In the early 80s of last century, people have developed the third generations of rare earth permanent magnets successfully——NdFeB. Since the appearance of NdFeB, it has rapidly entered industrial production due to its excellent magnetic property and wonderful cost performance. Nd2Fe14B, as an important functional material, has been widely applied to stepper motors and spindle motors. It has played a significant role in many fields such as computers, office automation products and automobile industry.
But the corrosion resistance of all kinds of magnets are poor. The chemical activity of iron in the magnet is strong and easy to be oxidized. Then on the surface of the magnet the microbatteries are are easy to form in a wet environment, which increase the rate of corrosion. The corrosion causes deformation and powder in different degrees. This will lead to a decrease in magnetic properties which affects the normal operation of the device. Therefore, finding the solution of corrosion resistance of neodymium magnets is one of the key problems that affect its application. At present, the way of coating the surface is usually used to improve its corrosion resistance property.
The way of plastic coating
is a widely used for Nd2Fe14B industry with good corrosion resistance property, especially for smaller sheet, tile and tubular NdFeB parts. Not only is the actual operation very convenient, but also the production efficiency is very high. In the actual production, the plastic coating method has been widely applied, because it can solve some problems that caused by other coating methods.