General Information  

Collectively known as Rare Earth magnets, Neodymium Iron Boron (NdFeB) magnets are alloys of the Lanthanide group of elements. Rare Earth magnets are the most advanced commercialized permanent magnet materials today.

NdFeB magnets are available in a number of different grades that span a wide range of properties and application  requirements.NdFeB magnets are available in sintered forms. The sintered form usually requires some finishing operations in order to hold close mechanical tolerances.

NdFeB magnets are brittle (though not as brittle as theSmCo types), and machining operations should be performedprior to magnetization, using diamond tools. We are equipped to fabricate these materials to blueprint specifications.  

All sintered NdFeB magnets,  are anisotropic, and can only be magnetized in the orientation direction.  although special magnetizing fixtures are required for this. In general,magnetizing fields of about 30 KOe are required to saturate NdFeB magnets.  

Assemblies  

We are able to manufacture metal and other components of finished sub assemblies using our CNC machining facilities.

Assemblies can be fabricated by adhering magnets with adhesives to suit a range of environments, by mechanically fastening magnets, or by a combination of these methods. Due to the relatively brittle nature of these magnet materials, press fits are not recommended.

When multiple magnets are assembled in repelling positions, it is advisable to use mechanical fastening in addition to adhesives, since if adhesives were to give way, repelling  magnets may dislodge and endanger personnel using them.

Our design engineering team will be happy to assist you in designing housings for your magnet assemblies.  

Surface Treatments  

The corrosion resistance  of NdFeB is considered poor. Painting, coating, or plating is therefore highly recommended for NdFeB. Plating NdFeB is a difficult process, and commercial plating houses are unlikely to be able to achieve plating with good adhesion. Nickel, Zinc, or Tin plating provides good corrosion resistance for NdFeB magnets. We are also able to cadmium chromate or aluminum chromate plate NdFeB using vacuum deposition techniques. A variety of organic coatings have also been successfully developed for NdFeB, exhibiting good corrosion resistance characteristics. For especially harsh environments, it may be advisable to use a combination of coating techniques, or to encapsulate the material in a sealed housing.  

Magnetizing and Handling

All Rare Earth magnets require extremely high magnetizing fields and special consideration must be given to this when designing complex assemblies, if it is intended to magnetize after assembly. Consult us if you foresee any problems.

Rare Earth materials are mechanically weak, and magnetically very strong. They must therefore be handled very carefully to avoid damage and injury to personnel handling the magnets. Receiving and assembly personnel should be warned about the of handling magnetized Rare Earth magnets.

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