Development of Nb/sub 3/Al cable-in-conduit fusion superconductors

The present status of Nb/sub 3/Al cable-in-conduit conductor development is described. Nb/sub 3/Al cable-in-conduit conductors have been developed for application to the International Thermonuclear Experimental Reactor (ITER) magnet. Several conductors were fabricated having a full size and a sub-size with current capacity of 5-40 kA at 11.2 T. Their performance was examined by critical current and mechanical property tests. The full-size 40 kA-11.2 T conductor consisted of 324 Nb/sub 3/Al strands inserted in a CuNi conduit. The Nb/sub 3/Al strands were made by the Jelly Roll process and had a diameter of 1.22 mm and a copper ratio of 2. The non-copper current density was over 600 A/mm/sup 2/ at 11.2 T and 4.2 K. The effective filament diameter was less than 20 mu m.>