Neodymium magnets (Nd-Fe-B) are composed of Neodymium, Iron, Boron and a few transition metals. They offer the highest energy product of any material today and are available in a very wide range of shapes, sizes and grades. Since commercially available at 1984, they are widely applied in more and more fields, include high performance motors, brushless DC motors, magnetic separation, magnetic resonance imaging, sensors and loudspeakers, etc.
Machining and tolerances
Neodymium (we like to just call it Neo) is easily ground, although coolants must be used in the process to avoid spontaneous combustion of powder. Grinding should be completed before coating or plating is applied to protect the magnets from corrosion. Standard tolerances for neodymium magnets are +/-.005 for ground dimensions.
Neodymium magnets require extremely high magnetizing fields and particular consideration must be given to this when designing complex assemblies. Neodymium can be magnetized in any direction as long as it is aligned properly. In some instances multiple pole magnetization is not possible; when it is possible, special fixtures are required.
Generally, surface treatment is very important for Neodymium magnets, almost all kinds of surface coating could be successfully applied to Neodymium magnets, like NiCuNi, Zn, Epoxy, Chromium, etc.