Research on ${\rm MgB}_{2}$ Superconducting Magnet With Iron Core for MRI

Magnesium diboride $({\rm MgB}_{2})$ shows a wide application prospect in the field of low field DC application for its relatively simple structure and rather higher critical temperature than LTS. With the development of ${\rm MgB}_{2}$ composite superconductor manufacturing technology and cryogenic technology, developing conduction cooled superconducting MRI system with ${\rm MgB}_{2}$ composite superconductor is becoming increasingly feasible. An ${\rm MgB}_{2}$ superconducting magnet for MRI was developed. The ${\rm MgB}_{2}$ superconducting magnet is used to investigate the fundamental scientific problem of the MRI main magnet, including field uniformity and stability, influencing factors of ${\rm MgB}_{2}$ composite superconductor on field uniformity and stability. The superconducting magnet consists of 2 solenoids wound with ${\rm MgB}_{2}$ wire with the length of 60 m. The magnet has an outer diameter of 169 mm, an iron core diameter of 135 mm, and air gap of 32 mm. The superconducting magnet is fabricated and tested. The central magnetic field reaches 1.0 T when the current of the ${\rm MgB}_{2}$ magnet is 290 A. The central magnetic field is 0.39 T when the current of the ${\rm MgB}_{2}$ magnet is 100 A. In this paper, main magnet for MRI with ${\rm MgB}_{2}$ composite superconductor is analysed and proposed, including magnet design, test results, and field uniformity.