What Are The Common Coatings For Sintered NdFeB Magnets

What are the common coatings for sintered NdFeB magnets? The coatings of sintered NdFeB magnets are nickel, copper, chromium, gold, zinc, black zinc, 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. It can be used as salt spray for 12-48 hours. It can be used for bonding with some glues. , the advantage is that the price is relatively low.

2. Nickel: It looks like the color of stainless steel, 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: It mostly appears in the hardware industry, and 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 generally unacceptable to 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.

5. Black zinc: according to customer requirements, the surface of the product is treated into black. In the electroplating process, a black protective film is added through chemical treatment on the basis of galvanizing. This film can also play a role in protecting 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. Most of the yellow gold ornaments in some stalls we see on the street are gold-plated or copper. 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 comparatively studied. Polymer material>epoxy resin>NI coating>ZN coating 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 in the past two years, and its development speed is very fast. Now various electroplating products There are many people who use it, and its big advantage is that it can do the color you want.

Therefore, different colors are selected for the coating of sintered NdFeB magnets according to different needs.