"Progress in Iron-Based High-Field Superconducting Magnet Technology" Selected as One of the Top 10 Highlights of the Steady High Magnetic Field Experimental Facility in 2024 (2025-06-09)

On May 23rd, the 2025 User Committee Meeting of the Steady High Magnetic Field Facility (SHMFF) was held at the High Magnetic Field Laboratory, Chinese Academy of Sciences. The research progress on iron-based superconducting magnet technology by Xu Qingjin's team from the Institute of High Energy Physics, "Development of metal-insulated iron-based superconducting coils and charging tests under high magnetic fields up to 32 T, Supercond. Sci. Technol. 37 (2024)", received high recognition from the user committee. It was evaluated as a representative work "from basic research to application transformation" and was selected as one of the top 10 highlights of SHMFF in 2024.

Iron-based superconductors have characteristics such as high upper critical magnetic field (>100 T) and small anisotropy. Since their preparation process does not require oxygen permeation or coating, they are expected to more easily achieve large-scale batch production of a new generation of high-temperature superconducting materials with low cost and excellent mechanical properties, showing transformative application prospects in the field of high magnetic fields. Since 2018, the High-Field Superconducting Magnet Team of the Institute of High Energy Physics has closely cooperated with the Iron-Based Superconducting Materials Team of the Institute of Electrical Engineering to carry out the development and high-field performance testing of iron-based superconducting cables and experimental coils of different sizes/types. Among them, the high-field inserted iron-based double-pancake coils and series coils completed critical current performance tests under background magnetic fields of up to 32 T and 35 T at the High Magnetic Field Laboratory, Chinese Academy of Sciences. This is the first international experimental study on superconducting and current-carrying characteristics of iron-based coils above 30 T. The coils achieved a maximum stable current of 60 A at 32 T, confirming the feasibility and potential superiority of the new generation of iron-based high-field superconducting magnet technology. Additionally, the developed large-current transposed cable based on iron-based superconducting tapes achieved a critical current exceeding 7 kA at 4.2 K, filling an important gap in the realization of iron-based high-field superconducting magnet technology.

Compared with copper-based superconducting materials, iron-based superconductors were discovered 22 years later. However, in the past decade or so of development, they have successfully transformed from basic research into practical superconducting materials, with the latest core parameters reaching levels comparable to copper-based superconductors. With the further improvement of iron-based superconducting material performance and the deepening of iron-based superconducting application research, the new generation of low-cost high-field superconducting magnet technology is expected to enter practical application in the near future, serving the needs of China's large-scale scientific facilities and the main economic battlefield.

This research was supported by the National Key Research and Development Program project "Next-Generation High-Field Magnet Technology and Verification Based on Iron-Based Superconductors" and the Chinese Academy of Sciences B-type Strategic Priority Research Program "Key Science and Technology of Next-Generation High-Field Superconducting Magnets".

Award Ceremony for the Top 10 Highlights of SHMFF in 2024