CHARACTERIZATION OF MULTIFILAMENTARY NB3SN SUPERCONDUCTING WIRES FOR USE IN THE 45-T HYBRID MAGNET

The National High Magnetic Field Laboratory (NHMFL), in collaboration with the Francis bitter National Magnet Laboratory, is constructing a 45-T hybrid magnet system. Here we report the results of studies Co ch aracterize candidate Nb3Sn superconductors for use in the superconduct ing outsert coils. We have determined the effects of strain and magnet ic field on the critical current, measured ac losses, and measured res idual resistivity ratios (RRR). Critical currents in excess of 1000 A mm(-2) non-Cu have been measured in sample wires at 12 T and 4.2 K com bined with a hysteresis loss of less than 500 mJ cm(-3) We will also p resent predicted 1.8 K performance, based on empirical models, and wil l present a methodology for calculating sample holder prestrain.