NdFeB magnets require a protective coating

Neodymium (Nd-Fe-B) magnets require a protective coating / surface finish to prevent corrosion of the magnet.

Moisture in the atmosphere is potentially enough to cause an uncoated NdFeB magnet to show signs of corrosion. The process of corrosion is similar to rusting ¨C the structure of the Neodymium magnets changes permanently resulting in a progressive loss in magnetic performance (the magnet will weaken; the magnet also breaks down into a powder during the corrosion process).

There is a variety of surface finishes available. The standard coating is a triple layer plating of Nickel-Copper-Nickel (Ni-Cu-Ni). Unless special requested otherwise, this Ni-Cu-Ni coating is always applied to the magnets.

The application sometimes affects the choice of coating. It should be noted that the level of protection given by any coating depends on the environment the neodymium magnet will be subjected to and how the coating is looked after. If the coating is scratched or broken, it will not offer protection from moisture.

Tags: neodymium magnets NdFeB magnets,protective,coating Smco magnets