Progress in procurement for ITER superconductors

Takahashi, Yoshikazu; Isono, Takaaki; Hamada, Kazuya; Nunoya, Yoshihiko; Nabara, Yoshihiro; Matsui, Kunihiro; Hemmi, Tsutomu; Koizumi, Norikiyo; Nakajima, Hideo; Kawano, Katsumi; Oshikiri, Masayuki; Okuno, Kiyoshi

The toroidal field (TF) coil system of the International Thermonuclear Experimental Reactor (ITER) consists of 18 D-shape coils. The operating current, the maximum field and the stored magnetic energy are 68 kA, 11.8 T and about 41 GJ, respectively. NbSn cable-in-conduit conductor with a central channel is used. The superconducting cable consists of 900 NbSn strands and 522 copper strands, and they are cabled to a 5th stage cable with a central cooling spiral. The conductor manufacture started in 4 companies (strands in 2 companies, cabling, jacketing) in Japan, from March 2008. The first batches of the strands were successfully completed in 2 companies. These strands satisfy their specifications. The performance of these strands will be mainly reported.