Nb-Ti superconductors of a high current-carrying capacity

The effect of multiple prolonged heat treatment on the structure and critical current density in Nb-50 wt.% Ti composites was studied in the case of monofilamentary superconductors. The treatment temperature range, in which high J c values can be obtained, is determined. The influence of intermediate treatments on the increase in the quantity of precipitated alpha -phase is studied. The exponent specifying the kinetics of particle growth from the supersaturated solid solution is estimated. The interrelation between the critical current density and the quantity of precipitated phase is established. The maximum critical current density is 4*10 5 A cm -1 (B=5 T).