Magnet coating treatment is mainly aimed at the special working environment of magnets. For example, the working environment of motor magnets and iron separator magnets is relatively humid, so surface coating treatment is required. At present, the main coating technologies for magnets include: zinc plating, color zinc plating, nickel plating, black nickel plating, nickel copper nickel plating, gold plating, silver plating, and epoxy resin plating.
The surface coating treatment of neodymium iron boron magnets can be processed by different electroplating processes according to the use characteristics of the product and the storage time. The most common electroplating process is zinc plating and nickel plating. The surface color of each plating layer is different. Each has its own advantages and disadvantages.
Galvanized: The surface looks silvery white. It can be used for 12-48 hours of salt spray. It can be used for bonding with some glues (such as AB glue). If electroplated, it can be stored for two to five years. The advantage is that the price is relatively low. .
Black zinc plating: According to customer requirements, the surface of its products is treated to black. In terms of electroplating process, a black protective film is added through chemical treatment on the basis of galvanizing. This film can also protect the product. Increase the salt spray time and prolong the oxidation time. However, the surface is easily scratched and loses its protective effect.
Nickel plating: looks like stainless steel gloss, the surface is difficult to be oxidized in the air, and the appearance is good, the gloss is good, the electroplating can pass the salt spray test for 12-72 hours. The disadvantage is that it cannot be used for bonding with some glues, which will cause the coating to fall off and accelerate oxidation. Nowadays, most of the market is nickel-copper-nickel. This electroplating method is used for 120-200 hours of salt spray, but the electroplating cost is relatively high .
Gold-plated and silver-plated: mostly used for magnetic jewelry, magnetic jewelry is golden yellow, mostly silver-white. The appearance of gold-plated magnets looks very beautiful like gold. They are generally used in the jewelry industry. Our products can also be gold-plated for magnetic jewelry.
Epoxy resin plating: the magnet is coated with a layer of resin paint after nickel plating. The biggest advantage is that it can extend the salt spray test time.
Chrome plating: Chrome plating is generally rare, because its chrome plating process has strong corrosion resistance and is difficult to react with other substances. It is generally used in the harsher working environment with strong pH. The cost of electroplating is very high, and most companies cannot accept it, so few people choose it.
