Test of the NaAl insert and ITER central solenoid model coil

Abstract

The Central Solenoid Model Coil (CSMC) was designed and built by an ITER collaboration in 1993-2001. Three heavily instrumented Inserts have been also built for testing in the background field of the CSMC. The Nb 3 Al Insert was designed and built by Japan to explore the feasibility of an alternative to Nb 3 Sn superconductor for fusion magnets. The Nb 3 Al Insert coil was tested in the CSMC Test Facility at the Japan Atomic Energy Research Institute, Naka, Japan in March-May 2002. It was the third Insert tested in this facility under this program. The Nb 3 Al Insert coil was charged successfully without training in the background field of the CSMC to the design current of 46 kA at 13 T peak field and later was successfully charged up to 60 kA in 12.5 T field. This paper presents the test results overview.

Superconducting materials for large scale applications

“…This step is followed by drawing, hexing, and restacking into the final composite with a Cu matrix, which is then drawn to final size and reacted to form Nb Al. Sumitomo Electric Industries, Osaka, Japan, has used this approach to manufacture several tons of wire for a model coil for the ITER project; so manufacturability has been demonstrated [53]. However, the Nb Al layer formed by this diffusion step is off-stoichiometry, and both and are suppressed.…”

Future Accelerator Magnet Needs

“…Programs in Japan are actively developing processing techniques for this material [11], [12]. Optimization of a process developed by the National Institute for Materials Science (NIMS), has resulted in a steady increase of , , and [13].…”

Superconducting magnet system in a fusion reactor

“…One ton of Nb 3 Al strand with high copper ratio was successfully produced at the middle of 1990s [19]. The Nb 3 Al insert [20] was then fabricated using this strand and tested at JAERI by installing in the bore of the CS model coil as was done for the other inserts. Table 4 shows major parameters of the Nb 3 Al insert.…”