DEVELOPMENT OF THE SUPERCONDUCTORS FOR ITER MAGNET SYSTEM

A review is given of the present status of the development and product ion of Nb3Sn and Nb-Ti superconductors for the Model Coils and the rea l Magnet System of the International Thermonuclear Experimental Reacto r (ITER) in the Russian Federation Home Team. It is shown that Nb3Sn b ronze processed superconductors produced for the Model Central Solenoi d Coil insert meet the ITER joint Central Team requirements. In partic ular, the critical current density, measued in non-Cu area is not less than 550 A/mm(2) for 12 T at 4.2 K, the level of hysteresis losses is not in excess of 200 mJ/cm(3), and the Cu-stabilizing shell resistivi ty ratio of Cr-plated wire is 150. Internal tin Nb3Sn superconductor d evelopment and test results are presented, confirming the possibility of their application for the ITER Magnet System winding. Nb-Ti superco nductors for PF coils properties have also been considered. The possib ility of Nb3Sn and Nb-Ti superconductor manufacture with the use of la rge composite billets up to 300 mm in dia is shown, creating the possi bility for large scale industrial production (several tens of tons/yea r) of these materials for the ITER Magnet System. (C) 1998 Elsevier Sc ience B.V. All rights reserved.