Bonded Magnets

Bonded magnets are made by two main methods both of which use powdered magnetic material as the sorce component. One technique produces an injection moulded part while the other produces a pressed part bonded together by epoxy.

There are several key points which should be noted about these bonded materials:

1. Their magnetic performance will be linked to the base magnetic powder that was used to make the magnet however as the magnets are not fully dense the properties will be lower than those of the corresponding sintered magnet.
2. The plastic or epoxy used to make the magnets will limit their maximum operating temperature which may be lower than the maximum operating temperature of the base magnetic material.
3. The mechanical properties of the injection moulded parts are not the same as those of the base polymer from which they were produced.
4. Compression bonded magnets can only be manufactured with features which allow for a single pressing axis.
5. It may not be feasible to produce injection moulded components with thin walls or small features.

The main benefit of bonded parts is the flexibility to be able to manufature to complex shapes and forms while still having a magnetic product. This can result in the shrinking of components or on the removal of other non-magnetic components from the application.

Magnetic & Physical Properties of Compression Bonded NdFeB

Magnetic Characteristics of Injection Moulded NdFeB

Magnetic Characteristics of Flexible/Rubber Magnets