International audienceThe unexpected degradations of current carrying capacity of Cable-In-Conduit Conductors are attributed to be mechanical in origin Nb3Sn. As a result, the prediction of conductor's performances asks for the assessment of the local strain state of the Nb3Sn superconducting strands inside cables. For this purpose, a finite element modeling, specially developed for the simulation of cable mechanics, is presented in this paper. The presented mechanical model allows simulating the conductors' service life from manufacturing to operating conditions by describing the evolution of strains and stresses within each individual strand. The distributions of axial strains within strands, obtained from simulation results of both thermal and Lorentz loadings, could help characterize the influence of design parameters

A short sample of the NbTi cable-in-conduit conductor (CICC) manufactured for the ITER PF insert coil has been tested in the SULTAN facility at CRPP. The short sample consists of two paired conductor sections, identical except for the sub-cable and outer wraps, which have been removed from one of the sections before jacketing. The test program for conductor and joint includes DC performance, cyclic load and AC loss, with a large number of voltage taps and Hall sensors for current distribution. At high operating current, the DC behavior is well below expectations, with temperature margin lower than specified in the ITER design criteria. The conductor without wraps has higher tolerance to current unbalance. The joint resistance is by far higher than targeted.Index Terms-Cable-in-conduit conductor, ITER, joint resistance, niobium-titanium, self-field induced quench.

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