The TFCI Conductor Examination in LIS-12 Facility

The toroidal field conductor insert (TFCI), a single layer coil wound from the Nb₃Sn CICC intended for the ITER toroidal field coil, was tested in October 2001 at the JAERI test facility (Naka, Japan) as part of the ITER CSMC & Insert Test Program. During the test campaign the TFCI reached a design operating current of 46 kA at a background magnetic field of 13 T without any problem. Similar to all recently tested Nb₃Sn CICC the current sharing temperature T_cs of the TFCI conductor was found to be 0.8-1.0 K lower than expected. To determine the origin of this effect the manufacturing company (the D.V. Efremov Scientific Research Institute of Electrophysical Apparatus (NIIEFA)) performed the destructive examination of TFCI. No deviations from design specification were found. A length of conductor was extracted from the TFCI winding and tested in the LIS-12 facility. The number of strands were traced inside the cable and connected individually to power supply. The strand performance was inspected at 0-10 T background magnetic field and 4.2-20 K temperature. The paper describes the specimen layout and test set-ups, presents first results of measurements along with preliminary analysis.