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

Abstract

<para xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> Magnesium diboride <formula formulatype="inline"><tex Notation="TeX">$({\rm MgB}_{2})$</tex></formula> 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 <formula formulatype="inline"> <tex Notation="TeX">${\rm MgB}_{2}$</tex></formula> composite superconductor manufacturing technology and cryogenic technology, developing conduction cooled superconducting MRI system with <formula formulatype="inline"><tex Notation="TeX">${\rm MgB}_{2}$</tex></formula> composite superconductor is becoming increasingly feasible. An <formula formulatype="inline"><tex Notation="TeX">${\rm MgB}_{2}$</tex> </formula> superconducting magnet for MRI was developed. The <formula formulatype="inline"> <tex Notation="TeX">${\rm MgB}_{2}$</tex></formula> superconducting magnet is used to investigate the fundamental scientific problem of the MRI main magnet, including field uniformity and stability, influencing factors of <formula formulatype="inline"><tex Notation="TeX">${\rm MgB}_{2}$</tex></formula> composite superconductor on field uniformity and stability. The superconducting magnet consists of 2 solenoids wound with <formula formulatype="inline"><tex Notation="TeX">${\rm MgB}_{2}$</tex></formula> 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 <formula formulatype="inline"> <tex Notation="TeX">${\rm MgB}_{2}$</tex></formula> magnet is 290 A. The central magnetic field is 0.39 T when the current of the <formula formulatype="inline"> <tex Notation="TeX">${\rm MgB}_{2}$</tex></formula> magnet is 100 A. In this paper, main magnet for MRI with <formula formulatype="inline"><tex Notation="TeX">${\rm MgB}_{2}$</tex></formula> composite superconductor is analysed and proposed, including magnet design, test results, and field uniformity. </para>