Surface coating method for improving coercive force of rare earth permanent magnet

Abstract

The invention discloses a surface coating method for improving the coercive force of a rare earth permanent magnet. The method comprises the following steps of: A, spraying a rare earth mixed solutionon the surface of a permanent magnet by adopting a laser coating machine, and B, performing heat treatment on the sprayed permanent magnet. The rare earth mixed solution in the step A is composed ofneodymium, promethium, samarium, europium, holmium, ytterbium, tetrabutyl titanate, acid compound phosphate and water, and the weight parts are: 3-6 parts of neodymium, 2-6 parts of promethium, 2-5 parts of samarium, 3-8 parts of europium and 4-10 parts of holmium. On the premise of not introducing excessive impurity additives and not affecting the structure (corrosion, oxidation and the like) ofthe permanent magnet, the coercive force of the permanent magnet can be greatly improved by using less rare earth (the coercive force of the permanent magnet is improved by more than 5000 A/m on the original basis), the production cost of the permanent magnet is effectively reduced, the residual magnetism and the magnetic energy product are not influenced, the coercive force is greatly improved, meanwhile, the operation process is simple, and the method is suitable for large-scale industrial application.

Description

technical field [0001] The invention relates to the technical field of permanent magnets, in particular to a surface coating method for raising coercive force of rare earth permanent magnets. Background technique [0002] Magnets that can maintain their magnetism for a long time are called permanent magnets, such as natural magnetite (magnetite) and artificial magnets (alnico) The demand for hybrid electric vehicles, pure electric vehicles and energy-saving air-conditioning compressors is increasing, and the demand for rare earth permanent magnet materials with high coercive force (such as R-Fe-B series rare earth permanent magnets) is also increasing , the traditional method of improving the coercive force requires the use of a large amount of rare earth elements, resulting in a substantial increase in the cost of the magnet, and will sacrifice part of the remanence and energy product. Therefore, we propose a surface coating method for rare earth permanent magnets to increa...

AI Technical Summary

Problems solved by technology

[0002] Magnets that can maintain their magnetism for a long time are called permanent magnets, such as natural magnetite (magnetite) and artificial magnets (alnico) The demand for hybrid electric vehicles, pure electric vehicles and energy-saving air-conditioning compressors is increasing, and the demand for rare earth permanent magnet materials with high coercive force (such as R-Fe-B series r