrusion to bond the components together. Finally, billet assembly and drawing techniques were established to produce multifilamentary composites. Phase II will further improve the PIT process by improving NbSn₂ powder homogeneity and reducing maximum particle size. The powders will be used to produce multifilamentary composites with final filament diameters between 40-100 microns. Finally, heat treatment studies will be conducted to improve the critical current density of the Ta- and Ti-doped samples.

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