Superconducting properties of wires based on NbTi and NbTiTa alloys at 2 K and 4.2 K

Comparative investigations of superconducting properties at 4.2 and 2 Kelvin are presented for NbTi and NbTiTa wires manufactured by identical heat treatments. Three NbTiTa alloys with 12.4; 14.0 and 20.4 wt% Ta have been studied in this work. Single and double stacked wires with filament diameter from 20 to 3 /spl mu/m are under the consideration. An attempt to optimize critical current density for high field application is described.