High-performance rare earth permanent magnet sintered magnet and manufacturing method thereof

Abstract

The invention provides a rare earth sintered magnet and a manufacturing method thereof. The magnetic property residual magnetism Br of the magnet is between 12.8 and 13.3 kGs, the intrinsic coercivity Hcj is more than or equal to 30 kOe, and the content of oxygen in the magnet is between 500 and 900 ppm. The rare earth sintered magnet is prepared by the manufacturing process that: a smelting procedure is a vacuum quick-setting process, and the thickness of produced sheet alloys is between 0.1 and 0.5mm; a hydrogen decrepitation process is used for production in an intermediate crushing procedure; a jet mill is used for production in a micro powder manufacturing procedure, and the average particle size of micro powder is between 3.0 and 4.5 mu m; a compression procedure is used for compression molding under the environment of anaerobic inert gas; and a sintering procedure is used for sintering and aging by means of a vacuum sintering furnace.

Description

technical field [0001] The invention relates to a high-performance rare-earth permanent magnet sintered magnet and its manufacturing method, especially a double-high rare-earth permanent magnet sintered magnet with a remanence of 12.8-13.3kGs and an intrinsic coercive force not less than 30kOe and its production method. Background technique [0002] In recent years, NdFeB magnets have been used more and more in industries such as electronic information, IT, automobiles and machinery manufacturing, and have also achieved rapid development along with the development of these industries. Correspondingly, the increase in the functions of electronic information, IT, automobile and machinery manufacturing products and the improvement of technology in the application of magnetic devices have put forward higher requirements for the performance of magnetic materials. Magnetic materials must meet the requirements of miniaturization, patching, high magnetic performance, low loss requir...

AI Technical Summary

Problems solved by technology

[0007] For the first method, it is difficult to control the diffusion rate of heavy rare earth elements when this method is actually implemented, so the heavy rare earth elements will also diffuse to the center of the crystal grains, so that the coercive force of the magnet is increased and the remanence is greatly reduced.

The performance uniformity of the produced magnets is very poor, and it is impossible to achieve stable and accurate control of the magnet performance

[0008] For the second method, the diffusion depth of heavy rare earth elements has a great influence on the Hcj of the magnet. Due to the uneven diffusion depth of heavy rare earth elements relative to the surface depth of the magnet in the diffusion reaction, the consistency of the magnets produced in large quantities cannot be guaranteed, resulting in difficulties for customers to use.

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