NdFeB, also known as NdFeB magnet, is a tetragonal crystal formed of neodymium, iron, and boron (Nd2Fe14B).

A neodymium magnet was discovered in 1982 by Masato Sagawa of Sumitomo Special Metals, Japan. The magnetic energy product (BHmax) of this magnet was larger than that of the samarium cobalt magnet, and it was the substance with the largest magnetic energy product at that time in the world. Later, Sumitomo Special Metals developed the powder metallurgy process.


General Motors has successfully developed a melt-spinning process that can produce neodymium-iron-boron magnets. This kind of magnet is the strongest permanent magnet and the rare earth magnet most commonly used today. NdFeB magnets are called "Magnetic Kings" because of their excellent magnetic properties. Because the surface is easily corroded by oxidation, NdFeB must be surface-coated. Surface chemical passivation is one of the good solutions.


Sintered NdFeB permanent magnet materials have excellent magnetic properties and are widely used in electronics, electric machinery, medical equipment, toys, packaging, hardware machinery, aerospace, and other fields. The more common ones are permanent magnet motors, speakers, magnetic separators, Computer disk drives, magnetic resonance imaging equipment, etc.

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