Development of High Current Density Nb3Sn Conductor with Distributed Tin Configuration

Next generation high‐energy accelerators, (VLHC for example), require magnets in the range of 10 to 12T. It is necessary to use Nb3Sn conductor with current density over 2000 A/mm2@12T for these magnets. Increase of current density can be still done by the reduction of unnecessary bronze portion of the conductor and uniform synthesis of Nb3Sn. Through the optimization consideration using finite element analysis. we have introduced new configurations of niobium and tin. FIT (filament in Tube) and DT (Distributed Tin) method were tried and the DT method gave a very good result. The current density of DT conductor reached 2120 A/mm2 @ 12T. The critical field of DT conductor appeared to be high even it is cured at low temperature to suppress the grain size growth.