Development of 46-kA Nb/sub 3/Sn conductor joint for ITER Model Coils

Author

Takahashi, Y. ; Nunoya, Y. ; Nishijima, G. ; Koizumi, N. ; Matsui, K. ; Ando, T. ; Hiyama, T. ; Nakajima, H. ; Kato, T. ; Isono, T. ; Sugimoto, M. ; Kawano, K. ; Oshikiri, M. ; Seki, S. ; Wakabayashi, H. ; Takano, K. ; Uno, Y. ; Nakamura, T. ; Tsuji, H. ;

Author_Institution

Naka Fusion Res. Establ., JAERI, Ibaraki, Japan

Volume

10

Issue

1

fYear

2000

fDate

3/1/2000 12:00:00 AM

Firstpage

580

Lastpage

583

Abstract

The conductor joint is one of the key technologies for superconducting coils. A butt type joint has been successfully developed for the ITER magnets. The 46 kA Nb/sub 3/Sn conductors are connected by the diffusion bonding technique in vacuum, after the reaction of Nb/sub 3/Sn. The advantage of this joint is low losses against pulse field, because the compacted part is very small compared with other types of joint. 15 butt joints have already been fabricated in the ITER CS Model Coil. According to the test results of the full-size conductor samples, these butt joints will be operated stably in the pulse operation, because the temperature increase due to ac losses and Joule heating by joint resistance is very small and the joint has a sufficiently high temperature margin.

Keywords

Tokamak devices; fusion reactor design; niobium alloys; superconducting coils; tin alloys; 46 kA; ITER; Joule heating; Model Coils; Nb/sub 3/Sn; Nb/sub 3/Sn conductor joint; ac losses; butt type joint; diffusion bonding; joint resistance; temperature; Conductors; Diffusion bonding; Magnets; Niobium; Resistance heating; Superconducting coils; Temperature; Testing; Tin; Vacuum technology;

fLanguage

English

Journal_Title

Applied Superconductivity, IEEE Transactions on

Publisher

ieee

ISSN

1051-8223

Type

jour

DOI

10.1109/77.828301

Filename

828301