Sintered neodymium-iron-boron radiation tile and method of manufacture and use thereof

Abstract

The application discloses a sintered neodymium-iron-boron radiation tile and a preparation method and application thereof. The preparation of the radiation tile comprises the following steps: providing a neodymium-iron-boron black tile; clamping opposite sides of the neodymium-iron-boron black tile, slowly twisting the neodymium-iron-boron black tile to a designed angle during high-temperature heat treatment, and obtaining a tile-shaped black tile; and preparing the sintered neodymium-iron-boron radiation tile through pickling and electroplating of the tile-shaped black tile. The preparation method can improve the magnetic field distribution of the original single-piece magnetic tile product, so that the radiation tile is magnetized in a radiation mode, and the magnetic field is effectively utilized.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of sintered neodymium iron boron radiation tile preparation, and particularly relates to a sintered neodymium iron boron radiation tile preparation method, a sintered neodymium iron boron radiation tile prepared by the preparation method, and application of the sintered neodymium iron boron radiation tile. BACKGROUND

[0002] Permanent magnet servo motors are widely used in the world due to high efficiency, low power consumption and high precision, and the permanent magnet inside the permanent magnet servo motor is an important core component that determines the permanent magnet servo motor. Specifically, the permanent magnet servo motor usually adopts a high-performance neodymium iron boron permanent magnet to provide an air gap magnetic field.

[0003] At present, the permanent magnet of the permanent magnet servo motor is mostly a multi-pole permanent magnet ring assembled by single tiles in parallel and radial directions, which cooperates with the rotor by bonding and other matching modes to form the main body of the motor. However, such a permanent magnet ring has the following disadvantages: the geometric center and the magnetic field center do not coincide, the surface magnetic field distribution is uneven (zigzag), and the performance of each magnetic tile is different, which easily causes large magnetic pole fluctuation and large output signal fluctuation. SUMMARY

[0004] Therefore, it is necessary to provide a sintered neodymium iron boron radiation tile preparation method, which can improve the magnetic field distribution of the original single magnetic tile product, make the radiation tile have a radiation magnetization, and effectively utilize the magnetic field.

[0005] To achieve the above purpose, the application adopts the following technical scheme:

[0006] The application first provides a sintered neodymium iron boron radiation tile preparation method, which includes the following steps:

[0007] A neodymium iron boron black sheet is provided;

[0008] The opposite sides of the neodymium iron boron black sheet are clamped, and the neodymium iron boron black sheet is slowly twisted to a designed angle during high-temperature heat treatment, so as to obtain a tile-shaped black sheet;

[0009] The tile-shaped black sheet is subjected to acid pickling and electroplating to obtain a sintered neodymium iron boron radiation tile.

[0010] In a further scheme, the preparation of the neodymium iron boron black sheet includes the following steps:

[0011] A cast sheet is obtained according to product composition batching and smelting;

[0012] The cast sheet is subjected to hydrogen absorption and then hydrogen release by using a hydrogen breaking process to obtain a coarse powder;

[0013] The coarse powder is subjected to airflow grinding to obtain a fine powder;

[0014] The fine powder is pressed and formed, and sintered to obtain a square blank;

[0015] The square blank is cut, ground, boiled, and chamfered to obtain a Nd-Fe-B black sheet.

[0016] In a further aspect, the temperature of the smelting is 1100-1500°C.

[0017] In a further aspect, the temperature of the dehydrogenation is 300-600°C.

[0018] In a further aspect, the pressure of the jet mill is 0.4-0.7 MPa.

[0019] In a further aspect, the process of the pressing and forming is as follows: the fine powder is placed in a mold, and the green body density is controlled to be 3.8-4.1 g / mm 3 -4.1g / mm 3 , and then isostatic pressing is performed to obtain a green body density of 4.4-4.6 g / mm 3 .

[0020] In a further aspect, the process of the sintering is as follows: the green body of the pressing and forming is first sintered at 1050-1080°C for 3-5 h, then is tempered at 850-950°C for 1-3 h, and then is tempered at 450-650°C for 2-5 h.

[0021] In a further aspect, the process of preparing the tile-shaped black sheet is as follows: the opposite two sides of the Nd-Fe-B black sheet are clamped, and heating is performed in a vacuum environment at a heating rate of 4-6°C / min to 900-1000°C, and then heating is performed at a heating rate of 1-3°C / min to 1030-1080°C; then the Nd-Fe-B black sheet is slowly twisted, and the twisting is stopped and the mold is removed when the designed angle is reached, and the tile-shaped black sheet is obtained after cooling.

[0022] Preferably, the twisting speed is 0.2-0.5° / min.

[0023] Preferably, the designed angle is 0°-45°.

[0024] The application further discloses a sintered Nd-Fe-B radiation tile prepared by the preparation method.

[0025] The application further discloses an application of the sintered Nd-Fe-B radiation tile in a permanent magnet servo motor.

[0026] The application has the following beneficial effects:

[0027] The existing magnetic tile is mostly cut by square or directly pressed, magnetic lines are parallel and divergent, and two or more magnetic tiles are needed to cooperate during assembly due to the angle problem, so that the magnetic field cannot be effectively utilized. The square piece is processed to the designed angle through the high-temperature pressure maintaining and torsion process, so that one magnetic tile can be perfectly matched with the assembly, and the orientation direction of the square piece is also changed with the torsion, so that the magnetic field is radiated and effectively utilized. BRIEF DESCRIPTION OF DRAWINGS

[0028] Figure 1 It is a processing schematic diagram before the torsion process in a typical embodiment of the present application.

[0029] Figure 2 It is a structure schematic diagram of the sintered neodymium-iron-boron radiation tile obtained after the torsion process. Figure 1

[0030] In the figure: 1-neodymium-iron-boron black piece; 2-torsion clamp; 3-radiation tile. DETAILED DESCRIPTION

[0031] The embodiments of the present application are described in detail below, and the embodiments described below are exemplary and are only used to explain the present application, and cannot be understood as a limitation of the present application.

[0032] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the present application belongs. The terms used in the specification of the present application herein are only for the purpose of describing the specific embodiments and are not intended to limit the present application.

[0033] The first aspect of the present application discloses a preparation method of a sintered neodymium-iron-boron radiation tile, comprising the following steps:

[0034] Providing a neodymium-iron-boron black piece;

[0035] Clamping the opposite sides of the neodymium-iron-boron black piece, slowly twisting the neodymium-iron-boron black piece to the designed angle during high-temperature heat treatment, and obtaining a tile-shaped black piece;

[0036] Obtaining a sintered neodymium-iron-boron radiation tile after pickling and electroplating the tile-shaped black piece.

[0037] In a further aspect, the neodymium-iron-boron black piece described herein refers to a sintered neodymium-iron-boron magnetic piece before electroplating, and the specific preparation process can adopt conventional means in the art. In some specific embodiments of the present application, the preparation of the neodymium-iron-boron black piece comprises the following steps:

[0038] According to the raw material composition of the product, smelting is carried out to obtain a cast piece;

[0039] ​The cast sheet is subjected to a hydrogen-breaking process to first absorb hydrogen and then dehydrogenate it to obtain coarse powder with a particle size of 45-200μm.

[0040] The coarse powder is air-milled to obtain fine powder with a particle size of 3.0-4.0 μm;

[0041] The fine powder is pressed and sintered to obtain a block blank.

[0042] The block blank is cut, ground, boiled, and chamfered to obtain neodymium iron boron black sheet.

[0043] The specific processing parameters can be adjusted according to actual conditions. In some typical embodiments of the present invention, the melting temperature is 1100-1500℃; the dehydrogenation temperature is 300℃-600℃; the pressure of the air jet mill is 0.4MPa-0.7MPa; and the pressing process is as follows: the fine powder is placed in a mold, and the green density is controlled at 3.8g / mm³. 3 -4.1g / mm 3 Then, isostatic pressing is performed to obtain a green compact with a density of 4.4 g / mm³. 3 -4.6g / mm 3 The sintering process is as follows: the pressed green body is first sintered at 1050℃-1080℃ for 3-5 hours, then tempered at 850℃-950℃ for 1-3 hours, and then tempered at 450℃-650℃ for 2-5 hours.

[0044] Furthermore, the specific preparation process of the tile-shaped black sheet is as follows: clamp the opposite sides of the NdFeB black sheet and start evacuating the vacuum. After the vacuum degree reaches ≤5.0*E-2, start heating and heat to 900℃-1000℃ at a heating rate of 4℃-6℃ / min, and then heat to 1030℃-1080℃ at a heating rate of 1℃-3℃ / min. Then, slowly twist the NdFeB black sheet (0.2-0.5° / min) until the designed angle of 0°-45° is reached, then stop twisting and demold, cool, and obtain the tile-shaped black sheet.

[0045] Figure 1 and Figure 2 The diagrams show the processing before the torsion process and the radiant tile after the torsion process.

[0046] The second aspect of the present invention provides a sintered NdFeB radiant tile, which is prepared by the preparation method described in the first aspect of the present invention. The sintered NdFeB radiant tile has high radiation orientation and uniform surface magnetic flux density distribution.

[0047] The third aspect of the present invention provides the application of sintered NdFeB radiant tiles as described in the second aspect of the present invention in permanent magnet traction machines.

[0048] The application is described below by specific examples, it should be noted that the following specific examples are for illustrative purposes only, and do not limit the scope of the application in any way, in addition, unless otherwise specified, the methods without specific conditions or steps are conventional methods, the reagents and materials used can be obtained from commercial channels.

[0049] Example 1

[0050] A preparation method of sintered neodymium-iron-boron radiation tile is provided in this embodiment, and the specific steps are as follows:

[0051] Preparation of neodymium-iron-boron black pieces

[0052] According to the product PrNd 20 B 0.98 Al 0.5 Cu 0.1 Co 0.1 Zr 0.2 Ce 12 Fe 余 The raw material composition is prepared, and the prepared raw material is smelted and cast at 1400 DEG C to obtain a cast piece;

[0053] The cast piece is first hydrogenated and then dehydrogenated at 600 DEG C by using hydrogen breaking process to obtain a coarse powder with a particle size of 100 mu m;

[0054] The coarse powder is subjected to airflow grinding under a pressure of 0.5 MPa to obtain a fine powder with a particle size of 3.0 mu m;

[0055] The fine powder is poured into a square block mold for pressing and forming, and the green body density is controlled at 3.9 g / mm 3 , and then isostatic pressing is performed to obtain a green body density of 4.5 g / mm 3 ; the green body is placed into a vacuum sintering furnace and sintered at 1050 DEG C for 6 h, and then tempered at 890 DEG C for 2 h and at 540 DEG C for 4 h to obtain the square blank product;

[0056] The square blank is subjected to cutting, grinding, boiling, and chamfering to obtain a neodymium-iron-boron black sheet F70x30x4mm with a chamfer of R0.3mm.

[0057] Preparation of sintered neodymium-iron-boron radiation tiles

[0058] The prepared Nd-Fe-B black sheet is placed in a matching hot-pressing clamp, heated to 1000°C at a temperature increasing rate of 5°C / min in a vacuum environment of 5.0*E-2, further heated to 1040°C at a temperature increasing rate of 2°C / min, the clamp is then slowly twisted, the black sheet is twisted to form a shape in the clamp at a rate of 0.5° / min, the twisting is stopped and the black sheet is demolded when the set angle of 10° is reached, and the black sheet is slowly cooled at a cooling rate of 2°C / min in a vacuum environment to prevent cracks; after cooling, the product is taken out to obtain the said tile-shaped black sheet product, and finally the product is pickled and electroplated to obtain the sintered Nd-Fe-B radiation tile.

[0059] Example 2

[0060] A method for preparing a sintered Nd-Fe-B radiation tile is provided in this embodiment, and the specific steps are as follows:

[0061] Preparation of neodymium-iron-boron black pieces

[0062] According to the product PrNd 27 B 0.98 Al 0.5 Cu 0.1 Co 0.1 Zr 0.2 Ce5Fe 余 The raw materials are prepared, and the prepared raw materials are smelted and cast at 1450°C to obtain a cast sheet;

[0063] The cast sheet is hydrogenated and then dehydrogenated at 600°C by using a hydrogen breaking process to obtain a coarse powder with a particle size of 80μm;

[0064] The coarse powder is subjected to airflow grinding at a pressure of 0.5MPa to obtain a fine powder with a particle size of 3.0μm;

[0065] The fine powder is poured into a square block mold for pressing and forming, and the green body density is controlled at 3.95g / mm 3 , and then isostatic pressing is performed to obtain a green body density of 4.5g / mm 3 ; the green body is placed in a vacuum sintering furnace and sintered at 1050°C for 6h, and then tempered at 890°C for 2h and at 540°C for 4h to obtain the said square block blank product;

[0066] The square block blank is subjected to cutting, grinding, boiling, and chamfering to obtain a Nd-Fe-B black sheet F20×20×3mm with a chamfer of R0.3mm.

[0067] Preparation of sintered neodymium-iron-boron radiation tiles

[0068] The prepared Nd-Fe-B black sheet is placed in a matching hot-pressing clamp, heated to 950°C at a temperature rising rate of 3°C / min in a vacuum environment of 5.0*E-2, further heated to 1030°C at a temperature rising rate of 2°C / min, the clamp is then slowly twisted, the black sheet is twisted to form a shape in the clamp at a rate of 0.3° / min, the twisting is stopped and the black sheet is demolded when the set angle of 15° is reached. Further slowly cool at a cooling rate of 2°C / min in a vacuum environment to prevent cracks; after cooling, the product is taken out to obtain the said tile-shaped black sheet product, finally pickled and electroplated to obtain the sintered Nd-Fe-B radiation tile.

[0069] Example 3

[0070] A method for preparing a sintered Nd-Fe-B radiation tile is provided in this embodiment, the specific steps are as follows:

[0071] Preparation of neodymium-iron-boron black pieces

[0072] According to the product PrNd 32 B 0.98 Al 0.5 Cu 0.1 Co 0.1 Zr 0.2 Fe 余 The raw material composition is prepared, the prepared raw material is smelted and cast at 1500°C to obtain a cast sheet;

[0073] The cast sheet is first hydrogenated and then dehydrogenated at 600°C by hydrogen breaking process to obtain a coarse powder with a particle size of 60μm;

[0074] The coarse powder is subjected to air jet milling at a pressure of 0.5MPa to obtain a fine powder with a particle size of 3.0μm;

[0075] The fine powder is poured into a square block mold for pressing and forming, and the green body density is controlled at 4.0g / mm 3 ; isostatic pressing is then performed to obtain a green body density of 4.5g / mm 3 ; the green body is placed in a vacuum sintering furnace and sintered at 1060°C for 6h, then tempered at 890°C for 2h and at 500°C for 4h to obtain the said square block blank product;

[0076] The square block blank is cut, ground, boiled, and chamfered to obtain a Nd-Fe-B black sheet F30×20×3mm with a chamfer of R0.3mm.

[0077] Preparation of sintered neodymium-iron-boron radiation tiles

[0078] The prepared Nd-Fe-B black sheet is placed in a matching hot-pressing clamp, heated to 950°C at a temperature increasing rate of 5°C / min in a vacuum environment of 5.0*E-2, further heated to 1050°C at a temperature increasing rate of 2°C / min, the clamp is then slowly twisted, the black sheet is twisted to form a shape in the clamp at a rate of 0.5° / min, the twisting is stopped and the black sheet is demolded when the set angle of 20° is reached. Further slowly cool at a cooling rate of 1.5°C / min in a vacuum environment to prevent cracks; after cooling, the product is taken out to obtain the said tile-shaped black sheet product, finally pickled and electroplated to obtain the sintered Nd-Fe-B radiation tile.

[0079] Example 4

[0080] A method for preparing a sintered Nd-Fe-B radiation tile is provided in this embodiment, the specific steps are as follows:

[0081] Preparation of neodymium-iron-boron black pieces

[0082] According to the product PrNd 32 B 0.98 Al 0.5 Cu 0.1 Co 0.1 Zr 0.2 Fe 余 The raw materials are mixed, melted and cast at 1100°C to obtain a cast sheet;

[0083] The cast sheet is first hydrogenated and then dehydrogenated at 300°C by hydrogen breaking process to obtain a coarse powder with a particle size of 45μm;

[0084] The coarse powder is subjected to air jet milling at a pressure of 0.4MPa to obtain a fine powder with a particle size of 3.5μm;

[0085] The fine powder is poured into a square block mold and pressed to form a green body with a density of 3.8g / mm 3 , and then isostatic pressing is performed to obtain a green body with a density of 4.4g / mm 3 ; the green body is placed in a vacuum sintering furnace and sintered at 1050°C for 5h, then tempered at 850°C for 3h and at 450°C for 5h to obtain the said square block blank product;

[0086] The square block blank is cut, ground, boiled, and chamfered to obtain a Nd-Fe-B black sheet F20×20×3mm with a chamfer of R0.3mm.

[0087] Preparation of sintered neodymium-iron-boron radiation tiles

[0088] The prepared Nd-Fe-B black sheet is placed in a matching hot-pressing clamp, heated to 900°C at a temperature rising rate of 4°C / min in a vacuum environment of 5.0*E-2, further heated to 1030°C at a temperature rising rate of 1°C / min, the clamp is then slowly twisted, the black sheet is twisted in the clamp at a rate of 0.2° / min, and the twisting is stopped and the black sheet is demolded when the set angle of 10° is reached. Further slowly cool at a cooling rate of 1.5°C / min in a vacuum environment to prevent cracks; after cooling, the product is taken out to obtain the said tile-shaped black sheet product, and finally pickled and electroplated to obtain the sintered Nd-Fe-B radiation tile.

[0089] Example 5

[0090] A method for preparing a sintered Nd-Fe-B radiation tile is provided in this embodiment, and the specific steps are as follows:

[0091] Preparation of neodymium-iron-boron black pieces

[0092] According to the product PrNd 27 B 0.98 Al 0.5 Cu 0.1 Co 0.1 Zr 0.2 Ce5Fe 余 The raw materials are mixed, melted and cast at 1500°C to obtain a cast sheet;

[0093] The cast sheet is first hydrogenated and then dehydrogenated at 500°C using a hydrogen breaking process to obtain a coarse powder with a particle size of 200μm;

[0094] The coarse powder is subjected to air jet milling at a pressure of 0.7MPa to obtain a fine powder with a particle size of 4.0μm;

[0095] The fine powder is poured into a square block mold and pressed into a green body with a density of 4.1g / mm 3 , and then isostatic pressing is performed to obtain a green body with a density of 4.6g / mm 3 ; the green body is placed in a vacuum sintering furnace and sintered at 1080°C for 3h, then tempered at 950°C for 1h and at 650°C for 2h to obtain the said square block blank product;

[0096] The square block blank is cut, ground, boiled, and chamfered to obtain a Nd-Fe-B black sheet F20×20×3mm with a chamfer of R0.3mm.

[0097] Preparation of sintered neodymium-iron-boron radiation tiles

[0098] The prepared Nd-Fe-B black sheet is placed in a matching hot-pressing clamp, heated to 1000°C at a temperature increasing rate of 6°C / min in a vacuum environment of 5.0*E-2, further heated to 1080°C at a temperature increasing rate of 3°C / min, the clamp is then slowly twisted, the black sheet is twisted to form in the clamp at a rate of 0.3° / min, the twisting is stopped and the black sheet is demolded when the set angle of 45° is reached. Further, the product is slowly cooled at a cooling rate of 2°C / min in a vacuum environment to prevent cracks; after the cooling is completed, the product is taken out to obtain the said tile-shaped black sheet product, finally, the product is pickled and electroplated to obtain the sintered Nd-Fe-B radiation tile.

[0099] The technical features of the above-mentioned embodiments can be combined in any manner. In order to make the description simple, all possible combinations of the technical features in the above-mentioned embodiments are not described, however, as long as the combinations of the technical features do not contradict, they should be considered as the scope of the present disclosure.

[0100] The above-mentioned embodiments only express several implementation manners of the present application, the description is relatively specific and detailed, however, it should not be understood as a limitation on the scope of the patent. It should be pointed out that, for those skilled in the art, several modifications and improvements can be made without departing from the concept of the present application, these all belong to the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the appended claims.

Claims

1. A method of producing a sintered neodymium-iron-boron radiation tile, characterized in that The preparation method comprises the following steps: Providing a neodymium-iron-boron black sheet; Clamping opposite sides of the neodymium-iron-boron black sheet, slowly twisting the neodymium-iron-boron black sheet to a designed angle during high-temperature heat treatment, and obtaining a tile-shaped black sheet; Obtaining a sintered neodymium-iron-boron radiation tile by acid pickling and electroplating the tile-shaped black sheet.

2. The production method according to claim 1, wherein The preparation of the neodymium-iron-boron black sheet comprises the following steps: According to product composition, ingredients are prepared, and smelting is performed to obtain a cast sheet; The cast sheet is hydrogenated and then dehydrogenated by using a hydrogen breaking process to obtain a coarse powder; The coarse powder is subjected to airflow grinding to obtain a fine powder; The fine powder is pressed into a shape, and sintered to obtain a square blank; The square blank is cut, ground, boiled, and chamfered to obtain a neodymium-iron-boron black sheet.

3. The production method according to claim 2, wherein The smelting temperature is 1100-1500℃.

4. The production method according to claim 2, wherein The dehydrogenation temperature is 300-600℃.

5. The production method according to claim 2, wherein The pressure of the airflow grinding is 0.4-0.7MPa.

6. The production method according to claim 2, wherein The process of the press forming is: placing the fine powder in a mold, controlling the green density at 3.8g / mm 3 -4.1g / mm 3 , and then isostatic pressing to obtain a green density of 4.4-4.6g / mm 3 .

7. The production method according to claim 2, wherein The sintering process is as follows: the green body obtained by pressing into a shape is first sintered at 1050-1080℃ for 3-5h, then tempered at 850-950℃ for 1-3h, and then tempered at 450-650℃ for 2-5h.

8. The production method according to claim 1, wherein The preparation process of the tile-shaped black sheet is as follows: opposite sides of the neodymium-iron-boron black sheet are clamped, and the temperature is raised to 900-1000℃ at a rate of 4-6℃ / min in a vacuum environment, and then the temperature is raised to 1030-1080℃ at a rate of 1-3℃ / min; then the neodymium-iron-boron black sheet is slowly twisted, and the twisting is stopped when the designed angle is reached, and the tile-shaped black sheet is obtained after demolding and cooling.

9. The production method according to claim 8, wherein The twisting speed is 0.2-0.5° / min.

10. The production method according to claim 8, wherein The designed angle is 0°-45°.

11. A sintered neodymium-iron-boron radiation tile, characterized in that The sintered neodymium-iron-boron radiation tile is prepared by using the preparation method of any one of claims 1-10.

12. Application of the sintered neodymium-iron-boron radiation tile of claim 11 in a permanent magnet servo motor.

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