An Actively Shielded 3T MgB2 MRI Magnet Design

Michael A. Martens¹, Tanvir Baig¹, Mihai Cara¹, Robert W. Brown¹, David Doll², Michael Tomsic²

Superconducting MRI magnets are dominantly made with NbTi wire cooled below 4.2K using liquid helium. As helium costs have more than tripled in the last decade, there is a need for a cryogen-free conduction-cooled alternative. A key reason for pursuing MgB2 superconductor wire in the design of MRI magnets is its superior critical current compared to NbTi over a temperature range of 10-15K. We present a 3T whole body actively shielded main magnet design assuming second-generation multifilament MgB2 wire using an improved functional approach. Trade-offs for the reduction of any given parameter are analyzed.