As the global helium crisis continues, the need for liquid-helium-free superconducting magnets continuously increases in the commercial sector of magnetic resonance imaging (MRI) systems. However, the conventional low temperature superconductor (LTS) magnets frequently experience unpredictable premature quenches, resulting in the extra usage of liquid helium before an MRI machine is delivered to its user site. The MgB2 technology is expected to play an increasingly prominent role in the “next generation”, mainly because of a greater thermal stability of the wires than that of their LTS counterparts, making them essentially immune to the premature quench, as well as with their liquid helium (LHe)-free feature. To date, MgB2 wires have been routinely produced by a few companies, such as Kiswire Advanced Technology that recently embarked on a collaborative R&D project with Korea University to design, construct, and operate an MgB2 MRI magnet. This study presents the design options of a 3-T/900 mm MRI magnet employing selected commercial MgB2 wires with a focus on: (1) conductor design and in-field performance; (2) coil volume and stray field; (3) mechanical stress and its tolerance; (4) cryogenic stability in various conductor options; (5) post-quench behavior and protection; and (6) field inhomogeneity due to manufacturing uncertainties of conductors.
Acknowledgement: This work was supported by the Materials and Components Technology Development Program of KEIT [10053590, Development of MgB2 wire and coil with a high critical current and long length for superconducting medical•electric power equipment].
|Submitters Country||Republic of Korea|