Performance Investigation of a New Developed High-Jc Nb3Sn Superconducting Strand

The magnet system of 14 $T$ magnetic resonance imaging (MRI) is under design at Institute of Plasma Physics Chinses Academy of Sciences (ASIPP), Hefei, China. In the latest design, the maximum magnetic induction field of the magnet system is 14.3 T. High performance Nb3Sn strand is the best candidate superconducting material to build such high field magnet device. To meet the requirement, ASIPP and Western Superconducting Technologies Company (WST) are cooperating to develop high performance Nb3Sn strand, the critical current density J c is higher than 2000A/mm2 at 4.2 K, 12 T. To study WST high performance Nb3Sn strand, the critical current Ic or quench current was measured at different field using the voltage-current (V-I) method. Besides, the residual resistivity ratio (RRR) were also measured. Furthermore, a small coil was designed and fabricated to study the strand whether it will be affected by low field instability. The preliminary investigation is presented and discussed in here.