Development of Pre-Bent High-Strength ${\rm Nb}_{3}{\rm Sn}$ Cable With Stainless-Steel Reinforcement Strands

A 7-strand Nb₃Sn superconducting cable, which consists of three pre-bent CuNb/Nb₃Sn strands, three stainless-steel (SS) strands, and a center SS strand, was fabricated. 2.5 turns of the cable was wound on a 262-mm diameter GFRP bobbin A triplet consisting of three pre-bent CuNb/Nb₃Sn strands was also tested for comparison. The reinforcement effect of stainless-steel strands in a cable was investigated to develop a high-strength large-current superconducting cable. The hoop stress test result indicated that the stainless-steel reinforced CuNb/Nb₃Sn cable showed better performance than the CuNb/Nb₃Sn triplet under the hoop stress, because the stainless-steel strands reduced the hoop stress on Nb₃Sn strands. Furthermore, the solder impregnation of the cable, which made the seven strands a monolithic conductor, improved its performance.