Neodymium magnet, also known as NdFeB magnet, is a tetragonal crystal composed of neodymium, iron, and boron (Nd2Fe14B). In 1982, Sumitomo Special Metal's Sagawa Shinzo discovered neodymium magnets. The magnetic energy product (BHmax) of this type of magnet is greater than that of samarium cobalt magnets, making it the largest magnetic energy product in the world at that time. Later, Sumitomo Special Metals successfully developed the powder metallurgy process, while General Motors successfully developed the melt spraying process, which can prepare neodymium iron boron magnets. This type of magnet is a permanent magnet with magnetic properties second only to absolute zero degree holmium magnets, and is also the most commonly used rare earth magnet. Neodymium iron boron magnets are widely used in electronic products, such as hard drives, mobile phones, headphones, and battery powered tools.

To avoid corrosion damage, it is necessary to perform protective treatment on the surface of permanent magnet materials during use, such as electroplating with gold, nickel, zinc, tin, and spraying epoxy resin on the surface.