Shaped Field Magnets

Whether designing new systems or looking to boost efficiency in existing equipment, Arnold’s patented  Shaped Field Magnet (SFM) technology offers new options for designers of next-generation rotating equipment and sensor systems. By managing the magnetic field distribution, Arnold’s Shaped Field Magnets provide enhanced performance and offer greater design flexibility— often at a lower cost. Shaped Field Magnets can also replace standard permanent magnets in existing equipment, providing improved efficiency and performance.

What is a Shaped Field Magnet?

In a traditional magnet, the anisotropy within and outside a magnet is made as uniform as possible. A Shaped Field Magnet has a field with a deliberate divergence from the traditional anisotropic model. Figures 1 and 2 compare the conventional magnetic field with an SFM field arrangement. In the uniform magnetic field of a conventional magnet, a portion of the magnetic field is wasted. Whereas, in the SFM configuration, the magnetic field is shifted toward one side of the magnet, better utilizing the magnetic field.

Shaped field magnet advantages:
  • Higher field strength in the working zone for the mass and size of the magnet
  • Substitution of higher-temperature, lower-remanence materials
  • Increased design freedom, with less concern for handling stray field effects
  • Reduction of overall system weight for equipment using the SFM

Shaped Field Magnet Fabrication

Arnold’s patented process for SFM fabrication shapes the magnetic field as part of the magnet manufacturing process. The desired field shape is carefully plotted out beforehand so that the various stages of compression, sintering and magnetic field alignment work together to provide the desired field characteristic. Our quality processes and systems ensure your SFMs will perform optimally in your application.

Shaped Field Magnet Design Considerations

Know your application. Because each magnet is individually pressed, magnets must be designed for each application.
Consider your volume needs. SFM tooling requirements suggest a minimum volume of 50,000 pieces /year (for sensor magnets) or 100 kg/year (for other applications)
Take advantage of our know-how. Partner with Arnold engineering during the prototype stages in order to take full advantage of our shaped field magnet benefits.