NEODYMIUM-IRON-BORON MAGNET MATERIAL, RAW MATERIAL COMPOSITION,PREPARATION METHOD THEREFOR AND USE THEREOF

Abstract

Disclosed are a neodymium-iron-boron magnet material, a raw material composition, a preparation method therefor and a use thereof. The raw material composition of the neodymium-iron-boron magnet material comprises the following components by mass percentage: 29.5-32.8% of R′, wherein R′ includes Pr and Nd, and Pr≥17.15%; Al≥0.5%; 0.90-1.2% of B; and 60-68% of Fe. The percentages are the mass percentages relative to the total mass of the raw material composition of the neodymium-iron-boron magnet material. Without adding a heavy rare earth element to the neodymium-iron-boron magnet material, the performance of the neodymium-iron-boron magnet material can still be significantly improved.

Claims

1. A raw material composition of neodymium-iron-boron magnet material, which comprises the following components by mass percentage: 29.5-32.8% of R′, R′ comprises Pr and Nd; wherein, Pr≥17.15%; Al≥0.5%; 0.90-1.2% of B; 60-68% of Fe; the percentage is the mass percentage relative to the total mass of the raw material composition of neodymium-iron-boron magnet material.

2. The raw material composition according to claim 1, wherein, the content of Pr is 17.15-30%; or, the ratio of Nd to the total mass of R′ is less than 0.5; or, the content of Nd is 15% or less; or, the content of Al is 0.5-3 wt. %; or, the content of B is 0.95-1.2%; or, the content of Fe is 60-67.515%.

3. The raw material composition according to claim 1, which comprises the following components by mass percentage: 29.5-32.8% of R′, wherein, R′ refers to rare earth elements, R′ comprises Pr and Nd; wherein, Pr≥17.15%; Al≥0.5%; Cu≤1.2%; 0.25-0.3% of Zr; 0.90-1.2% of B; 60-68% of Fe; the percentage is the mass percentage relative to the total mass of the raw material composition of neodymium-iron-boron magnet material.

4. The raw material composition according to claim 1, which comprises the following components by mass percentage: 29.5-32.8% of R′, wherein, R′ refers to rare earth elements, R′ comprises Pr and Nd; wherein, Pr≥17.15%; Al≥0.5%; Ga≤0.42%; Cu≤1.2%; 0.25-0.3% of Zr; 0.90-1.2% of B; 60-68% of Fe; the percentage is the mass percentage relative to the total mass of the raw material composition of neodymium-iron-boron magnet material.

5. A preparation method for neodymium-iron-boron magnet material, which employs the raw material composition according to claim 1; the preparation method comprises the following steps: subjecting the molten liquid of the raw material composition to melting and casting, hydrogen decrepitation, forming, sintering, and aging treatment.

6. A neodymium-iron-boron magnet material, which is prepared by the preparation method according to claim 5.

7. A neodymium-iron-boron magnet material, which comprises the following components by mass percentage: 29.4-32.8% of R′, R′ comprises Pr and Nd; wherein, Pr≥17.12%; Al≥0.48%; 0.90-1.2% of B; 60-68% of Fe; the percentage is the mass percentage relative to the total mass of the neodymium-iron-boron magnet material.

8. The neodymium-iron-boron magnet material according to claim 7, wherein, the content of Pr is 17.12-30%; or, the content of Nd is 15% or less; or, the content of Al is 0.48-3%; or, the content of B is 0.95-1.2%; or, the content of Fe is 59.9-67.7%.

9. A neodymium-iron-boron magnet material, wherein, in the intergranular triangular region of the neodymium-iron-boron magnet material, the ratio of the total mass of Pr and Al to the total mass of Nd and Al is ≤1.0; at the grain boundary of the neodymium-iron-boron magnet material, the ratio of the total mass of Pr and Al to the total mass of Nd and Al is ≥0.1.

10. A use of the neodymium-iron-boron magnet material according to claim 7 as an electronic component in a motor.

11. The raw material composition according to claim 1, wherein, R′ further comprises RH, RH refers to heavy rare earth elements, RH comprises one or more of Dy, Tb and Ho; the mass ratio of RH to R′ is less than 0.253; the content of RH is 0.5-2.7%.

12. The raw material composition according to claim 11, wherein, when RH comprises Tb, the content of Tb is 0.5-2 wt. %; or, when RH comprises Dy, the content of Dy is 0.5 wt. % or less; or, when RH comprises Ho, the content of Ho is 0.8-2%.

13. The raw material composition according to claim 1, wherein, the raw material composition of neodymium-iron-boron magnet material further comprises Cu; the content of Cu is 0.1-1.2%; or, the raw material composition of neodymium-iron-boron magnet material further comprises Ga; the content of Ga is 0.45 wt. % or less; or, the raw material composition of neodymium-iron-boron magnet material further comprises N; N comprises Zr, Nb, Hf or Ti; or, the raw material composition of neodymium-iron-boron magnet material further comprises Co; the content of Co is 0.5-3%; or, the raw material composition of neodymium-iron-boron magnet material further comprises O; the content of O is 0.13% or less; or, the raw material composition of neodymium-iron-boron magnet material further comprises one or more of Zn, Ag, In, Sn, V, Cr, Mo, Ta and W.

14. The raw material composition according to claim 3, wherein, the content of Pr is 17.15-30%; the content of Al is 0.5-3%; the content of Cu is 0.35-1.3%; R′ further comprises RH, RH refers to heavy rare earth elements, and the content of RH is 1-2.5%; the percentage is the mass percentage relative to the total mass of the raw material composition of neodymium-iron-boron magnet material.

15. The raw material composition according to claim 4, wherein, the content of Pr is 17.15-30%; the content of Al is 0.5-3%; the content of Cu is 0.35-1.3%; R′ further comprises RH, RH refers to heavy rare earth elements, and the content of RH is 1-2.5%, the percentage is the mass percentage relative to the total mass of the raw material composition of neodymium-iron-boron magnet material.

16. The preparation method for neodymium-iron-boron magnet material according to claim 5, wherein, after sintering and before the aging treatment, a grain boundary diffusion treatment is further carried out.

17. The neodymium-iron-boron magnet material according to claim 7, wherein, R′ further comprises RH, RH refers to heavy rare earth elements; RH comprises one or more of Dy, Tb and Ho; the mass ratio of RH to R′ is less than 0.253; the content of RH is 3% or less.

18. The neodymium-iron-boron magnet material according to claim 17, wherein, when RH comprises Tb, the content of Tb is 0.5-2.1 wt. %; or, when RH comprises Dy, the content of Dy is 0.51 wt. % or less; or, when RH comprises Ho, the content of Ho is 0.8-2%.

19. The neodymium-iron-boron magnet material according to claim 7, wherein, the neodymium-iron-boron magnet material further comprises Cu; the content of Cu is 1.2% or less; or, the neodymium-iron-boron magnet material further comprises Ga; the content of Ga is 0.42% or less; or, the neodymium-iron-boron magnet material further comprises N, and N comprises Zr, Nb, Hf or Ti; or, the neodymium-iron-boron magnet material further comprises Co; the content of Co is 0.5-3.5%; or, the neodymium-iron-boron magnet material further comprises 0, the content of 0 is 0.13% or less; or, the neodymium-iron-boron magnet material further comprises one or more of Zn, Ag, In, Sn, V, Cr, Mo, Ta and W.

20. The neodymium-iron-boron magnet material according to claim 7, wherein, in the intergranular triangular region of the neodymium-iron-boron magnet material, the ratio of the total mass of Pr and Al to the total mass of Nd and Al is ≤1.0; at the grain boundary of the neodymium-iron-boron magnet material, the ratio of the total mass of Pr and Al to the total mass of Nd and Al is ≥0.1.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0104] FIG. 1 is the element distribution diagram of the neodymium-iron-boron magnet material of Example 11.

[0105] FIG. 2 is the element distribution diagram at the grain boundary of the neodymium-iron-boron magnet material of Example 11, and symbol 1 in the figure shows the point taken at the grain boundary in quantitative analysis.

[0106] FIG. 3 is the element distribution diagram of the intergranular triangular region of the neodymium-iron-boron magnet material of Example 11, and symbol 1 in the figure is the point taken at the intergranular triangular region in quantitative analysis.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

[0107] The following examples further illustrate the present disclosure, but the present disclosure is not limited thereto. Experiment methods in which specific conditions are not indicated in the following embodiments are selected according to conventional methods and conditions, or according to the product specification. In the table below, wt. % refers to the mass percentage of the component in the raw material composition of the R-T-B permanent magnet material, and “/” indicates that the element has not been added. “Br” is the residual magnetic flux density and “Hcj” is the intrinsic coercivity.

[0108] The formulations for the raw material compositions of the neodymium-iron-boron magnet materials in each Examples 1-45 and Comparative Examples 46-49 are shown in Table 1 below.

TABLE-US-00001 TABLE 1 Formulations for the raw material compositions of the neodymium-iron-boron magnet materials (wt. %) No. Nd Pr Dy Tb Ho Al Cu Ga Zr Co Zn Mo B Fe 1 13.85 17.15 / / / 0.5 / / / / / / 0.985 67.515 2 12.85 18.15 / / / 0.6 / / / / / / 1 67.4 3 11.85 19.15 / / / 0.8 / / / / / / 0.985 67.215 4 11.65 20.15 / / / 0.9 / / / / / / 0.985 66.315 5 8.35 21.15 0.3 0.7 / 1 / / / / / / 0.985 67.515 6 6.85 24.15 0.5 0.5 / 1.2 / / / / / / 0.985 65.815 7 5.85 25.15 / 1 / 1.5 / / / / / / 0.985 65.515 8 3.85 26.5 / 1.5 / 1.8 / / / / / / 0.985 65.365 9 2.45 27.15 0.3 0 / 2 / / / / / / 0.985 65.115 10 1.5 30 / / / 2.2 / / / / / / 0.985 65.315 11 13.85 17.15 / / / 2.5 / / 0.25 / / / 0.985 65.265 12 12.85 18.15 / / / 3.0 / / / / / / 0.985 65.015 13 11.65 20.15 / / / 0.9 0.1 / / / / / 0.985 66.215 14 12.85 18.15 / / / 1 0.35 / / / / / 0.985 66.665 15 12.85 18.15 / / / 1.1 0.4 / / / / / 0.985 66.515 16 11.65 20.15 / / / 1.2 0.5 / / / / / 0.985 65.515 17 8.35 21.15 / / / 1.3 0.6 / / / / / 0.985 67.615 18 8.35 21.15 / / / 1.4 0.7 / / / / / 0.985 67.415 19 6.85 24.15 / / / 1.5 0.8 / / / / / 0.985 65.715 20 4.85 25.15 0.3 0.7 / 1.6 / 0.25 / / / / 0.985 66.165 21 4.85 25.15 0.3 0.7 / 1.6 / 0.35 / / / / 0.985 66.065 22 4.85 25.15 0.2 0.8 / 1.7 / 0.42 / / / / 0.985 65.895 23 4.85 25.15 0.2 0.8 / 1.7 / 0 0 1 / / 0.985 65.315 24 4.85 25.15 0.1 0.9 / 1.8 / 0 0.25 / / / 0.985 65.965 25 4.85 25.15 0.1 0.9 / 1.8 / 0 0.3 / / / 0.985 65.915 26 3.85 25.15 0.2 1 / 1.9 0.35 0.25 0 / / / 0.985 66.315 27 3.85 25.15 0.2 1 / 1.9 0.5 0.42 0 / / / 0.985 65.995 28 3.85 25.15 0.2 1.2 / 2 / 0.25 0.25 / / / 0.985 66.115 29 3.85 25.15 0.2 1.2 / 2 / 0.42 0.3 / / / 0.985 65.895 30 3.85 25.15 0.2 1.5 / 1 0.35 / 0.1 / / / 1.1 66.75 31 4.85 25.15 0.2 1.5 / 1 0.35 / 0.2 / / / 0.985 65.765 32 4.85 25.15 0.1 1.6 / 1.2 0.5 / 0.25 / / / 0.985 65.365 33 4.85 25.15 0.1 1.8 / 1.2 0.5 / 0.28 / / / 0.985 65.135 34 4.55 25.15 0.1 2 / 1.5 0.6 / 0.3 / / / 0.985 64.815 35 4.05 25.15 0.3 2 / 1.5 0.6 / 0.35 / / / 0.985 65.065 35.1 8.35 21.15 / 1 / 0.6 0.35 / 0.25 / / / 0.985 67.315 35.2 8.35 21.15 / 1 / 0.8 0.35 / 0.25 / / / 0.985 67.115 35.3 12.85 18.15 / / / 1.7 0.4 / 0.25 / / / 0.985 65.665 35.4 12.85 18.15 / / / 1.9 0.45 / 0.28 / / / 0.985 65.385 35.5 13.85 17.15 / / / 2.3 0.45 / 0.28 / / / 0.985 64.985 35.6 13.85 17.15 0   0 / 2.5 0.48 / 0.3 / / / 0.985 64.735 35.7 4.85 25.15 0.2 1.5 / 2.8 0.48 / 0.3 / / / 0.985 63.735 36 6.85 23.15 0.2 1 / 0.5 0.35 0.05 0.1 / / / 0.985 66.815 37 6.85 23.15 0.2 1 / 0.6 0.45 0.1 0.2 / / / 0.985 66.465 38 6.85 23.15 0.2 1.2 / 0.8 0.55 0.2 0.25 / / / 0.95 65.85 39 6.85 23.15 0.2 1.2 / 0.9 0.65 0.25 0.28 / / / 0.96 65.56 40 6.85 23.15 0.2 1.5 / 1 0.75 0.3 0.3 / / / 0.98 64.97 41 6.85 23.15 0.2 1.5 / 1.2 0.85 0.35 0.35 / / / 0.98 64.57 42 6.85 23.15 0.1 1.6 / 1.5 1 0.42 0.35 / / / 0.99 64.04 42.1 12.85 18.15 0.5 / 1.8 0.35 0.25 0.25 / / / 0.985 64.865 42.2 12.85 18.15 0.3 0.7 / 2.1 0.4 0.3 0.28 / / / 0.985 63.935 42.3 11.65 19.15 / 0.5 / 2.3 0.5 0.35 0.3 / / / 0.985 64.265 42.4 11.65 19.15 / 1 / 2.5 0.8 0.42 0.35 / / 0.985 63.145 42.5 8.35 21.15 / 1 / 2.7 0.9 0.35 0.25 / / / 0.985 64.315 42.6 8.35 21.15 / 1 / 2.9 1.1 0.35 0.28 / / / 0.985 63.885 43 6.85 23.15 0.1 1.6 1.0 1.5 1 0.42 0.35 3 / / 1 60.03 44 6.85 23.15 0.1 1.6 1.0 1.5 1 0.42 0.35 / 0.05 0.02 1.2 62.76 45 6.85 23.15 0.1 1.6 1.0 1.5 1 0.42 0.35 / 0.02 0.05 1 62.96 46 11.65 20.15 / / / 0.4 0.1 / / / / / 0.985 66.715 47 11.65 20.15 / / / 0.2 0.1 / / / / / 0.985 66.915 48 15.65 15.15 / / / 0.9 0.1 / / / / / 0.985 67.215 49 21.65 10.15 / / / 0.9 0.1 / / / / / 0.985 66.215

Example 1

[0109] The neodymium-iron-boron magnet material comprising Pr and Al was prepared as follows:

[0110] (1) Melting and casting: according to the formulation for the raw material compositions in each Example and Comparative Example shown in Table 1, the prepared raw material was put into a crucible made of alumina and vacuum melted in a high frequency vacuum induction melting furnace and in a vacuum of 5×10.sup.−2 Pa at a temperature of 1500° C. or less. After the vacuum melting, Ar gas was introduced into the melting furnace to make the pressure reach 55,000 Pa, then casting was carried out, and the quenched alloy was obtained at a cooling rate of 10.sup.2° C./sec to 10.sup.4° C./sec.

[0111] (2) Hydrogen decrepitation: the melting furnace in which the quench alloy was placed was evacuated at room temperature, and then hydrogen of 99.9% purity was introduced into the furnace for hydrogen decrepitation to maintain the hydrogen pressure at 0.15 MPa; after full hydrogen absorption, vacuuming was conducted while heating up to fully dehydrogenate; then cooling was carried out and the powder after hydrogen decrepitation was taken out.

[0112] (3) Micro pulverization process: the powder after hydrogen decrepitation was pulverized by jet mill for 3 hours under a nitrogen atmosphere with an oxidizing gas content of 150 ppm or less and under a pressure of 0.38 MPa in the pulverization chamber to obtain a fine powder. The oxidizing gas referred to oxygen or moisture.

[0113] (4) Zinc stearate was added to the powder from jet mill pulverization, and the addition amount of zinc stearate was 0.12% by weight of the mixed powder, and then mixed thoroughly with a V-mixer.

[0114] (5) Magnetic field forming process: the above-mentioned zinc stearate added powder was formed into a cube with a side length of 25 mm through primary forming by using a rectangular oriented magnetic field forming machine at an oriented magnetic field of 1.6 T and a forming pressure of 0.35 ton/cm.sup.2; and it was demagnetized in a magnetic field of 0.2 T after the primary forming. In order to prevent the formed body obtained after the primary forming from being exposed to air, it was sealed, and then a secondary forming machine (isostatic forming machine) was used to perform secondary forming at a pressure of 1.3 ton/cm.sup.2.

[0115] (6) Sintering process: each formed body was moved to the sintering furnace for sintering, which was held in vacuum of 5×10.sup.−3 Pa at 300° C. and 600° C. for 1 hour respectively; then, sintered at 1040° C. for 2 hours; then cooled to room temperature after the pressure reached 0.1 MPa by introducing Ar gas, to obtain sintered body.

[0116] (7) Aging treatment process: the sintered body was heat treated in high purity Ar gas at 600° C. for 3 hours and then heated to 550° C. at a heating rate of 3° C./min, it was cooled to room temperature before being taken out.

[0117] The parameters in the preparation processes of Examples 1-45 and Comparative Examples 46-49 were the same as Example 1 except that the formulations of the raw material compositions are different selected in the preparation processes.

Example 50

[0118] The neodymium-iron-boron magnet material of Example 50 was obtained by employing the Dy grain boundary diffusion method based on the raw material composition of Example 1, and the preparation process was as follows:

[0119] The No. 1 in Table 1 was first prepared according to the preparation of the sintered body of Example 1 to obtain a sintered body, followed by grain boundary diffusion, and then the aging treatment was carried out. Wherein, the process of aging treatment was the same as in Example 1, and the process of grain boundary diffusion was as follows:

[0120] The sintered body was processed into a magnet with a diameter of 20 mm and a sheet thickness of less than 3 mm in the direction of the magnetic field orientation, and after surface cleaning, the magnet was coated with a full spray using a raw material prepared with Dy fluoride, and the coated magnet was dried and the metal attached with Tb element was sputtered on the magnet surface in a high purity Ar atmosphere, diffusion heat treatment was carried out at the temperature of 850° C. for 24 hours. Cooled to room temperature.

Example 51

[0121] The neodymium-iron-boron magnet material of Example 51 was obtained by employing the Dy grain boundary diffusion method based on the raw material composition of Example 1, and the preparation process was as follows:

[0122] The No. 1 in Table 1 was first prepared according to the preparation of the sintered body of Example 1 to obtain a sintered body, followed by grain boundary diffusion, and then the aging treatment was carried out. Wherein, the process of aging treatment was the same as in Example 1, and the process of grain boundary diffusion was as follows:

[0123] The sintered body was processed into a magnet with a diameter of 20 mm and a sheet thickness of less than 7 mm in the direction of the magnetic field orientation, and after surface cleaning, the magnet was coated with a full spray using a raw material prepared with Tb fluoride, respectively, and the coated magnet was dried and the metal with attached Tb element was sputtered on the magnet surface in a high purity Ar atmosphere, diffusion heat treatment was carried out at the temperature of 850° C. for 24 hours. Cooled to room temperature.

Effect Examples

[0124] The magnetic properties and compositions of the neodymium-iron-boron magnet materials produced in each Example and Comparative Example were measured and the crystalline phase structure of the magnets was observed by FE-EPMA.

[0125] (1) Magnetic properties evaluation: The magnet materials were tested for magnetic properties by using the NIM-10000H BH bulk rare earth permanent magnet non-destructive measurement system from the National Institute of Metrology, China. The results of the magnetic properties testing were shown in Table 2 below.

TABLE-US-00002 TABLE 2 Testing results of the magnetic properties Absolute Absolute Absolute value of Hcj value of Hcj value of Hcj temperature temperature temperature Br Hcj coefficient coefficient coefficient No. (kGs) (kOe) at 80° C. at 150° C. at 180° C. 1 13.74 19.2 0.668 / / 2 13.61 19.95 0.647 / / 3 13.44 21.19 0.609 / / 4 13.10 22.32 0.596 / / 5 13.04 25.57 / 0.519 / 6 12.38 27.73 / 0.498 / 7 11.87 30.06 / / 0.439 8 11.61 32.02 / / 0.429 9 11.17 35.5 / / 0.385 10 11.46 29.95 / 0.488 / 11 11.76 27.55 / 0.492 / 12 11.05 28.5 / 0.499 / 13 13.11 22.53 0.591 / / 14 13.26 22.76 0.589 / / 15 13.16 23.37 0.576 / / 16 12.81 24.97 / 0.523 / 17 13.24 24.96 / 0.526 / 18 13.13 25.03 / 0.519 / 19 12.6 26.5 / 0.511 / 20 12.1 29.9 / / 0.446 21 12.05 30.61 / / 0.444 22 11.71 30.1 / / 0.443 23 11.91 28.87 / 0.495 / 24 11.7 28.64 / 0.498 / 25 11.5 29.02 / 0.493 / 26 11.58 32.7 / / 0.439 27 11.38 33.5 / / 0.435 28 11.3 32.5 / / 0.431 29 11.28 33.75 / / 0.426 30 12.36 31.29 / / 0.448 31 12.19 31.79 / / 0.449 32 12.19 30.72 / / 0.438 33 11.76 32.88 / / 0.431 34 11.33 34.75 / / 0.421 35 11.23 34.1 / / 0.425 35.1 13.15 24.96 / 0.526 / 35.2 12.97 25.95 / 0.513 / 35.3 12.29 25.14 / 0.519 / 35.4 12.08 26.14 / 0.508 / 35.5 11.7 27.85 / 0.492 / 35.6 11.57 28.42 / 0.481 / 35.7 10.85 35.1 / / 0.388 36 13.22 25.97 / / / 37 13.09 27.11 / 0.517 / 38 12.58 29.81 / 0.488 / 39 12.10 33.14 / / 0.429 40 12.0 33.35 / / 0.424 41 11.8 33.28 / / 0.427 42 11.6 33.6 / / 0.420 42.1 12 28..24 / 0.512 / 42.2 11.38 31.2 / / 0.441 42.3 11.44 32.45 / / 0.438 42.4 10.5 34.5 / / 0.424 42.5 10.42 36.2 / / 0.375 42.6 10.22 37.2 / / 0.364 43 10.6 36 / / 0.380 44 10.52 36.5 / / 0.372 45 10.48 36.3 / / 0.376 46 12.48 25 / 0.517 / 47 12.60 23 0.601 / / 48 12.37 21.01 0.623 / / 49 12.24 20.2 0.642 / / 50 13.56 25.5 / 0.514 / 51 13.53 30.1 / / 0.449

[0126] (2) Component determination: each component was determined by using a high frequency inductively coupled plasma emission spectrometer (ICP-OES). The component determination results of the neodymium-iron-boron magnet materials in each Example and Comparative Example were shown in Table 3 below.

TABLE-US-00003 TABLE 3 Testing results of compositions of the neodymium-iron-boron magnet materials (wt. %) No. Nd Pr Dy Tb Ho Al Cu Ga Zr Co Zn Mo B Fe 1 13.82 17.13 0 0 / 0.48 0 0 0 / / / 0.983 67.587 2 12.82 18.13 0 0 / 0.61 0 0 0 / / / 0.99 67.45 3 11.85 19.12 0 0 / 0.82 0 0 0 / / / 0.986 67.224 4 11.64 20.14 0 0 / 0.91 0 0 0 / / / 0.983 66.327 5 8.34 21.14 0.29 0.71 / 1.01 0 0 0 / / / 0.984 67.526 6 6.86 24.16 0.49 0.51 / 1.22 0 0 0 / / / 0.981 65.779 7 5.84 25.12 / 1.02 / 1.51 0 0 0 / / / 0.986 65.524 8 3.86 26.52 / 1.52 / 1.79 0 0 0 / / / 0.983 65.327 9 2.45 27.15 0.29 2.02 / 2.01 0 0 0 / / / 0.984 65.096 10 1.5 30 / / / 2.21 0 0 0 / / / 0.981 65.309 11 13.84 17.14 / / / 2.52 0 0 0.25 / / / 0.986 65.264 12 12.89 18.16 / / / 2.98 0 0 0 / / / 0.983 64.987 13 11.55 20.05 / / / 0.92 0.11 0 0 / / / 0.984 66.386 14 12.83 18.13 / / / 1.02 0.34 0 0 / / / 0.981 66.699 15 12.82 18.16 / / / 1.09 0.41 0 0 / / / 0.986 66.534 16 11.63 20.13 / / / 1.23 0.51 0 0 / / / 0.986 65.514 17 8.34 21.13 / / / 1.31 0.63 0 0 / / / 0.983 67.607 18 8.33 21.12 / / / 1.42 0.72 0 0 / / / 0.984 67.426 19 6.83 24.16 / / / 1.53 0.81 0 0 / / / 0.981 65.689 20 4.82 25.17 0.31 0.69 / 1.62 0 0.23 0 / / / 0.986 66.174 21 4.83 25.14 0.32 0.71 / 1.63 0 0.34 0 / / / 0.983 66.047 22 4.84 25.12 0.19 0.83 / 1.73 0 0.41 0 / / / 0.984 65.896 23 4.83 25.13 0.23 0.81 / 1.72 0 0 0 1 / 0.981 65.299 24 4.86 25.14 0.12 0.88 / 1.82 0 0 0.25 / / / 0.986 65.944 25 4.87 25.13 0.13 0.9 / 1.81 0 0 0.3 / / / 0.983 65.877 26 3.89 25.16 0.21 1 / 1.92 0.35 0.25 0 / / / 0.984 66.236 27 3.86 25.12 0.19 1 / 1.91 0.5 0.42 0 / / / 0.981 66.019 28 3.84 25.13 0.23 1.2 / 2.02 0 0.25 0.25 / / / 0.986 66.094 29 3.84 25.14 0.22 1.2 / 2.03 0 0.42 0.3 / / / 0.983 65.867 30 3.83 25.13 0.21 1.5 / 1.03 0.35 0 0.11 / / / 1.11 66.73 31 4.86 25.16 0.22 1.5 / 1.04 0.35 0 0.22 / / / 0.986 65.664 32 4.87 25.12 0.11 1.6 / 1.23 0.5 0 0.24 / / / 0.983 65.347 33 4.84 25.13 0.11 1.8 / 1.21 0.5 0 0.28 / / / 0.984 65.146 34 4.52 25.14 0.12 2.01 / 1.53 0.6 0 0.3 / / / 0.981 64.799 35 4.03 25.13 0.31 2.02 / 1.49 0.6 0 0.35 / / / 0.986 65.084 35.1 8.35 21.15 / 1 / 0.6 0.35 / 0.25 / / / 0.985 67.315 35.2 8.35 21.15 / 1 / 0.8 0.35 / 0.25 / / / 0.985 67.115 35.3 12.85 18.15 / / / 1.7 0.4 / 0.25 / / / 0.985 65.665 35.4 12.85 18.15 / / / 1.9 0.45 / 0.28 / / / 0.985 65.385 35.5 13.85 17.15 / / / 2.3 0.45 / 0.28 / / / 0.985 64.985 36 6.83 23.11 0.22 1.03 / 0.48 0.35 0.05 0.1 / / / 0.983 66.847 37 6.82 23.12 0.21 1.04 / 0.58 0.45 0.1 0.2 / / / 0.984 66.496 38 6.83 23.13 0.22 1.21 / 0.83 0.55 0.2 0.25 / / / 0.951 65.829 39 6.84 23.13 0.21 1.21 / 0.92 0.65 0.25 0.28 / / / 0.962 65.548 40 6.84 23.15 0.22 1.51 / 1.02 0.75 0.31 0.32 / / / 0.983 64.897 41 6.83 23.11 0.21 1.51 / 1.21 0.85 0.36 0.37 / / / 0.984 64.566 42 6.84 23.12 0.11 1.59 / 1.51 1.02 0.44 0.36 / / / 0.981 64.029 42.1 12.84 18.14 0.48 / / 1.81 0.34 0.251 0.24 / / / 0.984 64.915 42.2 12.83 18.16 0.31 0.71 / 2.12 0.41 0.31 0.27 / / / 0.984 63.896 42.3 11.66 19.14 / 0.51 / 2.31 0.51 0.34 0.31 / / / 0.986 64.234 42.4 11.64 19.14 / 1.02 / 2.52 0.81 0.41 0.34 / / 0.984 63.136 42.5 8.36 21.16 / 1.03 / 2.71 0.91 0.34 0.24 / / / 0.984 64.266 42.6 8.34 21.14 / 1.01 / 2.91 1.11 0.34 0.27 / / / 0.984 63.896 43 6.86 23.13 0.12 1.58  0.99 1.52 1.03 0.43 0.38 3.03 / / 0.998 59.932 44 6.86 23.13 0.13 1.58 1.0 1.51 1.04 0.41 0.37 / 0.04 0.02 1.11 62.8 45 6.86 23.11 0.12 1.59 1.0 1.52 1.03 0.41 0.36 / 0.03 0.06 1.03 62.88 46 11.64 20.14 / / / 0.41 0.13 / / / / / 0.986 66.694 47 11.63 20.13 / / / 0.22 0.12 / / / / / 0.983 66.917 48 15.63 15.14 / / / 0.90 0.13 / / / / / 0.984 67.216 49 21.62 10.14 / / / 0.89 0.12 / / / / / 0.981 66.249 50 13.81 17.12 0.51 0 / 0.49 0 0 0 / / / 0.982 67.088 51 13.82 17.13 0 0.56 / 0.48 0 0 0 / / / 0.981 67.029

[0127] (3) FE-EPMA inspection: The neodymium-iron-boron magnet material of Example 11 was tested by the Field Emission Electron Probe Micro-Analyzer (FE-EPMA) (Japan Electronics Company (JEOL), 8530F). The elements of Pr, Nd, Al, Zr and O in the magnet material were determined, and the elements at the grain boundary and the intergranular triangular region were quantitatively analyzed. Wherein: the grain boundary refer to the boundary between two grains, and the intergranular triangle region refer to the gap formed by three and more grains.

[0128] It can be seen from FIG. 1 that Pr and Nd elements were mainly distributed in the main phase, part of the rare earth was also present at the grain boundary, element Al was distributed in the main phase, and element Zr was distributed at the grain boundaries. As shown in FIG. 2, which is the element distribution diagram at the grain boundary of the neodymium-iron-boron magnet material of Example 11, the point marked with 1 in FIG. 2 was taken for quantitative analysis of the elements at the grain boundaries, the results were shown in Table 4 below:

TABLE-US-00004 TABLE 4 Pr Nd Al Zr O Fe (wt. %) (wt. %) (wt. %) (wt. %) (wt. %) (wt. %) 45.5 10.5 0.19 0.059 0.80 Balance

[0129] From the above data, it can be seen that Pr and Nd were present at the grain boundary in the form of rare earth rich phases and oxides, which were respectively a-Pr and a-Nd, Pr.sub.2O.sub.3, Nd.sub.2O.sub.3 and NdO, and Al occupied a certain content of about 0.2 wt. % at the grain boundary in addition to the main phase, for example 0.19 wt. % in this example. Zr as a high melting point element was diffusely distributed throughout the region.

[0130] As shown in FIG. 3, which is the element distribution diagram of the intergranular triangular region, the point marked with 1 in FIG. 3 was taken for quantitative analysis of the elements at the intergranular triangular region, the results were shown in Table 5 below:

TABLE-US-00005 TABLE 5 Pr Nd Al Zr O Fe (wt. %) (wt. %) (wt. %) (wt. %) (wt. %) (wt. %) 32.8 42.3 1.38 0.079 1.2 Balance

[0131] It can be seen from Table 5 that Pr and Nd elements were distributed in the intergranular triangular region. In the formulation of this example, it is clearly found that the content of Pr is obviously lower than that of Nd in the intergranular triangular region, although rare earths are partially enriched here, the enrichment degree of Pr is less than that of Nd, which is one of the reasons why high Pr and Al work together to improve the coercivity. At the same time, there is a partial distribution of O and Zr therein.