Results of ITER-TF stand production at Luvata

ITER Toroidal Field (TF) coils require a large quantity of both superconductor and copper strands. Luvata has produced both Nb₃Sn and copper strands for the TF coils over the past two years under US ITER-TF and European Fusion for Energy (F4E) programs. Luvata manufactures Nb₃Sn strand via internal-tin approach with its unique wire configuration employing distributed tin spacers. Over 11,000 km of Nb₃Sn and Cu strands produced at our Waterbury, US facility were hard chrome plated by a new route using trivalent chrome. In addition approximately 13,000 km of Cr plated Cu strand was produced in our Pori facility in Finland. Tight statistical process controls (SPC) were implemented for all critical parameters during strand production. In this paper we report statistical view of all technical strand properties, namely, piece length performance, Cu/non-Cu ratio, wire diameter, chrome thickness, critical current, AC losses and RRR. (author)