neodymium iron boron magnets are generally nickel-plated, copper, chromium, gold, black zinc, blue and white zinc, epoxy resin. Plating the different, the color of the surface of the magnet will be different, long-term preservation of the length of time.
The effect of NI, ZN, epoxy resin and PARYLENE-C coating on the magnetic properties of NdFeB magnets in three solutions was studied by comparing the effects of NI, ZN and epoxy resin.
Polymer Materials> Epoxy Resin> NI Coating> ZN Coating
The results show that the protective effect of the polymer coating on the magnet is the best in the environment of acid, alkali and salt. The epoxy resin is relatively poor. The NI coating is the second, and the ZN coating is relatively poor.
Salt spray test machine
Zinc: the surface looks silver and white, can do 12-48 hours salt spray, can be used in some glue bonding, (such as AB glue), such as plating can be stored for two years to five years.
"How about a gold-plated jade?"
Galvanized NdFeB counterbore magnets
Nickel: seemingly stainless steel color, stay in the air surface is difficult to be oxidized, and the appearance of good, good gloss, plating can be 12 - 72 hours salt spray test. Its shortcomings can not be used and some glue to do the bonding, this will make the coating off.
Advantages: look good
Disadvantages: easy to fall off the coating
Copper: more in the hardware industry, NdFeB industry rarely used, its appearance was yellow.
The appearance is yellow
Chromium: chromium plating industry is also relatively rare, the high cost of plating, the general company can not accept. But its rotative ability is very strong, it is difficult to react with other substances. Mainly used in places where the pH is strong. Generally rarely choose this.
Black zinc: according to customer requirements will be its product surface treatment into black, in the plating process is mainly based on the galvanized by chemical treatment plus a layer of black protective film, the film can also play a protective product use, growth Salt spray time, extended by oxidation time. But its surface that is easy to be scratched, lost its protective effect. Now people use very little, mostly replaced by resin.
Mostly replaced by resin
Gold: we took to the streets to see some of the stalls of the yellow gold jewelry mostly gold-plated, or copper. Gilded to make the product looks like gold is very beautiful, generally used for jewelry industry, our products can also be gold, for magnetic jewelry.
Can do magnetic jewelry
Epoxy resin: nickel plating in the product and then add a layer of resin paint outside, the industry in the past two years only the market, its development is very fast, and now a variety of electroplating products with a lot of people, its biggest advantage is Can do the color you want.
Advantages: all kinds of colors can be
PS: should be based on the use of the environment to choose the appropriate coating. Do not have the manufacturer's coating is not the same, the most important reason is the length of the chamfer and plating time, do not understand the case of magnet plating, we should determine how good the quality of the coating, in fact, there is a simple and quick way is Look at the coating, the more bright the better the quality of the coating, so when you choose to order the magnet, try to choose the industry more well-known enterprises to ensure the quality of the coating.