Anisotropic magnetic powder and manufacturing method thereof

Abstract

The invention provides a high-performance bonded rare earth permanent magnet powder and a preparation method thereof. Raw material compositions and the preparation method of the rare earth permanent magnet powder are as follows: an alloyed casting strip, the composition ratio of which is R1-xNdx8 to 20MyFebalB4 to 12(atm%), is prepared to be high-performance bonded anisotropic magnet powder through a heat treatment (or untreated process), a hydrogenation and dehydrogenation process and fragmentation. The preparation method comprises the following steps: a rare-iron-boron alloyed casting strip is prepared through a strip casting process, the thickness of the rare-iron-boron alloyed casting strip is 0.1 mm to 1.0 mm; and finally the bonding rare earth permanent magnet powder with high coercive force and high oxidation resistance are prepared through the processes of hydrogenation and dehydrogenation. Compared with the magnet powder taking the traditional cast ingot as the raw material, the bonded magnet powder has higher magnetism property and higher oxidation resistance property.

Description

technical field [0001] The invention relates to a manufacturing method of rare earth-iron-boron alloy and anisotropic bonded magnetic powder. Background technique [0002] Bonded NdFeB magnets have excellent magnetic properties, mechanical properties, good processability, have good application prospects and development prospects, and are widely used in automobiles, computer peripherals, electronics, office automation and other electronic devices. Among them, 80% bonded NdFeB magnets are used in the spindle motors and stepping motors of HDD, CD2ROM, DVD2ROM, and there is still great potential in the market demand in fields such as automobiles and small tools. However, in order to adapt to the further miniaturization of components and systems, save power consumption, and reduce manufacturing costs, it is required to further improve the magnetic properties of bonded rare earth magnets, and the most effective way to improve magnetic properties is to prepare anisotropic bonded ma...

AI Technical Summary

Problems solved by technology

[0005] 2) The distribution of neodymium-rich phase in the alloy is extremely uneven;

[0006] 3) The solidification rate of the alloy is low, and it is difficult to reduce the rare earth content in the alloy;

[0007] 4) Conventional heat treatment is difficult to completely solve the above problems

[0009] Patent CN02805171.8 uses the method of forming a solidified alloy layer to prepare a master alloy, but there is still an α-Fe phase, and it is difficult to obtain a high-performance bonded magnet

Images