Coating & Platings
Plating neodymium magnets is an important process to protect the magnet against corrosion. The substrate NdFeB(Neodymium, Iron, Boron) will oxidize quickly without a protective layer. Below is a list of platings and their effectiveness in certian environments.
Plating / Coating | Indoor Use | Abrasion Resistance | Humidity | Water | Salty Air | Salt Water | Glue | Thickness | Price | ||
Nickel (Ni-Cu-Ni) |
Excellent | Good | Good | Bad | Bad | Bad | Bad | 10-20 Microns | Low | ||
Zinc (Zn) |
Excellent | Excellent | Excellent | Good | Good | Bad | Good | 8-10 Microns | Low | ||
Gold (Ni-Cu-Au) |
Excellent | Good | Good | Bad | Bad | Bad | Bad | 10-20 Microns | High | ||
Black Epoxy (Ni-Cu-BE) |
Superior | Bad | Superior | Superior | Excellent | Excellent | Good | 15-25 Microns | Medium | ||
Raw Epoxy (BE) |
Superior | Good | Superior | Superior | Excellent | Excellent | Superior | 10-20 Microns | Medium | ||
Plastic (ABS) |
Superior | Superior | Superior | Superior | Superior | Superior | Excellent | >800 Microns | High | ||
Teflon (PTFE) |
Superior | Superior | Superior | Superior | Superior | Superior | Bad | 250-500 Microns | High | ||
Everlube-6155 |
Superior | Superior | Superior | Superior | Superior | Superior | Good | 8-25 Microns | High | ||
Xylan |
Superior | Superior | Superior | Superior | Superior | Superior | Good | 15-30 Microns | High | ||
Parylene |
Superior | Superior | Superior | Superior | Superior | Superior | Good | 15-30 Microns | High |
*** Superior > Excellent > Good > Bad
*** Note: All coatings / platings must be done at the factory before the magnet is saturated(charged). The magnetic field will disrupt the electroplating process, while the heat required for other types of platings would demagnetize the magnet.
Surface Coating of Sintered Neodymium Magnet
Nickel (Ni-Cu-Ni)
The most common plating. Ni-Cu-Ni is a durable 3 layer (nickel, copper, nickel coating). Great for indoor use. They may be used outdoors if protected from rain and humidity. Good abrasion resistance.
Zinc (Zn)
Zinc is a standalone (one layer) plating. Zinc is self- sacrificing, meaning when it starts to oxidize the outside turns white creating a durable layer of protection.
Black Epoxy (Ni-Cu-BE)
Black Epoxy plating is consists of 3 layers Nickel, Copper, and Epoxy exposed as the top layer. Great for outdoor applications. However, black epoxy is not as abrasion resistant as other platings. In harsh conditions the epoxy layer may be scrached off to expose the copper layer underneath.
Gold (Ni-Cu-Ni-Au)
A very thin / cosmetic layer of gold. Usually produced with an underlying layer of nickel to create a brighter finish.
Color Zinc
Permanent Nd Magnet with Color Zinc coating application, it has excellent salt spray resistance.
Raw Epoxy (BE)
Raw Epoxy is designed specifically for gluing applications where the magnet requires a good adhesion to epoxy glue. This coating consists of one layer of epoxy covering the magnet.
Black Nickel
Permanent Neodymium Magnet with Black Nickel coating application, it has regular protection but low cost.
Phosphated Coating
Permanent Sintered NdFeB Magnet with Phosphated or Passivation coating application, the coating is only for Temporary Protection.
Silver (Ni-Cu-Ni-Ag)
Permanent Sintered NdFeB Magnet with Silver (Ag) coating is a very thin / cosmetic layer. Usually produced with an underlying layer of nickel to create a brighter finish.
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Passivation Plating
Permanent Neo Magnet with Phosphated or Passivation coating application, the coating is only for Temporary Protection.
Everlube Plating
Everlube 6155 is a aluminized barrier coating specially formulated to maximize adhesion and corrosion protection when applied to rare earth magnets. The coating is very durable and provides excellent chemical and corrosion resistance.
Teflon (PTFE)
Teflon is very resilient and can withstand harsh environments. It is highly corrosion resistant. An injection mold is required to create the shell around the magnet. There will be a noticeable mold seam around the magnet where the injection mold separates.
Plastic (ABS)
ABS Plastic is highly corrosion resistant. This coating requires an injection mold to be created in order to encase the magnet. The plastic shell needs to be thicker than other coatings so the plastic can flow during the injection process. Multiple colors available.
Ion Vapor Deposition (IVD) Aluminum Coating
For NdFeB magnet, its aluminum plating process contains ion vapor deposition technology and ion liquid electrodeposit. In fact, the application of ion liquid electrodeposit in NdFeB industry is not yet implemented, and all of the aluminum coating magnet are manufactured by ion vapor deposition technology.
Surface Coating of Bonded Neodymium Magnet
JOFOV can provide epoxy resin electrophoresis, acrylic resin electrophoresis, epoxy resin spraying, Teflon spray, Parry deposition, vacuum soaking and other coating and surface treatment technology to meet the requirements of corrosion resistance, solvent resistance and friction resistance in the long-term and different use environment. Specific coating requirements can be selected and stacked according to the environmental requirements.