Study of Nb3Sn strand with enhanced characteristics for ITER

The results of the study of perspective Nb3Sn strands of new layout, which can be used for ITER-FEAT magnetic system, are presented. A new approach al lowed to provide more uniform distribution of superconducting filaments in the strand cross-section. These strands, made by the bronze route, contain 7600 filaments artificially doped with titanium. The external Cu stabilizer is separated from the bronze/filament matrix by a Ta/Nb diffusion barrier. The properties of the superconductor meet the new ITER specifications. The critical current density of the strands (0.7-0.8 mm in diameter) at 12 T a nd 4.2K, is above 700 A/mm(2) while the hysteresis loss is lower than 190 m J/cm(3) at +/- 3T.