Magnete und Handel

Plastic bonded magnets

In addition to these magnets, Tridelta also offers flexible magnetic rubber.

Plastic-bonded magnets can be manufactured to precise final dimensions with tight geometric tolerances without cost-intensive post-processing. A wide range of shaping options allow new technical solutions due to the enormous design freedom.


  • production accurate to final dimensions
  • high variety of shapes
  • good corrosion resistance


Excerpt from the numerous applications:

  • Sealing lips eg for refrigerators and showers
  • Magnetic boards/display boards
  • Advertising foils, magnetic signs
  • Toys, electronics and sensors
  • Automobile production
  • Automation
  • Communication Technology
  • in machine tools for the control of magnetic switches
  • Position detection, angle or path length measurements
  • Household appliances
  • Electrical industry

Magic production

Plastic bonded magnets are manufactured by a pressing process in which the alloy powder is mixed with synthetic resin, pressed, and then heated at approximately 150°C. Thanks to a special process, high filler contents with good mechanical strength are achieved despite the very low plastic content.

Another way to produce plastic-bonded magnets is to compound the powder with plastics and then spray it on. In this process, the heat treatment process is skipped. In casting, the magnetic powder is mixed in a container and poured like plastic. This manufacturing process can incur high tooling costs, but allows for intricate shapes and tight tolerances. Compared to sintered magnets, the magnetic values are lower with this process.

Finally, a coating can be applied as corrosion protection in both processes.

The extrusion press allows unlimited magnet lengths. However, the energy product of flexible magnets is inferior to sintered magnets.

Magnetic shapes

For pressed magnets, all manufacturable shapes can be realized: cuboids, cylinders, rings, segments and other molded parts are available. Holes, recesses, grooves, etc. can also be made if they run parallel to the pressing direction.

All injection-moldable shapes can be produced for injection-molded magnets. The dimensional tolerances achievable here are very tight, so that reworking is not necessary. For example, shafts can be pressed into tightly toleranced bores. With this magnet molding process, it is also possible to use foreign parts such as magnetic recess parts, etc.

Temperature behavior

As with the pure material types, temperature influences on plastic-bonded magnets also lead to a change in magnetic behavior depending on the magnet material.

The maximum operating temperature also depends on the magnet material and the binder used.

Chemical and mechanical properties

The chemical and mechanical properties are determined by the plastic selection and the plastic content. The density depends on the degree of filling. As the mechanical strength essentially determines the plastic framework, a low plastic content with a higher magnetic powder content is equivalent to low strengths with high residual magnetizations. Depending on the shape, a compromise must often be found between magnetic and mechanical values.

Magnetic properties

Plastic-bonded magnets have lower magnetic values than the pure material grades with which they are mixed, but in some cases have significantly broader shaping possibilities. In addition, filler orientation and filler content also influence the magnetic properties.

[Tabellen-ID /]

1) Description based on DIN 17410/IEC 60404-8-1
2) The maximum possible operating temperature depends on the dimensioning of the system.
i = (injection) injected, p = (pressed) pressed, hard ferrite 11/22 p and Neolit sp 445 = anisotropic