Electromagnetic Cycling and Strain Effects on ${\rm Nb}_{3}{\rm Sn}$ Cable-in-Conduit Conductors With Variations in Cabling Design and Conduit Material Properties

A parametric study has been conducted to quantify the effect in performance of cable-in-conduit conductors (CICC´s) to changes in cable and conduit design. Measurements of current sharing temperature and critical current as a function of electromagnetic cycling and longitudinal strain were systematically performed on CICC´s with common Nb₃Sn internal tin strand. The designs varied in void fraction (0.30 or 0.36), long or short cable twist pitch, cable core patterns (6 around 1 or triplet), and conduit material property (stainless steel 316 or Haynes 242). Measurements were performed at the NHMFL in a test facility for conductor characterization with capability to 12 T, 20 kA, and 250 kN axial tensile load now modified to deliver temperature controlled supercritical helium to the CICC samples.