Design of a Permanent Magnet with Hexagonal Cavity for Small Animal Magnetic Resonance Imaging

For the low field small animal magnetic resonance imaging (MRI) devices, the three-dimensional numerical simulations of a 1.5 T permanent magnet were performed. The 1.5 T permanent magnet has a hexagonal cavity and is considered an utmost model, transcending the limitation of the remanence of magnetic material. As an applied model, a 0.5 T permanent magnet was designed and manufactured. Compared with other yoked magnets, this hexagon magnet has two important advantages for small animal MRI. One advantage is that the magnetic density of hexagon magnet is adjacent to the residual induction of magnetic materials. The other advantage is the large usable volume that is achieved in the homogeneous magnetic field produced by hexagon magnet.