阅读说明：本技术 一种稀土永磁材料、原料组合物、制备方法、应用、电机 (rare earth permanent magnet material, raw material composition, preparation method, application and motor ) 是由 廖宗博 骆溁 蓝琴 黄佳莹 于 2019-09-03 设计创作，主要内容包括：本发明公开了一种稀土永磁材料、原料组合物、制备方法、应用、电机。以重量百分比计,该稀土永磁材料包括下述组分：R 28.5-33.0wt％；RH＞1.5wt％；Cu 0-0.08wt％,但不为0wt％；Co 0.5-2.0wt％；Ga 0.05-0.30wt％；B 0.95-1.05wt％；余量为Fe及不可避免的杂质。本发明中的R-T-B系永磁材料性能优异,在永磁材料中重稀土元素含量为3.0-4.5wt％的条件下,Br≥12.78kGs,Hcj≥29.55kOe；在永磁材料中重稀土元素含量为1.5-2.5wt％的条件下,Br≥13.06kGs,Hcj≥26.31kOe。(The invention discloses a rare earth permanent magnet material, a raw material composition, a preparation method, application and a motor. The rare earth permanent magnetic material comprises the following components in percentage by weight: r28.5-33.0 wt%; RH > 1.5 wt%; cu 0-0.08 wt%, but not 0 wt%; 0.5-2.0 wt% of Co; ga0.05-0.30 wt%; b0.95-1.05 wt%; the balance being Fe and unavoidable impurities. The R-T-B series permanent magnet material has excellent performance, Br is more than or equal to 12.78kGs, and Hcj is more than or equal to 29.55kOe under the condition that the content of heavy rare earth elements in the permanent magnet material is 3.0-4.5 wt%; under the condition that the content of heavy rare earth elements in the permanent magnet material is 1.5-2.5 wt%, Br is more than or equal to 13.06kGs, and Hcj is more than or equal to 26.31 kOe.)

1. an R-T-B series permanent magnetic material is characterized by comprising the following components in percentage by weight: r: 28.5-33.0 wt%; RH: more than 1.5 wt%; cu: 0 to 0.08 wt% but not 0 wt%; co: 0.5-2.0 wt%; ga: 0.05-0.30 wt%; b: 0.95-1.05 wt%; the balance of Fe and inevitable impurities; wherein: the R is a rare earth element and at least comprises Nd and RH; the RH is heavy rare earth element.

2. the R-T-B series permanent magnetic material according to claim 1, wherein the R-T-B series permanent magnetic material comprises R₂T₁₄B crystal grains and R₂T₁₄B grain boundary phase between crystal grains, the composition of the grain boundary phase is R_x-(B_1-a-b-c-Ga_a-Cu_b-T_c)_yWherein: t is Fe and Co, 2b<a<3.5b，1/2c<a+b，50at％<x<65at％，35at％<y<50 at%, at% refers to the atomic percentage of each element in the grain boundary phase; wherein:

Said x is preferably from 55 to 60 at%, such as 55.6 at%, 56.7 at%, 56.9 at%, 57 at%, 58.6 at%, 59 at%, 59.1 at% or 59.5 at%, at% referring to the atomic percentage of R in said grain boundary phase;

Said y is preferably 40 to 45 at%, such as 40.5 at%, 40.9 at%, 41 at%, 41.4 at%, 43 at%, 43.1 at%, 43.3 at% or 44.4 at%, at% referring to the atomic percentage of "B, Ga, Cu, Fe and Co" in said grain boundary phase;

the a is preferably 0.23-0.24, such as 0.23, 0.235 or 0.24, and the a refers to the atomic ratio of the Ga in the elements of B, Ga, Cu, Fe and Co;

B is preferably 0.1-0.115, such as 0.1, 0.103, 0.11 or 0.115, and B refers to the atomic ratio of the Cu in the elements of B, Ga, Cu, Fe and Co;

c is preferably 0.64-0.65, such as 0.64, 0.644 or 0.65, and c refers to the atomic ratio of the Fe and Co in the B, Ga, Cu, Fe and Co elements;

Preferably, said R is_x-(B_1-a-b-c-Ga_a-Cu_b-T_c)_yIs R_55.6-(B_0.01-Ga_0.235-Cu_0.115-T_0.64)_44.4、R_56.9-(B_0.02-Ga_0.23-Cu_0.11-T_0.64)_43.1、R₅₉-(B_0.02-Ga_0.24-Cu_0.1-T_0.64)₄₁、R_59.1-(B_0.02-Ga_0.23-Cu_0.11-T_0.64)_40.9、R_56.7-(B_0.02-Ga_0.23-Cu_0.1-T_0.65)_43.3、R₅₇-(B_0.02-Ga_0.23-Cu_0.1-T_0.65)₄₃、R_58.6-(B_0.02-Ga_0.23-Cu_0.11-T_0.64)_41.4Or R_59.5-(B_0.023-Ga_0.23-Cu_0.103-T_0.644)_40.5。

3. The R-T-B based permanent magnetic material according to claim 1 or 2, wherein R further comprises Pr;

and/or, the RH is Dy and/or Tb, preferably Tb;

And/or the content of R is 28.5-32.0 wt% or 30.5-33.0 wt%, preferably 28.94 wt%, 30.53 wt%, 30.66 wt%, 31.09 wt%, 31.83 wt%, 31.92 wt%, 32.23 wt% or 32.86 wt%, and the percentage refers to the weight percentage in the R-T-B series permanent magnetic material;

And/or the Nd content is 24.4-30.5 wt%, preferably 24.4-28.0 wt% or 28.0-30.5 wt%, such as 24.46 wt%, 26.4 wt%, 27.39 wt%, 27.94 wt%, 28.36 wt%, 29.58 wt%, 30.24 wt% or 30.36 wt%, percentage referring to the weight percentage in the R-T-B based permanent magnetic material;

and/or the RH is present in an amount of 1.5-4.5 wt%, preferably 1.5-2.5 wt% or 3.0-4.5 wt%, such as 1.99 wt%, 2.25 wt%, 2.5 wt%, 2.3 wt%, 3.7 wt%, 3.98 wt%, 4.13 wt% or 4.48 wt%, percentage referring to the weight percentage in the R-T-B based permanent magnetic material;

And/or, when Tb is included in the RH, the Tb content is 1.5-4.5 wt%, such as 1.99 wt%, 2.01 wt%, 2.25 wt%, 2.3 wt%, 2.99 wt%, 3.19 wt%, 3.61 wt%, or 3.98 wt%;

And/or, when Dy is included in the RH, the Dy content is 0.45-1.0 wt%; for example 0.5 wt%, 0.52 wt%, 0.51 wt%, 0.99 wt% or 0.49 wt%; the percentage refers to the weight percentage in the R-T-B series permanent magnetic material;

And/or the Cu content is 0.01-0.08 wt%, 0.04-0.08 wt% or 0.05-0.08 wt%, preferably 0.01 wt%, 0.05 wt%, 0.06 wt%, 0.07 wt% or 0.08 wt%, and the percentage refers to the weight percentage in the R-T-B series permanent magnetic material;

And/or the Co content is 0.78-2.0 wt%, preferably 1.0-2.0 wt%, such as 0.79 wt%, 0.99 wt%, 1 wt%, 1.39 wt%, 1.58 wt%, 1.6 wt% or 2 wt%, the percentages referring to the weight percentage in the R-T-B series permanent magnetic material;

And/or the content of Ga is 0.05 or 0.1-0.3 wt%, preferably 0.1 wt%, 0.2 wt% or 0.3 wt%, and the percentage refers to the weight percentage in the R-T-B series permanent magnetic material;

And/or the content of B is 0.95-1.04 wt%, preferably 0.95 wt%, 0.98 wt%, 0.99 wt% or 1.04 wt%, and the percentage refers to the weight percentage in the R-T-B series permanent magnetic material.

4. The R-T-B series permanent magnetic material according to claim 3, wherein in the R-T-B series permanent magnetic material, the R-T-B series permanent magnetic material comprises the following components: r28.5-32.0 wt%; RH 3.0-4.5 wt%; cu 0-0.08 wt%, but not 0 wt%; 1.0-2.0 wt% of Co; ga0.05-0.30 wt%; b0.95-1.05 wt%; the balance of Fe and inevitable impurities; the percentage refers to the weight percentage in the R-T-B series permanent magnetic material;

or, the R-T-B series permanent magnetic material comprises the following components: r28.5-32.0 wt%; RH 3.2-4.5 wt%; cu 0.04-0.08 wt%; 1.0-2.0 wt% of Co; ga 0.10-0.30 wt%; b0.95-1.0 wt%; the balance being Fe and unavoidable impurities, the percentages being percentages by weight in the R-T-B series permanent magnetic material;

Or, the R-T-B series permanent magnetic material comprises the following components: nd 24.4-28.0 wt%; tb 3.0-4.0 wt%; 0.5 to 1.0 weight percent of Dy; cu 0.01-0.08 wt%; 1.0-2.0 wt% of Co; ga0.05-0.30 wt%; b0.95-1.05 wt%; the balance being Fe and unavoidable impurities, the percentages being percentages by weight in the R-T-B series permanent magnetic material;

Or, the R-T-B series permanent magnetic material comprises the following components: r is 30.5 to 33.0 weight percent; RH > 1.5 wt%; cu 0-0.08 wt%, but not 0 wt%; 0.78-2.0 wt% of Co; ga0.05-0.30 wt%; b0.95-1.05 wt%; the balance being Fe and unavoidable impurities, the percentages being percentages by weight in the R-T-B series permanent magnetic material;

Or, the R-T-B series permanent magnetic material comprises the following components: r is 30.5 to 33.0 weight percent; RH 1.5-2.5 wt%; cu 0.04-0.08 wt%; 0.78-1.6 wt% of Co; ga 0.10-0.30 wt%; b0.95-1.0 wt%; the balance being Fe and unavoidable impurities, the percentages being percentages by weight in the R-T-B series permanent magnetic material;

Or, the R-T-B series permanent magnetic material comprises the following components: 28.0-30.5 wt% of Nd; tb 1.5-2.5 wt%; 0-0.5 wt% of Dy; cu 0.01-0.08 wt%; 0.78-2.0 wt% of Co; ga0.05-0.30 wt%; b0.95-1.05 wt%; the balance being Fe and unavoidable impurities, the percentages being percentages by weight in the R-T-B-based permanent magnet material.

5. An R-T-B series permanent magnetic material, characterized in that the R-T-B series permanent magnetic material comprises R₂T₁₄B crystal grains and R₂T₁₄B grain boundary phase between crystal grains, the composition of the grain boundary phase is R_x-(B_1-a-b-c-Ga_a-Cu_b-T_c)_yWherein: t is Fe and Co, 2b<a<3.5b，1/2c<a+b，50at％<x<65at％，35at％<y<50 at%, at% refers to the atomic percentage of each element in the grain boundary phase; the R is a rare earth element and at least comprises Nd and RH; the RH is a heavy rare earth element; wherein:

X is the same as x in claim 2;

Y is the same as y in claim 2;

a is the same as a in claim 2;

b is the same as that described in claim 2;

C is the same as c described in claim 2;

The kind of R is the same as that of R described in claim 1 or 3;

The RH is the same as the RH described in claim 1 or 3.

6. A raw material composition of an R-T-B series permanent magnetic material is characterized by comprising the following components in percentage by weight: r: 28.5-32.5 wt%; RH: more than 1.2 wt%; cu: 0 to 0.08 wt% but not 0 wt%; co: 0.5-2.0 wt%; ga: 0.05-0.30 wt%; b: 0.95-1.05 wt%; the balance of Fe and inevitable impurities; wherein: the R is a rare earth element and at least comprises Nd and RH; the RH is heavy rare earth element.

7. The raw material composition of R-T-B series permanent magnetic material according to claim 6, wherein said R further comprises Pr;

And/or, the RH is Dy and/or Tb, preferably Tb;

and/or the content of R is 28.5-31.5 wt%, 30.5-32.5 wt% or 30.0-32.5 wt%, preferably 28.5 wt%, 30.1 wt%, 30.5 wt%, 30.7 wt%, 31.5 wt%, 31.8 wt% or 32.5 wt%, and the percentage refers to the weight percentage in the raw material composition of the R-T-B series permanent magnetic material;

And/or, the Nd content is 24.5-30.5 wt%, preferably 24.5-28.0 wt% or 28.0-30.5 wt%, such as 24.5 wt%, 26.5 wt%, 27.5 wt%, 28.0 wt%, 28.5 wt%, 29.7 wt%, 30.3 wt% or 30.5 wt%, percentage referring to the weight percentage in the raw material composition of the R-T-B system permanent magnetic material;

and/or the RH is 1.2-4.5 wt%, preferably 1.5-2.0 wt% or 3.0-4.5 wt%, more preferably 1.5 wt%, 1.8 wt%, 2.0 wt%, 3.2 wt%, 3.5 wt%, 3.6 wt% or 4.0 wt%, the percentage refers to the weight percentage in the raw material composition of the R-T-B series permanent magnetic material;

And/or, when Tb is included in the RH, the content of Tb is 1.2-4.5 wt%, preferably 1.5 wt%, 1.8 wt%, 2 wt%, 3 wt%, 3.2 wt%, 3.6 wt% or 4 wt%, and the percentage refers to the weight percentage in the raw material composition of the R-T-B series permanent magnetic material;

And/or, when Dy is included in the RH, the Dy content is 0-0.5 wt%, preferably 0.5 wt%;

and/or the Cu content is 0.01-0.08 wt%, 0.04-0.08 wt% or 0.05-0.08 wt%, preferably 0.01 wt%, 0.04 wt%, 0.06 wt% or 0.08 wt%, and the percentage refers to the weight percentage in the raw material composition of the R-T-B series permanent magnetic material;

And/or the content of Co is 0.8-2.0 wt%, preferably 1.0-2.0 wt%, more preferably 0.8 wt%, 1.0 wt%, 1.4 wt%, 1.6 wt% or 2.0 wt%, and the percentage refers to the weight percentage in the raw material composition of the R-T-B series permanent magnetic material;

And/or the content of Ga is 0.05 or 0.1-0.3 wt%, preferably 0.1 wt%, 0.2 wt% or 0.3 wt%, and the percentage refers to the weight percentage in the raw material composition of the R-T-B series permanent magnetic material;

And/or the content of B is 0.95-1.0 or 1.05 wt%, preferably 0.95 wt%, 0.98 wt% or 1.0 wt%, and the percentage refers to the weight percentage in the raw material composition of the R-T-B series permanent magnetic material;

Or the raw material composition of the R-T-B series permanent magnetic material comprises the following components: r28.5-31.5 wt%; RH 3.0-4.5 wt%; cu 0-0.08 wt%, but not 0 wt%; 1.0-2.0 wt% of Co; ga0.05-0.30 wt%; b0.95-1.05 wt%; the balance of Fe and inevitable impurities; the percentage refers to the weight percentage in the raw material composition of the R-T-B series permanent magnetic material;

Or the raw material composition of the R-T-B series permanent magnetic material comprises the following components: r28.5-31.5 wt%, RH 3.2-4.5 wt%, Cu 0.04-0.08 wt%, Co 1.0-2.0 wt%, Ga 0.10-0.30 wt% and B0.95-1.0 wt%; the balance being Fe and unavoidable impurities, the percentages being percentages by weight in the raw material composition of the R-T-B-based permanent magnetic material;

or the raw material composition of the R-T-B series permanent magnetic material comprises the following components: 24.5 to 28.0 weight percent of Nd, 3.0 to 4.0 weight percent of Tb, 0 to 0.5 weight percent of Dy, 0.01 to 0.08 weight percent of Cu, 1.0 to 2.0 weight percent of Co, 0.05 to 0.30 weight percent of Ga and 0.95 to 1.05 weight percent of B; the balance being Fe and unavoidable impurities, the percentages being percentages by weight in the raw material composition of the R-T-B-based permanent magnetic material;

Or the raw material composition of the R-T-B series permanent magnetic material comprises the following components: r is 30.5-32.5 wt%; RH > 1.2 wt%; cu 0-0.08 wt%, but not 0 wt%; 0.8-2.0 wt% of Co; ga0.05-0.30 wt%; b0.95-1.05 wt%; the balance being Fe and unavoidable impurities, the percentages being percentages by weight in the raw material composition of the R-T-B-based permanent magnetic material;

or the raw material composition of the R-T-B series permanent magnetic material comprises the following components: 30.5 to 32.5 weight percent of R, 1.5 to 2.0 weight percent of RH, 0.04 to 0.08 weight percent of Cu, 0.8 to 1.6 weight percent of Co, 0.10 to 0.30 weight percent of Ga and 0.95 to 1.0 weight percent of B; the balance being Fe and unavoidable impurities, the percentages being percentages by weight in the raw material composition of the R-T-B-based permanent magnetic material;

Or the raw material composition of the R-T-B series permanent magnetic material comprises the following components: 28.5 to 30.5 weight percent of Nd, 1.5 to 2.0 weight percent of Tb, 0 to 0.5 weight percent of Dy, 0.01 to 0.08 weight percent of Cu, 0.8 to 2.0 weight percent of Co, 0.05 to 0.30 weight percent of Ga and 0.95 to 1.05 weight percent of B; the balance being Fe and unavoidable impurities, the percentages being percentages by weight in the raw material composition of the R-T-B-based permanent magnet material.

8. A preparation method of an R-T-B series permanent magnetic material is characterized by comprising the following steps: the R-T-B series permanent magnet material is obtained by casting, crushing, forming, sintering and grain boundary diffusion treatment of the melt of the raw material composition of the R-T-B series permanent magnet material according to claim 6 or 7; wherein: the sintering is carried out according to the following steps in sequence: sintering in a first section, sintering in a second section and cooling; the temperature of the first-stage sintering is less than or equal to 1040 ℃; the second-stage sintering is heating sintering based on the first-stage sintering, the temperature difference is more than or equal to 5-10 ℃, the heating speed is more than or equal to 5 ℃/min, and the time of the second-stage sintering is less than or equal to 1 h; the cooling speed is more than or equal to 7 ℃/min, and the cooling end point is less than or equal to 100 ℃;

Preferably, the melt of the raw material composition of the R-T-B series permanent magnetic material is prepared by the following method: smelting in a high-frequency vacuum induction smelting furnace; the degree of vacuum of the melting furnace is preferably 5 × 10^-2Pa; the smelting temperature is preferably below 1500 ℃;

Preferably, the casting process is carried out according to the following steps: in Ar atmosphere, at 10%²DEG C/sec-10⁴Cooling at the speed of DEG C/second;

Preferably, the crushing process is carried out as follows: performing hydrogen absorption, dehydrogenation and cooling treatment; the hydrogen absorption is preferably carried out under the condition that the hydrogen pressure is 0.15 MPa; the pulverization is preferably carried out by a jet mill, the pressure of a pulverization chamber of the jet mill pulverization is preferably 0.38MPa, and the pulverization time of the jet mill is preferably 3 hours;

preferably, the forming method is a magnetic field forming method or a hot-pressing hot-deformation method;

Preferably, before the first-stage sintering, preheating treatment is also carried out, wherein the preheating temperature is preferably 300-600 ℃; the preheating time is preferably 1-2 h; preferably, the preheating is sequentially carried out at the temperature of 300 ℃ and the temperature of 600 ℃ for 1 hour respectively;

the temperature of the first stage sintering is preferably 1000-1030 ℃, for example 1030 ℃;

the time of the first sintering stage is preferably more than or equal to 2 hours, such as 3 hours;

Preferably, in the second-stage sintering, the temperature difference is more than or equal to 5-10 ℃ and less than or equal to 20 ℃, such as 10 ℃;

the time of the second-stage sintering is preferably 1 h;

In the sintering process, the cooling speed is preferably 10 ℃/min;

In the sintering process, the cooling end point is preferably 100 ℃;

Before cooling, Ar gas can be introduced to ensure that the air pressure reaches 0.1 MPa;

Preferably, the grain boundary diffusion treatment is performed by the following steps: evaporating, coating or sputtering a substance containing Dy or Tb on the surface of the R-T-B series permanent magnet material, and performing diffusion heat treatment; the temperature of the diffusion heat treatment is preferably 850-980 ℃, and the time of the diffusion heat treatment is preferably 12-48 h;

preferably, after the grain boundary diffusion treatment, a heat treatment is further performed, the temperature of the heat treatment is preferably 500 ℃, the time of the heat treatment is preferably 3 hours, and the environment of the heat treatment is preferably 9 x 10^-3vacuum condition of Pa.

9. the R-T-B series permanent magnetic material prepared by the preparation method of the R-T-B series permanent magnetic material according to claim 8.

10. use of the R-T-B series permanent magnetic material according to any one of claims 1 to 5 and 9 as an electronic component in a motor;

the application is preferably the application as an electronic component in a motor with the rotating speed of 3000-7000rpm and/or the working temperature of 80-180 ℃, or the application as an electronic component in a high-rotating-speed motor and/or a household appliance.

11. An electrical machine comprising the R-T-B based permanent magnetic material according to any one of claims 1 to 5 and 9.

Technical Field

The invention relates to a rare earth permanent magnet material, a raw material composition, a preparation method, application and a motor.

background

R-T-B series rare earth permanent magnetic materials are widely applied to modern industry and electronic technology, such as electronic computers, automatic control systems, motors and generators, nuclear magnetic resonance imaging instruments, acoustic devices, material edge separation devices, communication equipment and other fields. With the development of new application fields and the rigor and changeful application conditions, products with high coercivity are more and more in demand.

at present, the intrinsic coercive force (Hcj) of the magnet can be generally improved by adding high-melting-point metal (generally, metal with a melting point higher than 1538 ℃) in the raw material formula of the R-T-B series rare earth permanent magnet material, for example, adding elements such as Nb, Zr, Ti, Cr, V, W and Mo. The addition of the high-melting-point metal elements can play a role in pinning a grain boundary and refining grains, and further realize the improvement of the Hcj of the magnet, but the addition of the high-melting-point metal elements has more requirements on a sintering process, so that the sintering difficulty is increased, the process cost is improved, and the residual magnetization (Br) of the magnet is lower.

Research also shows that if low-melting-point metal is directly adopted for sintering, intercrystalline compounds (abnormal growth of crystal grains) which are not beneficial to magnetic performance can be generated, and sintering compactness (poor sintering) can be caused by the problem of a sintering process, so that Br of the permanent magnet material is lower.

it can be seen that in the existing low-melting-point metal formula, Br and Hcj in the permanent magnet material magnet are difficult to be synchronously maintained at a high level. Therefore, how to obtain the R-T-B rare earth permanent magnetic material with high Hcj and high Br is a technical problem to be solved in the field.

Disclosure of Invention

the invention aims to overcome the defect that Br and Hcj of an R-T-B series rare earth permanent magnet material are difficult to realize synchronous promotion in the prior art, and provides a rare earth permanent magnet material, a raw material composition, a preparation method, application and a motor. The R-T-B series permanent magnetic material has excellent performance, and the content of heavy rare earth elements is 3.0-4.5 wt%Br is more than or equal to 12.78kGs, Hcj is more than or equal to 29.55 kOe; under the condition that the content of the heavy rare earth elements is 1.5-2.5 wt%, Br is more than or equal to 13.06kGs, Hcj is more than or equal to 26.31 kOe; the synchronous promotion of Br and Hcj can be realized. Compared with the conventional formula, the formula of the R-T-B series permanent magnet material does not add high-melting-point metal, only uses a small amount of low-melting-point metal, and reduces the influence of the magnet on Br as much as possible while improving the Hcj of the magnet. In addition, the preparation of the R-T-B series permanent magnetic material realizes low-temperature sintering, and reduces energy consumption; by designing the formula components and the process, R is formed at the grain boundary_x-(B_1-a-b-c-Ga_a-Cu_b-T_c)_yThe crystal phase improves the appearance of the crystal boundary, forms a continuous crystal boundary channel and further improves the performance of the magnet.

the invention provides an R-T-B series permanent magnetic material which comprises the following components in percentage by weight:

R：28.5-33.0wt％；

RH：＞1.5wt％；

cu: 0 to 0.08 wt% but not 0 wt%;

Co：0.5-2.0wt％；

Ga：0.05-0.30wt％；

B：0.95-1.05wt％；

The balance of Fe and inevitable impurities; wherein:

The R is a rare earth element and at least comprises Nd and RH; the RH is heavy rare earth element.

In the present invention, it is preferable that the R-T-B based permanent magnetic material does not contain a high melting point metal element. Wherein, the high melting point metal element generally refers to a metal element with a melting point higher than 1538 ℃, such as one or more of Ti, V, Zr, Nb, Cr, W and Mo.

in the present invention, preferably, the R-T-B series permanent magnetic material comprises R₂T₁₄B crystal grains and R₂T₁₄B grain boundary phase between crystal grains, the composition of the grain boundary phase is R_x-(B_1-a-b-c-Ga_a-Cu_b-T_c)_ywherein: t is Fe and Co, 2b<a<3.5b，1/2c<a+b，50at％<x<65at％，35at％<y<50 at%, which is the atomic percentage of each element in the grain boundary phase.

The inventor finds that R in the development process_x-(B_1-a-b-c-Ga_a-Cu_b-T_c)_ythe formation of the grain boundary phase can increase the wettability of the grain boundary, improve the appearance of the grain boundary and provide a continuous grain boundary channel for the diffusion process, thereby improving Hcj and obtaining the permanent magnet material with high Br and high Hcj.

Furthermore, the inventors have also found that R_x-(B_1-a-b-c-Ga_a-Cu_b-T_c)_yThe grain boundary phase has balanced R and T components, has excellent mutual dissolution effect with the Nd-rich phase and the B-rich phase at the grain boundary, reduces the agglomeration of the grain boundary phase, forms a uniformly distributed grain boundary layer, achieves good demagnetizing coupling effect, and can further improve the Hcj of the magnet.

In the grain boundary phase, x is preferably 55 to 60 at%, for example, 55.6 at%, 56.7 at%, 56.9 at%, 57 at%, 58.6 at%, 59 at%, 59.1 at%, or 59.5 at%, where at% is an atomic percentage of R in the grain boundary phase.

wherein, in the grain boundary phase, y is preferably 40 to 45 at%, for example, 40.5 at%, 40.9 at%, 41 at%, 41.4 at%, 43 at%, 43.1 at%, 43.3 at%, or 44.4 at%, and at% means the atomic percentage of "B, Ga, Cu, Fe, and Co" in the grain boundary phase.

In the grain boundary phase, a is preferably 0.23 to 0.24, for example, 0.23, 0.235 or 0.24, and a is an atomic ratio of Ga in the elements "B, Ga, Cu, Fe and Co".

In the grain boundary phase, B is preferably 0.1-0.115, such as 0.1, 0.103, 0.11 or 0.115, and B is an atomic ratio of Cu in "B, Ga, Cu, Fe and Co" elements.

Wherein, in the grain boundary phase, c is preferably 0.64-0.65, such as 0.64, 0.644 or 0.65, and c refers to the atomic ratio of the Fe and Co in the B, Ga, Cu, Fe and Co elements.

wherein, preferably, R is_x-(B_1-a-b-c-Ga_a-Cu_b-T_c)_yIs R_55.6-(B_0.01-Ga_0.235-Cu_0.115-T_0.64)_44.4、R_56.9-(B_0.02-Ga_0.23-Cu_0.11-T_0.64)_43.1、R₅₉-(B_0.02-Ga_0.24-Cu_0.1-T_0.64)₄₁、R_59.1-(B_0.02-Ga_0.23-Cu_0.11-T_0.64)_40.9、R_56.7-(B_0.02-Ga_0.23-Cu_0.1-T_0.65)_43.3、R₅₇-(B_0.02-Ga_0.23-Cu_0.1-T_0.65)₄₃、R_58.6-(B_0.02-Ga_0.23-Cu_0.11-T_0.64)_41.4Or R_59.5-(B_0.023-Ga_0.23-Cu_0.103-T_0.644)_40.5。

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

In the present invention, the RH may be a heavy rare earth element conventional in the art, such as Dy and/or Tb, preferably Tb.

In the present invention, the content of R is preferably 28.5 to 32.0 wt% or 30.5 to 33.0 wt%, for example 28.94 wt%, 30.53 wt%, 30.66 wt%, 31.09 wt%, 31.83 wt%, 31.92 wt%, 32.23 wt% or 32.86 wt%, which is a weight percentage in the R-T-B based permanent magnetic material.

in the present invention, the content of Nd is preferably 24.4 to 30.5 wt%, such as 24.4 to 28.0 wt% or 28.0 to 30.5 wt%, and further such as 24.46 wt%, 26.4 wt%, 27.39 wt%, 27.94 wt%, 28.36 wt%, 29.58 wt%, 30.24 wt%, or 30.36 wt%, the percentage referring to the weight percentage in the R-T-B based permanent magnetic material.

In the present invention, the content of the RH is preferably 1.5 to 4.5 wt%, more preferably 1.5 to 2.5 wt% or 3.0 to 4.5 wt%, for example, 1.99 wt%, 2.25 wt%, 2.3 wt%, 2.5 wt%, 3.7 wt%, 3.98 wt%, 4.13 wt% or 4.48 wt%, which is a weight percentage in the R-T-B based permanent magnetic material.

When Tb is included in the RH, it is preferable that the Tb content is 1.5 to 4.5 wt%, for example, 1.99 wt%, 2.01 wt%, 2.25 wt%, 2.3 wt%, 2.99 wt%, 3.19 wt%, 3.61 wt%, or 3.98 wt%.

When Dy is included in the RH, preferably, the Dy is contained in an amount of 0.45 to 1.0 wt%; for example 0.5 wt%, 0.52 wt%, 0.51 wt%, 0.99 wt% or 0.49 wt%; the percentage refers to the weight percentage in the R-T-B series permanent magnet material.

In the present invention, the content of Cu is preferably 0.01 to 0.08 wt%, 0.04 to 0.08 wt%, or 0.05 to 0.08 wt%, for example, 0.01 wt%, 0.05 wt%, 0.06 wt%, 0.07 wt%, or 0.08 wt%, which is a weight percentage in the R-T-B-based permanent magnetic material.

In the present invention, the content of Co is preferably 0.78 to 2.0 wt%, for example 1.0 to 2.0 wt%, further for example 0.79 wt%, 0.99 wt%, 1 wt%, 1.39 wt%, 1.58 wt%, 1.6 wt% or 2 wt%, the percentage referring to the weight percentage in the R-T-B based permanent magnetic material.

In the present invention, the content of Ga is preferably 0.05 or 0.1-0.3 wt%, for example 0.1 wt%, 0.2 wt% or 0.3 wt%, which is the weight percentage in the R-T-B based permanent magnetic material.

In the present invention, the content of B is preferably 0.95 to 1.04 wt%, for example 0.95 wt%, 0.98 wt%, 0.99 wt% or 1.04 wt%, which is a weight percentage in the R-T-B based permanent magnetic material.

in the invention, preferably, the R-T-B series permanent magnetic material comprises the following components: r28.5-32.0 wt%; RH 3.0-4.5 wt%; cu 0-0.08 wt%, but not 0 wt%; 1.0-2.0 wt% of Co; ga0.05-0.30 wt%; b0.95-1.05 wt%; the balance of Fe and inevitable impurities; the percentage refers to the weight percentage in the R-T-B series permanent magnet material.

In the invention, preferably, the R-T-B series permanent magnetic material comprises the following components: r28.5-32.0 wt%; RH 3.2-4.5 wt%; cu 0.04-0.08 wt%; 1.0-2.0 wt% of Co; ga 0.10-0.30 wt%; b0.95-1.0 wt%; the balance being Fe and unavoidable impurities, the percentages being percentages by weight in the R-T-B-based permanent magnet material.

In the invention, preferably, the R-T-B series permanent magnetic material comprises the following components: nd 24.4-28.0 wt%; tb 3.0-4.0 wt%; 0.5 to 1.0 weight percent of Dy; cu 0.01-0.08 wt%; 1.0-2.0 wt% of Co; ga0.05-0.30 wt%; b0.95-1.05 wt%; the balance being Fe and unavoidable impurities, the percentages being percentages by weight in the R-T-B-based permanent magnet material.

in a preferred embodiment of the present invention, the R-T-B series permanent magnetic material comprises the following components: nd 24.46 wt%, Tb 3.98 wt%, Dy 0.50 wt%, Cu 0.07 wt%, Co 2.00 wt%, Ga 0.30 wt%, and B0.95wt%, and the balance Fe and inevitable impurities, the percentages being percentages by weight in the R-T-B permanent magnetic material.

In a preferred embodiment of the present invention, the R-T-B series permanent magnetic material comprises the following components: 26.40 wt% of Nd, 3.61 wt% of Tb, 0.52 wt% of Dy, 0.06 wt% of Cu, 1.58 wt% of Co, 0.20 wt% of Ga, and 0.98wt% of B0, and the balance being Fe and inevitable impurities, the percentages being percentages by weight in the R-T-B permanent magnet material.

In a preferred embodiment of the present invention, the R-T-B series permanent magnetic material comprises the following components: nd 27.39 wt%, Tb 3.19 wt%, Dy 0.51 wt%, Cu 0.05 wt%, Co 1.39 wt%, Ga 0.10 wt%, and B0.99wt%, and the balance Fe and inevitable impurities, wherein the percentages refer to the weight percentage of the R-T-B permanent magnet material.

in a preferred embodiment of the present invention, the R-T-B series permanent magnetic material comprises the following components: nd 27.94 wt%, Tb 2.99 wt%, Dy 0.99 wt%, Cu 0.01 wt%, Co 1.00 wt%, Ga0.05 wt% and B1.04wt%, the balance being Fe and inevitable impurities, the percentages being percentages by weight in the R-T-B permanent magnet material.

In the invention, preferably, the R-T-B series permanent magnetic material comprises the following components: r is 30.5 to 33.0 weight percent; RH > 1.5 wt%; cu 0-0.08 wt%, but not 0 wt%; 0.78-2.0 wt% of Co; ga0.05-0.30 wt%; b0.95-1.05 wt%; the balance being Fe and unavoidable impurities, the percentages being percentages by weight in the R-T-B-based permanent magnet material.

In the invention, preferably, the R-T-B series permanent magnetic material comprises the following components: r is 30.5 to 33.0 weight percent; RH 1.5-2.5 wt%; cu 0.04-0.08 wt%; 0.78-1.6 wt% of Co; ga 0.10-0.30 wt%; b0.95-1.0 wt%; the balance being Fe and unavoidable impurities, the percentages being percentages by weight in the R-T-B-based permanent magnet material.

In the invention, preferably, the R-T-B series permanent magnetic material comprises the following components: 28.0-30.5 wt% of Nd; tb 1.5-2.5 wt%; 0-0.5 wt% of Dy; cu 0.01-0.08 wt%; 0.78-2.0 wt% of Co; ga0.05-0.30 wt%; b0.95-1.05 wt%; the balance being Fe and unavoidable impurities, the percentages being percentages by weight in the R-T-B-based permanent magnet material.

In a preferred embodiment of the present invention, the R-T-B series permanent magnetic material comprises the following components: 28.36 wt% of Nd, 2.30 wt% of Tb, 0.08 wt% of Cu, 2.00 wt% of Co, 0.30 wt% of Ga, and 0.95 wt% of B, and the balance being Fe and inevitable impurities, the percentages being percentages by weight in the R-T-B-based permanent magnet material.

in a preferred embodiment of the present invention, the R-T-B series permanent magnetic material comprises the following components: nd 29.58 wt%, Tb 2.25 wt%, Cu 0.06 wt%, Co 1.60 wt%, Ga 0.20 wt% and B0.98 wt%, the balance being Fe and unavoidable impurities, the percentages being percentages by weight in the R-T-B permanent magnet material.

In a preferred embodiment of the present invention, the R-T-B series permanent magnetic material comprises the following components: 30.24 wt% of Nd, 1.99 wt% of Tb, 0.05 wt% of Cu, 0.99 wt% of Co, 0.10 wt% of Ga, and 0.99 wt% of B, and the balance being Fe and inevitable impurities, the percentages being percentages by weight in the R-T-B-based permanent magnet material.

In a preferred embodiment of the present invention, the R-T-B series permanent magnetic material comprises the following components: 30.36 wt% of Nd, 2.01 wt% of Tb, 0.49 wt% of Dy, 0.01 wt% of Cu, 0.79 wt% of Co, 0.05 wt% of Ga, and 1.04wt% of B, and the balance of Fe and inevitable impurities, wherein the percentages refer to the weight percentage of the R-T-B permanent magnet material.

The inventionAlso provides an R-T-B series permanent magnetic material, which comprises R₂T₁₄b crystal grains and R₂T₁₄B grain boundary phase between crystal grains, the composition of the grain boundary phase is R_x-(B_1-a-b-c-Ga_a-Cu_b-T_c)_ywherein: t is Fe and Co, 2b<a<3.5b，1/2c<a+b，50at％<x<65at％，35at％<y<50 at%, at% refers to the atomic percentage of each element in the grain boundary phase;

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

wherein x, y, a, b, and c are as described above.

Wherein, preferably, R is_x-(B_1-a-b-c-Ga_a-Cu_b-T_c)_yis R_55.6-(B_0.01-Ga_0.235-Cu_0.115-T_0.64)_44.4、R_56.9-(B_0.02-Ga_0.23-Cu_0.11-T_0.64)_43.1、R₅₉-(B_0.02-Ga_0.24-Cu_0.1-T_0.64)₄₁、R_59.1-(B_0.02-Ga_0.23-Cu_0.11-T_0.64)_40.9、R_56.7-(B_0.02-Ga_0.23-Cu_0.1-T_0.65)_43.3、R₅₇-(B_0.02-Ga_0.23-Cu_0.1-T_0.65)₄₃、R_58.6-(B_0.02-Ga_0.23-Cu_0.11-T_0.64)_41.4Or R_59.5-(B_0.023-Ga_0.23-Cu_0.103-T_0.644)_40.5。

Preferably, the R-T-B series permanent magnetic material comprises the following components in percentage by weight: r: 28.5-33.0 wt%; RH: more than 1.5 wt%; cu: 0 to 0.08 wt% but not 0 wt%; co: 0.5-2.0 wt%; ga: 0.05-0.30 wt%; b: 0.95-1.05 wt%; the balance of Fe and inevitable impurities; the R is a rare earth element and at least comprises Nd and RH; the RH is heavy rare earth element.

The contents of R, RH, Cu, Co, Ga, B and Nd are as described above.

The invention also provides a raw material composition of the R-T-B series permanent magnetic material, which comprises the following components in percentage by weight:

R：28.5-32.5wt％；

RH：＞1.2wt％；

Cu: 0 to 0.08 wt% but not 0 wt%;

Co：0.5-2.0wt％；

Ga：0.05-0.30wt％；

B：0.95-1.05wt％；

The balance of Fe and inevitable impurities; wherein:

The R is a rare earth element and at least comprises Nd and RH; the RH is heavy rare earth element.

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

In the present invention, the RH may be a heavy rare earth element conventional in the art, such as Dy and/or Tb, preferably Tb.

In the present invention, the content of R is preferably 28.5 to 31.5 wt%, 30.5 to 32.5 wt%, or 30.0 to 32.5 wt%, for example 28.5 wt%, 30.1 wt%, 30.5 wt%, 30.7 wt%, 31.5 wt%, 31.8 wt%, or 32.5 wt%, which is a weight percentage in the raw material composition of the R-T-B-based permanent magnetic material.

In the permanent magnet material, if the R content is lower than 28.5 wt%, a sufficient rare earth-rich phase cannot be obtained, the requirement on a sintering process is high, sintering difficulty may be caused, and the performance of the permanent magnet material is reduced; if the R content is higher than 32.5 wt%, the rare earth content is high, but higher Br is difficult to realize, so that rare earth resources are wasted.

In the present invention, the content of Nd is preferably 24.5 to 30.5 wt%, for example 24.5 to 28.0 wt% or 28.0 to 30.5 wt%, and further, for example, 24.5 wt%, 26.5 wt%, 27.5 wt%, 28.0 wt%, 28.5 wt%, 29.7 wt%, 30.3 wt%, or 30.5 wt%, which is a weight percentage in the raw material composition of the R-T-B-based permanent magnetic material.

In the present invention, the RH content is preferably 1.2 to 4.5 wt%, more preferably 1.2 to 2.0 wt% or 3.0 to 4.5 wt%, for example, 1.5 wt%, 1.8 wt%, 2.0 wt%, 3.2 wt%, 3.5 wt%, 3.6 wt% or 4.0 wt%, and the percentage means the weight percentage in the raw material composition of the R-T-B-based permanent magnetic material.

When Tb is included in the RH, it is preferable that the Tb content is 1.2 to 4.5 wt%, for example, 1.5 wt%, 1.8 wt%, 2 wt%, 3 wt%, 3.2 wt%, 3.6 wt%, or 4 wt%, which refers to the weight percentage in the raw material composition of the R-T-B based permanent magnetic material.

When Dy is included in the RH, it is preferably contained in an amount of 0 to 0.5 wt%, for example, 0.5 wt%.

when Tb and Dy are included in the RH, it is preferable that: the Tb accounts for 1.2-3.0 wt% and the Dy accounts for 0-0.5 wt%, such as Tb 3.0 wt% and Dy 0.5 wt%, or Tb 1.5 wt% and Dy 0.5 wt%; the percentage refers to the weight percentage in the raw material composition of the R-T-B series permanent magnet material.

in the present invention, the content of Cu is preferably 0.01 to 0.08 wt%, 0.04 to 0.08 wt%, or 0.05 to 0.08 wt%, for example, 0.01 wt%, 0.04 wt%, 0.06 wt%, or 0.08 wt%, which is a weight percentage in the raw material composition of the R-T-B system permanent magnetic material.

In the permanent magnetic material of the present invention, if Cu is not contained, R cannot be formed_x-(B_1-a-b-c-Ga_a-Cu_b-T_c)_yPhase, a high Hcj permanent magnetic material cannot be obtained; if the Cu content is higher than 0.08 wt%, the volume fraction of the main phase may be affected, and a permanent magnet material with high Br cannot be obtained.

In the present invention, the content of Co is preferably 0.8 to 2.0 wt%, for example 1.0 to 2.0 wt%, further for example 0.8 wt%, 1.0 wt%, 1.4 wt%, 1.6 wt% or 2.0 wt%, which is a weight percentage in the raw material composition of the R-T-B-based permanent magnetic material.

In the present invention, the content of Ga is preferably 0.05 or 0.1 to 0.3 wt%, for example 0.1 wt%, 0.2 wt% or 0.3 wt%, which is a weight percentage in the raw material composition of the R-T-B based permanent magnetic material.

in the permanent magnetic material of the present invention, R is present if the Ga content is less than 0.05 wt%_x-(B_1-a-b-c-Ga_a-Cu_b-T_c)_yA grain boundary phase cannot be effectively formed, and a permanent magnet material with high Hcj cannot be obtained; if the Ga content is higher than 0.3 wt%, the volume fraction of the main phase may be affected, and a permanent magnet material with high Br cannot be obtained.

In the present invention, the content of B is preferably 0.95 to 1.0 or 1.05 wt%, for example, 0.95 wt%, 0.98 wt% or 1.0 wt%, which is a weight percentage in the raw material composition of the R-T-B-based permanent magnetic material.

In the permanent magnetic material, the content of B is closely related to the volume fraction of the main phase, and R can be influenced_x-(B_1-a-b-c-Ga_a-Cu_b-T_c)_yAnd (4) forming a grain boundary phase. If the B content is less than 0.95 wt%, R may be formed₂T₁₇Phase, and the main phase volume fraction decreases, a permanent magnetic material with high Hcj and high Br cannot be obtained. If the B content is more than 1.05 wt%, too much B-rich phase is generated, and the performance of the permanent magnet material is lowered.

In the invention, preferably, the raw material composition of the R-T-B series permanent magnetic material comprises the following components: r28.5-31.5 wt%; RH 3.0-4.5 wt%; cu 0-0.08 wt%, but not 0 wt%; 1.0-2.0 wt% of Co; ga0.05-0.30 wt%; b0.95-1.05 wt%; the balance of Fe and inevitable impurities; the percentage refers to the weight percentage in the raw material composition of the R-T-B series permanent magnet material.

In the invention, preferably, the raw material composition of the R-T-B series permanent magnetic material comprises the following components: r28.5-31.5 wt%, RH 3.2-4.5 wt%, Cu 0.04-0.08 wt%, Co 1.0-2.0 wt%, Ga 0.10-0.30 wt% and B0.95-1.0 wt%; the balance being Fe and unavoidable impurities, the percentages being percentages by weight in the raw material composition of the R-T-B-based permanent magnet material.

In the invention, preferably, the raw material composition of the R-T-B series permanent magnetic material comprises the following components: 24.5 to 28.0 weight percent of Nd, 3.0 to 4.0 weight percent of Tb, 0 to 0.5 weight percent of Dy, 0.01 to 0.08 weight percent of Cu, 1.0 to 2.0 weight percent of Co, 0.05 to 0.30 weight percent of Ga0.95 to 1.05 weight percent of B; the balance being Fe and unavoidable impurities, the percentages being percentages by weight in the raw material composition of the R-T-B-based permanent magnet material.

In a preferred embodiment of the present invention, the raw material composition of the R-T-B series permanent magnetic material comprises the following components: nd 24.5 wt%, Tb 4 wt%, Cu 0.08 wt%, Co 2 wt%, Ga 0.3 wt%, and B0.95 wt%, with the balance being Fe and unavoidable impurities, the percentages being percentages by weight in the raw material composition of the R-T-B-based permanent magnetic material.

In a preferred embodiment of the present invention, the raw material composition of the R-T-B series permanent magnetic material comprises the following components: nd 26.5 wt%, Tb 3.6 wt%, Cu 0.06 wt%, Co 1.6 wt%, Ga 0.2 wt%, and B0.98 wt%, with the balance being Fe and unavoidable impurities, the percentages being by weight in the raw material composition of the R-T-B-based permanent magnetic material.

in a preferred embodiment of the present invention, the raw material composition of the R-T-B series permanent magnetic material comprises the following components: nd 27.5 wt%, Tb 3.2 wt%, Cu 0.04 wt%, Co 1.4 wt%, Ga 0.1 wt%, and B1 wt%, with the balance being Fe and unavoidable impurities, the percentages being percentages by weight in the raw material composition of the R-T-B-based permanent magnetic material.

In a preferred embodiment of the present invention, the raw material composition of the R-T-B series permanent magnetic material comprises the following components: 28 wt% of Nd, 3 wt% of Tb, 0.5 wt% of Dy, 0.01 wt% of Cu, 1 wt% of Co, 0.05 wt% of Ga, and 1.05wt% of B, and the balance of Fe and inevitable impurities, wherein the percentages refer to the weight percentage in the raw material composition of the R-T-B permanent magnet material.

in the invention, preferably, the raw material composition of the R-T-B series permanent magnetic material comprises the following components: r is 30.5-32.5 wt%; RH > 1.2 wt%; cu 0-0.08 wt%, but not 0 wt%; 0.8-2.0 wt% of Co; ga0.05-0.30 wt%; b0.95-1.05 wt%; the balance being Fe and unavoidable impurities, the percentages being percentages by weight in the raw material composition of the R-T-B-based permanent magnet material.

In the invention, preferably, the raw material composition of the R-T-B series permanent magnetic material comprises the following components: 30.5 to 32.5 weight percent of R, 1.2 to 2.0 weight percent of RH, 0.04 to 0.08 weight percent of Cu, 0.8 to 1.6 weight percent of Co, 0.10 to 0.30 weight percent of Ga and 0.95 to 1.0 weight percent of B; the balance being Fe and unavoidable impurities, the percentages being percentages by weight in the raw material composition of the R-T-B-based permanent magnet material.

In the invention, preferably, the raw material composition of the R-T-B series permanent magnetic material comprises the following components: 28.5 to 30.5 weight percent of Nd, 1.2 to 2.0 weight percent of Tb, 0 to 0.5 weight percent of Dy, 0.01 to 0.08 weight percent of Cu, 0.8 to 2.0 weight percent of Co, 0.05 to 0.30 weight percent of Ga0.95 to 1.05 weight percent of B; the balance being Fe and unavoidable impurities, the percentages being percentages by weight in the raw material composition of the R-T-B-based permanent magnet material.

In a preferred embodiment of the present invention, the raw material composition of the R-T-B series permanent magnetic material comprises the following components: nd 28.5 wt%, Tb 2.0 wt%, Cu 0.08 wt%, Co 2.0 wt%, Ga 0.3 wt%, and B0.95 wt%, with the balance being Fe and unavoidable impurities, the percentages being by weight in the raw material composition of the R-T-B-based permanent magnetic material.

in a preferred embodiment of the present invention, the raw material composition of the R-T-B series permanent magnetic material comprises the following components: nd 29.7 wt%, Tb 1.8 wt%, Cu 0.06 wt%, Co 1.6 wt%, Ga 0.2 wt%, and B0.98 wt%, with the balance being Fe and unavoidable impurities, the percentages being by weight in the raw material composition of the R-T-B-based permanent magnetic material.

In a preferred embodiment of the present invention, the raw material composition of the R-T-B series permanent magnetic material comprises the following components: 30.3 wt% of Nd, 1.5 wt% of Tb, 0.04 wt% of Cu, 1 wt% of Co, 0.1 wt% of Ga, and 1.0 wt% of B, and the balance being Fe and unavoidable impurities, the percentages being percentages by weight in the raw material composition of the R-T-B-based permanent magnet material.

In a preferred embodiment of the present invention, the raw material composition of the R-T-B series permanent magnetic material comprises the following components: 30.5 wt% of Nd, 1.5 wt% of Tb, 0.5 wt% of Dy, 0.01 wt% of Cu, 0.8 wt% of Co, 0.05 wt% of Ga, and 1.05 wt% of B, and the balance of Fe and inevitable impurities, wherein the percentages refer to the weight percentage of the raw material composition of the R-T-B permanent magnet material.

the invention also provides a preparation method of the R-T-B series permanent magnetic material, which comprises the following steps: casting, crushing, forming, sintering and grain boundary diffusion treatment are carried out on the molten liquid of the raw material composition of the R-T-B series permanent magnetic material to obtain the R-T-B series permanent magnetic material; wherein:

The sintering is carried out according to the following steps in sequence: sintering in a first section, sintering in a second section and cooling;

The temperature of the first-stage sintering is less than or equal to 1040 ℃;

The second-stage sintering is heating sintering based on the first-stage sintering, the temperature difference is more than or equal to 5-10 ℃, the heating speed is more than or equal to 5 ℃/min, and the time of the second-stage sintering is less than or equal to 1 h;

The cooling speed is more than or equal to 7 ℃/min, and the cooling end point is less than or equal to 100 ℃.

in the present invention, the melt of the raw material composition of the R-T-B series permanent magnetic material can be prepared by a conventional method in the art, for example: smelting in a high-frequency vacuum induction smelting furnace. The vacuum degree of the smelting furnace can be 5 multiplied by 10^-2Pa. The temperature of the smelting can be below 1500 ℃.

In the present invention, the casting process may be a casting process conventional in the art, for example: in an Ar gas atmosphere (e.g. 5.5X 10)⁴Pa of Ar gas atmosphere) at 10 deg.f²DEG C/sec-10⁴Cooling at a rate of DEG C/sec.

In the present invention, the crushing process may be a crushing process conventional in the art, for example, by hydrogen absorption, dehydrogenation, and cooling.

Wherein the hydrogen absorption can be carried out under the condition that the hydrogen pressure is 0.15 MPa.

Wherein the dehydrogenation is carried out under a condition of raising the temperature while evacuating.

in the present invention, the pulverization process may be a pulverization process conventional in the art, such as jet milling.

Wherein the jet mill pulverization is carried out in a nitrogen atmosphere having an oxidizing gas content of 150ppm or less. The oxidizing gas refers to oxygen or moisture content.

Wherein, the pressure of the crushing chamber for crushing by the jet mill can be 0.38 MPa.

Wherein, the jet mill pulverization time can be 3 hours.

Wherein after said pulverization, a lubricant, such as zinc stearate, may be added as is conventional in the art. The lubricant may be added in an amount of 0.10 to 0.15%, for example 0.12% by weight of the mixed powder.

in the present invention, the forming process may be a forming process conventional in the art, such as magnetic field forming or hot press hot deformation.

In the present invention, the sintering may be carried out under vacuum conditions, for example at 5X 10^-3Pa under vacuum.

In the present invention, the first stage may be preheated by conventional means in the art before sintering. The temperature of the preheating may be 300-600 ℃. The preheating time can be 1-2 h. Preferably, the preheating is carried out for 1 hour at the temperature of 300 ℃ and the temperature of 600 ℃ respectively in sequence.

in the present invention, the temperature of the first stage sintering is preferably 1000 to 1030 ℃, for example 1030 ℃.

In the present invention, the time for the first stage sintering is preferably ≧ 2h, for example, 3 h.

In the present invention, preferably, in the second stage sintering, the temperature difference is not less than 5-10 ℃ and not more than 20 ℃, for example, 10 ℃.

In the present invention, the time for the second stage sintering is preferably 1 hour.

in the present invention, in the sintering process, the cooling rate is preferably 10 ℃/min.

In the present invention, in the sintering process, the end point of the cooling is preferably 100 ℃.

The inventor finds that a small amount of margin B is dispersed and distributed at a grain boundary when the first-stage sintering is carried out, so that a grain boundary phase R can be promoted_x-(B_1-a-b-c-Ga_a-Cu_b-T_c)_yIs performed. The combination of the two-stage sintering process and the rapid cooling process can improve the compactness of the main phase, and meanwhile, the rapid change of the temperature provides pressure for the grain boundary, so that the grain boundary phase can be uniformly spread and distributed, and the effect of realizing the optimal tissue morphology by using a small amount of the grain boundary phase is achieved.

the inventor also finds that if only the first-stage sintering process is used, the compactness of the magnet is insufficient, the ideal effect of the grain boundary phase morphology cannot be achieved, and the permanent magnet material with high Br and high Hcj cannot be obtained. If only the second stage sintering process is used, abnormal growth of crystal grains may be caused, resulting in deterioration of magnet properties.

In the invention, Ar gas can be introduced before cooling to make the air pressure reach 0.1 MPa.

In the present invention, the grain boundary diffusion treatment may be performed by a conventional process in the art, for example, by depositing, coating, or sputtering a Dy or Tb-containing substance on the surface of the R-T-B-based permanent magnetic material, and performing diffusion heat treatment.

The Dy-containing substance may be Dy metal, a Dy-containing compound (e.g., Dy fluoride), or a Dy-containing alloy.

Wherein the Tb containing substance can be Tb metal, Tb containing compounds (such as Tb fluoride) or Tb containing alloys.

Wherein the temperature of the diffusion heat treatment may be 850-980 ℃, for example 850 ℃.

Wherein, the time of the diffusion heat treatment can be 12-48h, such as 24 h.

Wherein, after the grain boundary diffusion treatment, heat treatment can be carried out. The temperature of the heat treatment may be 500 ℃. The time of the heat treatment may be 3 hours. The environment of the heat treatment may be 9 × 10^-3Vacuum condition of Pa.

The invention also provides the R-T-B series permanent magnetic material prepared by the method.

The invention also provides application of the R-T-B series permanent magnetic material as an electronic component in a motor.

The application is preferably the application as an electronic component in a motor with the rotating speed of 3000-7000rpm and/or the working temperature of 80-180 ℃, for example, the application as an electronic component in a high-rotating-speed motor and/or a household appliance.

The invention also provides a motor which comprises the R-T-B series permanent magnet material.

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:

(1) The R-T-B series permanent magnet material has excellent performance, Br is more than or equal to 12.78kGs, and Hcj is more than or equal to 29.55kOe under the condition that the content of heavy rare earth elements in the permanent magnet material is 3.0-4.5 wt%; under the condition that the content of heavy rare earth elements in the permanent magnet material is 1.5-2.5 wt%, Br is more than or equal to 13.06kGs, Hcj is more than or equal to 26.31 kOe; the synchronous promotion of Br and Hcj can be realized.

(2) The preparation of the R-T-B series permanent magnetic material realizes low-temperature sintering, reduces energy consumption, and forms R at the grain boundary after sintering and cooling_x-(B_1-a-b-c-Ga_a-Cu_b-T_c)_yThe crystal phase improves the appearance of the crystal boundary, forms a continuous crystal boundary channel and further improves the performance of the magnet.

(3) Tb is added into the magnet, so that the magnet can be guaranteed to have an excellent temperature coefficient, and in the Dy diffusion process, part of Tb enters a crystal boundary from a main phase, so that reduction of Br can be avoided as far as possible while Hcj is improved.

Drawings

FIG. 1 shows R formed at grain boundaries by Nd, B, Ga, Co, Cu and the like in the magnet obtained in example 2_x-(B_1-a-b-c-Ga_a-Cu_b-T_c)_yAn intercrystalline phase.

FIG. 2 is a view showing the magnet obtained in example 2, wherein the position indicated by numeral 1 is used as an analysis point for detecting the grain boundary phase component.

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.