阅读说明：本技术 钕铁硼合金粉末、钕铁硼磁体材料及制备方法和应用 (Neodymium-iron-boron alloy powder, neodymium-iron-boron magnet material, and preparation method and application thereof ) 是由 牟维国 韦兴 张志琦 黄清芳 许德钦 范宇峰 于 2019-11-28 设计创作，主要内容包括：本发明公开了钕铁硼合金粉末、钕铁硼磁体材料及制备方法和应用。其中,钕铁硼合金粉末,以质量百分比计,其包括以下含量的组分：R：29.5～31.5wt％,R为稀土元素,R中至少包括Nd；B：0.85～0.92wt％,S：0.1～0.5wt％,Fe：64～68wt％；N：0.2～0.6wt％；N包括Zr、Nb、Hf和Ti中的一种或多种；N与S的质量比为(1～4.1)：1,其中S来源于硫单质和/或氧化硫。采用该钕铁硼合金粉末得到的钕铁磁体材料在减少了重稀土元素的使用甚至不添加重稀土元素的情况下,仍然能显著的提高磁体材料的矫顽力和剩磁。(The invention discloses neodymium iron boron alloy powder, a neodymium iron boron magnet material, a preparation method and application. The neodymium iron boron alloy powder comprises the following components in percentage by mass: r: 29.5-31.5 wt%, R is a rare earth element, and R at least comprises Nd; b: 0.85-0.92 wt%, S: 0.1-0.5 wt%, Fe: 64-68 wt%; n: 0.2-0.6 wt%; n comprises one or more of Zr, Nb, Hf and Ti; the mass ratio of N to S is (1-4.1): 1, wherein S is derived from elemental sulfur and/or sulfur oxide. The neodymium-iron magnet material obtained by adopting the neodymium-iron-boron alloy powder can still obviously improve the coercive force and remanence of the magnet material under the condition of reducing the use of heavy rare earth elements or even not adding the heavy rare earth elements.)

1. The neodymium-iron-boron alloy powder is characterized by comprising the following components in percentage by mass: r: 29.5-31.5 wt%, wherein R is a rare earth element, and at least comprises Nd;

Fe：64～68wt％；

B：0.85～0.92wt％；

S：0.1～0.5wt％；

n: 0.2-0.6 wt%; the N comprises one or more of Zr, Nb, Hf and Ti; the mass ratio of N to S is (1-4.1): 1;

the S is derived from elemental sulfur and/or sulfur oxide.

2. The ndfeb alloy powder according to claim 1, wherein the content of R is 30.5 to 31 wt%, more preferably 30.84 wt%, 30.86 wt% or 30.9 wt%;

and/or, the R also comprises light rare earth elements, preferably Pr;

and/or, the R also comprises heavy rare earth elements; preferably, the content of the heavy rare earth element is less than 3.5 wt%, preferably 0.4 to 3.5 wt%, and more preferably 1.4 to 3 wt%; wherein the heavy rare earth element species include Dy and/or Tb, preferably Dy and/or Tb;

and/or the Nd is present in an amount of 28 to 31 wt%, for example 28.46 wt%, 29.46 wt%, 30.44 wt% or 30.9 wt%, preferably 28 to 30 wt%;

and/or the Fe content is 65-67 wt%, preferably 65.96 wt%, 66.02 wt%, 66.05 wt%, 66.06 wt%, 66.08 wt% or 66.13 wt%;

and/or the content of B is 0.9-0.92 wt%, preferably 0.92 wt%;

and/or the S content is 0.11-0.45 wt%, preferably 0.11 wt%, 0.21 wt%, 0.22 wt%, 0.36 wt% or 0.45 wt%;

and/or the particle size of the sulfur simple substance is 10-200 nm, preferably 12nm, 50nm, 100nm or 200 nm;

and/or, the sulfur oxide is sulfur dioxide;

and/or the mass ratio of N to S is (3-4.1): 1;

and/or the content of N is 0.3-0.5 wt%, preferably 0.3 wt%, 0.4 wt% or 0.5 wt%; preferably, the N is one or more of Zr, Nb, Hf and Ti, more preferably Zr and/or Ti; wherein, the Zr content is preferably 0.3 to 0.5 wt%, such as 0.3 wt%, 0.4 wt% or 0.5 wt%, and the Ti content is preferably 0.3 to 0.5 wt%, such as 0.3 wt%;

and/or, the neodymium iron boron alloy powder also comprises Cu; preferably, the Cu content is 0.05 to 0.25 wt%, preferably 0.05 to 0.15 wt%, more preferably 0.05 wt% or 0.1 wt%;

and/or, the neodymium iron boron alloy powder also comprises Co; preferably, the content of Co is 0.5 to 2 wt%, preferably 0.5 to 1.5 wt%, more preferably 0.5 wt% or 1 wt%;

and/or, the neodymium iron boron alloy powder also comprises Ga; preferably, the content of Ga is 0.20 to 0.3 wt%, preferably 0.22 to 0.28 wt%;

and/or, the neodymium iron boron alloy powder also comprises Al; preferably, the Al content is 0.2-0.4 wt%, preferably 0.25-0.35 wt%, more preferably 0.25 wt% or 0.3 wt%.

3. The ndfeb alloy powder according to claim 1 or 2, comprising the following components in mass percent: r: 29.5 to 31.5 wt%, Fe: 64-68 wt%, B: 0.85-0.92 wt%, S: 0.1-0.5 wt%, Cu: 0.05 to 0.25 wt%, Co: 0.5 to 2 wt%, Ga: 0.2-0.3 wt%, Al: 0.2-0.4 wt%, N: 0.2-0.6 wt%, wherein the N comprises one or more of Zr, Nb, Hf and Ti, and the mass ratio of the N to the S is (1-4.1): 1, the S is derived from elemental sulfur and/or sulfur oxide; the rare earth element R is a rare earth element, the R comprises Nd and RH, the RH is a heavy rare earth element, the content of the heavy rare earth element is 0.4-3.5 wt%, and the content of the Nd is 28-31 wt%;

preferably, the neodymium iron boron alloy powder comprises the following components in percentage by mass: r: 30.5-31 wt%, Fe: 65-67 wt%, B: 0.9-0.92 wt%, S: 0.11-0.45 wt%, Cu: 0.05-0.15 wt%; co: 0.5 to 1.5 wt%, Ga: 0.22-0.28 wt%, Al: 0.25 to 0.35 wt%, N: 0.3-0.5 wt%, wherein the N comprises one or more of Zr, Nb, Hf and Ti, and the mass ratio of the N to the S is (1-4.1): 1, the S is derived from elemental sulfur and/or sulfur oxide; the rare earth element R is a rare earth element, the R comprises Nd and RH, the RH is a heavy rare earth element, the content of the heavy rare earth element is 1.4-3 wt%, and the content of the Nd is 28-30 wt%; the heavy rare earth element species include Dy and/or Tb.

4. The preparation method of the neodymium iron boron magnet material is characterized by comprising the following steps: forming, sintering and heat-treating the neodymium-iron-boron alloy powder according to any one of claims 1 to 3; the sintering temperature is 1065-1100 ℃;

preferably, when the S is derived from elemental sulfur, the elemental sulfur is added after the airflow milling treatment and before the molding, and the adding mode is preferably mixing with the material after the airflow milling treatment; preferably, when said S is derived from sulphur oxide, said sulphur oxide is added in the jet milling process.

5. The method according to claim 4, wherein the mixing is carried out in a three-dimensional blender, preferably for a time of 2 to 4 hours;

and/or, when the sulfur oxide is gas, the flow rate of the sulfur oxide introduced into the airflow milling chamber is preferably 35-71 ml/min;

and/or, hydrogen breaking treatment is also included before the airflow grinding treatment; preferably, the hydrogen breaking treatment is performed under the conditions that the neodymium iron boron alloy cast sheet is saturated to absorb hydrogen under the hydrogen pressure of 0.067-0.098 MPa, and is dehydrogenated at 480-530 ℃, and more preferably saturated to absorb hydrogen under the hydrogen pressure of 0.08MPa and is dehydrogenated at 500 ℃; preferably, the thickness of the neodymium iron boron alloy cast sheet is 0.28-0.4 mm, and more preferably 0.3 mm;

and/or the particle size of the neodymium iron boron alloy powder after the airflow milling treatment is 3.9-4.2 μm, preferably 4.0-4.2 μm;

and/or the oxygen content in the milling chamber of the jet mill in the jet milling treatment is below 15 ppm;

and/or the rotating speed of the sorting wheel in the jet milling treatment is 3500-4300 rpm/min, preferably 4000 rpm/min;

and/or, the molding is performed in an orientation molding in a magnetic field above 1.8T, preferably in a magnetic field of 1.8-2.5T;

and/or the sintering temperature is 1070-1090 ℃, preferably 1070 ℃ or 1080 ℃;

and/or the sintering time is 4-7 h, preferably 6 h;

and/or the temperature of the heat treatment is 460-520 ℃, preferably 500 ℃;

and/or the time of the heat treatment is 4-10 hours, preferably 6 hours.

6. A neodymium-iron-boron magnet material, characterized by being prepared by the preparation method as claimed in claim 4 or 5.

7. The neodymium-iron-boron magnet material is characterized by comprising the following components in percentage by mass: r: 29.5 to 31.5 wt%;

Fe：64～68wt％；

B：0.85～0.92wt％；

S：0.095～0.5wt％；

n: 0.2-0.6 wt%, wherein the N comprises one or more of Zr, Nb, Hf and Ti, and the mass ratio of the N to the S is (1-4.1): 1;

the R is a rare earth element and at least comprises Nd;

preferably, the R also comprises heavy rare earth elements.

8. The ndfeb magnet material as claimed in claim 7, wherein R is 30.5 to 31 wt%, preferably 30.83 wt%, 30.84 wt%, 30.85 wt%, 30.86 wt% or 30.91 wt%;

and/or, the R also comprises light rare earth elements, preferably Pr;

and/or the Nd is present in an amount of 28 to 31 wt%, preferably 28.44 wt%, 28.45 wt%, 28.46 wt%, 28.47 wt%, 29.44 wt%, 30.43 wt% or 30.91 wt%;

and/or the content of the heavy rare earth element is less than 3.5 wt%, preferably 0.42 wt%, 1.41 wt%, 2.38 wt%, 2.39 wt%, 2.4 wt% or 2.41 wt%;

and/or, the heavy rare earth element species include Dy and/or Tb, preferably Dy and/or Tb;

and/or the content of Fe is 65-67 wt%, preferably 65.773 wt%, 65.875 wt%, 65.92 wt%, 65.962 wt%, 65.963 wt%, 65.964 wt%, 65.976 wt%, 65.989 wt%, 66.041 wt% or 66.136 wt%;

and/or the content of B is 0.9-0.92 wt%, preferably 0.92 wt%;

and/or the S content is 0.095 to 0.445 wt%, preferably 0.098 wt%, 0.099 wt%, 0.101 wt%, 0.105 wt%, 0.204 wt%, 0.211 wt%, 0.355 wt% or 0.443 wt%;

and/or, said S is Nd₂S₃In the form of said neodymium-iron-boron magnet material; preferably, the Nd₂S₃The content of (a) is 0.49-2.85 wt% of the total mass of the neodymium iron boron magnet material, such as 0.523 wt%, 2.087 wt% or 2.641 wt%;

and/or the mass ratio of N to S is (3-4.1): 1;

and/or the content of N is 0.3-0.5 wt%, preferably 0.3 wt%, 0.4 wt% or 0.5 wt%;

and/or the N is one or more of Zr, Nb, Hf and Ti, preferably Zr and/or Ti; wherein, the Zr content is preferably 0.3 to 0.5 wt%, such as 0.3 wt%, 0.4 wt% or 0.5 wt%, and the Ti content is preferably 0.3 to 0.5 wt%, such as 0.3 wt%;

and/or, the neodymium iron boron magnet material also comprises Cu; preferably, the content of Cu is 0.05 to 0.15 wt%, preferably 0.05 wt% or 0.1 wt%;

and/or, the neodymium iron boron magnet material also comprises Co; preferably, the content of Co is 0.5 to 2 wt%, preferably 0.5 to 1.5 wt%, more preferably 0.5 wt% or 1 wt%;

and/or, the neodymium iron boron magnet material also comprises Ga; preferably, the content of Ga is 0.20 to 0.3 wt%, preferably 0.22 to 0.28 wt%, more preferably 0.25 wt% or 0.3 wt%;

and/or, the neodymium iron boron magnet material also comprises Al; preferably, the Al content is 0.2-0.4 wt%, preferably 0.25-0.35 wt%, more preferably 0.2 wt%, 0.25 wt% or 0.3 wt%;

and/or, the neodymium iron boron magnet material also comprises O; preferably, the content of O is less than 0.12 wt%, preferably less than 0.11 wt%.

9. The neodymium-iron-boron magnet material as claimed in claim 7 or 8, characterized by comprising the following components in percentage by mass: r: 29.5 to 31.5 wt%, Fe: 64-68 wt%, B: 0.85-0.92 wt%, Cu: 005 to 0.25 wt%, Co: 0.5 to 2 wt%, Ga: 0.2-0.3 wt%, Al: 0.2-0.4 wt%, S: 0.095-0.5 wt%, O is less than or equal to 0.12 wt%, N: 0.2-0.6 wt%, wherein the N comprises one or more of Zr, Nb, Hf and Ti, and the mass ratio of the N to the S is (1-4.1): 1; the rare earth element R is a rare earth element, the R comprises Nd and RH, the RH is a heavy rare earth element, the content of the heavy rare earth element is 0.4-3.5 wt%, and the content of the Nd is 28-31 wt%; wherein the heavy rare earth element preferably includes Dy and/or Tb; s is preferably Nd₂S₃Preferably, said Nd is present₂S₃The content of the component (A) is 0.49-2.85 wt% of the total mass of the neodymium iron boron magnet material, and the percentage is that the mass of each component accounts for the total mass of the neodymium iron boron magnet material;

more preferably, the neodymium iron boron magnet material comprises the following components in percentage by mass: r: 30.5-31 wt%, Fe: 65-67 wt%, B: 0.9-0.92 wt%, Cu: 0.05-0.15 wt%, Co: 0.5 to 1.5 wt%, Ga: 0.22-0.28 wt%, Al: 0.25 to 0.35 wt%, S: 0.095-0.45 wt%, O is less than or equal to 0.11 wt%, N: 0.3-0.5 wt%, wherein the N comprises Zr and/or Ti, and the mass ratio of the N to the S is (1-4.1): 1; the rare earth element R is a rare earth element, the R comprises Nd and RH, the RH is a heavy rare earth element, the content of the heavy rare earth element is 1.4-3 wt%, and the content of the Nd is 28-30 wt%; the heavy rare earth element species preferably include Dy and/or Tb; wherein S is preferably Nd₂S₃Is present in the form of said Nd₂S₃The content of (b) is preferably 0.52-2.65 wt% of the total mass of the neodymium iron boron magnet material, and the percentage is the percentage of the mass of each component in the total mass of the neodymium iron boron magnet material.

10. Use of a neodymium-iron-boron magnet material according to any one of claims 6-9 as an electronic component in an electrical machine; the motor is preferably a new energy automobile driving motor, an air conditioner compressor or an industrial servo motor, a wind driven generator, an energy-saving elevator or a loudspeaker assembly.

Technical Field

The invention particularly relates to neodymium iron boron alloy powder, a neodymium iron boron magnet material, a preparation method and application.

Background

By Nd₂Fe₁₄The neodymium iron boron (NdFeB) magnet material with the B as the main component has higher remanence, coercive force and maximum magnetic energy product, has excellent comprehensive magnetic performance, and is applied to the aspects of wind power generation, new energy automobiles, variable frequency household appliances and the like. Because heavy rare earth elements Dy and Tb have irreplaceable effects in high-performance sintered neodymium iron boron, but because the heavy rare earth elements are high in price and limited in reserves, a way of improving the coercive force of a sintered neodymium iron boron magnet by using no or less heavy rare earth is needed to be found.

Chinese patent document CN108155004A discloses a high-performance sintered neodymium iron boron magnet, which is a neodymium iron boron magnet material with good performance obtained by combining sulfur and low-melting-point metal, but the remanence and the coercive force are still low. In the patent, only sulfur with the content lower than 1000ppm can be added to improve the performance of the magnet material, and when the content is higher than 1000ppm, the remanence is reduced, and the advantage that the sulfur can improve the performance of the neodymium iron boron magnet material cannot be fully utilized.

Disclosure of Invention

The invention aims to solve the technical problems that only a small amount of sulfur can be added to improve the coercive force of a magnet, the performance of a magnet material cannot be obviously improved and a large amount of heavy rare earth elements need to be added in the prior art. The neodymium iron boron alloy powder, the neodymium iron boron magnet material, the preparation method and the application are provided. The neodymium iron boron magnet material can still obviously provide the coercive force and remanence of the magnet material under the condition of reducing the use of heavy rare earth elements and even not adding the heavy rare earth elements.

The invention solves the technical problems through the following technical scheme.

The invention provides neodymium iron boron alloy powder which comprises the following components in percentage by mass: r: 29.5-31.5 wt%, wherein R is a rare earth element, and at least comprises Nd;

Fe：64～68wt％；

B：0.85～0.92wt％；

S：0.1～0.5wt％；

n: 0.2-0.6 wt%; the N comprises one or more of Zr, Nb, Hf and Ti; the mass ratio of N to S is (1-4.1): 1;

the S is derived from elemental sulfur and/or sulfur oxide.

In the invention, the content of R is preferably 30.5 to 31 wt%, for example 30.84 wt%, 30.86 wt% or 30.9 wt%, and the percentage is the percentage of the mass of each component in the total mass of the neodymium iron boron alloy powder.

In the present invention, the R may further include a light rare earth element, such as Pr, which is conventional in the art.

In the invention, the R may further include a heavy rare earth element that is conventional in the art, and the content of the heavy rare earth element is preferably less than 3.5 wt%, more preferably 0.4 to 3.5 wt%, for example 0.4 wt%, 1.4 wt% or 2.4 wt%, more preferably 1.4 to 3 wt%, where the percentage is the percentage of the mass of each component in the total mass of the neodymium iron boron alloy powder.

In the present invention, the heavy rare earth element preferably includes Dy and/or Tb, more preferably Dy and/or Tb.

In the present invention, the content of Nd is preferably 28 to 31 wt%, for example, 28.46 wt%, 29.46 wt%, 30.44 wt% or 30.9 wt%, and more preferably 28 to 30 wt%, where the percentage is the percentage of the mass of each component in the total mass of the neodymium iron boron alloy powder.

In the present invention, the content of Fe is preferably 65 to 67 wt%, for example, 65.96 wt%, 66.02 wt%, 66.06 wt%, 66.08 wt% or 66.13 wt%, where the percentage is the percentage of the mass of each component in the total mass of the neodymium iron boron alloy powder.

In the invention, the content of B is preferably 0.9 to 0.92 wt%, for example 0.92 wt%, and the percentage is the percentage of the mass of each component in the total mass of the neodymium iron boron magnet material.

In the present invention, the content of S is preferably 0.11 to 0.45 wt%, for example, 0.11 wt%, 0.21 wt%, 0.22 wt%, 0.36 wt% or 0.45 wt%, and the percentage is the percentage of the mass of each component in the total mass of the neodymium iron boron alloy powder.

In the present invention, the elemental sulfur is generally in the form of powder, and the particle size of the elemental sulfur in the form of powder is preferably 10 to 200nm, such as 12nm, 50nm, 100nm or 200nm, as known to those skilled in the art.

In the present invention, the sulfur oxide is preferably sulfur dioxide.

In the present invention, the mass ratio of N to S may be, for example, 0.4:0.11, 0.4:0.21, 0.3:0.22, 0.4:0.36 or 0.5:0.45, preferably (3 to 4.1): 1.

in the present invention, the content of N is preferably 0.3 to 0.5 wt%, for example, 0.3 wt%, 0.4 wt% or 0.5 wt%, and the percentage is the percentage of the mass of each component in the total mass of the neodymium iron boron alloy powder.

In the present invention, the kind of N is preferably one or more of Zr, Nb, Hf and Ti, for example Zr and/or Ti.

Wherein the Zr content is preferably 0.3 to 0.5 wt%, such as 0.3 wt%, 0.4 wt% or 0.5 wt%.

Wherein, the content of Ti is preferably 0.3 to 0.5 wt%, for example 0.3 wt%.

In the present invention, the neodymium iron boron alloy powder may preferably further include Cu.

Wherein, the content of Cu is preferably 0.05 to 0.25 wt%, more preferably 0.05 to 0.15 wt%, for example 0.05 wt% or 0.1 wt%, and the percentage is the percentage of the mass of each component in the total mass of the neodymium iron boron alloy powder.

In the present invention, the neodymium iron boron alloy powder may preferably further include Co.

Wherein, the content of Co is preferably 0.5 to 2 wt%, more preferably 0.5 to 1.5 wt%, for example 0.5 wt% or 1 wt%, and the percentage is the percentage of the mass of each component in the total mass of the neodymium iron boron alloy powder.

In the present invention, the neodymium iron boron alloy powder may preferably further include Ga.

Wherein, the content of Ga is preferably 0.20 to 0.3 wt%, for example 0.25 wt% or 0.3 wt%, more preferably 0.22 to 0.28 wt%, and the percentage is the percentage of the mass of each component in the total mass of the neodymium iron boron alloy powder.

In the present invention, the neodymium iron boron alloy powder may preferably further include Al.

Wherein, the content of Al is preferably 0.2 to 0.4 wt%, more preferably 0.25 to 0.35 wt%, for example 0.25 wt% or 0.3 wt%, and the percentage is the percentage of the mass of each component in the total mass of the neodymium iron boron alloy powder.

In the invention, the neodymium iron boron alloy powder preferably comprises the following components in percentage by mass: r: 29.5 to 31.5 wt%, Fe: 64-68 wt%, B: 0.85-0.92 wt%, S: 0.1-0.5 wt%, Cu: 0.05 to 0.25 wt%, Co: 0.5 to 2 wt%, Ga: 0.2-0.3 wt%, Al: 0.2-0.4 wt%, N: 0.2-0.6 wt%, wherein the N comprises one or more of Zr, Nb, Hf and Ti, and the mass ratio of the N to the S is (1-4.1): 1, the S is derived from elemental sulfur and/or sulfur oxide; the rare earth element R is a rare earth element, the R comprises Nd and RH, the RH is a heavy rare earth element, the content of the heavy rare earth element is 0.4-3.5 wt%, and the content of the Nd is 28-31 wt%; the percentage is that the mass of each component accounts for the total mass of the neodymium iron boron alloy powder; wherein the heavy rare earth element preferably includes Dy and/or Tb, and the sulfur oxide is preferably sulfur dioxide.

In the invention, the neodymium iron boron alloy powder preferably comprises the following components in percentage by mass: r: 30.5-31 wt%, Fe: 65-67 wt%, B: 0.9-0.92 wt%, S: 0.11-0.45 wt%, Cu: 0.05-0.15 wt%; co: 0.5 to 1.5 wt%, Ga: 0.22-0.28 wt%, Al: 0.25 to 0.35 wt%, N: 0.3-0.5 wt%, wherein the N comprises one or more of Zr, Nb, Hf and Ti, and the mass ratio of the N to the S is (1-4.1): 1, the S is derived from elemental sulfur and/or sulfur oxide; the rare earth element R is a rare earth element, the R comprises Nd and RH, the RH is a heavy rare earth element, the content of the heavy rare earth element is 1.4-3 wt%, and the content of the Nd is 28-30 wt%; the percentage is that the mass of each component accounts for the total mass of the neodymium iron boron alloy powder; wherein the heavy rare earth element preferably includes Dy and/or Tb, and the sulfur oxide is preferably sulfur dioxide.

In the invention, the percentage is the mass percentage of each component in the total mass of the neodymium iron boron alloy powder.

The invention provides a preparation method of a neodymium iron boron magnet material, which comprises the following steps: forming, sintering and heat treating the neodymium iron boron alloy powder; the sintering temperature is 1065-1100 ℃.

In the present invention, when the S is derived from elemental sulfur, the elemental sulfur is preferably added after the air-milling treatment and before the molding.

Wherein the adding mode is generally mixing with the material after being treated by the air flow mill. The mixing is preferably carried out in a three-dimensional blender.

Wherein the mixing time is preferably 2-4 h, such as 3 h.

In the present invention, when the S is derived from sulfur oxide, the sulfur oxide is preferably added in the air-milling treatment. Those skilled in the art know that the equipment that is typically subjected to a jet mill process is a jet mill.

Wherein, when the sulfur oxide is a gas, the flow rate of the sulfur oxide into the air flow grinding chamber is preferably 35-71 ml/min, such as 35ml/min or 71 ml/min. Preferably, the introduction of sulphur oxide is continued throughout the duration of the jet milling treatment.

In the present invention, it is known to those skilled in the art that a hydrogen decrepitation treatment is usually further included before the air stream milling treatment.

The operation and conditions of the hydrogen breaking treatment can be conventional in the art, and typically, the neodymium iron boron alloy cast sheet is saturated and absorbs hydrogen under the hydrogen pressure of 0.067-0.098 MPa, and is dehydrogenated within 480-530 ℃, for example, saturated and absorbs hydrogen under the hydrogen pressure of 0.08MPa and is dehydrogenated within 500 ℃.

In the present invention, the thickness of the neodymium iron boron alloy cast sheet is preferably 0.28 to 0.4mm, for example, 0.3 mm.

In the invention, the components and the contents of the neodymium iron boron alloy cast sheet are consistent with those of the corresponding neodymium iron boron alloy powder except the content of the S element.

The operation and conditions of the jet milling treatment may be conventional in the art, and preferably, the particle size of the neodymium iron boron alloy powder after the jet milling treatment is within 3.9 to 4.2 μm, for example, 4.0 μm, and more preferably, 4.0 to 4.2 μm.

Wherein the oxygen content in the milling chamber of the jet mill in the jet milling treatment is preferably below 15 ppm.

The rotation speed of the sorting wheel in the jet mill treatment is preferably 3500-4300 rpm/min, such as 4000 rpm/min.

According to the invention, the thickness of the neodymium iron boron alloy cast piece and the operation and condition of the jet milling treatment are combined, so that the specific surface area of the neodymium iron boron alloy powder is reduced, and further the oxygen content in the finally obtained neodymium iron boron magnet material is reduced.

In the present invention, the molding operation and conditions may be those conventional in the art, and the molding is preferably performed by orientation molding in a magnetic field of 1.8T or more, and more preferably performed by orientation molding in a magnetic field of 1.8 to 2.5T.

In the present invention, the sintering temperature is preferably 1070 to 1090 ℃, for example 1070 ℃ or 1080 ℃.

In the present invention, the sintering temperature may be a temperature conventional in the art, and the sintering time is preferably 4 to 7 hours, for example 6 hours.

In the present invention, the operation conditions of the heat treatment can be conventional in the art, the temperature of the heat treatment is usually 460 to 520 ℃, for example 500 ℃, and the time of the heat treatment is usually 4 to 10 hours, for example 6 hours.

Experiments show that 0.1-0.5 wt% of elemental sulfur and/or sulfur oxide is added into neodymium iron boron alloy powder in a certain mode, the elemental sulfur and the rare earth element can chemically react in the sintering process, sulfides with extremely high gasification points can be formed in the intercrystalline region of the magnet, the existence of the sulfides improves the magnetic isolation effect of a crystal boundary, so that the coercivity can be effectively improved, and meanwhile, the cost is low, and large-scale production is expected to be carried out.

At present, the prior art always has the defect that the coercive force of the final magnet is reduced because crystal grains grow up when the sintering temperature is overhigh. The inventor of the invention finds that the temperature resistance of the magnet is improved by combining the sulfur element with the high-melting-point metal (such as Zr, Nb, Hf, Ti and the like) and other necessary conditions in the invention, so that sintered grains of the magnet cannot grow up at higher temperature, and the problem of coercive force reduction of the magnet caused by overhigh sintering temperature is solved while the compactness of the magnet is improved.

The invention also provides a neodymium iron boron magnet material which is prepared by adopting the preparation method.

The invention provides a neodymium iron boron magnet material which comprises the following components in percentage by mass:

R：29.5～31.5wt％；

Fe：64～68wt％；

B：0.85～0.92wt％；

S：0.095～0.5wt％；

n: 0.2-0.6 wt%, wherein the N comprises one or more of Zr, Nb, Hf and Ti, and the mass ratio of the N to the S is (1-4.1): 1;

and R is a rare earth element, and at least Nd is contained in R.

In the invention, the content of R is preferably 30.5 to 31 wt%, for example, 30.83 wt%, 30.84 wt%, 30.85 wt%, 30.86 wt% or 30.91 wt%, and the percentage is the percentage of the mass of each component in the total mass of the neodymium iron boron magnet material.

In the present invention, the R may further include a light rare earth element, such as Pr, which is conventional in the art.

In the present invention, the content of Nd is preferably 28 to 31 wt%, for example 28.44 wt%, 28.45 wt%, 28.46 wt%, 28.47 wt%, 29.44 wt%, 30.43 wt% or 30.91 wt%, more preferably 28 to 30 wt%, where the percentage is the percentage of the mass of each component in the total mass of the ndfeb magnet material.

In the present invention, the R may further include a heavy rare earth element that is conventional in the art, and the content of the heavy rare earth element is preferably less than 3.5 wt%, and more preferably 0.4 to 3.5 wt%, for example, 0.42 wt%, 1.41 wt%, 2.38 wt%, 2.39 wt%, 2.4 wt%, or 2.41 wt%, and more preferably 1.4 to 3 wt%, where the percentage is the percentage of the mass of each component in the total mass of the neodymium iron boron magnet material.

In the present invention, the heavy rare earth element preferably includes Dy and/or Tb, more preferably Dy and/or Tb.

In the present invention, the content of Fe is preferably 65 to 67 wt%, for example, 65.773 wt%, 65.875 wt%, 65.92 wt%, 65.962 wt%, 65.963 wt%, 65.964 wt%, 65.976 wt%, 65.989 wt%, 66.041 wt% or 66.136 wt%, where the percentage is the percentage of the mass of each component in the total mass of the ndfeb magnet material.

In the present invention, the content of B is preferably 0.9 to 0.92 wt%, for example, 0.92 wt%.

In the present invention, the content of S is preferably 0.095 to 0.445 wt%, for example, 0.098 wt%, 0.099 wt%, 0.101 wt%, 0.105 wt%, 0.204 wt%, 0.211 wt%, 0.355 wt%, or 0.443 wt%, the percentage being the mass of each component in the total mass of the neodymium iron boron magnet material.

In the present invention, S is preferably Nd₂S₃In the form of said neodymium-iron-boron magnet material, e.g. as Nd₂S₃The form of (A) is enriched in the intercrystalline trigones. The inter-grain triangular region refers to a void formed by three or more crystal grains.

Wherein, the Nd₂S₃The content of (b) is preferably 0.49 to 2.85 wt%, more preferably 0.52 to 2.65 wt%, such as 0.523 wt%, 2.087 wt% or 2.641 wt%, of the total mass of the ndfeb magnet material.

In the invention, through multiple experiments, the loss of the S content in the process of preparing the neodymium iron boron magnet material is usually not more than 0.02 wt%, and through repeated research, the loss is mainly found to be caused by the fact that the neodymium iron boron magnet contains a large amount of rare earth elements with extremely strong activity, the rare earth elements are extremely easy to react with S to generate vulcanized rare earth, and meanwhile, the neodymium iron boron alloy powder in the preparation process has extremely small particle size and extremely large specific surface area, so that the reaction activity of the S and the rare earth elements is higher.

In the present invention, the mass ratio of N to S may be, for example, 0.4: 0.098, 0.4:0.099, 0.4:0.101, 0.4:0.105, 0.4:0.107, 0.4:0.204, 0.3:0.211, 0.4:0.355 or 0.5:0.443, preferably (3-4.1): 1.

in the invention, the content of N is preferably 0.3 to 0.5 wt%, for example, 0.3 wt%, 0.4 wt% or 0.5 wt%, and the percentage is the percentage of the mass of each component in the total mass of the neodymium iron boron magnet material.

In the present invention, the kind of N is preferably one or more of Zr, Nb, Hf and Ti, for example Zr and/or Ti.

Wherein the Zr content is preferably 0.3 to 0.5 wt%, such as 0.3 wt%, 0.4 wt% or 0.5 wt%.

Wherein, the content of Ti is preferably 0.3 to 0.5 wt%, for example 0.3 wt%.

In the present invention, the neodymium iron boron magnet material may preferably further include Cu.

The content of Cu is preferably 0.05 to 0.15 wt%, for example 0.05 wt% or 0.1 wt%, and the percentage is the percentage of the mass of each component in the total mass of the neodymium iron boron magnet material.

In the present invention, the neodymium iron boron magnet material may preferably further include Co.

The content of Co is preferably 0.5 to 2 wt%, more preferably 0.5 to 1.5 wt%, for example 0.5 wt% or 1 wt%, and the percentage is the percentage of the mass of each component in the total mass of the neodymium iron boron magnet material.

In the present invention, the neodymium iron boron magnet material may preferably further include Ga.

The content of Ga is preferably 0.20 to 0.3 wt%, for example, 0.25 wt% or 0.3 wt%, and more preferably 0.22 to 0.28 wt%, where the percentage is the percentage of the mass of each component in the total mass of the ndfeb magnet material.

In the present invention, the neodymium iron boron magnet material may preferably further include Al.

The content of Al is preferably 0.2 to 0.4 wt%, such as 0.2 wt%, 0.25 wt% or 0.3 wt%, and more preferably 0.25 to 0.35 wt%, where the percentage is the percentage of the mass of each component in the total mass of the neodymium iron boron magnet material.

In the invention, the neodymium iron boron magnet material can also comprise O.

In the present invention, the content of O is preferably less than 0.12 wt%, for example, between 0.09 and 0.11 wt%, for example, 0.091 wt%, 0.092 wt%, 0.093 wt%, 0.095 wt%, 0.096 wt%, 0.098 wt%, 0.103 wt% or 0.108 wt%, and more preferably less than 0.1 wt%. In the present invention, the oxygen content is controlled at a lower level in a preferred embodiment, thereby preventing the reaction of oxygen with the rare earth element to form rare earth oxide, reducing the fluidity of the intergranular neodymium-rich phase, and reducing the coercive force.

In the invention, the neodymium iron boron magnet material preferably comprises the following components in percentage by mass: r: 29.5 to 31.5 wt%, Fe: 64-68 wt%, B: 0.85-0.92 wt%, Cu: 0.05 to 0.25 wt%, Co: 0.5 to 2 wt%, Ga: 0.2-0.3 wt%, Al: 0.2-0.4 wt%, S: 0.095 to 0.5 weight percent of oxygen and less than or equal to O0.12 wt%, N: 0.2-0.6 wt%, wherein the N comprises one or more of Zr, Nb, Hf and Ti, and the mass ratio of the N to the S is (1-4.1): 1; the rare earth element R is a rare earth element, the R comprises Nd and RH, the RH is a heavy rare earth element, the content of the heavy rare earth element is 0.4-3.5 wt%, and the content of the Nd is 28-31 wt%; the percentage is that the mass of each component accounts for the total mass of the neodymium iron boron magnet material; wherein the heavy rare earth element preferably includes Dy and/or Tb, and S is preferably Nd₂S₃Is present in the form of said Nd₂S₃The content of (B) is 0.49-2.85 wt% of the total mass of the neodymium iron boron magnet material.

In the invention, the neodymium iron boron magnet material preferably comprises the following components in percentage by mass: r: 30.5-31 wt%; fe: 65-67 wt%, B: 0.9-0.92 wt%, Cu: 0.05-0.15 wt%, Co: 0.5 to 1.5 wt%, Ga: 0.22-0.28 wt%, Al: 0.25 to 0.35 wt%, S: 0.095-0.45 wt%, O is less than or equal to 0.11 wt%, N: 0.3-0.5 wt%, wherein the N comprises Zr and/or Ti, and the mass ratio of the N to the S is (1-4.1): 1; the rare earth element R is a rare earth element, the R comprises Nd and RH, the RH is a heavy rare earth element, the content of the heavy rare earth element is 1.4-3 wt%, and the content of the Nd is 28-30 wt%; preferably, the heavy rare earth element preferably includes Dy and/or Tb, wherein S is Nd₂S₃Is present in the form of said Nd₂S₃The content of (a) is 0.52-2.65 wt% of the total mass of the neodymium iron boron magnet material, and the percentage is that the mass of each component accounts for the total mass of the neodymium iron boron magnet material.

In the invention, the neodymium iron boron magnet material preferably comprises the following components in percentage by mass: nd: 28.45 wt%, Dy: 2.41 wt%, Al: 0.3 wt%, Cu: 0.1 wt%, Co: 1 wt%, Ga: 0.25 wt%, Zr: 0.4 wt%, B: 0.92 wt%, Fe: 65.976 wt%, S: 0.098 wt%, O: 0.096 wt%, the percentage is the percentage of each component mass in the total mass of the neodymium iron boron magnet material.

In the invention, the neodymium iron boron magnet material preferably comprises the following components in percentage by mass: nd: 28.46 wt%, Dy: 2.38 wt%, Al: 0.3 wt%, Cu: 0.1 wt%, Co: 1 wt%, Ga: 0.25 wt%, Zr: 0.4 wt%, B: 0.92 wt%, Fe: 65.875 wt%, S: 0.204 wt%, O: 0.091 wt%, the percentage is the percentage of the mass of each component in the total mass of the neodymium iron boron magnet material.

In the invention, the neodymium iron boron magnet material preferably comprises the following components in percentage by mass: nd: 28.47 wt%, Dy: 2.39 wt%, Al: 0.3 wt%, Cu: 0.1 wt%, Co: 1 wt%, Ga: 0.25 wt%, Zr: 0.4 wt%, B: 0.92 wt%, Fe: 65.962 wt%, S: 0.105 wt%, O: 0.103 wt%; wherein, preferably, S is Nd₂S₃In the form of said Nd-Fe-B magnet material₂S₃The content of (a) is 0.523 wt%, and the percentage is that the mass of each component accounts for the total mass of the neodymium iron boron magnet material.

In the invention, the neodymium iron boron magnet material preferably comprises the following components in percentage by mass: nd: 28.44 wt%, Dy: 2.4 wt%, Al: 0.3 wt%, Cu: 0.1 wt%, Co: 1 wt%, Ga: 0.25 wt%, Ti: 0.3 wt%, B: 0.92 wt%, Fe: 65.964 wt%, S: 0.211 wt%, O: 0.095 wt%, the percentage is the percentage of each component mass in the total mass of the neodymium iron boron magnet material.

In the invention, the neodymium iron boron magnet material preferably comprises the following components in percentage by mass: nd: 28.45 wt%, Dy: 2.41 wt%, Al: 0.3 wt%, Cu: 0.1 wt%, Co: 1 wt%, Ga: 0.25 wt%, Zr: 0.4 wt%, B: 0.85 wt%, Fe: 66.041 wt%, S: 0.101 wt%, O: 0.098 wt%, the percentage is the percentage of each component mass in the total mass of the neodymium iron boron magnet material.

In the invention, the neodymium iron boron magnet material preferably comprises the following components in percentage by mass: nd: 29.44 wt%, Tb: 1.41 wt%, Al: 0.3 wt%, Cu: 0.1 wt%, Co: 1 wt%, Ga: 0.25 wt%, Zr: 0.4 wt%, B: 0.92 wt%, Fe: 65.963 wt%, S: 0.099 wt%, O: 0.108 wt% of the total mass of the neodymium iron boron magnet material.

In the invention, the neodymium iron boron magnet material preferably comprises the following components in percentage by mass: nd: 30.43 wt%, Tb: 0.42 wt%, Al: 0.3 wt%, Cu: 0.1 wt%, Co: 1 wt%, Ga: 0.25 wt%, Zr: 0.4 wt%, B: 0.92 wt%, Fe: 65.989 wt%, S: 0.099 wt%, O: 0.092 wt%, the percentage is the percentage of each component mass in the total mass of the neodymium iron boron magnet material.

In the invention, the neodymium iron boron magnet material preferably comprises the following components in percentage by mass: nd: 30.91 wt%, Al: 0.3 wt%, Cu: 0.1 wt%, Co: 1 wt%, Ga: 0.25 wt%, Zr: 0.4 wt%, B: 0.92 wt%, Fe: 65.92 wt%, S: 0.107 wt%, O: 0.093 wt%, the percentage is that the mass of each component accounts for the total mass of the neodymium iron boron magnet material.

In the invention, the neodymium iron boron magnet material preferably comprises the following components in percentage by mass: nd: 28.47 wt%, Dy: 2.38 wt%, Al: 0.25 wt%, Cu: 0.05 wt%, Co: 1 wt%, Ga: 0.3 wt%, Zr: 0.4 wt%, B: 0.92 wt%, Fe: 65.773 wt%, S: 0.355 wt%, O: 0.092 wt%; wherein, preferably, S is Nd₂S₃In the form of said Nd-Fe-B magnet material₂S₃The content of (B) is 2.087 wt%; the percentage is the percentage of the mass of each component in the total mass of the neodymium iron boron magnet material.

In the invention, the neodymium iron boron magnet material preferably comprises the following components in percentage by mass: nd: 28.44 wt%, Dy: 2.39 wt%, Al: 0.2 wt%, Cu: 0.1 wt%, Co: 0.5 wt%, Ga: 0.25 wt%, Zr: 0.5 wt%, B: 0.92 wt%, Fe: 66.136 wt%, S: 0.443 wt%, O: 0.091 wt%; wherein, preferably, S is Nd₂S₃In the form of said Nd-Fe-B magnet material₂S₃The content of (B) is 2.641 wt%; the percentage is the percentage of the mass of each component in the total mass of the neodymium iron boron magnet material.

In the present invention, one skilled in the art knows that Nd is neodymium, Fe is iron, B is boron, Tb is terbium, Co is cobalt, Cu is copper, Ga is gallium, Al is aluminum, Zr is zirconium, Ti is titanium, Nb is niobium, Hf is hafnium, S is sulfur, and O is oxygen.

In the invention, the percentage is the mass percentage of each component in the total mass of the neodymium iron boron magnet material.

The invention also provides application of the neodymium iron boron magnet material in a motor as an electronic element.

In the invention, the motor is preferably a new energy automobile driving motor, an air conditioner compressor or an industrial servo motor, a wind driven generator, an energy-saving elevator or a loudspeaker assembly.

On the basis of the common knowledge in the field, the above preferred conditions can be combined randomly to obtain the preferred embodiments of the invention.

The reagents and starting materials used in the present invention are commercially available.

The positive progress effects of the invention are as follows: the neodymium iron boron magnet material can still remarkably improve the coercive force and remanence of the neodymium iron boron magnet material under the condition of reducing the use of heavy rare earth elements even not adding the heavy rare earth elements, has low cost and is expected to be produced in a large scale. The remanence of the neodymium iron boron magnet material can be as high as 14.15kGs, and the coercive force can be as high as 31.3 kOe.

Drawings

Fig. 1 is an EPMA diagram of the neodymium iron boron magnet material of example 3.

Detailed Description

The invention is further illustrated by the following examples, which are not intended to limit the scope of the invention. The experimental methods without specifying specific conditions in the following examples were selected according to the conventional methods and conditions, or according to the commercial instructions.