METHOD FOR IMPROVING MAGNETIC PERFORMANCE OF SINTERED NEODYMIUM-IRON-BORON PERMANENT MAGNET

摘要

Provided is a method for improving the magnetic performance of a sintered neodymium-iron-boron permanent magnet. According to the method, a sintered magnet undergoes inductive eddy current heating to turn a neodymium-rich phase thereof into a liquid phase, thus on the one hand, under the effect of an induced electromagnetic field, the flow of the neodymium-rich liquid phase can be intensified through electromagnetic stirring of induced eddy currents, so as to optimize the microstructure of the magnet; and on the other hand, main phase grains are more prone to rotate along the magnetic field direction of an induction coil, further increasing the degree of orientation of the magnet. Experiments prove that the coercive force of the sintered neodymium-iron-boron permanent magnet is somewhat improved, so does the squareness thereof. And meanwhile, both the remanence and the maximum magnetic energy product of the permanent magnet are also boosted. In addition, the method has the advantages of cleanliness without any pollution, high energy efficiency, great simplicity and practicability and so forth, and accordingly is highly promising in application.