Sintering method of neodymium-iron-boron magnet

Abstract

The invention provides a sintering method of a neodymium-iron-boron magnet. A plurality of steps in a preparation process of the neodymium-iron-boron magnet are analyzed; grain growth can be significantly prevented by use of a segmented sintering method from a neodymium-iron-boron sintering process; and the magnet with fine grains and uniform density is obtained, so that the magnetic property of the magnet is significantly improved; especially for the neodymium-iron-boron magnet with low rare earth content, the problems that grains abnormally grow and the residual magnetism and the square degree of the magnet cannot reach the requirements due to the fact that the granularity of neodymium-iron-boron magnet powder and the oxygen content in the process are reduced are solved when heavy rare earth content is reduced within the industry. By the method provided by the invention, the neodymium-iron-boron magnet which is free of abnormal grain growth and has better residual magnetism and square degree can be obtained.

Description

technical field [0001] The invention belongs to the technical field of magnet preparation, and in particular relates to a sintering method of an NdFeB magnet. Background technique [0002] Hard magnets are permanent magnets, magnets that can maintain their magnetism for a long time, and are not easy to lose their magnetization or be magnetized. Therefore, whether in industrial production or in daily life, hard magnets are one of the most commonly used strong materials. Hard magnets can be divided into natural magnets and artificial magnets. Artificial magnets mean that by synthesizing alloys of different materials, the same effect as natural magnets (magnets) can be achieved, and the magnetic force can also be improved. In the 1960s, the emergence of rare earth permanent magnets opened up a new era for the application of magnets. The first generation of samarium cobalt permanent magnets SmCo 5 , the second generation of precipitation hardening samarium cobalt permanent mag...

AI Technical Summary

Problems solved by technology

Adding rare earth elements to magnets is a major means of improving magnetic properties, but as the price of heavy rare earths continues to rise, the industry needs to consider cost factors and reduce the use of heavy rare earths while pursuing high performance. For sintered neodymium For iron-boron magnets, the use of heavy rare earths is reduced, which usually causes abnormal growth of grains, which in turn affects magnetic properties

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