DC behaviour of NbTi cable-in-conduit conductors for ITER-FEAT

Using the SULTAN test facility the d.c. behaviour of three subsize NbTi cable-in-conduit (CIC) conductors has been studied. The d.c. performance of the cables is compared with the critical currents and the current sharing temperatures expected from the strand data. As a basis for this comparison the critical current of the NbTi strands has been measured in the temperature range of 4.2–6.5 K in magnetic fields of up to 7.5 T. The d.c. performance of the NbTi subsize conductors has been found to be not significantly affected by cyclic loading. Taking into consideration the self field of the conductor the cable critical current and the current sharing temperature are in agreement with the strand data.