Surface Treatment of Magnet
The most common coating for Neodymium magnets is Nickel + Copper + Nickel (Ni + Cu + Ni). This coating offers the magnet relatively good protection from corrosion and passive applications. If the magnet will be exposed to moisture or liquid then consider the use of an organic coating such as Epoxy. A hard wearing coating, Epoxy is suited to applications where the magnet will come under some friction or knocking.
Neodymium Magnet Coating & Plating
Plating / Coating Options
The following is a list and description of available coating options for custom magnets. Note: Magnets can only be electro-plated before magnetization. if the plating is compromised after magnetization via abrasion or deliberate machining they cannot be re-plated. Some coatings such as plastic may be done after magnetization, If the process does not exceed the magnets maximum operating temperature.
| Plating \ Coating | Appearance | Indoor Use | Abrasion (Wear) | Humidity | Water | Salty Air (Near Ocean) | Salt Water | Thickness | Price |
| Nickel (Ni-Cu-Ni) A very durable multilayer combination of nickel, copper, nickel. The most common plating. |  | Excellent | Good | Good | Bad | Bad | Bad | 10-20 Microns | Low |
| Zinc Plating (Zn) 2nd most common plating, Zinc is a standalone plating with only one layer. It is a self- sacrificing coating, meaning when the material corrodes the outside turns white creating a durable layer of protection. |  | Excellent | Excellent | Excellent | Good | Good | Bad | 8-10 Microns | Low |
| Epoxy (Ni-Cu-Be) Epoxy plating is multilayered in Nickel, Copper, Epoxy. Great for outdoor applications. However it is not very abrasion resistant and prone to scratching. |  | Superior | Bad | Superior | Superior | Excellent | Excellent | 15-25 Microns | Medium |
| Gold (Ni-Cu-Au) Well known for its corrosion resistance. Layered in Nickel, Copper & Gold on top. Works very well in water applications. |  | Superior | Good | Superior | Superior | Superior | Superior | 10-20 Microns | High |
| Plastic Plastic is the most corrosion resistant. However its is thicker than other platings. A mold is required to create the plastic shell. |  | Superior | Superior | Superior | Superior | Superior | Superior | 250-500 Microns | Medium |
| Phosphate Phosphate is a temporary coating that will last only a few months. It is normally used when the magnet is going to be over-molded or encased in a plastic part that will act as the final protective layer. |  | Good (Temp) | Bad | Bad | Bad | Bad | Bad | 1-2 Microns | Low |
