CN111243812A

CN111243812A - R-T-B series permanent magnetic material and preparation method and application thereof

Info

Publication number: CN111243812A
Application number: CN202010134700.5A
Authority: CN
Inventors: 付刚; 黄吉祥; 黄佳莹; 陈大崑; 黄清芳
Original assignee: Xiamen Tungsten Co Ltd; Fujian Changting Jinlong Rare Earth Co Ltd
Current assignee: Fujian Jinlong Rare Earth Co ltd
Priority date: 2020-02-29
Filing date: 2020-02-29
Publication date: 2020-06-05
Anticipated expiration: 2040-02-29
Also published as: WO2021169906A1; CN111243812B

Abstract

The invention discloses an R-T-B series permanent magnetic material and a preparation method and application thereof. The raw material composition of the R-T-B series permanent magnet material comprises the following components in percentage by mass: r: 28.5 to 33.0 percent; ga: more than 0.5 percent; cu: not less than 0.4%; b: 0.84-0.94%; al: 0.05-0.07%; co: less than or equal to 2.5 percent but not 0; fe: 60-70%; n: one or more of Ti, Zr and Nb; when N contains Ti, the content of Ti is 0.15-0.25%; when N contains Zr, the content of Zr is 0.2-0.35%; when the N contains Nb, the content of Nb is 0.2-0.5%; the percentage is the mass percentage of each component in the total mass of the raw material composition. The R-T-B series permanent magnetic material has better magnetic property, and the magnetic property of the same batch of products is uniform.

Description

R-T-B series permanent magnetic material and preparation method and application thereof

Technical Field

The invention relates to an R-T-B series permanent magnetic material and a preparation method and application thereof.

Background

Because of its excellent magnetic properties, R-T-B sintered magnets (R refers to rare earth elements, T refers to transition metal elements and group iii metal elements, and B refers to boron elements) are widely used in the fields of electronic products, automobiles, wind power, household appliances, elevators, industrial robots, and the like, for example, as energy sources in permanent magnet motors such as hard disks, mobile phones, earphones, elevator traction machines, generators, and the like, and the demand for the performance of magnets, such as remanence and coercive force, is increasing.

In order to increase the remanence of R-T-B-based sintered magnets, it is generally necessary to decrease the B content. However, when the content of B is at a low level, R is formed₂T₁₇And (4) phase(s). And R is₂T₁₇Has no room temperature uniaxial anisotropy, thereby deteriorating the performance of the magnet.

In the prior art, heavy rare earth elements such as Dy, Tb, Gd and the like are generally added to improve the coercive force of the material and improve the temperature coefficient, but the heavy rare earth is high in price, and the method for improving the coercive force of the R-T-B sintered magnet product can increase the raw material cost and is not beneficial to the application of the R-T-B sintered magnet.

Therefore, how to prepare the R-T-B magnet with high coercivity and high remanence by adopting a low B system (B < 5.88 at%) under the condition of not adding or adding a small amount of heavy rare earth is a technical problem to be solved in the field.

Disclosure of Invention

The invention aims to overcome the defect of poor magnet performance when B is less than 5.88 at% in the prior art, and provides an R-T-B series permanent magnet material and a preparation method and application thereof. The invention discovers for the first time that in the prior art, the coercive force of an R-T-B series magnet product of a low B system is improved in a small test, but the magnet still has the defect of nonuniform performance in industrial production, such as the prior Chinese patent CN 110619984A. In order to make the R-T-B series magnet product suitable for large-scale industrial production, the inventor finds that the R-T-B series permanent magnet material with excellent and uniform performance can be prepared by controlling the content of Al and properly matching Ga and Cu in a certain range with other elements.

In order to achieve the purpose, the invention provides the following technical scheme:

one of the technical schemes provided by the invention is as follows:

a raw material composition of an R-T-B series permanent magnet material comprises the following components in percentage by mass:

r: 28.5 to 33.0 wt%; r is a rare earth element at least containing Nd;

Ga：＞0.5wt％；

Cu：≥0.4wt％；

B：0.84～0.94wt％；

Al：0.05～0.07wt％；

co: less than or equal to 2.5 wt% but not 0;

Fe：62～70wt％；

n: one or more of Ti, Zr and Nb;

when N contains Ti, the content of Ti is 0.15-0.25 wt%;

when N contains Zr, the content of Zr is 0.2-0.35 wt%;

when the N contains Nb, the content of Nb is 0.2-0.5 wt%;

the percentage is the mass percentage of each component in the total mass of the raw material composition.

In the present invention, in the raw material composition, the content of R is preferably 29.5 to 32.5 wt%, for example, 29.5 wt%, 30 wt%, 30.5 wt%, 31 wt%, 32 wt%, more preferably 30.5 to 32 wt%, and the percentage is a mass percentage based on the total mass of the raw material composition.

Wherein, in the raw material composition, the content of Nd is preferably 21 to 25 wt%, such as 21.375 wt%, 21.5 wt%, 22.125 wt%, 22.5 wt%, 22.875 wt%, 23.25 wt%, 23.75 wt%, 24 wt%, 24.75 wt%, and more preferably 22 to 24 wt%; the percentage is the mass percentage of the total mass of the raw material composition.

In the invention, in the raw material composition, the R may further include Pr.

Wherein, when Pr is included in the R, the Pr content may be < 0.2 at% or > 8 at%; at% is the atomic percentage in the feedstock composition.

Wherein, when the R includes Pr, the content of Pr is preferably 5to 10 wt%, more preferably 7 to 9 wt%, such as 7.125 wt%, 7.375 wt%, 7.5 wt%, 7.625 wt%, 7.75 wt%, 8 wt%, 8.25 wt%; the percentage is the mass percentage of the total mass of the raw material composition.

In the present invention, the raw material composition may not contain heavy rare earth elements, and may also achieve a level of magnetic properties comparable to or even better than those of the prior art magnet materials. Alternatively, the raw material composition may further include RH, which is a heavy rare earth element.

When the raw material composition contains RH, the content of RH is preferably 1.5 to 6 wt%, more preferably 1 to 2.5 wt%, and the percentage is the mass percentage of the total mass of the raw material composition.

Wherein, the RH preferably includes one or more of Dy, Tb and Ho.

When the RH includes Dy, the content of Dy is preferably 1 to 2.5 wt%, for example, 2 wt%, in terms of mass percentage based on the total mass of the raw material composition.

When the RH includes Tb, the content of Tb is preferably 1 to 2.5 wt%, for example 2 wt%, and the percentage is the mass percentage of the total mass of the raw material composition.

In the present invention, the content of B in the raw material composition is preferably 0.85 to 0.94 wt%, for example, 0.9 wt%, 0.915 wt%, 0.92 wt%, 0.94 wt%, more preferably 0.915 to 0.94 wt%, and the percentage is the mass percentage of the total mass of the raw material composition.

In the present invention, in the raw material composition, the atomic percentage of R and the atomic percentage of B preferably satisfy the following relationship: B/R is not less than 0.38, wherein B is the atomic percent of B in the raw material composition, and R is the atomic percent of R in the raw material composition.

In the present invention, in the raw material composition, when the R further includes Pr, it is preferable that the B and the Nd satisfy the following relational expression: B/(Pr + Nd) ≥ 0.405, wherein B refers to the atomic percentage of B in the raw material composition, Pr refers to the atomic percentage of Pr in the raw material composition, and Nd refers to the atomic percentage of Nd in the raw material composition.

In the present invention, the content of Ga in the raw material composition is preferably 0.55 to 1.5 wt%, for example, 0.55 wt%, 0.6 wt%, 0.65 wt%, 0.75 wt%, 0.85 wt%, 0.95 wt%, 1.05 wt%, 1.15 wt%, 1.25 wt%, more preferably 1.05 to 1.5 wt%, with the percentage being mass% based on the total mass of the raw material composition.

In the present invention, the atomic ratio of the Ga to the B in the raw material composition preferably satisfies the following conditions Ga > 7.2941-1.24B (at%), and Ga 0.55 wt% to Ga < 1.05 wt%.

In the present invention, the content of Cu in the raw material composition is preferably 0.45 to 1 wt%, for example, 0.45 wt%, 0.5 wt%, 0.55 wt%, 0.6 wt%, 0.65 wt%, 0.7 wt%, 0.8 wt%, 0.9 wt%, more preferably 0.65 to 0.9 wt%, with the percentage being mass% based on the total mass of the raw material composition.

In the present invention, the content of Al in the raw material composition is preferably 0.06 to 0.07 wt%, for example, 0.06 wt%, 0.07 wt%, and more preferably 0.06 wt%; the percentage is the mass percentage of the total mass of the raw material composition.

In the present invention, the content of Co in the raw material composition is preferably 0.5 to 2.5 wt%, for example, 0.5 wt%, 1.00 wt%, 1.5 wt%, 2 wt%, 2.5 wt%, more preferably 1.00 to 2 wt%, and the percentage is a mass percentage based on the total mass of the raw material composition.

In the present invention, the content of Fe in the raw material composition is preferably 64 to 69 wt%, for example, 64.13 wt%, 64.265 wt%, 64.59 wt%, 64.78 wt%, 65.08 wt%, 65.12 wt%, 65.26 wt%, 65.35 wt%, 65.39 wt%, 65.85 wt%, 66.11 wt%, 66.135 wt%, 66.415 wt%, 67.29 wt%, 67.63 wt%, which is a mass percentage based on the total mass of the raw material composition.

In the present invention, when the N includes Ti in the raw material composition, the content of Ti is preferably 0.2 to 0.25 wt%, for example, 0.2 wt%, 0.25 wt%, and the percentage is a mass percentage based on the total mass of the raw material composition.

In the present invention, when the N includes Zr in the raw material composition, the Zr content is preferably 0.25 to 0.35 wt%, for example, 0.25 wt%, 0.26 wt%, 0.30 wt%, 0.35 wt%, and the percentage is a mass percentage based on the total mass of the raw material composition.

In the present invention, when the N contains Zr in the raw material composition, the Zr content is preferably 0.26 wt% or more and Zr < (3.48B-2.67) wt%, where B means a mass percentage of the B to the total mass of the raw material composition.

In the present invention, when the N includes Nb, the content of Nb in the raw material composition is preferably 0.2 to 0.3 wt%, for example, 0.2 wt% or 0.3 wt%, and the percentage is a mass percentage based on the total mass of the raw material composition.

In the present invention, when the N includes Ti and Nb in the raw material composition, the atomic percentage of Ti or Nb is preferably not less than 0.55 at%.

In the invention, the raw material composition of the R-T-B series permanent magnetic material preferably comprises the following components in percentage by mass:

r: 29.5 to 32.5 wt%; r is a rare earth element at least containing Nd;

Ga：0.55～1.5wt％；

Cu：0.45～1wt％；

B：0.85～0.94wt％；

Al：0.06～0.07wt％；

Co：0.5～2.5wt％；

Fe：64～69wt％；

n: one or more of Ti, Zr and Nb;

when N contains Ti, the content of Ti is 0.2-0.25 wt%;

when N contains Zr, the content of Zr is 0.25-0.35 wt%;

when the N contains Nb, the content of Nb is 0.2-0.3 wt%;

r: 29.5 to 32.5 wt%; r is a rare earth element comprising Nd and Pr;

Pr：5～10wt％；

Ga：0.55～1.5wt％；

Cu：0.45～1wt％；

B：0.85～0.94wt％；

Al：0.06～0.07wt％；

Co：0.5～2.5wt％；

Fe：64～69wt％；

n: one or more of Ti, Zr and Nb;

when N contains Ti, the content of Ti is 0.2-0.25 wt%;

when N contains Zr, the content of Zr is 0.25-0.35 wt%;

when the N contains Nb, the content of Nb is 0.2-0.3 wt%;

r: 29.5 to 32.5 wt%; r is a rare earth element comprising Nd and Pr;

Ga：0.55～1.5wt％；

Cu：0.45～1wt％；

B：0.85～0.94wt％；

Al：0.06～0.07wt％；

Co：0.5～2.5wt％；

Fe：64～69wt％；

Ti：0.2～0.25wt％；

r: 29.5 to 32.5 wt%; r is a rare earth element at least containing Nd;

Ga：0.55～1.5wt％；

Cu：0.45～1wt％；

B：0.85～0.94wt％；

Al：0.06～0.07wt％；

Co：0.5～2.5wt％；

Fe：64～69wt％；

Zr：0.25～0.35wt％；

r: 29.5 to 32.5 wt%; r is a rare earth element at least containing Nd;

Ga：0.55～1.5wt％；

Cu：0.45～1wt％；

B：0.85～0.94wt％；

Al：0.06～0.07wt％；

Co：0.5～2.5wt％；

Fe：64～69wt％；

Nb：0.2～0.3wt％；

In a preferred embodiment of the present invention, the raw material composition of the R-T-B series permanent magnetic material preferably includes the following components by mass: nd 21.375 wt%; pr 7.125 wt%; ga 0.55 wt%; 0.4 wt% of Cu; 0.05 wt% of Al; 0.5 wt% of Co; 0.15 wt% of Ti; b0.84 wt%; fe 69.01 wt%; the percentage is the mass percentage of each component in the total mass of the raw material composition.

In a preferred embodiment of the present invention, the raw material composition of the R-T-B series permanent magnetic material preferably includes the following components by mass: nd 22.125 wt%; pr 7.375 wt%; ga 0.6 wt%; 0.45 wt% of Cu; 0.06 wt% of Al; 1 wt% of Co; 0.2 wt% of Ti; 0.9 wt% of B; fe 67.29 wt%; the percentage is the mass percentage of each component in the total mass of the raw material composition.

In a preferred embodiment of the present invention, the raw material composition of the R-T-B series permanent magnetic material preferably includes the following components by mass: 22.5 wt% of Nd; pr 7.5 wt%; ga 0.65 wt%; 0.5 wt% of Cu; 0.05 wt% of Al; co1.5wt%; 0.25 wt% of Ti; b0.915 wt%; fe 66.135 wt%; the percentage is the mass percentage of each component in the total mass of the raw material composition.

In a preferred embodiment of the present invention, the raw material composition of the R-T-B series permanent magnetic material preferably includes the following components by mass: nd 22.875 wt%; pr 7.625 wt%; ga 0.55 wt%; cu 0.55 wt%; 0.05wt% of Al0; 2 wt% of Co; 0.15 wt% of Ti; b0.94 wt%; fe 65.26 wt%; the percentage is the mass percentage of each component in the total mass of the raw material composition.

In a preferred embodiment of the present invention, the raw material composition of the R-T-B series permanent magnetic material preferably includes the following components by mass: nd 23.25 wt%; pr 7.75 wt%; ga 0.55 wt%; 0.6 wt% of Cu; 0.05 wt% of Al; co2.5wt%; 0.25 wt% of Ti; b0.92 wt%; fe 64.13 wt%; the percentage is the mass percentage of each component in the total mass of the raw material composition.

In a preferred embodiment of the present invention, the raw material composition of the R-T-B series permanent magnetic material preferably includes the following components by mass: nd 24 wt%; pr 8 wt%; ga 0.75 wt%; 0.45 wt% of Cu; 0.06 wt% of Al; co0.5wt%; 0.2 wt% of Zr; b0.92 wt%; fe 65.12 wt%; the percentage is the mass percentage of each component in the total mass of the raw material composition.

In a preferred embodiment of the present invention, the raw material composition of the R-T-B series permanent magnetic material preferably includes the following components by mass: nd 24.75 wt%; pr 8.25 wt%; ga 0.85 wt%; 0.5 wt% of Cu; 0.05 wt% of Al; co1 wt%; 0.26 wt% of Zr; b0.92 wt%; fe 63.42 wt%; the percentage is the mass percentage of each component in the total mass of the raw material composition.

In a preferred embodiment of the present invention, the raw material composition of the R-T-B series permanent magnetic material preferably includes the following components by mass: nd 21.375 wt%; pr 7.125 wt%; ga 0.55 wt%; cu 0.55 wt%; 0.05wt% of Al0; 1.5 wt% of Co; 0.3 wt% of Zr; b0.92 wt%; fe 67.63 wt%; the percentage is the mass percentage of each component in the total mass of the raw material composition.

In a preferred embodiment of the present invention, the raw material composition of the R-T-B series permanent magnetic material preferably includes the following components by mass: nd 22.125 wt%; pr 7.375 wt%; ga 0.55 wt%; 0.6 wt% of Cu; 0.05 wt% of Al; 2 wt% of Co; 0.35 wt% of Zr; b0.84 wt%; fe 66.11 wt%; the percentage is the mass percentage of each component in the total mass of the raw material composition.

In a preferred embodiment of the present invention, the raw material composition of the R-T-B series permanent magnetic material preferably includes the following components by mass: 22.5 wt% of Nd; pr 7.5 wt%; ga 0.55 wt%; 0.65 wt% of Cu; 0.07 wt% of Al; co2.5wt%; 0.25 wt% of Zr; 0.9 wt% of B; fe 65.08 wt%; the percentage is the mass percentage of each component in the total mass of the raw material composition.

In a preferred embodiment of the present invention, the raw material composition of the R-T-B series permanent magnetic material preferably includes the following components by mass: nd 22.875 wt%; pr 7.625 wt%; ga 0.75 wt%; 0.65 wt% of Cu; al0.07wt%; 0.5 wt% of Co; 0.2 wt% of Zr; b0.915 wt%; fe 66.415 wt%; the percentage is the mass percentage of each component in the total mass of the raw material composition.

In a preferred embodiment of the present invention, the raw material composition of the R-T-B series permanent magnetic material preferably includes the following components by mass: nd 23.25 wt%; pr 7.75 wt%; ga 0.65 wt%; 0.7 wt% of Cu; 0.06 wt% of Al; co1 wt%; 0.26 wt% of Zr; b0.94 wt%; fe 65.39 wt%; the percentage is the mass percentage of each component in the total mass of the raw material composition.

In a preferred embodiment of the present invention, the raw material composition of the R-T-B series permanent magnetic material preferably includes the following components by mass: nd 24 wt%; pr 8 wt%; ga 1.05 wt%; 0.8 wt% of Cu; 0.06 wt% of Al; co1.5wt%; 0.3 wt% of Zr; b0.84 wt%; fe 63.45 wt%; the percentage is the mass percentage of each component in the total mass of the raw material composition.

In a preferred embodiment of the present invention, the raw material composition of the R-T-B series permanent magnetic material preferably includes the following components by mass: nd 23.75 wt%; pr 8.25 wt%; ga 1.25 wt%; 0.9 wt% of Cu; 0.06 wt% of Al; co2 wt%; 0.35 wt% of Zr; 0.9 wt% of B; fe 62.54 wt%; the percentage is the mass percentage of each component in the total mass of the raw material composition.

In a preferred embodiment of the present invention, the raw material composition of the R-T-B series permanent magnetic material preferably includes the following components by mass: nd 22.875 wt%; pr 7.625 wt%; ga 0.55 wt%; 0.4 wt% of Cu; 0.05 wt% of Al; 2.5 wt% of Co; 0.18 wt% of Ti; 0.2 wt% of Nb; b0.84 wt%; fe 64.78 wt%; the percentage is the mass percentage of each component in the total mass of the raw material composition.

In a preferred embodiment of the present invention, the raw material composition of the R-T-B series permanent magnetic material preferably includes the following components by mass: nd 23.25 wt%; pr 7.75 wt%; ga 0.75 wt%; 0.45 wt% of Cu; 0.05 wt% of Al; 0.5 wt% of Co; 0.2 wt% of Ti; 0.3 wt% of Nb; 0.9 wt% of B; fe 65.85 wt%; the percentage is the mass percentage of each component in the total mass of the raw material composition.

In a preferred embodiment of the present invention, the raw material composition of the R-T-B series permanent magnetic material preferably includes the following components by mass: nd 24 wt%; pr 8 wt%; ga 0.85 wt%; 0.5 wt% of Cu; 0.07 wt% of Al; co1 wt%; 0.4 wt% of Nb; b0.915 wt%; fe 64.265 wt%; the percentage is the mass percentage of each component in the total mass of the raw material composition.

In a preferred embodiment of the present invention, the raw material composition of the R-T-B series permanent magnetic material preferably includes the following components by mass: nd 24.75 wt%; pr 8.25 wt%; ga 0.55 wt%; cu 0.55 wt%; 0.06 wt% of Al; 1.5 wt% of Co; 0.5 wt% of Nb; b0.94 wt%; fe 62.9 wt%; the percentage is the mass percentage of each component in the total mass of the raw material composition.

In a preferred embodiment of the present invention, the raw material composition of the R-T-B series permanent magnetic material preferably includes the following components by mass: nd 21.5 wt%; 6.5 wt% of Pr; tb 2 wt%; ga 0.95 wt%; 0.45 wt% of Cu; 0.05wt% of Al0; 2 wt% of Co; 0.3 wt% of Nb; 0.9 wt% of B; fe 65.35 wt%; the percentage is the mass percentage of each component in the total mass of the raw material composition.

In a preferred embodiment of the present invention, the raw material composition of the R-T-B series permanent magnetic material preferably includes the following components by mass: nd 21.5 wt%; 6.5 wt% of Pr; dy 2 wt%; ga 1.15 wt%; 0.45 wt% of Cu; 0.06wt% of Al0; 2.5 wt% of Co; 0.35 wt% of Nb; 0.9 wt% of B; fe 64.59 wt%; the percentage is the mass percentage of each component in the total mass of the raw material composition.

The second technical scheme provided by the invention is as follows: a preparation method of an R-T-B series permanent magnetic material comprises the following steps:

and (2) carrying out casting, powder making, forming, sintering and aging treatment on the molten liquid of the raw material composition of the R-T-B series permanent magnet material.

Wherein, the melting liquid of the raw material composition of the R-T-B series permanent magnetic material can be prepared by the conventional method in the field, such as: 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 ℃.

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

Wherein, the cooling can be realized by introducing cooling water into the roller. Preferably, the water inlet temperature of the roller is less than or equal to 25 ℃, such as 23.5 ℃, 23.6 ℃, 23.7 ℃ or 23.8 ℃.

Wherein the roller can be a roller conventional in the art, such as a copper roller.

Wherein, the operation and the condition of the powder preparation can be the operation and the condition which are conventional in the field. The milling typically includes a hydrogen milling process and a jet milling process.

The hydrogen breaking process can be a hydrogen breaking process conventional in the art, and can be performed through hydrogen absorption, dehydrogenation and cooling treatment.

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

The dehydrogenation can be carried out under the condition of vacuum pumping and temperature rise.

Wherein, after the hydrogen is broken, the raw materials can be crushed by the conventional method in the field. The comminution process may be a comminution process conventional in the art, such as jet milling.

The jet mill pulverization may be performed in a nitrogen atmosphere having an oxidizing gas content of 120ppm or less. The oxidizing gas refers to oxygen or moisture content.

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

The jet mill can be used for crushing for 3 hours.

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

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

Wherein the sintering process may be a sintering process conventional in the art, for example, under vacuum conditions (e.g., at 5 × 10)^-3Pa, vacuum), preheating, sintering and cooling.

The preheating temperature can be 300-600 ℃. The preheating time can be 1-2 h. Preferably, the preheating is for 1h each at a temperature of 300 ℃ and 600 ℃.

The sintering temperature can be the conventional sintering temperature in the field, preferably 1040-1090 ℃ and more preferably 1060-1078 ℃.

The sintering time can be the sintering time conventional in the art, such as 5-10 h, and further such as 8 h.

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

Wherein the aging treatment comprises primary aging treatment and secondary aging treatment.

Wherein, the primary aging treatment can be a primary aging treatment process which is conventional in the field; preferably, the primary aging treatment is performed under high purity Ar conditions.

The primary aging treatment temperature can be the conventional primary aging treatment temperature in the field, and is preferably 850-950 ℃, and more preferably 900 ℃.

The treatment time of the primary aging can be 2-4 h, and preferably 3 h.

The temperature of the secondary aging treatment can be the temperature of the conventional secondary aging treatment in the field, preferably 430-490 ℃, more preferably 450-460 ℃, such as 450 ℃, 455 ℃ and 460 ℃.

The treatment time of the secondary aging can be 2-4 h, and preferably 3 h.

Wherein the rate of raising the temperature to the temperature of the primary or secondary aging treatment is preferably 3to 5 ℃/min. The starting point of the warming may be room temperature, for example 20 ℃.

The third technical scheme of the invention is as follows: the R-T-B series permanent magnetic material prepared by the method.

The fourth technical scheme of the invention is as follows: an R-T-B series permanent magnetic material comprises the following components in percentage by mass:

r: 28.5 to 33.0 wt%; r is a rare earth element at least containing Nd;

Ga：＞0.5wt％；

Cu：≥0.4wt％；

B：0.84～0.94wt％；

Al：0.08～0.12wt％；

co: less than or equal to 2.5 wt% but not 0;

Fe：62～70wt％；

n: one or more of Ti, Zr and Nb;

when N contains Ti, the content of Ti is 0.15-0.25 wt%;

when N contains Zr, the content of Zr is 0.2-0.35 wt%;

when the N contains Nb, the content of Nb is 0.2-0.5 wt%;

the percentage is the mass percentage of each component in the total mass of the R-T-B series permanent magnet material.

In the invention, the R-T-B series permanent magnetic material comprises R₂T₁₄B main phase, grain boundary phase and rare earth-rich phase.

Wherein the grain boundary phase refers to two or more R₂T₁₄B is a general term for grain boundary phases between grains.

Wherein, R is₂T₁₄In the B phase, R is a rare earth element, and T is Fe and/or Co.

Wherein, preferably, the grain boundary phase contains R₆T₁₃An M phase; the R is₆T₁₃In the M phase, R is a rare earth element, T is Fe and/or Co, and M is Ga and/or Cu.

In the present invention, in the R-T-B based permanent magnetic material, the content of R is preferably 29.5 to 32.5 wt%, such as 30 wt%, 30.004 wt%, 30.005 wt%, 30.009 wt%, 30.491 wt%, 30.5 wt%, 30.505 wt%, 31.004 wt%, 31.999 wt%, 32.005 wt%, 32.029 wt%, and more preferably 30 to 31.5 wt%; the percentage is the mass percentage of the total mass of the R-T-B series permanent magnet material.

Wherein, in the R-T-B series permanent magnetic material, the content of Nd is preferably 21-25 wt%, such as 21.371 wt%, 21.375 wt%, 21.503 wt%, 21.506 wt%, 22.121 wt%, 22.126 wt%, 22.502 wt%, 22.503 wt%, 22.871 wt%, 22.874 wt%, 22.876 wt%, 23.252 wt%, 23.752 wt%, 24.012 wt%, 24.032 wt%, 24.751 wt%, 24.752 wt%, more preferably 22-24 wt%; the percentage is the mass percentage of the total mass of the R-T-B series permanent magnet material.

In the R-T-B series permanent magnetic material, R can also comprise Pr.

Wherein, the content of Pr can be less than 0.2 at% or more than 8 at%; and at% is the atomic percentage in the R-T-B series permanent magnetic material.

Wherein, the content of Pr is preferably 5to 10 wt%, such as 6.503 wt%, 6.508 wt%, 7.123 wt%, 7.128 wt%, 7.371 wt%, 7.372 wt%, 7.497 wt%, 7.502 wt%, 7.62 wt%, 7.626 wt%, 7.629 wt%, 7.752 wt%, 7.987 wt%, 7.997 wt%, 8.252 wt%, 8.253 wt%, more preferably 7 to 9 wt%; the percentage is the mass percentage of the total mass of the R-T-B series permanent magnet material.

In the invention, the R-T-B series permanent magnetic material does not contain heavy rare earth elements, and can reach the level equivalent to or even better than the magnetic performance of the magnet material in the prior art. Or, the R-T-B series permanent magnetic material can also comprise RH which is a heavy rare earth element.

Wherein, when the R-T-B series permanent magnetic material contains RH, the content of the RH is preferably 1.5-6 wt%, more preferably 1-2.5 wt%, and the percentage is the mass percentage of the total mass of the R-T-B series permanent magnetic material.

Wherein, the RH preferably includes one or more of Dy, Tb and Ho.

When the RH includes Dy, the content of Dy is preferably 1 to 2.5 wt%, for example, 1.998 wt%, in terms of mass percentage based on the total mass of the R-T-B based permanent magnetic material.

When the RH includes Tb, the content of Tb is preferably 1 to 2.5 wt%, for example 1.996 wt%, which is the mass percentage of the total mass of the R-T-B series permanent magnetic material.

In the present invention, in the R-T-B based permanent magnetic material, the content of B is preferably 0.85 to 0.94 wt%, such as 0.902 wt%, 0.903 wt%, 0.904 wt%, 0.915 wt%, 0.916 wt%, 0.921 wt%, 0.922 wt%, 0.923 wt%, 0.941 wt%, 0.942 wt%, 0.945 wt%, and more preferably 0.915 to 0.94 wt%, with the percentage being mass% of the total mass of the R-T-B based permanent magnetic material.

In the R-T-B system permanent magnetic material, the atomic percentage of R and the atomic percentage of B preferably satisfy the following relationship: B/R is more than or equal to 0.38, wherein B is the atomic percentage of B in the R-T-B series permanent magnetic material, and R is the atomic percentage of R in the R-T-B series permanent magnetic material.

In the invention, in the R-T-B based permanent magnetic material, when R further includes Pr, preferably, B and Nd satisfy the following relation: B/(Pr + Nd) is not less than 0.405, wherein B refers to the atomic percent of B in the R-T-B series permanent magnetic material, Pr refers to the atomic percent of Pr in the R-T-B series permanent magnetic material, and Nd refers to the atomic percent of Nd in the R-T-B series permanent magnetic material.

In the present invention, the content of Ga in the R-T-B based permanent magnetic material is preferably 0.55 to 1.5 wt%, for example, 0.55 wt%, 0.551 wt%, 0.552 wt%, 0.553 wt%, 0.554 wt%, 0.6 wt%, 0.65 wt%, 0.652 wt%, 0.75 wt%, 0.751 wt%, 0.753 wt%, 0.851 wt%, 0.852 wt%, 0.95 wt%, 1.05 wt%, 1.153 wt%, 1.253 wt%, more preferably 1.05 to 1.5 wt%, in terms of mass% based on the total mass of the R-T-B based permanent magnetic material.

In the present invention, in the R-T-B based permanent magnetic material, the atomic ratio of Ga to B preferably satisfies the following conditions Ga > 7.2941-1.24B (at%), and Ga 0.55 wt% to Ga < 1.05 wt%.

In the present invention, the content of Cu in the R-T-B based permanent magnetic material is preferably 0.45 to 1 wt%, for example, 0.45 wt%, 0.451 wt%, 0.452 wt%, 0.5 wt%, 0.503 wt%, 0.55 wt%, 0.552 wt%, 0.6 wt%, 0.65 wt%, 0.7 wt%, 0.8 wt%, 0.9 wt%, more preferably 0.65 to 0.9 wt%, in mass% based on the total mass of the R-T-B based permanent magnetic material.

In the present invention, the content of Al in the R-T-B based permanent magnetic material is preferably 0.09 to 0.12 wt%, for example, 0.091 wt%, 0.092 wt%, 0.093 wt%, 0.094 wt%, 0.103 wt%, 0.108 wt%, 0.115 wt%, and more preferably 0.09 to 0.11 wt%, based on the total mass of the R-T-B based permanent magnetic material.

In the present invention, the content of Co in the R-T-B based permanent magnet material is preferably 0.5 to 2.5 wt%, for example, 0.502 wt%, 0.503 wt%, 0.504 wt%, 0.996 wt%, 1.012 wt%, 1.014 wt%, 1.501 wt%, 1.502 wt%, 1.503 wt%, 1.992 wt%, 1.993 wt%, 2.012 wt%, more preferably 1.00 to 2.00 wt%, in percentage by mass based on the total mass of the R-T-B based permanent magnet material.

In the present invention, in the R-T-B based permanent magnetic material, the content of Fe is preferably 64 to 69 wt%, for example, 64.079 wt%, 64.2 wt%, 64.536 wt%, 64.736 wt%, 65.082 wt%, 65.272 wt%, 65.31 wt%, 65.363 wt%, 65.796 wt%, 66.086 wt%, 66.097 wt%, 66.361 wt%, 67.249 wt%, 67.645 wt%, 68.964 wt%, more preferably 64 to 69 wt%, based on the total mass of the R-T-B based permanent magnetic material.

In the present invention, when the N includes Ti, the content of Ti in the R-T-B based permanent magnetic material is preferably 0.2 to 0.25 wt%, for example, 0.202 wt%, 0.203 wt%, which is a mass percentage of the total mass of the R-T-B based permanent magnetic material.

In the present invention, when the N in the R-T-B based permanent magnetic material contains Zr, the Zr content is preferably 0.25 to 0.35 wt%, for example, 0.252 wt%, 0.257 wt%, 0.261 wt%, 0.302 wt%, and the percentage is a mass percentage based on the total mass of the R-T-B based permanent magnetic material.

In the invention, when the N comprises Zr in the R-T-B series permanent magnet material, the Zr content is preferably 0.26 wt% to Zr (3.48B-2.67 wt%), wherein B is the mass percentage of the B in the total mass of the R-T-B series permanent magnet material.

In the present invention, in the R-T-B based permanent magnetic material, when the N includes Nb, the content of Nb is preferably 0.2 to 0.3 wt%, for example, 0.201 wt%, 0.295 wt%, 0.297 wt%, and the percentage is a mass percentage of the total mass of the R-T-B based permanent magnetic material.

In the invention, in the R-T-B series permanent magnet material, when the N comprises Ti and Nb, the atom percentage of the Ti or the Nb is preferably more than or equal to 0.55 at%.

In the invention, the R-T-B series permanent magnetic material preferably comprises the following components in percentage by mass:

r: 29.5 to 32.5 wt%; r is a rare earth element at least containing Nd;

Ga：0.55～1.5wt％；

Cu：0.45～1wt％；

B：0.85～0.94wt％；

Al：0.09～0.12wt％；

Co：0.5～2.5wt％；

Fe：64～69wt％；

n: one or more of Ti, Zr and Nb;

when N contains Ti, the content of Ti is 0.2-0.25 wt%;

when N contains Zr, the content of Zr is 0.25-0.35 wt%;

when the N contains Nb, the content of Nb is 0.2-0.3 wt%;

r: 29.5 to 32.5 wt%; r is a rare earth element comprising Nd and Pr;

Pr：5～10wt％；

Ga：0.55～1.5wt％；

Cu：0.45～1wt％；

B：0.85～0.94wt％；

Al：0.09～0.12wt％；

Co：0.5～2.5wt％；

Fe：64～69wt％；

n: one or more of Ti, Zr and Nb;

when N contains Ti, the content of Ti is 0.2-0.25 wt%;

when N contains Zr, the content of Zr is 0.25-0.35 wt%;

when the N contains Nb, the content of Nb is 0.2-0.3 wt%;

r: 29.5 to 32.5 wt%; r is a rare earth element comprising Nd and Pr;

Pr：5～10wt％；

Ga：0.55～1.5wt％；

Cu：0.45～1wt％；

B：0.85～0.94wt％；

Al：0.09～0.12wt％；

Co：0.5～2.5wt％；

Fe：64～69wt％；

Ti：0.2～0.25wt％；

r: 29.5 to 32.5 wt%; r is a rare earth element at least containing Nd;

Ga：0.55～1.5wt％；

Cu：0.45～1wt％；

B：0.85～0.94wt％；

Al：0.09～0.12wt％；

Co：0.5～2.5wt％；

Fe：64～69wt％；

Zr：0.25～0.35wt％；

r: 29.5 to 32.5 wt%; r is a rare earth element at least containing Nd;

Ga：0.55～1.5wt％；

Cu：0.45～1wt％；

B：0.85～0.94wt％；

Al：0.09～0.12wt％；

Co：0.5～2.5wt％；

Fe：64～69wt％；

Nb：0.2～0.3wt％；

In a preferred embodiment of the present invention, the R-T-B is a permanent magnetic material, preferably comprising the following components by mass: nd 21.375 wt%; pr 7.123 wt%; ga 0.551 wt%; cu 0.404 wt%; 0.081 wt% of Al; co0.504wt%; 0.154 wt% of Ti; b0.844 wt%; fe 68.964 wt%; the percentage is the mass percentage of each component in the total mass of the R-T-B series permanent magnet material.

In a preferred embodiment of the present invention, the R-T-B is a permanent magnetic material, preferably comprising the following components by mass: nd 22.121 wt%; pr 7.371 wt%; ga 0.6 wt%; 0.45 wt% of Cu; 0.092 wt% of Al; co1.012wt%; 0.203 wt% of Ti; b0.902 wt%; fe 67.249 wt%; the percentage is the mass percentage of each component in the total mass of the R-T-B series permanent magnet material.

In a preferred embodiment of the present invention, the R-T-B is a permanent magnetic material, preferably comprising the following components by mass: nd 22.503 wt%; pr 7.479 wt%; ga 0.65 wt%; 0.5 wt% of Cu; 0.083 wt% of Al; co1.502wt%; 0.252 wt% of Ti; b0.916 wt%; fe 66.097 wt%; the percentage is the mass percentage of each component in the total mass of the R-T-B series permanent magnet material.

In a preferred embodiment of the present invention, the R-T-B is a permanent magnetic material, preferably comprising the following components by mass: nd 22.871 wt%; pr 7.62 wt%; ga 0.55 wt%; cu 0.55 wt%; al 0.082 wt%; co2.012wt%; ti 0.152 wt%; 0.941 wt% of B; fe 65.222 wt%; the percentage is the mass percentage of each component in the total mass of the R-T-B series permanent magnet material.

In a preferred embodiment of the present invention, the R-T-B is a permanent magnetic material, preferably comprising the following components by mass: nd 23.252 wt%; pr 7.752 wt%; ga 0.552 wt%; 0.6 wt% of Cu; al 0.091 wt%; 2.502wt% of Co2; 0.251 wt% of Ti; 0.921 wt% of B; fe 64.079 wt%; the percentage is the mass percentage of each component in the total mass of the R-T-B series permanent magnet material.

In a preferred embodiment of the present invention, the R-T-B is a permanent magnetic material, preferably comprising the following components by mass: nd 24.012 wt%; pr 7.987 wt%; ga 0.75 wt%; 0.45 wt% of Cu; 0.093 wt% of Al; co0.502wt%; 0.202 wt% of Zr; b0.922 wt%; fe 65.082 wt%; the percentage is the mass percentage of each component in the total mass of the R-T-B series permanent magnet material.

In a preferred embodiment of the present invention, the R-T-B is a permanent magnetic material, preferably comprising the following components by mass: nd 24.751 wt%; pr 8.252 wt%; ga 0.851 wt%; 0.5 wt% of Cu; 0.081 wt% of Al; co0.996wt%; zr 0.261 wt%; 0.921 wt% of B; fe 63.387 wt%; the percentage is the mass percentage of each component in the total mass of the R-T-B series permanent magnet material.

In a preferred embodiment of the present invention, the R-T-B is a permanent magnetic material, preferably comprising the following components by mass: nd 21.371 wt%; pr 7.128 wt%; ga 0.549 wt%; cu 0.55 wt%; al 0.082 wt%; co1.502wt%; 0.302 wt% of Zr; b0.923 wt%; fe 67.593 wt%; the percentage is the mass percentage of each component in the total mass of the R-T-B series permanent magnet material.

In a preferred embodiment of the present invention, the R-T-B is a permanent magnetic material, preferably comprising the following components by mass: nd 22.126 wt%; pr 7.372 wt%; ga 0.548 wt%; 0.6 wt% of Cu; 0.083 wt% of Al; co1.993wt%; zr 0.351 wt%; b0.841 wt%; fe 66.086 wt%; the percentage is the mass percentage of each component in the total mass of the R-T-B series permanent magnet material.

In a preferred embodiment of the present invention, the R-T-B is a permanent magnetic material, preferably comprising the following components by mass: nd 22.502 wt%; pr 7.502 wt%; ga 0.553 wt%; 0.65 wt% of Cu; 0.103 wt% of Al; co2.503wt%; 0.252 wt% of Zr; b0.903 wt%; fe 65.032 wt%; the percentage is the mass percentage of each component in the total mass of the R-T-B series permanent magnet material.

In a preferred embodiment of the present invention, the R-T-B is a permanent magnetic material, preferably comprising the following components by mass: nd 22.874 wt%; pr 7.626 wt%; ga 0.753 wt%; 0.65 wt% of Cu; 0.115 wt% of Al; co0.503wt%; 0.203 wt% of Zr; b0.915 wt%; fe 66.361 wt%; the percentage is the mass percentage of each component in the total mass of the R-T-B series permanent magnet material.

In a preferred embodiment of the present invention, the R-T-B is a permanent magnetic material, preferably comprising the following components by mass: nd 23.252 wt%; pr 7.752 wt%; ga 0.652 wt%; 0.7 wt% of Cu; 0.083 wt% of Al; co0.996wt%; zr 0.257 wt%; b0.945 wt%; fe 65.363 wt%; the percentage is the mass percentage of each component in the total mass of the R-T-B series permanent magnet material.

In a preferred embodiment of the present invention, the R-T-B is a permanent magnetic material, preferably comprising the following components by mass: nd 24.012 wt%; pr 7.987 wt%; ga 1.05 wt%; 0.8 wt% of Cu; al 0.091 wt%; co1.503wt%; 0.302 wt% of Zr; b0.842 wt%; fe 63.413 wt%; the percentage is the mass percentage of each component in the total mass of the R-T-B series permanent magnet material.

In a preferred embodiment of the present invention, the R-T-B is a permanent magnetic material, preferably comprising the following components by mass: nd 23.752 wt%; pr 8.253 wt%; ga 1.253 wt%; 0.9 wt% of Cu; 0.092 wt% of Al; co2.012wt%; zr 0.351 wt%; b0.903 wt%; fe 62.484 wt%; the percentage is the mass percentage of each component in the total mass of the R-T-B series permanent magnet material.

In a preferred embodiment of the present invention, the R-T-B is a permanent magnetic material, preferably comprising the following components by mass: nd 22.876 wt%; pr 7.629 wt%; ga 0.55 wt%; cu 0.404 wt%; al 0.082 wt%; 2.502wt% of Co2; 0.178 wt% of Ti; 0.201 wt% of Nb; b0.842 wt%; fe 64.736 wt%; the percentage is the mass percentage of each component in the total mass of the R-T-B series permanent magnet material.

In a preferred embodiment of the present invention, the R-T-B is a permanent magnetic material, preferably comprising the following components by mass: nd 23.252 wt%; pr 7.752 wt%; ga 0.751 wt%; cu 0.452 wt%; 0.092 wt% of Al; co0.503wt%; 0.202 wt% of Ti; nb 0.297 wt%; b0.903 wt%; fe 65.796 wt%; the percentage is the mass percentage of each component in the total mass of the R-T-B series permanent magnet material.

In a preferred embodiment of the present invention, the R-T-B is a permanent magnetic material, preferably comprising the following components by mass: nd 24.032 wt%; pr 7.997 wt%; ga 0.852 wt%; cu 0.503 wt%; al 0.091 wt%; co1.014wt%; nb 0.395 wt%; b0.916 wt%; fe 64.2 wt%; the percentage is the mass percentage of each component in the total mass of the R-T-B series permanent magnet material.

In a preferred embodiment of the present invention, the R-T-B is a permanent magnetic material, preferably comprising the following components by mass: nd 24.752 wt%; pr 8.252 wt%; ga 0.554 wt%; cu 0.552 wt%; 0.108 wt% of Al; co1.501wt%; 0.501 wt% of Nb; b0.942 wt%; fe 62.838 wt%; the percentage is the mass percentage of each component in the total mass of the R-T-B series permanent magnet material.

In a preferred embodiment of the present invention, the R-T-B is a permanent magnetic material, preferably comprising the following components by mass: nd 21.506 wt%; pr 6.503 wt%; tb 1.996 wt%; ga 0.95 wt%; cu 0.452 wt%; al0.092wt%; co 1.992 wt%; 0.295 wt% of Nb; b0.904 wt%; fe 65.31 wt%; the percentage is the mass percentage of each component in the total mass of the R-T-B series permanent magnet material.

In a preferred embodiment of the present invention, the R-T-B is a permanent magnetic material, preferably comprising the following components by mass: nd 21.503 wt%; pr 6.508 wt%; 1.998 wt% of Dy; ga 1.153 wt%; cu 0.451 wt%; al0.094wt%; co2.502 wt%; nb 0.351 wt%; b0.904 wt%; fe 64.536 wt%; the percentage is the mass percentage of each component in the total mass of the R-T-B series permanent magnet material.

The fifth technical scheme of the invention is as follows: the application of the R-T-B series permanent magnetic material as an electronic component.

The application field can be the automobile driving field, the wind power field, the servo motor field and the household appliance field (such as an air conditioner).

In the present invention, the room temperature means 25 ℃. + -. 5 ℃.

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 magnetic property, wherein Br is more than or equal to 12.97kGs, Hcj is more than or equal to 18.9kOe, after heavy rare earth elements are added, Hcj can reach 28.35kOe and 25.9kOe, the temperature stability of a magnet is good, and the absolute value of the Br temperature coefficient of α%/° C at 20-80 ℃ is less than 0.104.

(2) The R-T-B series permanent magnetic material can generate 6-13-1 phase, and has low relative magnetic conductivity, higher squareness and good consistency of magnet performance.

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.

Examples 1 to 20 and comparative examples 1 to 7

The raw materials used for preparing the R-T-B series permanent magnetic materials in examples 1 to 20 and comparative examples 1 to 7 are shown in table 1, and the preparation process thereof is as follows:

(1) and (3) smelting: according to the formulation shown in Table 1, the prepared raw materials were put into a crucible made of alumina, and placed in a high-frequency vacuum induction melting furnace at 5X 10^-2Vacuum melting is carried out in vacuum of Pa at the temperature of below 1500 ℃ to obtain molten liquid.

(2) The casting process comprises the following steps: introducing Ar gas into a smelting furnace after vacuum smelting to ensure that the air pressure reaches 5.5 ten thousand Pa, casting, and making the molten liquid into a rapid hardening alloy sheet with the thickness of 0.12-0.35mm by a copper roller with the rotation speed of 29 revolutions per minute, wherein in the casting process, chilled water needs to be introduced into the copper roller, and the water inlet temperature is less than or equal to 25 ℃.

(3) Hydrogen crushing and crushing: vacuumizing the hydrogen breaking furnace in which the quenching alloy is placed at room temperature, introducing hydrogen with the purity of 99.9% into the hydrogen breaking furnace, maintaining the hydrogen pressure at 0.15MPa, fully absorbing hydrogen, vacuumizing while heating, fully dehydrogenating, cooling, and taking out the powder after hydrogen breaking and crushing.

(4) A micro-grinding process: the powder after hydrogen crushing was pulverized by jet milling for 3 hours under a nitrogen atmosphere having an oxidizing gas content of 120ppm or less and a pressure in the pulverization chamber of 0.38MPa to obtain a fine powder. The oxidizing gas refers to oxygen or moisture.

(5) Adding zinc stearate into the powder crushed by the jet mill, wherein the adding amount of the zinc stearate is 0.12 percent of the weight of the mixed powder, and then fully mixing the zinc stearate and the mixed powder by using a V-shaped mixer.

(6) Magnetic field forming process: using a magnetic field forming machine of a perpendicular orientation type, in an orientation magnetic field of 1.6T, at 0.35ton/cm²The powder added with zinc stearate was once formed into a cube with a side length of 25mm under the molding pressure of (1), and demagnetized in a magnetic field of 0.2T after the primary molding. The molded article after the primary molding was sealed so as not to contact air, and then subjected to secondary molding (isostatic pressing) at 1.3ton/cm²Secondary forming is performed under pressure of (1).

(7) And (3) sintering: the molded bodies were transferred to a sintering furnace and sintered at 5X 10^-3Keeping the temperature of the mixture at 300 ℃ and 600 ℃ for 1 hour respectively under the vacuum of Pa, sintering the mixture at 1050-1090 ℃ for 8 hours, introducing Ar gas to enable the pressure to reach 0.1MPa, and cooling the mixture to the room temperature.

(8) And (3) aging treatment process: heating the sintered body from 20 ℃ to 900 ℃ at a heating rate of 3-5 ℃/min in high-purity Ar gas to perform primary aging treatment; then, carrying out secondary aging treatment for 3h, wherein the temperature rise rate from room temperature to the secondary aging temperature is 3-5 ℃/min;

wherein, the water inlet temperature of the copper roller in the casting process in the step (2), the sintering temperature in the step (7) and the secondary aging treatment temperature in the step (8) are shown in the table 2.

TABLE 1 quality percentages of raw materials in examples 1-20 and comparative examples 1-7

Note: TRE refers to the total rare earth content, including Nd, Pr, and heavy rare earths (Tb, Dy); "/" means that the element is not included.

The raw materials were prepared according to the formulation shown in Table 1, and the process conditions were the same except for the conditions shown in Table 2, to obtain R-T-B sintered magnets.

TABLE 2

Effect example 1 ingredient measurement

The sintered magnets of examples 1 to 20 and comparative examples 1 to 7 were measured for specific components using a high-frequency inductively coupled plasma emission spectrometer (ICP-OES). The following table shows the results of the component detection.

TABLE 3

Note: TRE refers to the total rare earth content, including Nd, Pr, and heavy rare earths (Tb, Dy); the Al content in the sintered magnets of examples 1 to 20 and comparative examples 1 to 7 is the sum of the Al content in the raw material and the Al content introduced in other raw materials and processes (e.g., crucible of alumina during melting).

Effect example 2 magnetic Properties and consistency of magnetic Properties

The sintered magnet is subjected to magnetic property detection by using an NIM-10000H type BH bulk rare earth permanent magnet nondestructive measurement system of China measurement institute. Table 4 shows the results of magnetic property measurements. Wherein,

(1) the detection method of the 6-13-1 phase comprises the following steps:

microstructure: the perpendicular orientation plane of the R-T-B system permanent magnetic material was polished by FE-EPMA detection, and detected by field emission electron probe microanalyzer (FE-EPMA) (JEOL 8530F, Japan Electron Ltd.). Detection of R in grain boundaries₆T₁₃M phase, T Fe and/or Co, M Ga and/or Cu.

(2) Br, Hcj, 20-80 ℃ Br temperature coefficient, 20-80 ℃ Hcj temperature coefficient, 20-150 ℃ Hcj temperature coefficient, squareness degree and relative permeability are all mean values: the average value is calculated by testing the remanence, the coercive force, the Br temperature coefficient at 20-80 ℃, the Hcj temperature coefficient at 20-150 ℃ and the squareness or the relative permeability of 5 parts of R-T-B series permanent magnetic material samples in the same batch. In each of examples and comparative examples of the present invention, a plurality of R-T-B-based permanent magnetic materials were prepared, and the same lot refers to a plurality of R-T-B-based permanent magnetic materials obtained in each of examples and comparative examples, wherein the R-T-B-based permanent magnetic materials used for the test were 10 × 10mm cylinders.

TABLE 4

Note: the magnetic properties of the R-T-B series permanent magnet materials in the comparative examples 1-7 are the best properties obtained by the formula of the comparative examples 1-7 after the secondary aging temperature optimization.

Table 5 shows the results of the magnetic property uniformity measurement. Wherein,

(1) squareness SQ ═ Hk/Hcj; wherein, Hk is the value of the corresponding external magnetic field H when B is 90% Br; hcj is the coercivity.

(2) The relative magnetic permeability is Br/Hcb; wherein Br is remanence, Hcb is magnetic induction coercive force, and when an inflection point exists in a B-H curve, the magnetic conductivity is taken before the inflection point.

(3) Max (Max hcj) -Min (hcj): and subtracting the minimum value of the coercive force from the maximum value of the coercive force in the same batch of products, wherein if the minimum value of the coercive force is more than 1.5kOe, the consistency of the magnetic performance is poor.

TABLE 5

As can be seen from Table 5, the coercivity difference of the magnetic steel products in the comparative examples 1-3 in the same batch is greater than 1.5kOe, namely Max (Hcj) -Min (Hcj) is greater than 1.5kOe, and the magnet performance consistency can be judged to be poor; the R-T-B series permanent magnetic materials in the embodiments 1-20 have low relative magnetic permeability and high squareness, and the magnetic steel products have low coercive force difference value in the same batch and good magnet performance consistency.

Claims

1. A raw material composition of an R-T-B series permanent magnetic material is characterized by comprising the following components in percentage by mass:

r: 28.5 to 33.0 wt%; r is a rare earth element at least containing Nd;

Ga：＞0.5wt％；

Cu：≥0.4wt％；

B：0.84～0.94wt％；

Al：0.05～0.07wt％；

co: less than or equal to 2.5 wt% but not 0;

Fe：62～70wt％；

n: one or more of Ti, Zr and Nb;

when N contains Ti, the content of Ti is 0.15-0.25 wt%;

when N contains Zr, the content of Zr is 0.2-0.35 wt%;

when the N contains Nb, the content of Nb is 0.2-0.5 wt%;

2. The raw material composition according to claim 1, wherein the content of R in the raw material composition is 29.5 to 32.5 wt%, preferably 30.5 to 32 wt%, and the percentage is mass percentage based on the total mass of the raw material composition;

and/or the content of Nd is 21-25 wt%, preferably 22-24 wt%, and the percentage is the mass percentage of the total mass of the raw material composition;

and/or in the raw material composition, the R comprises Pr;

wherein, when the R comprises Pr, the content of the Pr is less than 0.2 at% or more than 8 at%; at% is the atomic percentage in the feedstock composition;

wherein, when the R comprises Pr, the content of the Pr is preferably 5-10 wt%, and more preferably 7-9 wt%; the percentage is the mass percentage of the total mass of the raw material composition;

and/or the raw material composition comprises RH which is a heavy rare earth element;

when the raw material composition contains RH, the content of the RH is preferably 1.5-6 wt%, more preferably 1-2.5 wt%, and the percentage is the mass percentage of the total mass of the raw material composition;

wherein the RH preferably includes one or more of Dy, Tb and Ho;

when the RH comprises Dy, the content of Dy is preferably 1-2.5 wt%, and the percentage is the mass percentage of the total mass of the raw material composition;

when the RH comprises Tb, the content of Tb is preferably 1-2.5 wt%, and the percentage is the mass percentage of the total mass of the raw material composition;

and/or the content of B is 0.85-0.94 wt%, more preferably 0.915-0.94 wt%, and the percentage is the mass percentage of the total mass of the raw material composition;

and/or the atomic percent of R and the atomic percent of B in the raw material composition satisfy the following relational expression: B/R is more than or equal to 0.38, wherein B is the atomic percent of B in the raw material composition, and R is the atomic percent of R in the raw material composition;

and/or, when the R further comprises Pr, the B and the Nd satisfy the following relational expression: B/(Pr + Nd) is not less than 0.405, wherein B is the atomic percent of B in the raw material composition, Pr is the atomic percent of Pr in the raw material composition, and Nd is the atomic percent of Nd in the raw material composition;

and/or the content of Ga is 0.55-1.5 wt%, preferably 1.05-1.5 wt%, and the percentage is the mass percentage of the total mass of the raw material composition; or Ga is more than 7.2941-1.24B (at%) and 0.55 wt% to Ga is less than 1.05 wt%;

and/or the Cu content is 0.45-1 wt%, preferably 0.65-0.9 wt%, and the percentage is the mass percentage of the total mass of the raw material composition;

and/or the content of Al is 0.06-0.07 wt%, preferably 0.06 wt%, and the percentage is the mass percentage of the total mass of the raw material composition;

and/or the content of Co is 0.5-2.5 wt%, preferably 1.00-2 wt%, and the percentage is the mass percentage of the total mass of the raw material composition;

and/or the Fe content is 64-69 wt%, and the percentage is the mass percentage of the total mass of the raw material composition;

and/or when the N contains Ti, the content of the Ti is 0.2-0.25 wt%, and the percentage is the mass percentage of the total mass of the raw material composition;

and/or when the N contains Zr, the content of the Zr is 0.25-0.35 wt%, and the percentage is the mass percentage of the total mass of the raw material composition; or the mass content of Zr is preferably more than or equal to 0.26 wt% and less than (3.48B-2.67 wt%), wherein B is the mass percent of B in the total mass of the raw material composition;

and/or when the N contains Nb, the content of Nb is 0.2-0.3 wt%, and the percentage is the mass percentage of the total mass of the raw material composition;

and/or, when the N contains Ti and/or Nb, the atomic percent of the Ti or the Nb is more than or equal to 0.55at percent.

3. The raw material composition of claim 1 or 2, wherein the raw material composition of the R-T-B series permanent magnetic material comprises the following components by mass: r: 29.5 to 32.5 wt%; r is a rare earth element at least containing Nd; ga: 0.55-1.5 wt%; cu: 0.45-1 wt%; b: 0.85-0.94 wt%; al: 0.06-0.07 wt%; co: 0.5-2.5 wt%; fe: 64 to 69 wt%; n: one or more of Ti, Zr and Nb; when N contains Ti, the content of Ti is 0.2-0.25 wt%; when N contains Zr, the content of Zr is 0.25-0.35 wt%; when the N contains Nb, the content of Nb is 0.2-0.3 wt%; the percentage is the mass percentage of each component in the total mass of the raw material composition;

or the raw material composition of the R-T-B series permanent magnet material comprises the following components in percentage by mass: r: 29.5 to 32.5 wt%; r is a rare earth element comprising Nd and Pr; pr: 5-10 wt%; ga: 0.55-1.5 wt%; cu: 0.45-1 wt%; b: 0.85-0.94 wt%; al: 0.061.51.5-0.07 wt%; co: 0.5-2.5 wt%; fe: 64 to 69 wt%; n: one or more of Ti, Zr and Nb; when N contains Ti, the content of Ti is 0.2-0.25 wt%; when N contains Zr, the content of Zr is 0.25-0.35 wt%; when the N contains Nb, the content of Nb is 0.2-0.3 wt%; the percentage is the mass percentage of each component in the total mass of the raw material composition;

or the raw material composition of the R-T-B series permanent magnet material comprises the following components in percentage by mass: r: 29.5 to 32.5 wt%; r is a rare earth element comprising Nd and Pr; ga: 0.55-1.5 wt%; cu: 0.45-1 wt%; b: 0.85-0.94 wt%; al: 0.06-0.07 wt%; co: 0.5-2.5 wt%;

fe: 64 to 69 wt%; ti: 0.2-0.25 wt%; the percentage is the mass percentage of each component in the total mass of the raw material composition;

or the raw material composition of the R-T-B series permanent magnet material comprises the following components in percentage by mass: r: 29.5 to 32.5 wt%; r is a rare earth element at least containing Nd; ga: 0.55-1.5 wt%; cu: 0.45-1 wt%; b: 0.85-0.94 wt%; al: 0.06-0.07 wt%; co: 0.5-2.5 wt%; fe: 64 to 69 wt%; zr: 0.25-0.35 wt%; the percentage is the mass percentage of each component in the total mass of the raw material composition;

or the raw material composition of the R-T-B series permanent magnet material comprises the following components in percentage by mass: r: 29.5 to 32.5 wt%; r is a rare earth element at least containing Nd; ga: 0.55-1.5 wt%; cu: 0.45-1 wt%; b: 0.85-0.94 wt%; al: 0.06-0.07 wt%; co: 0.5-2.5 wt%; fe: 64 to 69 wt%; nb: 0.2-0.3 wt%; the percentage is the mass percentage of each component in the total mass of the raw material composition.

4. A preparation method of an R-T-B series permanent magnetic material is characterized by comprising the following steps: the raw material composition of the R-T-B series permanent magnet material according to any one of claims 1 to 3 is subjected to casting, milling, forming, sintering and aging treatment.

5. The method of claim 4, wherein the casting further comprises melting;

wherein the smelting temperature is preferably below 1500 ℃;

and/or said casting is at 10²DEG C/sec-10⁴Cooling at a speed of DEG C/second;

and/or the water inlet temperature of the roller in the casting process is less than or equal to 25 ℃;

and/or, the milling comprises a hydrogen crushing process and an airflow milling process;

wherein the hydrogen breaking process comprises hydrogen absorption, dehydrogenation and cooling treatment;

wherein the hydrogen absorption is carried out under the condition that the hydrogen pressure is 0.15 MPa;

wherein the jet mill pulverization is carried out in a nitrogen atmosphere having an oxidizing gas content of 120ppm or less;

wherein the pressure of a crushing chamber for crushing by the jet mill is 0.38 MPa;

wherein the jet mill is used for crushing for 3 hours;

after the crushing, adding a lubricant into the powder; the lubricant is preferably zinc stearate; the addition amount of the lubricant is preferably 0.10-0.15% of the weight of the mixed powder;

and/or the forming process is a magnetic field forming method or a hot-pressing hot-deformation method;

and/or, the sintering also comprises preheating; the preheating temperature is preferably 300-600 ℃; the preheating time is preferably 1-2 h; the preheating is preferably carried out at the temperature of 300 ℃ and the temperature of 600 ℃ for 1 hour respectively;

and/or the sintering temperature is 1040-1090 ℃, preferably 1060-1078 ℃;

and/or the sintering time is 5-10 h, preferably 8 h;

and/or the aging treatment comprises primary aging treatment and secondary aging treatment;

wherein, the primary aging treatment is preferably carried out under the condition of high-purity Ar;

wherein the temperature of the primary aging treatment is preferably 850-950 ℃, and more preferably 900 ℃;

the treatment time of the primary aging is preferably 2-4 h, and more preferably 3 h;

wherein the temperature of the secondary aging treatment is 430-490 ℃, preferably 450-460 ℃;

the treatment time of the secondary aging is preferably 2-4 h, and more preferably 3 h;

wherein the rate of heating to the temperature of the primary or secondary aging treatment is preferably 3-5 ℃/min.

6. An R-T-B series permanent magnetic material produced by the production method according to claim 4 or 5.

7. An R-T-B series permanent magnetic material is characterized by comprising the following components in percentage by mass: r: 28.5 to 33.0 wt%; r is a rare earth element at least containing Nd;

Ga：＞0.5wt％；

Cu：≥0.4wt％；

B：0.84～0.94wt％；

Al：0.08～0.12wt％；

co: less than or equal to 2.5 wt% but not 0;

Fe：62～70wt％；

n: one or more of Ti, Zr and Nb;

when N contains Ti, the content of Ti is 0.15-0.25 wt%;

when N contains Zr, the content of Zr is 0.2-0.35 wt%;

when the N contains Nb, the content of Nb is 0.2-0.5 wt%;

8. The R-T-B series permanent magnetic material according to claim 7, wherein the R-T-B series permanent magnetic material comprises R₂T₁₄B main phase, grain boundary phase and rare earth-rich phase;

preferably, the grain boundary phase contains R₆T₁₃An M phase;

and/or the content of R is 29.5-32.5 wt%, preferably 30-31.5 wt%, and the percentage is the mass percentage of the total mass of the R-T-B series permanent magnet material;

and/or the content of Nd is 21-25 wt%, preferably 22-24 wt%, and the percentage is the mass percentage of the total mass of the R-T-B series permanent magnet material;

and/or, the R comprises Pr;

wherein, when the R comprises Pr, the content of the Pr is less than 0.2 at% or more than 8 at%; at% is the atomic percentage in the R-T-B series permanent magnetic material;

wherein, when the R comprises Pr, the content of the Pr is preferably 5-10 wt%, and more preferably 7-9 wt%; the percentage is the mass percentage of the total mass of the R-T-B series permanent magnetic material;

and/or the R-T-B series permanent magnetic material comprises RH which is a heavy rare earth element;

when the R-T-B series permanent magnet material contains RH, the content of the RH is 1.5-6 wt%, preferably 1-2.5 wt%, and the percentage is the mass percentage of the total mass of the R-T-B series permanent magnet material;

wherein the RH preferably includes one or more of Dy, Tb and Ho;

when the RH contains Dy, the content of Dy is preferably 1-2.5 wt%, and the percentage is the mass percentage of the total mass of the R-T-B series permanent magnet material;

when the RH comprises Tb, the content of Tb is preferably 1-2.5 wt%, and the percentage is the mass percentage of the total mass of the R-T-B series permanent magnet material;

and/or the content of B is 0.85-0.94 wt%, more preferably 0.915-0.94 wt%, and the percentage is the mass percentage of the total mass of the R-T-B series permanent magnetic material;

and/or the atomic percent of R and the atomic percent of B in the R-T-B series permanent magnetic material satisfy the following relational expression: B/R is more than or equal to 0.38, wherein B is the atomic percentage of B in the R-T-B series permanent magnetic material, and R is the atomic percentage of R in the R-T-B series permanent magnetic material;

and/or, when the R further comprises Pr, the B and the Nd satisfy the following relational expression: B/(Pr + Nd) is not less than 0.405, wherein B is the atomic percent of B in the R-T-B series permanent magnetic material, Pr is the atomic percent of Pr in the R-T-B series permanent magnetic material, and Nd is the atomic percent of Nd in the R-T-B series permanent magnetic material;

and/or the content of Ga is 0.55-1.5 wt%, preferably 1.05-1.5 wt%, and the percentage is the mass percentage of the total mass of the R-T-B series permanent magnetic material; or Ga is more than 7.2941-1.24B (at%) and 0.55 wt% to Ga is less than 1.05 wt%;

and/or the content of Cu is 0.45-1 wt%, preferably 0.65-0.9 wt%, and the percentage is the mass percentage of the total mass of the R-T-B series permanent magnet material;

and/or the content of Al is 0.06-0.07 wt%, preferably 0.06 wt%; the percentage is the mass percentage of the total mass of the R-T-B series permanent magnetic material;

and/or the content of Co is 0.5-2.5 wt%, preferably 1.00-2 wt%, and the percentage is the mass percentage of the total mass of the R-T-B series permanent magnet material;

and/or the content of Fe is 64-69 wt%; the percentage is the mass percentage of the total mass of the R-T-B series permanent magnetic material;

and/or when the N contains Ti, the content of the Ti is 0.2-0.25 wt%, and the percentage is the mass percentage of the total mass of the R-T-B series permanent magnet material;

and/or when the N contains Zr, the content of the Zr is 0.25-0.35 wt%, and the percentage is the mass percentage of the total mass of the R-T-B series permanent magnet material; or the mass content of Zr is preferably more than or equal to 0.26 wt% and less than (3.48B-2.67 wt%), wherein B is the mass percentage of B in the total mass of the R-T-B series permanent magnetic material;

and/or when the N comprises Nb, the content of Nb is 0.2-0.3 wt%, and the percentage is the mass percentage of the total mass of the R-T-B series permanent magnet material;

9. The R-T-B series permanent magnetic material as claimed in claim 7 or 8, wherein the R-T-B series permanent magnetic material comprises the following components in percentage by mass: r: 29.5 to 32.5 wt%; r is a rare earth element at least containing Nd; ga: 0.55-1.5 wt%; cu: 0.45-1 wt%; b: 0.85-0.94 wt%; al: 0.09-0.12 wt%; co: 0.5-2.5 wt%; fe: 64 to 69 wt%; n: one or more of Ti, Zr and Nb; when N contains Ti, the content of Ti is 0.2-0.25 wt%; when N contains Zr, the content of Zr is 0.25-0.35 wt%; when the N contains Nb, the content of Nb is 0.2-0.3 wt%; the percentage is the mass percentage of each component in the total mass of the R-T-B series permanent magnetic material;

or, the R-T-B series permanent magnetic material preferably comprises the following components in percentage by mass: r: 29.5 to 32.5 wt%; r is a rare earth element comprising Nd and Pr; pr: 5-10 wt%; ga: 0.55-1.5 wt%; cu: 0.45-1 wt%; b: 0.85-0.94 wt%; al: 0.09-0.12 wt%; co: 0.5-2.5 wt%; fe: 64 to 69 wt%; n: one or more of Ti, Zr and Nb; when N contains Ti, the content of Ti is 0.2-0.25 wt%; when N contains Zr, the content of Zr is 0.25-0.35 wt%; when the N contains Nb, the content of Nb is 0.2-0.3 wt%; the percentage is the mass percentage of each component in the total mass of the R-T-B series permanent magnetic material;

or, the R-T-B series permanent magnetic material preferably comprises the following components in percentage by mass: r: 29.5 to 32.5 wt%; r is a rare earth element comprising Nd and Pr; pr: 5-10 wt%; ga: 0.55-1.5 wt%; cu: 0.45-1 wt%; b: 0.85-0.94 wt%; al: 0.09-0.12 wt%; co: 0.5-2.5 wt%; fe: 64 to 69 wt%; ti: 0.2-0.25 wt%; the percentage is the mass percentage of each component in the total mass of the R-T-B series permanent magnetic material;

or, the R-T-B series permanent magnetic material preferably comprises the following components in percentage by mass: r: 29.5 to 32.5 wt%; r is a rare earth element at least containing Nd; ga: 0.55-1.5 wt%; cu: 0.45-1 wt%; b: 0.85-0.94 wt%; al: 0.09-0.12 wt%; co: 0.5-2.5 wt%; fe: 64 to 69 wt%; zr: 0.25-0.35 wt%; the percentage is the mass percentage of each component in the total mass of the R-T-B series permanent magnetic material;

or, the R-T-B series permanent magnetic material preferably comprises the following components in percentage by mass: r: 29.5 to 32.5 wt%; r is a rare earth element at least containing Nd; ga: 0.55-1.5 wt%; cu: 0.45-1 wt%; b: 0.85-0.94 wt%; al: 0.09-0.12 wt%; co: 0.5-2.5 wt%; fe: 64 to 69 wt%; nb: 0.2-0.3 wt%; the percentage is the mass percentage of each component in the total mass of the R-T-B series permanent magnet material.

10. An application of the R-T-B series permanent magnetic material as claimed in any one of claims 6 to 9 as an electronic component.