Sintered neodymium-iron-boron magnet material, method for producing same and use thereof

Abstract

The application discloses a sintered Nd-Fe-B magnet material and a preparation method and application thereof. The preparation method comprises the following steps: smelting, casting, crushing, forming, sintering and aging treatment of raw materials; the casting adopts a rapid solidification casting method; the rotating speed of copper is 2-4 m / s, and the cooling water temperature is 5-15 DEG C; the raw materials of the sintered Nd-Fe-B magnet material comprise the following components: B, 0.88-0.93%; X, 0.05-0.45%, X is Zr and / or Ti; Ga, 0.3-0.7%; Y, 28-31%, Y is Pr and / or Nd; Z, 0-2%, Z is Dy and / or Tb; Cu, 0.2-1%; Co, 0-1%; Al, 0-1%; and Fe, the balance. The sintered Nd-Fe-B magnet material has high mechanical strength, and the yield rate during machining can be reduced, so that the machining cost is reduced.

Description

Technical Field

[0001] This invention relates to a sintered NdFeB magnet material, its preparation method, and its application. Background Technology

[0002] With the vigorous promotion of new energy vehicles worldwide in recent years, the demand for lithium batteries, permanent magnet synchronous motors, and other related products has also increased dramatically. Among these, sintered neodymium iron boron magnets, as the undisputed "king of magnets," play a very important role in permanent magnet synchronous motors.

[0003] However, sintered NdFeB magnet materials have poor mechanical properties, making them prone to fracture during machining and resulting in a high defect rate, especially for the processing of small products where the yield is even lower. Therefore, improving the mechanical properties of sintered NdFeB magnet materials and increasing their mechanical strength can effectively reduce the high costs caused by the high defect rate during machining.

[0004] In fact, sintered NdFeB magnets are intrinsically brittle materials, with a typical microstructure consisting of a NdFeB-rich grain boundary phase enclosing a tetragonal main phase. The tetragonal phase is a typical intermetallic compound with a very complex crystal structure, lacking slip systems and therefore lacking plasticity, but possessing high strength and hardness. The NdFeB-rich phase, on the other hand, has some plasticity, but its strength and hardness are far lower than the brittle tetragonal phase. This structural characteristic means that when NdFeB fractures, cracks inevitably propagate along the weaker NdFeB-rich phase, resulting in intergranular fracture and consequently, poor mechanical strength in sintered NdFeB magnets. Therefore, if cracks could propagate within the stronger tetragonal phase during fracture, the mechanical strength of sintered NdFeB magnets could be significantly improved.

[0005] However, although numerous methods exist for improving the mechanical strength of sintered NdFeB magnets, none have fundamentally addressed the underlying cause of their high brittleness. In fact, while various alloying elements can improve the mechanical strength of NdFeB magnets to some extent, they are unlikely to alter crack propagation behavior, thus failing to fundamentally improve the mechanical strength of sintered NdFeB magnets.

[0006] Therefore, developing a method to fundamentally improve the mechanical strength of sintered NdFeB magnet materials, reduce the defect rate of sintered NdFeB magnet materials during machining, and reduce the processing cost of sintered NdFeB magnet materials has become an urgent problem to be solved. Summary of the Invention

[0007] The technical problem to be solved by this invention is to overcome the low mechanical strength and high defect rate during machining of sintered NdFeB magnet materials in the prior art, and to provide a NdFeB magnet material, its preparation method, and its application. The sintered NdFeB magnet material of this invention has high mechanical strength, which can reduce the defect rate during machining, thereby reducing the processing cost of sintered NdFeB magnet materials.

[0008] The present invention mainly solves the above-mentioned technical problems through the following technical means.

[0009] This invention provides a method for preparing sintered NdFeB magnet material, which includes the following steps: sequentially subjecting a mixture of raw materials for sintered NdFeB magnet material to melting, casting, crushing, molding, sintering and aging treatment to obtain sintered NdFeB magnet material;

[0010] The casting process employs a rapid solidification casting method; in this method, the rotation speed of the copper roller is 2 m / s to 4 m / s, and the cooling water temperature is 5℃ to 15℃.

[0011] The sintered NdFeB magnet material comprises the following components in its raw materials:

[0012] B, 0.88%–0.93%;

[0013] X, 0.05% to 0.45%, wherein X is one or both of Zr and Ti;

[0014] Ga, 0.3%–0.7%;

[0015] Y, 28%–31%, wherein Y is one or both of Pr and Nd;

[0016] Z, 0% to 2%, wherein Z is one or both of Dy and Tb;

[0017] Cu, 0.2%–1%;

[0018] Co, 0%–1%;

[0019] Al, 0%–1%;

[0020] Fe, balance;

[0021] Wherein, % refers to the mass percentage of each component relative to the total mass of all raw materials in the sintered NdFeB magnet material; the sum of the mass percentages of each component is 100%.

[0022] In this invention, the thickness of the rapidly solidified sheet in the rapid solidification casting method is preferably 0.1 mm to 0.25 mm; for example, 0.1 mm to 0.2 mm.

[0023] In this invention, the rotational speed of the copper roller in the rapid solidification casting method is preferably 2.5 m / s to 3.5 m / s, for example, 2.5 m / s.

[0024] In this invention, the cooling water temperature in the rapid solidification casting method is preferably 5°C to 10°C, for example, 8°C.

[0025] In this invention, the content of B is preferably 0.9% to 0.92%, for example 0.91% to 0.92%; % refers to the mass percentage of B relative to the total mass of all raw materials of the sintered NdFeB magnet material.

[0026] In this invention, the content of X is preferably 0.15% to 0.35%, for example 0.2% to 0.35%; % refers to the mass percentage of X in the total mass of the sintered NdFeB magnet material raw material.

[0027] In this invention, the content of Ga is preferably 0.4% to 0.6%, for example 0.5% to 0.6%; % refers to the mass percentage of Ga in the total mass of all raw materials of the sintered NdFeB magnet material.

[0028] In this invention, the content of Y is preferably 29.8% to 30.5%; % refers to the mass percentage of Y relative to the total mass of all raw materials in the sintered NdFeB magnet material. Preferably, Y is Nd.

[0029] In this invention, the content of Co is preferably 0.3% to 0.5%; % refers to the mass percentage of Co in the total mass of all raw materials of the sintered NdFeB magnet material.

[0030] In this invention, the Cu content is preferably 0.5% to 0.7%; % refers to the mass percentage of Cu in the total mass of all raw materials of the sintered NdFeB magnet material.

[0031] In this invention, the content of Al is preferably 0-0.5%; % refers to the mass percentage of Al in the total mass of all raw materials of the sintered NdFeB magnet material.

[0032] In this invention, the Fe content is 61.92% to 70.57%; preferably 65.93% to 67.45%; % refers to the mass percentage of Fe in the total mass of all raw materials of the sintered NdFeB magnet material.

[0033] In a preferred embodiment of the present invention, the sintered NdFeB magnet material comprises the following components: 0.91% B, 0.2% Ti, 0.5% Ga, 29.8% Nd, 0.5% Co, 0.5% Cu, 0.5% Al, and 67.09% Fe; wherein % refers to the mass percentage of each component relative to the total mass of the raw materials of the sintered NdFeB magnet material (the sum of the mass percentages of each component is 100%).

[0034] In a preferred embodiment of the present invention, the sintered NdFeB magnet material comprises the following components: 0.92% B, 0.35% Zr, 0.6% Ga, 30.5% Nd, 0.3% Co, 0.7% Cu, and 66.63% Fe; wherein % refers to the mass percentage of each component relative to the total mass of the raw materials of the sintered NdFeB magnet material (the sum of the mass percentages of each component is 100%).

[0035] Preferably, the raw materials of the sintered NdFeB magnet material are composed of the following components: B, X, Ga, Y, Z, Cu, Co, Al, and Fe.

[0036] In this invention, the smelting process can be conventional in the field.

[0037] The vacuum degree of the melting process is, for example, 5 × 10⁻⁶. -2 Pa.

[0038] The melting temperature is, for example, below 1550°C, such as 1540°C.

[0039] In this invention, the casting temperature can be 1390–1460°C, for example 1410°C.

[0040] In this invention, the pulverization process can be conventional in the field.

[0041] The pulverization generally includes hydrogen pulverization and air jet milling.

[0042] The hydrogen crushing process can generally involve sequential hydrogen absorption, dehydrogenation, and cooling.

[0043] The hydrogen absorption can be carried out under a hydrogen pressure of 0.085 MPa.

[0044] The dehydrogenation can be carried out under conditions of simultaneous vacuuming and heating. The dehydrogenation temperature can be 480–520°C, for example, 500°C.

[0045] In this invention, the gas atmosphere during the air jet milling process can be such that the content of oxidizing gas is below 100 ppm, where the content of oxidizing gas refers to the content of oxygen and / or moisture.

[0046] After the air jet milling process, a lubricant, such as zinc stearate, may generally be added. The amount of lubricant added may be 0.05% to 0.15% of the mass of the powder obtained after air jet milling, for example, 0.12%.

[0047] In this invention, the molding process can be performed using a magnetic field molding method.

[0048] The magnetic field shaping is performed, for example, under a magnetic field strength of 1.8 to 2.5 T.

[0049] In this invention, the sintering process can be conventional in the field.

[0050] The vacuum degree of the sintering is, for example, 5 × 10⁻⁶. -3 Pa.

[0051] The sintering temperature can be 1000-1100℃, for example 1080℃.

[0052] The sintering time can be 4 to 8 hours, for example, 6 hours.

[0053] In this invention, the aging treatment includes a two-stage aging treatment; wherein, the first-stage aging temperature can be 880℃~920℃, for example 880℃; and the second-stage aging temperature can be 440℃~520℃, for example 490℃.

[0054] In this invention, the time for the first-level aging process is preferably 2 to 4 hours, for example, 3 hours.

[0055] In this invention, the second-level aging process is preferably 1 to 4 hours, for example, 3 hours.

[0056] The present invention also provides a sintered NdFeB magnet material, which is prepared by the above-described preparation method.

[0057] This invention also provides a sintered NdFeB magnet material, the raw materials of which include the following components:

[0058] B, 0.88%–0.93%;

[0059] X, 0.05% to 0.45%, wherein X is one or both of Zr and Ti;

[0060] Ga, 0.3%–0.7%;

[0061] Y, 28%–31%, wherein Y is one or both of Pr and Nd;

[0062] Z, 0% to 2%, wherein Z is one or both of Dy and Tb;

[0063] Cu, 0.2%–1%;

[0064] Co, 0%–1%;

[0065] Al, 0%–1%;

[0066] Fe, balance;

[0067] Wherein, % refers to the mass percentage of each component relative to the total mass of all raw materials of the sintered NdFeB magnet material; the sum of the mass percentages of each component is 100%; preferably, the content of each component in the raw materials is the same as that described in the preparation method of the sintered NdFeB magnet material.

[0068] In this invention, the sintered NdFeB magnet material may include Nd-rich phase, tetragonal phase, Fe-rich phase, and XB2 phase.

[0069] In this invention, the Fe content in the Fe-rich phase is preferably 35% to 55% by mass; for example, the Fe content by mass is about 44%.

[0070] In this invention, the content of Y in the Fe-rich phase is preferably 40% to 60% by mass; for example, the content of Nd is about 50% by mass.

[0071] In this invention, the Fe-rich phase preferably also includes Ga, Al and Cu, or metallic elements such as Ga and Cu; for example, the content of Ga by mass percentage is about 4.5%, and the content of Cu by mass percentage is about 0.5%.

[0072] In this invention, the sintered NdFeB magnet material may undergo an oxidation reaction during the preparation process, and the Fe-rich phase may also include O element with a content of 0% to 2% by mass; for example, the content of O by mass is about 1%.

[0073] In this invention, the area ratio of the Nd-rich phase can be 5% to 25%, for example, 6%.

[0074] In this invention, the area ratio of the tetragonal phase can be 70% to 93%, for example, 90%.

[0075] In this invention, the area ratio of the Fe-rich phase can be 2% to 25%, for example, 4%.

[0076] In this invention, the XB2 phase is preferably distributed as a diffuse small dot phase in the neodymium-rich phase and / or at the edge of the tetragonal phase.

[0077] In this invention, the area ratio generally refers to the area occupied by different constituent phases in the vertical orientation plane of the sintered NdFeB magnet material during BSE testing.

[0078] In this invention, the sintered NdFeB magnet material preferably has lattice defects on the surface of the tetragonal phase grains.

[0079] The present invention also provides an application of the above-mentioned sintered NdFeB magnet material as an electronic component.

[0080] Without violating common sense in the field, the above-mentioned preferred conditions can be combined arbitrarily to obtain various preferred embodiments of the present invention.

[0081] The reagents and raw materials used in this invention are all commercially available.

[0082] The significant advantages of this invention are as follows: By controlling the boron (B) content in the raw materials of sintered NdFeB magnets and the rapid solidification casting process during the preparation of sintered NdFeB magnets, lattice defects are introduced on the surface of the tetragonal phase grains in the sintered NdFeB magnet material. The principle is that by controlling the B content, the magnet is in a B-deficient state, with only enough B to form the tetragonal phase, without any excess B. Furthermore, by controlling the rapid solidification process, Ti and / or Zr are uniformly distributed atomically in the Nd-rich phase of the rapidly solidified sheet. Utilizing the chemical affinity of Ti and / or Zr for B, Ti and / or Zr consume the B elements in the Nd-rich phase and on the surface of the nearby tetragonal phase grains during subsequent sintering. Since the B content is controlled, there is no excess B in the Nd-rich phase; therefore, Ti and / or Zr will primarily consume the B elements on the surface of the tetragonal phase grains. In other words, the above-mentioned limiting conditions cause TiB2 and / or ZrB2 to cause certain damage to the lattice integrity of the tetragonal phase grain surface during formation, thereby introducing lattice defects such as vacancies on the surface of the tetragonal phase grain.

[0083] The role of introducing lattice defects is that when the material is under stress, stress concentration occurs at the lattice defects on the surface of the tetragonal phase, causing microcracks to form in the tetragonal phase rather than the Nd-rich phase. Ga is introduced to enable microcracks to continue propagating within the tetragonal grains after formation. Ga significantly improves the fluidity and wettability of the Nd-rich phase in sintered NdFeB magnet materials, greatly enhancing the bonding force between the Nd-rich and tetragonal phases and preventing microcracks from reverting to the Nd-rich phase during subsequent propagation.

[0084] The design of this invention forces cracks in sintered NdFeB magnets to propagate within the higher mechanical strength tetragonal grains during fracture, changing the fracture mode from the common intergranular fracture to transgranular fracture, thereby significantly improving the mechanical strength of the sintered NdFeB magnets. Through its ingenious design, this invention fundamentally enhances the mechanical strength of sintered NdFeB magnets, reduces the defect rate during machining, and thus lowers the processing costs. Attached Figure Description

[0085] Figure 1 The image shows the BSE (backscattered electron image) and the corresponding Ti element scan of the rapid-condensing tablet in Example 1.

[0086] Figure 2 The image shows the BSE diagram of the sintered NdFeB magnet material in Example 1; where A is the tetragonal phase, B is the Nd-rich phase, C is the Fe-rich phase, and D is the TiB2 phase distributed at the edges of the Nd-rich phase and the tetragonal phase.

[0087] Figure 3 This is a SEM (scanning electron microscope) image of the fracture surface of the sintered NdFeB magnet material in Example 1.

[0088] Figure 4 The image shows the BSE plot and corresponding Zr elemental scan plot of the fast-curing tablets in Example 2.

[0089] Figure 5 The image shows the fracture surface SEM image of the sintered NdFeB magnet material in Comparative Example 1. Detailed Implementation

[0090] The present invention is further illustrated below by way of embodiments, but the invention is not limited to the scope of the embodiments described herein. Experimental methods in the following embodiments that do not specify specific conditions were performed according to conventional methods and conditions, or as selected according to the product instructions.

[0091] Unless otherwise specified, the BSE diagram and EPMA below were obtained using a JXA-8530F from Nippon Electronics.

[0092] Unless otherwise specified, the SEM images below were obtained using Hitachi's S-4800II.

[0093] Example 1:

[0094] (1) Ingredients: 0.91% B, 0.2% Ti, 0.5% Ga, 29.8% Nd, 0.5% Co, 0.5% Cu, 0.5% Al and 67.09% Fe; % refers to the mass percentage of each component relative to the total mass of the sintered NdFeB magnet material.

[0095] (2) Melting: The raw material mixture of the sintered NdFeB magnet material from step (1) is placed in a vacuum of 5×10⁻⁶. - 2 In a high-frequency vacuum induction melting furnace, Pa was melted into a liquid at 1540°C.

[0096] (3) Casting: The molten liquid obtained from melting is cast using the rapid solidification casting method to obtain rapid solidification sheets. In the rapid solidification casting method, the cooling water temperature is 8℃, the copper roller rotation speed is 2.5m / s, and the thickness of the obtained rapid solidification sheets is 0.1mm~0.2mm.

[0097] (4) Crushing: Hydrogen crushing and air jet milling are performed in sequence.

[0098] The hydrogen crushing process involves hydrogen absorption, dehydrogenation, and cooling. Hydrogen absorption is carried out under a hydrogen pressure of 0.085 MPa. Dehydrogenation is performed under conditions of simultaneous vacuum and heating, with a dehydrogenation temperature of 500℃.

[0099] The air jet milling was performed under conditions where the oxidizing gas content was below 100 ppm, resulting in a particle size of 4.2 μm. Oxidizing gases refer to oxygen or moisture content. The grinding chamber pressure was 0.68 MPa. After milling, zinc stearate, a lubricant, was added at 0.12% of the weight of the mixed powder.

[0100] (5) Magnetic field shaping: carried out under a magnetic field strength of 1.8 to 2.5 T and a nitrogen atmosphere.

[0101] (6) Sintering: at 5×10 -3 Under vacuum conditions, the material is sintered and cooled. Sintering is carried out at 1080℃ for 6 hours; before cooling, Ar gas can be introduced to achieve a pressure of 0.05MPa.

[0102] (7) Aging treatment: The first aging temperature is 880℃ and the time is 3h; the second aging temperature is 490℃ and the time is 3h, to obtain sintered NdFeB magnet material.

[0103] Example 2:

[0104] (1) Ingredients: 0.92% B, 0.35% Zr, 0.6% Ga, 30.5% Nd, 0.3% Co, 0.7% Cu and 66.63% Fe; % refers to the mass percentage of each component relative to the total mass of the sintered NdFeB magnet material.

[0105] The remaining steps are carried out according to steps (2) to (7) of Example 1 to obtain sintered NdFeB magnet material.

[0106] Comparative Example 1:

[0107] (1) Ingredients: 1% B, 0.2% Ti, 0.5% Ga, 29.8% Nd, 0.5% Co, 0.5% Cu, 0.5% Al and 67% Fe; % refers to the mass percentage of each component relative to the total mass of the sintered NdFeB magnet material.

[0108] The remaining steps are carried out according to steps (2) to (7) of Example 1 to obtain sintered NdFeB magnet material.

[0109] Comparative Example 2:

[0110] (1) Ingredients: 0.91% B, 0.2% Ti, 0.5% Ga, 29.8% Nd, 0.5% Co, 0.5% Cu, 0.5% Al and 67.09% Fe; % refers to the mass percentage of each component relative to the total mass of the sintered NdFeB magnet material.

[0111] (2) Melt according to step (2) of Example 1.

[0112] (3) Casting: The molten liquid obtained from melting is cast using the rapid solidification casting method to obtain rapid solidification sheets. In the rapid solidification casting method, the cooling water temperature is 25℃, the copper roller rotation speed is 1m / s, and the thickness of the obtained rapid solidification sheets is 0.3mm~0.35mm.

[0113] The remaining steps are carried out according to steps (4) to (7) of Example 1 to obtain sintered NdFeB magnet material.

[0114] Example 1:

[0115] The BSE diagram and Ti elemental distribution diagram of the quick-setting tablets from Example 1 are shown below. Figure 1 As shown. From Figure 1 It can be seen that in the quick-setting tablets of Example 1, Ti elements are mainly distributed in the Nd-rich phase in atomic form and do not combine with other elements to form compounds.

[0116] The BSE diagram of the sintered NdFeB magnet material from Example 1 is shown below. Figure 2 As shown. From Figure 2 It can be seen that the sintered NdFeB magnet material of Example 1 has four phases: A is the tetragonal phase, B is the Nd-rich phase, C is the Fe-rich phase, and D is the TiB2 phase distributed on the edges of the Nd-rich phase and the tetragonal phase.

[0117] Semi-quantitative analysis of the components in the Fe-rich phase was performed using EPMA. The Fe content was approximately 44% by mass, the Nd content was approximately 50% by mass, the Ga content was approximately 4.5% by mass, the Cu content was approximately 0.5% by mass, and the O content was approximately 1% by mass.

[0118] The area proportion of each phase was analyzed using ImageJ software. The Nd-rich phase accounted for 6% of the area, the tetragonal phase accounted for 90%, the Fe-rich phase accounted for 4%, and the XB2 phase was distributed as a diffuse small dot phase in the Nd-rich phase and / or at the edge of the tetragonal phase.

[0119] The SEM image of the fracture surface of the sintered NdFeB magnet material from Example 1 is shown below. Figure 3 As shown. From Figure 3 It can be seen that when the sintered NdFeB magnet material of Example 1 fractures, the cracks mainly propagate within the tetragonal phase, and the fracture mode is mainly transgranular fracture.

[0120] Example 2

[0121] The BSE diagram and Zr elemental distribution diagram of the quick-setting tablets from Example 2 are shown below. Figure 4 As shown. From Figure 4 It can be seen that in the quick-setting tablets of Example 2, Zr elements are mainly distributed in the Nd-rich phase in atomic form and do not combine with other elements to form compounds.

[0122] Comparison of effects 1

[0123] The SEM image of the fracture surface of the sintered NdFeB magnet material in Comparative Example 1 is shown below. Figure 5 As shown. From Figure 5 It can be seen that for conventional magnetic materials (those not prepared by the method provided in this invention, i.e., the sintered NdFeB magnetic material of Comparative Example 1), during fracture, the cracks mainly propagate along the Nd-rich phase, and the fracture mode is predominantly intergranular fracture. Under this fracture mode, the bending strength of the magnet is significantly lower than that of the transgranular fracture mode of this invention.

[0124] The sintered NdFeB magnet materials of Examples 1, 2, Comparative Example 1, and Comparative Example 2 were subjected to flexural strength tests. The sample dimensions and test methods were performed in accordance with GB / T 31967.2-2015. During the test, the orientation of the sample was parallel to the loading direction. The measured flexural strength values ​​are shown in Table 1.

[0125] Table 1. Bending strength values ​​(unit: MPa)

[0126] Sample number Example 1 Example 2 Comparative Example 1 Comparative Example 2 1 396.3217 400.481 246.4395 298.0194 2 383.0488 399.3388 274.1872 307.9202 3 416.1029 423.9381 236.3146 314.8314 4 382.7532 367.1292 285.9856 282.9635 5 370.1536 422.1069 272.328 332.9502

[0127] As shown in Table 1, the sintered NdFeB magnet materials of the present invention (Examples 1 and 2) typically exhibit a flexural strength of 360 MPa to 430 MPa. In contrast, Comparative Examples 1 and 2 show typical flexural strength values ​​of 240 MPa to 340 MPa. This comparison of typical flexural strength values ​​demonstrates that the sintered NdFeB magnet materials of the present invention possess superior mechanical strength.

Claims

1. A method of producing a sintered neodymium-iron-boron magnet material, characterized in that, It comprises the following steps: The raw material mixture of the sintered neodymium-iron-boron magnet material is sequentially subjected to smelting, casting, crushing, forming, sintering and aging treatment to obtain the sintered neodymium-iron-boron magnet material; In the rapid solidification casting method, the rotating speed of the copper roller is 2 m / s~4 m / s, and the cooling water temperature is 5℃~15℃; the thickness of the rapid solidification piece is 0.1 mm~0.25 mm; The raw material of the sintered neodymium-iron-boron magnet material comprises the following components: B，0.9%~0.92%； X, 0.05%~0.45%, the X being one or both of Zr and Ti; Ga, 0.4%~0.6%; Y, 28%~31%, the Y being one or both of Pr and Nd; Z, 0%~2%, the Z being one or both of Dy and Tb; Cu, 0.5%~0.7%; Co, 0%~1%; Al，0%~1%； Fe, the balance; Wherein %, refers to the mass percentage of each component in the total mass of all raw materials of the sintered neodymium-iron-boron magnet material; the sum of the mass percentages of each component is 100%.

2. The method of producing a sintered neodymium-iron-boron magnet material according to claim 1, characterized in that, In the rapid solidification casting method, the rotating speed of the copper roller is 2.5 m / s~3.5 m / s; And / or, in the rapid solidification casting method, the cooling water temperature is 5℃~10℃; and / or the vacuum level of the smelting is 5 x 10 -2 Pa; And / or, the smelting temperature is below 1550℃; And / or, the casting temperature is 1390~1460℃; And / or, the crushing comprises hydrogen crushing and airflow mill crushing; And / or, the forming adopts a magnetic field forming method; and / or, the sintering vacuum is 5 x 10 -3 Pa; And / or, the sintering temperature is 1000~1100℃; And / or, the sintering time is 4~8h; And / or, the aging treatment comprises secondary aging treatment.

3. The method of producing a sintered neodymium-iron-boron magnet material according to claim 2, characterized in that, In the rapid solidification casting method, the thickness of the rapid solidification piece is 0.1 mm~0.2 mm; And / or, in the rapid solidification casting method, the rotating speed of the copper roller is 2.5 m / s; And / or, in the rapid solidification casting method, the cooling water temperature is 8℃; And / or, the smelting temperature is 1540℃; And / or, the casting temperature is 1410℃; And / or, the hydrogen crushing process comprises sequentially hydrogen absorption, hydrogen desorption and cooling treatment; the hydrogen absorption is carried out under a hydrogen pressure of 0.085 MPa; the hydrogen desorption is carried out under the condition of vacuumizing and temperature rising; the hydrogen desorption temperature is 480~520℃; And / or, the gas atmosphere during the airflow mill crushing has an oxidizing gas content below 100 ppm, the oxidizing gas content referring to the content of oxygen and / or moisture; And / or, the strength of the magnetic field forming method is 1.8~2.5T; And / or, the sintering temperature is 1080℃; And / or, the sintering time is 6h; And / or, the secondary aging treatment, wherein the first-stage aging temperature is 880℃~920℃; the second-stage aging temperature is 440℃~520℃; the first-stage aging treatment time is 2~4h; the second-stage aging treatment time is 1~4h.

4. The method of producing a sintered neodymium-iron-boron magnet material according to claim 3, characterized in that, The hydrogen desorption temperature is 500℃.

5. The method of producing a sintered neodymium-iron-boron magnet material according to claim 3, characterized in that, The first-stage aging temperature is 880℃.

6. The method of producing a sintered neodymium-iron-boron magnet material according to claim 3, characterized in that, The second-stage aging temperature is 490℃.

7. The method of producing a sintered neodymium-iron-boron magnet material according to claim 3, characterized in that, The first-stage aging treatment time is 3h.

8. The method of producing a sintered neodymium-iron-boron magnet material according to claim 3, characterized in that, The second aging treatment time is 3 hours.

9. The method of producing a sintered neodymium-iron-boron magnet material according to claim 1, characterized in that, The content of B is 0.91%-0.92%; And / or, the content of X is 0.15%-0.35%; And / or, the content of Ga is 0.5%-0.6%; And / or, the content of Y is 29.8%-30.5%; And / or, Y is Nd; And / or, the content of Co is 0.3%-0.5%; And / or, the content of Al is 0-0.5%.

10. The method of producing a sintered neodymium-iron-boron magnet material according to claim 9, characterized in that The content of X is 0.2%-0.35%.

11. The method of producing a sintered neodymium-iron-boron magnet material according to any one of claims 1 to 10, characterized in that, The raw material of the sintered Nd-Fe-B magnet material comprises the following components: 0.91% of B, 0.2% of Ti, 0.5% of Ga, 29.8% of Nd, 0.5% of Co, 0.5% of Cu, 0.5% of Al and 67.09% of Fe; wherein % means the mass percentage of each component in the total mass of the raw material of the sintered Nd-Fe-B magnet material, and the sum of the mass percentages of each component is 100%; Or, the raw material of the sintered Nd-Fe-B magnet material comprises the following components: 0.92% of B, 0.35% of Zr, 0.6% of Ga, 30.5% of Nd, 0.3% of Co, 0.7% of Cu and 66.63% of Fe; wherein % means the mass percentage of each component in the total mass of the raw material of the sintered Nd-Fe-B magnet material, and the sum of the mass percentages of each component is 100%.

12. The method of producing a sintered neodymium-iron-boron magnet material according to any one of claims 1 to 11, characterized in that, The raw material of the sintered Nd-Fe-B magnet material is composed of the B, the X, the Ga, the Y, the Z, the Cu, the Co, the Al and the Fe.

13. A sintered Nd-Fe-B magnet material prepared by the method of any one of claims 1-12.

14. The sintered neodymium-iron-boron magnet material of claim 13, characterized in that, The raw material thereof comprises the following components: B，0.9%~0.92%； X, 0.05%-0.45%, the X being one or both of Zr and Ti; Ga, 0.4%-0.6%; Y, 28%-31%, the Y being one or both of Pr and Nd; Z, 0%-2%, the Z being one or both of Dy and Tb; Cu, 0.5%-0.7%; Co, 0%-1%; Al，0%~1%； Fe, the balance; Wherein, % means the mass percentage of each component in the total mass of all raw materials of the sintered Nd-Fe-B magnet material; the sum of the mass percentages of each component is 100%.

15. The sintered neodymium-iron-boron magnet material of claim 14, wherein, The content of each component in the raw material is the same as described in the method of any one of claims 9-12.

16. The sintered neodymium-iron-boron magnet material according to any one of claims 13 to 15, characterized in that The sintered Nd-Fe-B magnet material comprises a Nd-rich phase, a tetragonal phase, an Fe-rich phase and an XB2 phase.

17. The sintered neodymium-iron-boron magnet material of claim 16, wherein, The content of Fe is 35%-55% by mass percentage.

18. The sintered neodymium-iron-boron magnet material of claim 17, wherein, The content of Fe is 44% by mass percentage.

19. The sintered neodymium-iron-boron magnet material of claim 16, wherein, The content of Y is 40%-60% by mass percentage.

20. The sintered neodymium-iron-boron magnet material of claim 19, wherein, The content of Y is 50% by mass percentage.

21. The sintered neodymium-iron-boron magnet material of claim 16, wherein, The area ratio of the Nd-rich phase is 5%-25%.

22. The sintered neodymium-iron-boron magnet material of claim 21, wherein, The area ratio of the Nd-rich phase is 6%.

23. The sintered neodymium-iron-boron magnet material of claim 16, wherein, The area ratio of the tetragonal phase is 70%-93%.

24. The sintered neodymium-iron-boron magnet material of claim 23, wherein, The area ratio of the tetragonal phase is 90%.

25. The sintered neodymium-iron-boron magnet material of claim 16, wherein, The area ratio of the Fe-rich phase is 2% to 25%.

26. The sintered neodymium-iron-boron magnet material of claim 25, wherein, The area ratio of the Fe-rich phase is 4%.

27. The sintered neodymium-iron-boron magnet material of claim 16, wherein, The XB2 phase is distributed in the neodymium-rich phase and / or at the edges of the tetragonal phase in the form of dispersed small dots.

28. The sintered neodymium-iron-boron magnet material of claim 16, wherein, The surface of the tetragonal phase crystal grains has lattice defects.

29. Use of a sintered neodymium-iron-boron magnet material according to any one of claims 13 to 28 as an electronic component.

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