Bonded magnets are a type of composite material created by embedding magnetic powder within a binder matrix. They are renowned for their superior performance consistency, ability to form complex shapes, high dimensional precision, elimination of the need for subsequent mechanical machining, integration capabilities with other functional components, and suitability for mass production. The magnetic powder, volume fraction of the binder, and internal porosity play critical roles in determining the magnetic and mechanical properties of bonded magnets.
Isotropic Neodymium magnets dominate the bonded rare earth magnet market, accounting for over 80% of the market share. The remaining 20% is shared among anisotropic Neodymium magnets, SmFeN magnets, anisotropic SmCo magnets, and hybrid magnets. In addition to a variety of magnetic powders, different types of binders contribute further diversity to bonded magnets. Commonly used binders include thermosetting and thermoplastic materials, which correspond to processes such as compression molding, injection molding, extrusion molding, and calendering molding.
