The sintered NdFeB strong magnetic coatings are nickel, copper, chromium, gold, zinc, black zinc, and epoxy resin. Its surface plating is different, its color is also different, and its storage time is also different. Each has its own advantages and disadvantages.
1. Zinc: The surface looks silvery white, can be used for 12-48 hours of salt spray, and can be used for bonding with some glues (such as AB glue), such as sintered NdFeB strong magnetic plating, it can be stored for two to five years, the advantage is that the price is relatively low.
2. Nickel: It looks like a stainless steel color, it is difficult to be oxidized on the surface when left in the air, and the appearance is good, the gloss is good, and 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. To speed up the oxidation, most of the nickel-copper-nickel electroplating methods on the market do 120-200 hours of salt spray, but the electroplating cost is relatively high.
3. Copper: Mostly in the hardware industry, sintered NdFeB magnets are rarely used, and their appearance is yellow.
4. Chromium: The chromium electroplating industry is also relatively rare, and its electroplating cost is very high, which is unacceptable to general companies. However, its ability to put rot is very strong, and it is difficult to react with other substances. It is mainly used in places with strong pH, and the price of domestic products is relatively low, so few people choose it.
5. Black zinc: the surface of the product is treated to black according to customer requirements. In the 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, its surface is easily scratched and loses its protective effect. There are very few people who use it now, and most of them are replaced by resin. Below we explain.
6. Gold: This industry is very popular now, and most of the yellow gold ornaments in some stalls we see on the street are gold-plated or copper. The gold plating makes the product look as beautiful as gold, and is generally used in the jewelry industry. Our products can also be gold-plated for magnetic jewelry.
7. Epoxy resin: The effects of NI, ZN, epoxy resin, and parylene-C coating on the magnetic properties of NdFeB magnets in three solutions were compared and studied.
Polymer material>Epoxy resin>NI coating>ZN coating
It is to add a layer of resin paint on the outside of the product after nickel plating. This industry has only been in the market for the past two years, and its development speed is very fast. Now many people use it on various electroplating products. desired color.
Therefore, different colors are selected for the coating of sintered NdFeB magnets according to different needs.
