Bronze-processed Nb/sub 3/Sn multifilamentary wires for magnet systems with induction >15 T

The authors examine the problem of high field (B>14 T) critical current increase in multifilamentary Nb/sub 3/Sn bronze-processed superconductors by means of the optimization of phase forming annealing conditions and Zr, Ti, Ta, and hydrogen alloying. Optimization of phase-forming annealing conditions makes it possible to obtain multifilament nonalloyed conductors prepared by standard bronze technology with overall critical current density j/sub c/ of 2-2.5*10/sup 4/ A/cm/sup 2/ for a field of 14 T and 1-1.8*10/sup 4/ A/cm/sup 2/ for a field of 16 T. Hydrogen atmosphere heat treatment leads to a rise of j/sub c/ by 25-30% in the field of 14 T and by 50-80% in the field of 16 T. This allows the utilization of such wires in the development of magnet systems with field induction of >or=15 T.<
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