At present,neodymium-iron-boron is the leading product of rare-earth permanent magnet materials
. However, according to the demand of current technology development, neodymium-iron-boron also has some limitations.In general, magnets are divided into two categories: sintered magnets and bonded magnets. Sintered Nd-Fe-B magnets are anisotropic and full-density magnets, which are widely used in many fields.The bonded Nd-Fe-B magnet is isotropic, and the deficiency of bonded NdFeB magnet is constantly highlighted. First of all, the magnetic particles are isotropic, and the maximum magnetic energy product can not exceed the 16MGOe.Secondly, the molding process also has some limitations: Nd-Fe-B rapidly quenched magnetic powder is mainly used to make compressed bonded magnets, and its output only accounts for 3% of the total bonded magnets.With the development trend of miniaturization of electrical appliances, the development of bonded magnets with high magnetic energy product has become a new demand direction in the permanent magnet market.