Overview of Conductor Production for ITER Toroidal Field Magnet in Korea

The ITER toroidal field (TF) conductor is made up of superconducting Nb₃Sn and copper strands assembled into a multistage, rope-type cable inserted into a conduit of butt-welded stainless steel jacket sections. For the ITER Project, the Korean Domestic Agency (KODA) took the responsibility of the procurement of 27 superconducting conductors for the ITER TF magnets. After concluding the Procurement Arrangement (PA) with the ITER International Organization in May 2008, KODA has been implementing the PA through four major industrial contracts: (1) Nb₃Sn strand, (2) cable, (3) stainless steel jacket sections, and (4) jacketing. Prior to the production of conductors required for the TF coils, one 760-m-long copper dummy conductor and one 100-m-long superconducting conductor were fabricated for manufacturing process qualification. As of June 2013, 16 TF conductors were successfully manufactured. The full-size conductor performance tests in the SULTAN facility yielded very high performance. This article describes the technical requirements of the TF conductor and how KODA has been manufacturing the conductors with a high-level quality assurance/quality control system. It also presents the results of acceptance tests, including those of the SULTAN test.