Unlock instant, AI-driven research and patent intelligence for your innovation.

Preparation method of neodymium-iron-boron magnet

A technology of NdFeB and magnets, which is applied in the direction of magnetic objects, inductors/transformers/magnets manufacturing, magnetic materials, etc., can solve the problem of low utilization rate of heavy rare earths, difficulty in further improving magnetic properties such as coercive force of iron-boron magnets, heavy rare earths Diffusion depth is shallow and other problems, to achieve the effect of improving utilization rate, increasing coercive force, and increasing diffusion depth

Pending Publication Date: 2022-03-11
NINGBO INST OF MATERIALS TECH & ENG CHINESE ACADEMY OF SCI
View PDF0 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0003] The grain boundary diffusion method can improve the coercive force of NdFeB magnets. The traditional grain boundary diffusion method usually sets a heavy rare earth film on the surface of the NdFeB prefabricated magnet, and then performs diffusion treatment and tempering treatment. However, the traditional grain boundary diffusion method , the diffusion depth of heavy rare earths is shallow, which leads to a decrease in the utilization rate of heavy rare earths. At the same time, heavy rare earths are easy to diffuse from the grain boundary phase to the main phase, resulting in the formation of an abnormal core-shell structure. difficult to improve

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Examples

Experimental program
Comparison scheme
Effect test

preparation example Construction

[0021] The preparation method of the neodymium-iron-boron magnet provided by the invention comprises the following steps:

[0022] S1, providing NdFeB prefabricated magnets;

[0023] S2, forming an aluminum-doped heavy rare earth film on the surface of the NdFeB prefabricated magnet to obtain a NdFeB magnet blank, wherein the material of the aluminum-doped heavy rare earth film includes elemental aluminum and heavy rare earth; and

[0024] S3, performing diffusion treatment and tempering treatment on the NdFeB magnet blank to obtain the NdFeB magnet.

[0025] In step S1, in order to enable the aluminum-doped heavy rare earth film to be better bonded to the NdFeB prefabricated magnet, in one embodiment, it also includes performing pretreatment on the provided NdFeB prefabricated magnet, and the pretreatment includes alkali cleaning Degreasing, pickling and rust removal, water washing, alcohol washing and drying.

[0026] Specifically, the step of alkaline cleaning and degreas...

Embodiment 1

[0051] The NdFeB prefabricated magnets with a size of Φ10mm×5mm are subjected to alkaline cleaning to remove oil, use dilute nitric acid solution to clean and remove rust, use deionized water and absolute ethanol to ultrasonically clean the impurities attached to the surface of the sintered NdFeB prefabricated magnets, blow Treat before drying.

[0052] Metal terbium and metal aluminum are used as targets, and metal terbium atoms and metal aluminum atoms are simultaneously sputtered onto the surface of the pretreated NdFeB magnet perpendicular to the direction of the easy magnetization axis to deposit aluminum-doped heavy rare earth films to obtain NdFeB magnets Blank, in the NdFeB magnet blank, the mass fraction of metal terbium is 0.24%, and the mass fraction of metal aluminum is 0.04%.

[0053] The sintered NdFeB prefabricated magnet formed with the aluminum-doped heavy rare earth film is subjected to diffusion treatment and tempering treatment in a vacuum heat treatment eq...

Embodiment 2

[0055] Embodiment 2 is carried out with reference to Embodiment 1, except that, in the NdFeB magnet blank, the mass fraction of aluminum is 0.07%.

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

PUM

No PUM Login to View More

Abstract

The invention relates to a preparation method of a neodymium-iron-boron magnet. The preparation method comprises the following steps: providing a neodymium-iron-boron prefabricated magnet; an aluminum-doped heavy rare earth film is formed on the surface of the neodymium-iron-boron prefabricated magnet, materials of the aluminum-doped heavy rare earth film comprise elemental aluminum and heavy rare earth, and a neodymium-iron-boron magnet blank is obtained; and the neodymium-iron-boron magnet blank is subjected to diffusion treatment and tempering treatment, and the neodymium-iron-boron magnet is obtained. According to the preparation method, the diffusion depth of the heavy rare earth can be increased, the utilization rate of the heavy rare earth is increased, the raw material cost of the neodymium-iron-boron magnet is reduced, and meanwhile, the coercive force and other magnetic properties of the iron-boron magnet are further improved.

Description

technical field [0001] The invention relates to the technical field of rare earth permanent magnet materials, in particular to a preparation method of an NdFeB magnet. Background technique [0002] NdFeB magnets have a high magnetic energy product, so they are widely used in electric vehicles, wind power generation, nuclear magnetic resonance and other fields. However, as the temperature increases, the magnetic properties of NdFeB magnets will decrease. Therefore, in order to improve The high temperature stability of NdFeB magnets needs to increase its coercive force. [0003] The grain boundary diffusion method can improve the coercive force of NdFeB magnets. The traditional grain boundary diffusion method usually sets a heavy rare earth film on the surface of the NdFeB prefabricated magnet, and then performs diffusion treatment and tempering treatment. However, the traditional grain boundary diffusion method , the diffusion depth of heavy rare earths is shallow, which lea...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

Application Information

Patent Timeline
no application Login to View More
Patent Type & Authority Applications(China)
IPC IPC(8): H01F1/057H01F41/02
CPCH01F41/0253H01F41/0293H01F41/0273H01F1/0577
Inventor 宋振纶杨丽景马照坤王庭辉郑必长
Owner NINGBO INST OF MATERIALS TECH & ENG CHINESE ACADEMY OF SCI