What Are Bonded Magnets Anyway?
What Are Bonded Magnets Anyway? • Bonded magnets are composites of a permanent magnetic powder(s) embedded in a non‐magnetic matrix. • The matrix is typically a thermoplastic or elastomeric binder. • Common processing techniques are extrusion, injection molding, compression bonding, and calendering. • Exhibit excellent mechanical properties compared to fully dense rare earth and ferrite magnets. • End product has good finish and dimensional tolerances requiring no finishing operations. • Injection molded magnets can be formed into complex shapes and be insert or over molded directly onto other components to produce assemblies. • The non‐magnetic binder lowers the density of the magnet and dilutes the contribution of the magnetic powder. • They generate less magnetic output per unit volume than fully dense magnets. • The two most common magnetic powders are isotropic NdFeB and hard ferrite. Neodymium Bonded Radial Ring Magnet Rare Earth Neodymium Isotropic Ring Bonded Magnet Compression Bonded Ring Magnet Bonded Ring NdFeB Magnet