By their nature, Neodymium magnets are a brittle material that require coatings to help protect against breakage, scratches or corrosion. That’s why, at FIRST4MAGNETS® we supply all our Neodymium magnets already triple-coated (unless specifically requested otherwise). The typical coating for a Neodymium magnet is a layer of nickel followed by a layer of copper and then nickel again. However, there are many different coatings used on our magnets including gold, rubber, Polytetrafluoroethylene (PTFE) and more. These coatings are all designed to fit a variety of applications and have a wide range of benefits to suit your requirements.
Good to know- During manufacture, all our magnets are thoroughly dried to prevent moisture being captured underneath the coating during the coating and plating process.
Good to know- A Neodymium magnet kept in dry conditions – not subjected to excessive heat, radiation or strong external magnetic fields will not corrode and will retain its magnetic output for many, many years. Permanent magnets lose their magnetism at a rate of approximately 5% every 100 years, meaning they aren’t actually ‘permanent’ in the truest sense of the word, but when handled with care, in the right conditions Neodymium magnets will maintain their magnetism for a very long time.
Ni-Cu-Ni |
Rubber |
Epoxy |
Au |
Zn |
PTFE |
Chrome |
|
Indoor Applications |
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Outdoor Applications |
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High Temperature Applications |
220-240ºC* |
80-100ºC or less |
150ºC or less |
Up to 200ºC |
120ºC or less |
Up to 250ºC |
Up to 200ºC |
Low Temperature Applications |
220-240ºC* |
80-100ºC or less |
150ºC or less |
Up to 200ºC |
120ºC or less |
Up to 250ºC |
Up to 200ºC |
Water Applications |
The below coatings are most commonly used with Neodymium magnets, designed with specific applications in mind.
Tin (Sn)
Tin plating/coating creates resistance against corrosion, ductility, and solderability. Due to its low transfer resistance means they are commonly used in electrics and electronic industries.
Titanium (Ti)
This is a coating that when applied creates resistance to corrosion in sea water, aqua regia, and chlorine.
Titanium Nitride (TiN)
This is a coating that when applied creates resistance against most chemicals. This coating is commonly used for medicine applications due to its high corrosion resistance and being non-reactive within human bodies. Maximum working temperature is approximately 500 ° C.
Parylene C
This coating provides protection from moisture, corrosive bodily fluids, chemicals, temperature and fungus. As such, they are most commonly used within medical and technology applications. Parylene coated magnets can also be suitable for outdoor applications, where the maximum working temperature is approximately 150°C.
Everlube®
Everlube® created a range of tough coatings, to suit a variety of needs. Magnets can be coated in this to help protect against chemical corrosion, high temperatures and rust.
Nickel-Copper-Nickel – Plus Rubber
These coatings have the same advantages of Nickel-Copper-Nickel coating, such as protection against corrosion, but with rubber added it also creates good slip resistance. Ideal for using on applications steel surfaces.
Zinc – Plus Rubber
This coating benefits from working in low temperatures thanks to the zinc element, and when partnered with rubber, allows for the magnet to be slip resistant. Ideal for using on applications on steel surfaces or within water or low temperature applications.
Nickel-Copper-Nickel – Plus Parylene
These coatings boast the same advantages of Nickel-Copper-Nickel coating, but by adding Parylene, this supports the magnet further for electrical applications.
Nickel-Copper-Nickel – Plus PTFE
These coatings boast the same advantages of Nickel-Copper-Nickel coating, but by adding PTFE creates an added protective coating against impacts and breakages.
Tin – Plus Parylene
Both Tin and Parylene can be used within electric circuits and electrical insulation. When they are combined together, they create the perfect combination whilst aligning both of their benefits together.
Phosphate passivation
Phosphate coating provides strong adhesion and corrosion protection and also improves the friction properties of sliding components.
For help and advice on choosing the right coating for your application call our technical experts today on
0845 519 4701 | sales@first4magnets.com