Development of 10 kA class Nb/sub 3/Al superconducting cable by jelly-roll process (for fusion magnets)

A multifilamentary Cu/Nb/sub 3/Al composite strand was developed with a noncopper critical current density of more than 400 A/mm/sup 2/ at 12 T, by a jelly-roll process. A 10-kA cable-in-conduit conductor was fabricated to demonstrate its applicability to fusion magnets. The cable had 324 strands, and a circular CuNi seamless pipe was used as the conduit. The strand diameter was 0.88 mm and the filament diameter was 28 mu m. The heat treatment was performed at 820 degrees C for 2 h.