阅读说明：本技术 一种高性能钕铁硼永磁材料的制备方法 (Preparation method of high-performance neodymium iron boron permanent magnet material ) 是由 曹海荣 管群 林家深 于 2020-12-23 设计创作，主要内容包括：本发明公开了一种高性能钕铁硼永磁材料的制备方法。所述的永磁材料包含以下重量份原料：稀土金属钕29％-32％、硼铁合金0.85-1.2％,镝铁合金0.5-1.0％、铌0.2-0.45％、钴1.5-2.5％、锌0.18％-0.2％、镓0.3-0.5％、氧化铥超微粉末2.5-4％,余量为铁。本发明合理控制各个原料配比及含量,同时通过添加稀土元素,提高了磁体整体的最大磁能积,从而减小磁体的使用量,更加轻量化、价格成本低,本发明在烧结回火阶段进行严格的温度控制,能有效提高产物的磁性能。而且还能提高钕铁硼永磁材料的整体的矫顽力,使其具有改善方形度以及改善温度稳定性的优异性能。(The invention discloses a preparation method of a high-performance neodymium iron boron permanent magnet material. The permanent magnet material comprises the following raw materials in parts by weight: 29-32% of rare earth metal neodymium, 0.85-1.2% of ferroboron, 0.5-1.0% of dysprosium-iron alloy, 0.2-0.45% of niobium, 1.5-2.5% of cobalt, 0.18-0.2% of zinc, 0.3-0.5% of gallium, 2.5-4% of thulium oxide ultrafine powder and the balance of iron. The invention reasonably controls the proportion and the content of each raw material, simultaneously improves the integral maximum magnetic energy product of the magnet by adding the rare earth element, thereby reducing the usage amount of the magnet, having lighter weight and lower price cost. But also can improve the overall coercive force of the neodymium iron boron permanent magnet material, so that the neodymium iron boron permanent magnet material has excellent performances of improving the squareness and improving the temperature stability.)

1. A high performance neodymium iron boron permanent magnet material which characterized in that: the permanent magnet material comprises the following raw materials in parts by weight: 29-32% of rare earth metal neodymium, 0.85-1.2% of ferroboron, 0.5-1.0% of dysprosium-iron alloy, 0.2-0.45% of niobium, 1.5-2.5% of cobalt, 0.18-0.2% of zinc, 0.3-0.5% of gallium, 2.5-4% of thulium oxide ultrafine powder and the balance of iron.

2. The high-performance neodymium-iron-boron permanent magnet material according to claim 1, characterized in that: the high-performance neodymium iron boron permanent magnet material comprises the following raw materials in parts by weight: 30% of rare earth metal neodymium, 1% of ferroboron alloy, 0.55% of dysprosium-iron alloy, 0.3% of niobium, 1.8% of cobalt, 0.18% of zinc, 0.45% of gallium, 2.8% of thulium oxide superfine powder and the balance of iron.

3. The high-performance neodymium-iron-boron permanent magnet material according to claim 1, characterized in that: the weight ratio of boron to iron in the ferroboron alloy is 1: 4.

4. the high-performance neodymium-iron-boron permanent magnet material according to claim 1, characterized in that: the weight ratio of dysprosium to iron in the dysprosium-iron alloy is 1: 3.85.

5. a preparation method of a high-performance neodymium iron boron permanent magnet material is characterized by comprising the following steps: the preparation method comprises the following specific steps: step one, preparing the thulium oxide superfine powder, namely preparing the thulium hydroxide superfine powder in an ethanol solution, dispersing the generated thulium hydroxide in the ethanol solution immediately, and roasting the thulium hydroxide superfine powder to obtain the thulium oxide superfine powder;

step two, mixing materials, namely adding rare earth metal neodymium, niobium, cobalt, zinc, gallium and thulium oxide superfine powder and iron into a ferroboron alloy and a dysprosium iron alloy according to the mass percentage raw material ratio of the high-performance neodymium-iron-boron permanent magnet material, and uniformly mixing to form a mixture;

step three, casting, namely putting the mixture prepared in the step two into a vacuum induction smelting furnace, smelting under the condition of high-purity argon, pouring alloy liquid on a water-cooled copper roller with the linear speed of 3-5m/s after smelting, and quickly cooling to obtain a quick-setting alloy casting sheet with the average thickness of 0.25-0.5 mm;

step four, pulverizing, namely carrying out dehydrogenation for 4-8h after hydrogen crushing of the alloy cast sheet, and then grinding the powder to powder with the particle size of 5-8 microns by using an airflow mill;

step five, magnetizing and compacting, namely putting the powder into a forming press die under the protection of inert gas, adding a magnetic field for orientation, and pressing and forming after orientation; carrying out static pressure for 2-2.5 hours to obtain a green body;

step six, sintering and tempering, namely putting the molded green body into a microwave vacuum sintering furnace for sintering, wherein the sintering temperature is 1060-1200 ℃; high-temperature tempering: firstly, heating the sintered magnet block to 950-; then heating to 850-955 ℃, then extracting for cooling, and then tempering at 580-605 ℃; low-temperature tempering: tempering at 560-620 ℃, and then discharging and cooling to room temperature;

step seven: and packaging and warehousing after inspection.

Technical Field

The invention belongs to the field of permanent magnet materials, and particularly relates to a preparation method of a high-performance neodymium iron boron permanent magnet material.

Background

The ndfeb magnet is a permanent magnet having the strongest magnetic force so far. The neodymium iron boron is called as a third-generation rare earth permanent magnetic material, is a permanent magnetic material with the highest magnetic energy product at present, and with the development of industries such as computers, communication and the like, the preparation and application of the NdFeB permanent magnetic material are developed rapidly. Its application can greatly reduce volume and mass of whole machine, for example, it can be used in magnetic disk, and can make magnetic disk drive be miniaturized, and its performance is better. Among sound devices, neodymium iron boron is widely applied to micro speakers, earphones and speakers of high-grade automobiles, and the fidelity and the signal to noise ratio of the sound are greatly improved. In addition, the magnetic resonance imaging system can be applied to direct current motors and nuclear magnetic resonance imaging, and particularly has the characteristics of large quantity, high-speed transportation, safety, reliability, low noise and the like when being applied to magnetic suspension trains. Dual high magnetic performance magnets (high magnetic energy product (BH) max and high intrinsic coercivity Hcj) and reduced production cost are major goals of development depending on the application. Therefore, how to obtain a comprehensive magnetic material with higher performance of the magnet at the lowest cost can become a problem which needs to be solved urgently at present.

Disclosure of Invention

The invention aims to provide a preparation method of a high-performance neodymium iron boron permanent magnet material.

In order to achieve the purpose, the invention provides the following technical scheme: a high-performance neodymium iron boron permanent magnet material comprises the following raw materials in parts by weight: 29-32% of rare earth metal neodymium, 0.85-1.2% of ferroboron, 0.5-1.0% of dysprosium-iron alloy, 0.2-0.45% of niobium, 1.5-2.5% of cobalt, 0.18-0.2% of zinc, 0.3-0.5% of gallium, 2.5-4% of thulium oxide ultrafine powder and the balance of iron.

Preferably, the high-performance neodymium iron boron permanent magnet material comprises the following raw materials in parts by weight: 30% of rare earth metal neodymium, 1% of ferroboron alloy, 0.55% of dysprosium-iron alloy, 0.3% of niobium, 1.8% of cobalt, 0.18% of zinc, 0.45% of gallium, 2.8% of thulium oxide superfine powder and the balance of iron.

Preferably, the weight ratio of boron to iron in the ferroboron alloy is 1: 4.

preferably, the weight ratio of dysprosium to iron in the dysprosium-iron alloy is 1: 3.85.

a preparation method of a high-performance neodymium iron boron permanent magnet material comprises the following steps: step one, preparing the thulium oxide superfine powder, namely preparing the thulium hydroxide superfine powder in an ethanol solution, dispersing the generated thulium hydroxide in the ethanol solution immediately, and roasting the thulium hydroxide superfine powder to obtain the thulium oxide superfine powder;

step two, mixing materials, namely adding rare earth metal neodymium, niobium, cobalt, zinc, gallium and thulium oxide superfine powder and iron into a ferroboron alloy and a dysprosium iron alloy according to the mass percentage raw material ratio of the high-performance neodymium-iron-boron permanent magnet material, and uniformly mixing to form a mixture;

step three, casting, namely putting the mixture prepared in the step two into a vacuum induction smelting furnace, smelting under the condition of high-purity argon, pouring alloy liquid on a water-cooled copper roller with the linear speed of 3-5m/s after smelting, and quickly cooling to obtain a quick-setting alloy casting sheet with the average thickness of 0.25-0.5 mm;

step four, pulverizing, namely carrying out dehydrogenation for 4-8h after hydrogen crushing of the alloy cast sheet, and then grinding the powder to powder with the particle size of 5-8 microns by using an airflow mill;

step five, magnetizing and compacting, namely putting the powder into a forming press die under the protection of inert gas, adding a magnetic field for orientation, and pressing and forming after orientation; carrying out static pressure for 2-2.5 hours to obtain a green body;

step six, sintering and tempering, namely putting the molded green body into a microwave vacuum sintering furnace for sintering, wherein the sintering temperature is 1060-1200 ℃; high-temperature tempering: firstly, heating the sintered magnet block to 950-; then heating to 850-955 ℃, then extracting for cooling, and then tempering at 580-605 ℃; low-temperature tempering: tempering at 560-620 ℃, and then discharging and cooling to room temperature;

step seven: and packaging and warehousing after inspection.

Compared with the prior art, the invention has the following beneficial effects: the invention reasonably controls the proportion and the content of each raw material, simultaneously improves the integral maximum magnetic energy product of the magnet by adding the rare earth element, thereby reducing the usage amount of the magnet, having lighter weight and lower price cost. But also can improve the overall coercive force of the neodymium iron boron permanent magnet material, so that the neodymium iron boron permanent magnet material has excellent performances of improving the squareness and improving the temperature stability.

Description of the drawings:

FIG. 1 is a schematic diagram of the preparation process of the present invention.

Detailed Description

The technical solutions of the present invention will be described clearly and completely in the following embodiments of the present invention, and it should be understood that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Example 1

A preparation method of a high-performance neodymium iron boron permanent magnet material comprises the following steps: step one, preparing the thulium oxide superfine powder, namely preparing the thulium hydroxide superfine powder in an ethanol solution, dispersing the generated thulium hydroxide in the ethanol solution immediately, and roasting the thulium hydroxide superfine powder to obtain the thulium oxide superfine powder;

step two, mixing materials, namely adding 29 percent of rare earth metal neodymium, 0.2 percent of niobium, 1.5 percent of cobalt, 0.18 percent of zinc, 0.3 percent of gallium, 2.5 percent of thulium oxide superfine powder and the balance of iron into 0.85 percent of ferroboron and 0.5 percent of dysprosium-iron alloy according to the mass percent ratio of the high-performance neodymium-iron-boron permanent magnet material to form a mixture;

step three, casting, namely putting the mixture prepared in the step two into a vacuum induction smelting furnace, smelting under the condition of high-purity argon, pouring alloy liquid on a water-cooled copper roller with the linear speed of 3m/s after smelting, and quickly cooling to obtain a quick-setting alloy casting sheet with the average thickness of 0.25 mm;

step four, pulverizing, namely carrying out dehydrogenation for 4 hours after hydrogen crushing of the alloy cast sheet, and then grinding the powder to powder with the particle size of 5-8 microns by using an airflow mill;

step five, magnetizing and compacting, namely putting the powder into a forming press die under the protection of inert gas, adding a magnetic field for orientation, and pressing and forming after orientation; carrying out static pressure for 2 hours to obtain a green body;

step six, sintering and tempering, namely putting the molded green body into a microwave vacuum sintering furnace for sintering, wherein the sintering temperature is 1060-1200 ℃; high-temperature tempering: firstly, heating the sintered magnet block to 950-; then heating to 850-955 ℃, then extracting for cooling, and then tempering at 580-605 ℃; low-temperature tempering: tempering at 560-620 ℃, and then discharging and cooling to room temperature;

step seven: and packaging and warehousing after inspection.

Example 2

A preparation method of a high-performance neodymium iron boron permanent magnet material comprises the following steps: step one, preparing the thulium oxide superfine powder, namely preparing the thulium hydroxide superfine powder in an ethanol solution, dispersing the generated thulium hydroxide in the ethanol solution immediately, and roasting the thulium hydroxide superfine powder to obtain the thulium oxide superfine powder;

step two, mixing materials, namely adding 32% of rare earth metal neodymium, 0.45% of niobium, 2.5% of cobalt, 0.2% of zinc, 0.5% of gallium, 4% of thulium oxide ultrafine powder and the balance iron into 1.2% of the ferroboron alloy and 1.0% of the dysprosium iron alloy according to the mass percentage ratio of the high-performance neodymium-iron-boron permanent magnet material, and uniformly mixing to form a mixture;

step three, casting, namely putting the mixture prepared in the step two into a vacuum induction smelting furnace, smelting under the condition of high-purity argon, pouring alloy liquid on a water-cooled copper roller with the linear speed of 5m/s after smelting, and quickly cooling to obtain a quick-setting alloy casting sheet with the average thickness of 0.35 mm;

step four, pulverizing, namely carrying out dehydrogenation for 8 hours after hydrogen crushing of the alloy cast sheet, and then grinding the powder to powder with the particle size of 8 microns by using an airflow mill;

step five, magnetizing and compacting, namely putting the powder into a forming press die under the protection of inert gas, adding a magnetic field for orientation, and pressing and forming after orientation; carrying out static pressure for 2.5 hours to obtain a green body;

step six, sintering and tempering, namely putting the molded green body into a microwave vacuum sintering furnace for sintering, wherein the sintering temperature is 1060-1200 ℃; high-temperature tempering: firstly, heating the sintered magnet block to 950-; then heating to 850-955 ℃, then extracting for cooling, and then tempering at 580-605 ℃; low-temperature tempering: tempering at 560-620 ℃, and then discharging and cooling to room temperature;

step seven: and packaging and warehousing after inspection.

Example 3

A preparation method of a high-performance neodymium iron boron permanent magnet material comprises the following steps: step one, preparing the thulium oxide superfine powder, namely preparing the thulium hydroxide superfine powder in an ethanol solution, dispersing the generated thulium hydroxide in the ethanol solution immediately, and roasting the thulium hydroxide superfine powder to obtain the thulium oxide superfine powder;

step two, mixing materials, namely adding 30% of rare earth metal neodymium, 0.3% of niobium, 1.8% of cobalt, 0.19% of zinc, 0.45% of gallium, 3% of thulium oxide ultrafine powder and the balance of iron into 1% of ferroboron alloy and 0.8% of dysprosium alloy according to the mass percentage ratio of the high-performance neodymium-iron-boron permanent magnet material, and uniformly mixing to form a mixture;

step three, casting, namely putting the mixture prepared in the step two into a vacuum induction smelting furnace, smelting under the condition of high-purity argon, pouring alloy liquid on a water-cooled copper roller with the linear speed of 4m/s after smelting, and quickly cooling to obtain a quick-setting alloy casting sheet with the average thickness of 0.5 mm;

step four, pulverizing, namely carrying out dehydrogenation for 4-8h after hydrogen crushing of the alloy cast sheet, and then grinding the powder to powder with the particle size of 7 microns by using an airflow mill;

step five, magnetizing and compacting, namely putting the powder into a forming press die under the protection of inert gas, adding a magnetic field for orientation, and pressing and forming after orientation; obtaining a green body after static pressure is carried out for 2.2 hours;

step six, sintering and tempering, namely putting the molded green body into a microwave vacuum sintering furnace for sintering, wherein the sintering temperature is 1060-1200 ℃; high-temperature tempering: firstly, heating the sintered magnet block to 950-; then heating to 850-955 ℃, then extracting for cooling, and then tempering at 580-605 ℃; low-temperature tempering: tempering at 560-620 ℃, and then discharging and cooling to room temperature;

step seven: and packaging and warehousing after inspection.

The experimental example is the high performance neodymium iron boron permanent magnet material prepared in examples 1-3;

comparative example 1: the permanent magnet material in the comparison material only contains 30% of neodymium, 2.5% of boron and the balance of iron.

Comparative example 2 a nd-fe-b permanent magnet material, the permanent magnet material in this comparative material only contains 35% nd, 2.8% b, the remainder is iron.

Performance test subjects: the high-performance neodymium iron boron permanent magnet materials obtained in examples 1-3 were used as test samples 1-3, and the neodymium iron boron permanent magnet materials were used as comparative examples 1-2.

The test method comprises the following steps: the test sample 1-3 and the comparison sample 1-2 are made into standard samples according to the specification of GB/T13560-2017 sintered Nd-Fe-B permanent magnet, and the coercive force (Hcj), remanence (Br) and magnetic energy product (BH) of the Nd-Fe-B magnet are measured according to the method in the standard. The test results are shown in Table 1.

TABLE 1

Therefore, the high-performance neodymium iron boron permanent magnet materials of the embodiments 1 to 3 have better performances in the aspects of coercive force, remanence and the like.

Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that changes, modifications, substitutions and alterations can be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents.