Which magnet coatings are there?

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Neodymium magnets (super magnets): Coating necessary

Nickel (Ni-Cu-Ni)

Gold-coating (Ni-Cu-Ni-Au)

Chrome (Ni-Cu-Ni-Cr)

Copper (Ni-Cu)

Epoxy resin (Ni-Cu-Ni-Epoxy)

Zinc (Zn)

Pot magnets

Special coatings

Ferrite magnets: No coating

Neodymium magnets (super magnets): Coating necessary

Neodymium reacts to oxygen and oxidises quickly if untreated. That's why all neodymium magnets in our shop are covered with a protective coating, which is so thin that it doesn't have any impact on the adhesive force of the magnet.

We use the following coatings on our neodymium magnets:

Nickel (Ni-Cu-Ni)

By far the most frequently used coating

Colour: shiny metallic

Good price/performance ratio

Thickness: approx. 12 micro metres

Gold-coating (Ni-Cu-Ni-Au)

Razor-thin coating (24k) over normal Ni-Cu-Ni coat, but with the same features

Colour: shiny metallic

Thickness of gold-coating without Ni-Cu-Ni: 0,05 micro metre

Thickness of whole coating: approx. 12 micro metres

The gold-coating rubs off easily with frequent use. It is therefore suitable for decorative purposes only, not for playing or working.

Chrome (Ni-Cu-Ni-Cr)

Better resistance against rubbing and pressure (that's why we use this coating for our sphere magnets)

Colour: dull, grey-metallic

Thickness: approx. 15 micro metres

Copper (Ni-Cu)

Colour: shiny brown-red-gold. The colour may change over time due to oxidation (darkening, spots)!

Slightly weaker rubbing and impact resistance than Ni-Cu-Ni

Slightly weaker corrosion resistance than als Ni-Cu-Ni

Thickness: approx. 10 micro metres

The copper-coloured surface rubs off with frequent use (similar to gold-coated magnets) and is therefore suitable for decorative purposes only.

Epoxy resin (Ni-Cu-Ni-Epoxy)

(in exceptional cases also just epoxy)

Colour: black

almost 100% non-corrosive, as long as coating is intact

not shock-resistant (crumbles quickly)

Thickness: approx. 10 micrometre

Even the smallest, not visible to the eye, damages of the coating will cause damage to the magnet in the long term when exposed to moisture.

Zinc (Zn)

Colour: matt grey/blueish

only zinc without Ni-Cu-Ni

more susceptible to corrosion than Ni-Cu-Ni

can leave black marks

Thickness: approx. 4 micrometres

Pot magnets

If not noted otherwise, we use neodymium magnets with a Ni-Cu-Ni coating for our pot magnets. The term "coating" in the article description of pot magnets refers to the steel pot around the magnet. In most cases it is nickel (Ni); for the pot magnets that are painted white it is nickel with additional powder coating.

Special coatings

There is a variety of other coatings for neodymium magnets that we do not (or only sporadically) offer in our standard assortment.

Without coating

Naked magnet material, black/grey

Magnets oxidise and corrode quickly when they come in contact with oxygen and water

Magnets need to be covered air- and watertight quickly

We do not recommend having uncoated magnets manufactured.

Silver (Ni-Cu-Ni-Ag)

Shiny silver

Razor-thin coating over normal Ni-Cu-Ni coating, hence the same attributes

Difference purely visual

Material: Sterling Silver

Approx. 12 micrometres thick

Teflon

Grey/anthracite

Only teflon without Ni-Cu-Ni

Nearly waterproof

Very rub-resistant

12-25 micrometres thick

Ferrite magnets: No coating

In theory, you could put various coats on ferrite magnets, but that is technically complex and expensive. The price for the coating would be greater than the price for the whole magnet.

Since ferrite magnets are weather-resistant even without protection, an additional coating is not necessary. Our ferrite magnets are therefore uncoated.

HIGH-END PERMANENT DESIGN EXPERT,YOUR SOLUTION CONSULTANT.

Which magnet coatings are there?

Which magnet coatings are there?