Development of the first Tesla class iron-based superconducting coil for high field application

Abstract This study has, for the first time, combined iron-based superconductor (IBS) with high field insert coil technology to generate a higher magnetic field. Nine large-sized iron-based superconducting double pancake coils (DPCs) were fabricated, and their performance was evaluated at 4.2 K. Subsequently, seven DPCs with superior performance were assembled to form an IBS insert coil and tested at the 20 T background field. The test results indicated that the insert coil successfully generated above 1 T magnetic field under the 0 T, 10 T, and even 20 T background field, respectively. Notably, the poorest IBS DPC still had a critical current of about 84 A at the background field of 20 T, which outperformed all previously reported performance tests of IBS coils. This paper provides a detail introduction to the design and fabrication process of the IBS insert coil, presents the test results, and discusses them.