The heart of the ITER Tokomak is the toroidal field magnet system made up of 18 superconducting coils.  Each coil is wound from Cable-In-Conduit Conductors which consist of 900 Nb3Sn-based superconducting strands mixed with 522 pure copper strands, formed into a rope-type cable that is inserted into a circular stainless steel jacket.  The conductors, which are cooled by a forced flow of critical helium, are designed to transport 68 kA in a peak field of 11.8 T.

In total, the TF coils require 88 km of conductors whose in-kind procurement is shared among six Domestic Agencies (DA): China, Europe, Japan, Korea, the Russian Federation and the US. The Japanese-DA was the first Domestic Agency to sign a Procurement Arrangement with ITER Organization on 28 November 2007, and this was for its 25% share of the TF conductor.

In March 2009, it was reported in Newsline that Japan had completed the production of its first batch of Nb3Sn-based superconducting strands  and last April, Newsline reported that Japan had completed the manufacture of its first conductor unit lengths to be used for TF coil trial winding. 

On 20 June 2010, the ITER Organization approved a Credit Request submitted by JA-DA for a total amount of 7.82 kIUA, corresponding to 12.14 millions euros. 

The Credit Request encompasses the order of 17 tons of Nb3Sn-based strands, 2.4 km of superconducting cables and one 760 m long copper dummy conductor. This material, produced by Japanese suppliers selected by JAEA, has successfully undergone all required quality control tests. 

The results of these tests were inputted by the suppliers into the Conductor Database developed by the IO and were verified and cleared at regular intervals by the DA and the IO according to the Control Points defined in the Procurement Arrangement. 

In total, the acceptance of this material required the clearance of 318 Authorization-To-Proceed Points by JAEA (308 for strands and 10 for cables) and one Conductor Hold Point by the IO.

This Credit Request is the first for actual hardware being produced within the framework of industrial contracts for ITER and that will be used for components installed in the Tokamak.  It confirms the leading role played by JAEA in ITER conductor production. It is also a good example of how tight collaboration between personnel at IO and the DA can drive the project and lead to significant accomplishments.