CN110444387B - Preparation method of high-performance sintered neodymium-iron-boron magnet - Google Patents
Preparation method of high-performance sintered neodymium-iron-boron magnet Download PDFInfo
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- CN110444387B CN110444387B CN201910765838.2A CN201910765838A CN110444387B CN 110444387 B CN110444387 B CN 110444387B CN 201910765838 A CN201910765838 A CN 201910765838A CN 110444387 B CN110444387 B CN 110444387B
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- 229910001172 neodymium magnet Inorganic materials 0.000 title claims abstract description 133
- 238000002360 preparation method Methods 0.000 title claims abstract description 8
- QJVKUMXDEUEQLH-UHFFFAOYSA-N [B].[Fe].[Nd] Chemical compound [B].[Fe].[Nd] QJVKUMXDEUEQLH-UHFFFAOYSA-N 0.000 claims abstract description 115
- 239000000843 powder Substances 0.000 claims abstract description 108
- 229910045601 alloy Inorganic materials 0.000 claims abstract description 54
- 239000000956 alloy Substances 0.000 claims abstract description 54
- 238000010438 heat treatment Methods 0.000 claims abstract description 54
- 238000000034 method Methods 0.000 claims abstract description 51
- 239000002994 raw material Substances 0.000 claims abstract description 49
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 claims abstract description 43
- 239000001257 hydrogen Substances 0.000 claims abstract description 43
- 229910052739 hydrogen Inorganic materials 0.000 claims abstract description 43
- 238000003723 Smelting Methods 0.000 claims abstract description 41
- 238000005245 sintering Methods 0.000 claims abstract description 30
- 238000010902 jet-milling Methods 0.000 claims abstract description 28
- 238000000748 compression moulding Methods 0.000 claims abstract description 27
- 238000009826 distribution Methods 0.000 claims abstract description 17
- 239000002245 particle Substances 0.000 claims abstract description 17
- 238000010521 absorption reaction Methods 0.000 claims abstract description 13
- 238000006356 dehydrogenation reaction Methods 0.000 claims abstract description 12
- 238000000926 separation method Methods 0.000 claims abstract description 12
- 239000000203 mixture Substances 0.000 claims abstract description 3
- 238000001816 cooling Methods 0.000 claims description 24
- 239000012159 carrier gas Substances 0.000 claims description 20
- 238000000465 moulding Methods 0.000 claims description 11
- 238000000227 grinding Methods 0.000 claims 4
- 239000000463 material Substances 0.000 abstract description 27
- 230000003647 oxidation Effects 0.000 abstract description 3
- 238000007254 oxidation reaction Methods 0.000 abstract description 3
- 238000003801 milling Methods 0.000 abstract description 2
- 229910052751 metal Inorganic materials 0.000 description 28
- 239000002184 metal Substances 0.000 description 28
- 239000010949 copper Substances 0.000 description 18
- XEEYBQQBJWHFJM-UHFFFAOYSA-N iron Substances [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 16
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 12
- 229910052802 copper Inorganic materials 0.000 description 12
- ZOXJGFHDIHLPTG-UHFFFAOYSA-N Boron Chemical compound [B] ZOXJGFHDIHLPTG-UHFFFAOYSA-N 0.000 description 9
- 229910052796 boron Inorganic materials 0.000 description 9
- 238000002156 mixing Methods 0.000 description 8
- 238000005303 weighing Methods 0.000 description 8
- 229910000640 Fe alloy Inorganic materials 0.000 description 6
- 230000000052 comparative effect Effects 0.000 description 5
- 229910052689 Holmium Inorganic materials 0.000 description 4
- 229910017052 cobalt Inorganic materials 0.000 description 4
- 239000010941 cobalt Substances 0.000 description 4
- GUTLYIVDDKVIGB-UHFFFAOYSA-N cobalt atom Chemical compound [Co] GUTLYIVDDKVIGB-UHFFFAOYSA-N 0.000 description 4
- KJZYNXUDTRRSPN-UHFFFAOYSA-N holmium atom Chemical compound [Ho] KJZYNXUDTRRSPN-UHFFFAOYSA-N 0.000 description 4
- NOYZXJGXUNSQQU-UHFFFAOYSA-N holmium iron Chemical compound [Fe].[Fe].[Fe].[Fe].[Fe].[Fe].[Fe].[Fe].[Fe].[Ho] NOYZXJGXUNSQQU-UHFFFAOYSA-N 0.000 description 4
- 229910052692 Dysprosium Inorganic materials 0.000 description 2
- 229910052782 aluminium Inorganic materials 0.000 description 2
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 2
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 2
- KBQHZAAAGSGFKK-UHFFFAOYSA-N dysprosium atom Chemical compound [Dy] KBQHZAAAGSGFKK-UHFFFAOYSA-N 0.000 description 2
- 229910052742 iron Inorganic materials 0.000 description 2
- 239000000696 magnetic material Substances 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 239000001301 oxygen Substances 0.000 description 2
- 229910052760 oxygen Inorganic materials 0.000 description 2
- 229910052779 Neodymium Inorganic materials 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 150000004678 hydrides Chemical class 0.000 description 1
- 230000005389 magnetism Effects 0.000 description 1
- 230000005415 magnetization Effects 0.000 description 1
- 238000010248 power generation Methods 0.000 description 1
- 229910052761 rare earth metal Inorganic materials 0.000 description 1
- 150000002910 rare earth metals Chemical class 0.000 description 1
- 238000012827 research and development Methods 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 238000010998 test method Methods 0.000 description 1
Classifications
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F9/00—Making metallic powder or suspensions thereof
- B22F9/02—Making metallic powder or suspensions thereof using physical processes
- B22F9/023—Hydrogen absorption
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F9/00—Making metallic powder or suspensions thereof
- B22F9/02—Making metallic powder or suspensions thereof using physical processes
- B22F9/04—Making metallic powder or suspensions thereof using physical processes starting from solid material, e.g. by crushing, grinding or milling
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
- H01F41/00—Apparatus or processes specially adapted for manufacturing or assembling magnets, inductances or transformers; Apparatus or processes specially adapted for manufacturing materials characterised by their magnetic properties
- H01F41/02—Apparatus or processes specially adapted for manufacturing or assembling magnets, inductances or transformers; Apparatus or processes specially adapted for manufacturing materials characterised by their magnetic properties for manufacturing cores, coils, or magnets
- H01F41/0253—Apparatus or processes specially adapted for manufacturing or assembling magnets, inductances or transformers; Apparatus or processes specially adapted for manufacturing materials characterised by their magnetic properties for manufacturing cores, coils, or magnets for manufacturing permanent magnets
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
- H01F41/00—Apparatus or processes specially adapted for manufacturing or assembling magnets, inductances or transformers; Apparatus or processes specially adapted for manufacturing materials characterised by their magnetic properties
- H01F41/02—Apparatus or processes specially adapted for manufacturing or assembling magnets, inductances or transformers; Apparatus or processes specially adapted for manufacturing materials characterised by their magnetic properties for manufacturing cores, coils, or magnets
- H01F41/0253—Apparatus or processes specially adapted for manufacturing or assembling magnets, inductances or transformers; Apparatus or processes specially adapted for manufacturing materials characterised by their magnetic properties for manufacturing cores, coils, or magnets for manufacturing permanent magnets
- H01F41/0266—Moulding; Pressing
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F9/00—Making metallic powder or suspensions thereof
- B22F9/02—Making metallic powder or suspensions thereof using physical processes
- B22F9/04—Making metallic powder or suspensions thereof using physical processes starting from solid material, e.g. by crushing, grinding or milling
- B22F2009/044—Making metallic powder or suspensions thereof using physical processes starting from solid material, e.g. by crushing, grinding or milling by jet milling
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F2998/00—Supplementary information concerning processes or compositions relating to powder metallurgy
- B22F2998/10—Processes characterised by the sequence of their steps
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- Power Engineering (AREA)
- Manufacturing & Machinery (AREA)
- Hard Magnetic Materials (AREA)
- Manufacture Of Metal Powder And Suspensions Thereof (AREA)
Abstract
The invention discloses a preparation method of a high-performance sintered neodymium-iron-boron magnet, which comprises the following steps: (1) preparing raw materials according to the finally obtained composition of the sintered neodymium-iron-boron magnet; (2) putting the raw materials into a smelting device for alloy smelting to obtain a neodymium iron boron alloy sheet; (3) carrying out hydrogen absorption crushing treatment on the neodymium iron boron alloy sheet, and semi-dehydrogenating after crushing to obtain neodymium iron boron coarse powder; (4) carrying out jet milling on the neodymium iron boron coarse powder at low temperature, and then carrying out secondary cyclone separation to obtain neodymium iron boron fine powder with uniform particle size distribution; (5) carrying out compression molding on the neodymium iron boron fine powder at low temperature; (6) finally, the target product is obtained through sintering and heat treatment. In the hydrogen crushing process, the material is subjected to semi-dehydrogenation treatment, so that the brittleness and the oxidation resistance of coarse powder are improved; and the steps of airflow milling, compression molding and the like are carried out at low temperature, so that the magnetic performance of the finally prepared sintered neodymium-iron-boron magnet is obviously improved.
Description
Technical Field
The invention belongs to the technical field of rare earth permanent magnet materials, and particularly relates to a preparation method of a high-performance sintered neodymium-iron-boron magnet.
Background
The sintered neodymium-iron-boron magnet is a magnetic material with the strongest magnetism so far, is widely applied to the fields of aerospace, automobile industry, electronic and electric appliances, medical instruments, energy-saving motors, new energy, wind power generation and the like, and is a permanent magnetic material which is fastest in development and has the best market prospect in the world at present. The sintered neodymium-iron-boron magnet has the outstanding advantages of high magnetic energy product, high coercive force, high energy density, high cost performance, good mechanical property and the like, and plays an important role in the high and new technology field.
Through research and development for more than 30 years, a production process route of alloy smelting → hydrogen crushing → jet mill → molding → sintering → heat treatment for the sintered neodymium-iron-boron magnet is basically formed, the mass production and the application of the magnets of more than 100 grades in the category of N-TH 7 are realized, and the use requirements of a plurality of application fields are met. However, on one hand, the performance of the magnet prepared by the existing process has a large difference from the theoretical performance, and on the other hand, the performance of the existing sintered neodymium-iron-boron magnet cannot meet the application requirements of a plurality of emerging application fields. Therefore, innovation needs to be performed on the basis of the existing process route so as to further improve the magnetic performance of the sintered neodymium-iron-boron magnet and meet the application requirements of more fields.
Disclosure of Invention
Aiming at the defects of the prior art, the invention aims to provide a preparation method of a high-performance sintered neodymium iron boron magnet.
In order to achieve the purpose, the invention provides the following technical scheme:
a preparation method of a high-performance sintered neodymium-iron-boron magnet comprises the following steps:
(1) preparing raw materials: preparing raw materials according to the finally obtained composition of the sintered neodymium-iron-boron magnet;
(2) alloy smelting: putting the raw materials into a smelting device for alloy smelting to obtain a neodymium iron boron alloy sheet;
(3) hydrogen crushing: carrying out hydrogen absorption crushing treatment on the neodymium iron boron alloy sheet, and carrying out semi-dehydrogenation treatment after hydrogen absorption crushing to obtain neodymium iron boron coarse powder; the hydrogen content in the neodymium iron boron coarse powder is controlled, and the brittleness and the oxidation resistance of the coarse powder are improved;
(4) and (3) jet milling: cooling the jet mill chamber, the carrier gas and the neodymium iron boron coarse powder, and carrying out jet milling on the neodymium iron boron coarse powder at a low temperature to reduce the powder granularity and the oxygen content; performing secondary cyclone separation on the powder after the jet milling to obtain fine neodymium iron boron powder with uniform particle size distribution;
(5) molding: cooling the neodymium iron boron fine powder and the forming die, and then carrying out compression molding at low temperature to improve the orientation degree of the neodymium iron boron fine powder;
(6) finally, the target product is obtained through sintering and heat treatment.
In the further scheme, in the step (3), the hydrogen content of the neodymium iron boron coarse powder is 1800-3000 ppm.
In the step (3), the temperature of the jet milling chamber after the temperature reduction treatment is less than or equal to-40 ℃, the temperature of the carrier gas is less than or equal to-60 ℃, the temperature of the neodymium iron boron coarse powder is less than or equal to-40 ℃, and the temperature of the jet milling chamber and the neodymium iron boron coarse powder in the milling chamber in the jet milling process is less than or equal to-40 ℃.
In the step (4), the particle size distribution of the neodymium iron boron fine powder with uniform particle size distribution meets the requirements that D50 is more than or equal to 3 mu m and less than or equal to 4 mu m, and D90/D10 is less than or equal to 4.
In the step (5), the temperature of the neodymium iron boron fine powder after the temperature reduction treatment is less than or equal to minus 40 ℃, the temperature of a forming die is less than or equal to minus 40 ℃, and the temperature of the neodymium iron boron fine powder in the forming die and a die cavity in the compression molding process is less than or equal to minus 40 ℃.
Further, in the step (6), the sintering temperature is 1030-1100 ℃; the heat treatment comprises a first-stage heat treatment process and a second-stage heat treatment process; wherein the temperature of the first-stage heat treatment is 850-900 ℃, and the temperature of the second-stage heat treatment is 450-500 ℃.
Compared with the prior art, the invention has the beneficial effects that:
(1) in the hydrogen crushing process, the material is subjected to semi-dehydrogenation treatment, the hydrogen content in the neodymium iron boron coarse powder is controlled to be 1800-3000 ppm, and the brittleness and the oxidation resistance of the neodymium iron boron coarse powder are improved by utilizing the characteristics of higher brittleness and stronger hydrogen reducibility of neodymium iron boron alloy hydride;
(2) the preparation method utilizes the characteristics of high brittleness and low chemical activity of the neodymium iron boron alloy at low temperature to carry out jet milling on neodymium iron boron coarse powder at low temperature, so that the powder granularity and the oxygen content can be reduced; and performing secondary cyclone separation on the powder subjected to the jet milling, controlling the particle size distribution, improving the uniformity of the powder and obtaining the neodymium iron boron fine powder with uniform particle size distribution.
(3) According to the invention, by utilizing the characteristics of high saturation magnetization and coercive force of the neodymium iron boron fine powder at low temperature, the neodymium iron boron fine powder can be subjected to a larger external magnetic field force by compression molding at low temperature, so that the orientation degree of the powder is further improved, and the magnetic performance of the finally prepared sintered neodymium iron boron magnet is obviously improved.
Detailed Description
The technical solutions of the present invention will be described clearly and completely with reference to the following embodiments of the present invention, and it should be understood that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
Example 1
(1) Preparing raw materials: selecting metal Nd with the purity of 99.5 wt%, metal Fe with the purity of 99.5 wt% and ferroboron Fe-B with the boron B content of 20 wt% as raw materials, and mixing the raw materials according to the mass ratio of Nd: fe: b-31: 68:1 and weighing the raw materials;
(2) alloy smelting: putting the raw materials into a smelting device for alloy smelting to obtain a neodymium iron boron alloy sheet; wherein the rotating speed of a copper roller during alloy smelting is 1m/s, and the pouring temperature is 1400 ℃;
(3) hydrogen crushing: carrying out hydrogen absorption crushing treatment on the neodymium iron boron alloy sheet, carrying out semi-dehydrogenation treatment after hydrogen absorption crushing to obtain neodymium iron boron coarse powder, and controlling the hydrogen content in the neodymium iron boron coarse powder to be 2000 ppm;
(4) and (3) jet milling: cooling the jet mill chamber, the carrier gas and the neodymium iron boron coarse powder by using a refrigerating device, wherein the temperature of the jet mill chamber after cooling treatment is-45 ℃, the temperature of the carrier gas is-65 ℃, the temperature of the neodymium iron boron coarse powder is-45 ℃, and the temperature of the mill chamber and the material is maintained to be less than or equal to-40 ℃ in the jet mill treatment process; performing secondary cyclone separation on the material subjected to the jet milling to obtain fine neodymium iron boron powder with the particle size distribution of D50 being 3.4 mu m and D90/D10 being 3.8;
(5) molding: cooling the fine neodymium iron boron powder and the forming die, wherein the temperature of the fine neodymium iron boron powder is-45 ℃ and the temperature of the die is-45 ℃ after cooling, in the process of compression molding, the temperature of materials in the die and a die cavity is maintained to be less than or equal to-40 ℃, and the intensity of the applied oriented magnetic field is 2.0T during compression molding; the orientation degree of the fine neodymium iron boron powder is improved through low-temperature compression molding;
(6) finally, sintering and heat treating are carried out to obtain a target product; wherein the sintering temperature is 1030 ℃ and the sintering time is 5 h; the heat treatment comprises two processes of primary heat treatment and secondary heat treatment, wherein the temperature of the primary heat treatment is 900 ℃ and the time is 3 hours, and the temperature of the secondary heat treatment is 500 ℃ and the time is 3 hours.
Comparative example 1
(1) Preparing raw materials: selecting metal Nd with the purity of 99.5 wt%, metal Fe with the purity of 99.5 wt% and ferroboron Fe-B with the boron B content of 20 wt% as raw materials, and mixing the raw materials according to the mass ratio of Nd: fe: b-31: 68:1 and weighing the raw materials;
(1) alloy smelting: putting the raw materials into a smelting device for alloy smelting to obtain a neodymium iron boron alloy sheet; wherein the rotating speed of a copper roller during alloy smelting is 1m/s, and the pouring temperature is 1400 ℃;
(2) hydrogen crushing: performing normal dehydrogenation treatment on the powder in the hydrogen crushing process to obtain neodymium iron boron coarse powder, and controlling the hydrogen content in the neodymium iron boron coarse powder to be 900 ppm;
(3) and (3) jet milling: the temperature of the jet mill chamber, the temperature of the carrier gas and the temperature of the neodymium iron boron coarse powder are not reduced, the temperature of the jet mill chamber is 25 ℃, the temperature of the carrier gas is 15 ℃, the temperature of the neodymium iron boron coarse powder is 25 ℃, and the temperature of the mill chamber and the material is maintained to be less than or equal to 40 ℃ in the jet mill treatment process; performing secondary cyclone separation on the material without the jet milling to obtain neodymium iron boron powder with the particle size distribution of D50 being 3.4 mu m and D90/D10 being 4.9;
(4) molding: cooling neodymium-iron-boron powder and a forming die, wherein the temperature of the neodymium-iron-boron powder is 25 ℃, the temperature of the die is 25 ℃, the temperature of materials in the die and a die cavity is maintained to be less than or equal to 40 ℃ in the compression molding process, and the intensity of the applied oriented magnetic field is 2.0T in the compression molding process;
(5) finally, sintering and heat treating are carried out to obtain a target product; wherein the sintering temperature is 1030 ℃ and the sintering time is 5 h; the heat treatment comprises two processes of primary heat treatment and secondary heat treatment, wherein the temperature of the primary heat treatment is 900 ℃ and the time is 3 hours, and the temperature of the secondary heat treatment is 500 ℃ and the time is 3 hours.
Example 2
(1) Preparing raw materials: selecting metal Nd with the purity of 99.5 wt%, metal Fe with the purity of 99.5 wt%, metal dysprosium Dy with the purity of 99.5 wt% and ferroboron Fe-B with the boron B content of 20 wt% as raw materials, and mixing the raw materials according to the mass ratio of Nd: dy: fe: b, mixing the raw materials according to the ratio of 28:3:68:1, and weighing the raw materials;
(2) alloy smelting: putting the raw materials into a smelting device for alloy smelting to obtain a neodymium iron boron alloy sheet; wherein the rotating speed of a copper roller during alloy smelting is 1.1m/s, and the pouring temperature is 1420 ℃;
(3) hydrogen crushing: carrying out hydrogen absorption crushing treatment on the neodymium iron boron alloy sheet, carrying out semi-dehydrogenation treatment after hydrogen absorption crushing to obtain neodymium iron boron coarse powder, and controlling the hydrogen content in the neodymium iron boron coarse powder to be 2300 ppm;
(4) and (3) jet milling: cooling the jet mill chamber, the carrier gas and the neodymium iron boron coarse powder by using a refrigerating device, wherein the temperature of the jet mill chamber after cooling treatment is-50 ℃, the temperature of the carrier gas is-65 ℃, the temperature of the neodymium iron boron coarse powder is-50 ℃, and the temperature of the mill chamber and the material is maintained to be less than or equal to-40 ℃ in the jet mill treatment process; performing secondary cyclone separation on the material subjected to the jet milling to obtain fine neodymium iron boron powder with the particle size distribution of D50 being 3.6 mu m and D90/D10 being 3.8;
(5) molding: cooling the fine neodymium iron boron powder and the forming die, wherein the temperature of the fine neodymium iron boron powder is-42 ℃ and the temperature of the die is-42 ℃ after cooling, in the compression molding process, the temperature of the materials in the die and the die cavity is maintained to be less than or equal to-40 ℃, and the strength of the oriented magnetic field applied in the compression molding process is 1.8T; the orientation degree of the fine neodymium iron boron powder is improved through low-temperature compression molding;
(6) finally, sintering and heat treating are carried out to obtain a target product; wherein the sintering temperature is 1050 ℃, and the sintering time is 5 h; the heat treatment comprises two processes of primary heat treatment and secondary heat treatment, wherein the temperature of the primary heat treatment is 900 ℃ and the time is 3 hours, and the temperature of the secondary heat treatment is 500 ℃ and the time is 3 hours.
Comparative example 2
(1) Preparing raw materials: selecting metal Nd with the purity of 99.5 wt%, metal Fe with the purity of 99.5 wt%, metal dysprosium Dy with the purity of 99.5 wt% and ferroboron Fe-B with the boron B content of 20 wt% as raw materials, and mixing the raw materials according to the mass ratio of Nd: dy: fe: b, mixing the raw materials according to the ratio of 28:3:68:1, and weighing the raw materials; (ii) a
(2) Alloy smelting: putting the raw materials into a smelting device for alloy smelting to obtain a neodymium iron boron alloy sheet; wherein the rotating speed of a copper roller during alloy smelting is 1.1m/s, and the pouring temperature is 1420 ℃;
(3) hydrogen crushing: performing normal dehydrogenation treatment on the powder in the hydrogen crushing process to obtain neodymium iron boron coarse powder, and controlling the hydrogen content in the neodymium iron boron coarse powder to be 950 ppm;
(4) and (3) jet milling: the temperature of the jet mill chamber, the carrier gas and the neodymium iron boron coarse powder is not reduced, the temperature of the jet mill chamber is 23 ℃, the temperature of the carrier gas is 18 ℃, the temperature of the neodymium iron boron coarse powder is 23 ℃, and the temperature of the mill chamber and the material is maintained to be less than or equal to 40 ℃ in the jet mill treatment process; performing secondary cyclone separation on the material without the jet milling to obtain neodymium iron boron powder with the particle size distribution of D50 being 3.6 mu m and D90/D10 being 4.8;
(5) molding: cooling neodymium-iron-boron powder and a forming die, wherein the temperature of the neodymium-iron-boron powder is 23 ℃, the temperature of the die is 23 ℃, the temperature of materials in the die and a die cavity is maintained to be less than or equal to 40 ℃ in the compression molding process, and the intensity of the applied oriented magnetic field is 1.8T in the compression molding process;
(6) finally, sintering and heat treating are carried out to obtain a target product; wherein the sintering temperature is 1050 ℃, and the sintering time is 5 h; the heat treatment comprises two processes of primary heat treatment and secondary heat treatment, wherein the temperature of the primary heat treatment is 900 ℃ and the time is 3 hours, and the temperature of the secondary heat treatment is 500 ℃ and the time is 3 hours.
Example 3
(1) Preparing raw materials: selecting metal Nd with the purity of 99.5 wt%, metal Fe with the purity of 99.5 wt%, metal cobalt Co with the purity of 99.5 wt%, metal copper Cu with the purity of 99.5 wt%, holmium iron alloy Ho-Fe with the holmium Ho content of 80 wt% and ferroboron alloy Fe-B with the boron B content of 20% as raw materials according to the Nd30Ho1Fe66.8Co1Cu0.2B1(wt.%) proportioning, according to mass ratio Nd: ho: fe: co: cu: b, proportioning 30:1:66.8:1:0.2:1 and weighing the raw materials;
(2) alloy smelting: putting the raw materials into a smelting device for alloy smelting to obtain a neodymium iron boron alloy sheet; wherein the rotating speed of a copper roller during alloy smelting is 1.1m/s, and the pouring temperature is 1410 ℃;
(3) hydrogen crushing: carrying out hydrogen absorption crushing treatment on the neodymium iron boron alloy sheet, carrying out semi-dehydrogenation treatment after hydrogen absorption crushing to obtain neodymium iron boron coarse powder, and controlling the hydrogen content in the neodymium iron boron coarse powder to be 2500 ppm;
(4) and (3) jet milling: cooling the jet mill chamber, the carrier gas and the neodymium iron boron coarse powder by using a refrigerating device, wherein the temperature of the jet mill chamber after cooling treatment is-50 ℃, the temperature of the carrier gas is-65 ℃, the temperature of the neodymium iron boron coarse powder is-50 ℃, and the temperature of the mill chamber and the materials is maintained to be less than or equal to-45 ℃ in the jet mill treatment process; performing secondary cyclone separation on the material subjected to the jet milling to obtain fine neodymium iron boron powder with the particle size distribution of D50 being 3.8 mu m and D90/D10 being 3.6;
(5) molding: cooling the fine neodymium iron boron powder and the forming die, wherein the temperature of the fine neodymium iron boron powder is-50 ℃ and the temperature of the die is-50 ℃ after cooling, in the process of compression molding, the temperature of materials in the die and a die cavity is maintained to be less than or equal to-45 ℃, and the strength of the oriented magnetic field applied during compression molding is 2.1T; the orientation degree of the fine neodymium iron boron powder is improved through low-temperature compression molding;
(6) finally, sintering and heat treating are carried out to obtain a target product; wherein the sintering temperature is 1040 ℃, and the sintering time is 5 h; the heat treatment comprises two processes of primary heat treatment and secondary heat treatment, wherein the temperature of the primary heat treatment is 900 ℃ and the time is 3 hours, and the temperature of the secondary heat treatment is 480 ℃ and the time is 3 hours.
Comparative example 3
(1) Preparing raw materials: selecting metal Nd with the purity of 99.5 wt%, metal Fe with the purity of 99.5 wt%, metal cobalt Co with the purity of 99.5 wt%, metal copper Cu with the purity of 99.5 wt%, holmium iron alloy Ho-Fe with the holmium Ho content of 80 wt% and ferroboron alloy Fe-B with the boron B content of 20% as raw materials, wherein the raw materials are as follows by mass ratio: ho: fe: co: cu: b, proportioning 30:1:66.8:1:0.2:1 and weighing the raw materials; (ii) a
(2) Alloy smelting: putting the raw materials into a smelting device for alloy smelting to obtain a neodymium iron boron alloy sheet; wherein the rotating speed of a copper roller during alloy smelting is 1.1m/s, and the pouring temperature is 1410 ℃;
(3) hydrogen crushing: performing normal dehydrogenation treatment on the powder in the hydrogen crushing process to obtain neodymium iron boron coarse powder, and controlling the hydrogen content in the neodymium iron boron coarse powder to be 880 ppm;
(4) and (3) jet milling: the temperature of the jet mill chamber, the carrier gas and the neodymium iron boron coarse powder is not reduced, the temperature of the jet mill chamber is 28 ℃, the temperature of the carrier gas is 20 ℃, the temperature of the neodymium iron boron coarse powder is 28 ℃, and the temperature of the mill chamber and the material is maintained to be less than or equal to 40 ℃ in the jet mill treatment process; performing secondary cyclone separation on the material without the jet milling to obtain neodymium iron boron powder with the particle size distribution of D50 being 3.8 mu m and D90/D10 being 4.7;
(5) molding: cooling neodymium-iron-boron powder and a forming die, wherein the temperature of the neodymium-iron-boron powder is 28 ℃, the temperature of the die is 28 ℃, the temperature of materials in the die and a die cavity is maintained to be less than or equal to 40 ℃ in the compression molding process, and the intensity of the applied oriented magnetic field is 2.1T in the compression molding process;
(6) finally, sintering and heat treating are carried out to obtain a target product; wherein the sintering temperature is 1040 ℃, and the sintering time is 5 h; the heat treatment comprises two processes of primary heat treatment and secondary heat treatment, wherein the temperature of the primary heat treatment is 900 ℃ and the time is 3 hours, and the temperature of the secondary heat treatment is 480 ℃ and the time is 3 hours.
Example 4
(1) Preparing raw materials: selecting metal Nd with the purity of 99.5 wt%, metal Fe with the purity of 99.5 wt%, metal cobalt Co with the purity of 99.5 wt%, metal copper Cu with the purity of 99.5 wt%, metal aluminum Al with the purity of 99.5 wt%, holmium iron alloy Ho-Fe with the holmium Ho content of 80 wt% and ferroboron alloy Fe-B with the boron B content of 20% as raw materials, and adopting Nd, Fe and Fe alloy with the purity of 99.5 wt%, Fe and Fe alloy with the boron B content of 20% as raw materials according to the weight ratio31Ho1Fe66.6Co1Cu0.2Al0.2B1(wt.%) mixing, according to mass ratio Nd: ho: fe: co: cu: al: b, 31:1:66.6:1:0.2:0.2:1, and weighing the raw materials;
(2) alloy smelting: putting the raw materials into a smelting device for alloy smelting to obtain a neodymium iron boron alloy sheet; wherein the rotating speed of a copper roller during alloy smelting is 1.0m/s, and the pouring temperature is 1400 ℃;
(3) hydrogen crushing: carrying out hydrogen absorption crushing treatment on the neodymium iron boron alloy sheet, carrying out semi-dehydrogenation treatment after hydrogen absorption crushing to obtain neodymium iron boron coarse powder, and controlling the hydrogen content in the neodymium iron boron coarse powder to be 2800 ppm;
(4) and (3) jet milling: cooling the jet mill chamber, the carrier gas and the neodymium iron boron coarse powder by using a refrigerating device, wherein the temperature of the jet mill chamber after cooling treatment is-55 ℃, the temperature of the carrier gas is-65 ℃, the temperature of the neodymium iron boron coarse powder is-55 ℃, and the temperature of the mill chamber and the materials is maintained to be less than or equal to-50 ℃ in the jet mill treatment process; performing secondary cyclone separation on the material subjected to the jet milling to obtain fine neodymium iron boron powder with the particle size distribution of D50 being 3.6 mu m and D90/D10 being 3.8;
(5) molding: cooling the fine neodymium iron boron powder and the forming die, wherein the temperature of the fine neodymium iron boron powder is-55 ℃ and the temperature of the die is-55 ℃ after cooling, in the compression molding process, the temperature of materials in the die and a die cavity is maintained to be less than or equal to-50 ℃, and the strength of the oriented magnetic field applied in the compression molding process is 2.0T; the orientation degree of the fine neodymium iron boron powder is improved through low-temperature compression molding;
(6) finally, sintering and heat treating are carried out to obtain a target product; wherein the sintering temperature is 1030 ℃ and the sintering time is 5 h; the heat treatment comprises two processes of primary heat treatment and secondary heat treatment, wherein the temperature of the primary heat treatment is 900 ℃ and the time is 3 hours, and the temperature of the secondary heat treatment is 500 ℃ and the time is 3 hours.
Comparative example 4
(1) Preparing raw materials: selecting metal Nd with the purity of 99.5 wt%, metal Fe with the purity of 99.5 wt%, metal cobalt Co with the purity of 99.5 wt%, metal copper Cu with the purity of 99.5 wt%, metal aluminum Al with the purity of 99.5 wt%, holmium iron alloy Ho-Fe with the holmium Ho content of 80 wt% and ferroboron alloy Fe-B with the boron B content of 20% as raw materials, and mixing the raw materials according to the mass ratio of Nd: ho: fe: co: cu: al: b, 31:1:66.6:1:0.2:0.2:1, and weighing the raw materials;
(2) alloy smelting: putting the raw materials into a smelting device for alloy smelting to obtain a neodymium iron boron alloy sheet; wherein the rotating speed of a copper roller during alloy smelting is 1.0m/s, and the pouring temperature is 1400 ℃;
(3) hydrogen crushing: performing normal dehydrogenation treatment on the powder in the hydrogen crushing process to obtain neodymium iron boron coarse powder, and controlling the hydrogen content in the neodymium iron boron coarse powder to be 980 ppm;
(4) and (3) jet milling: the temperature of the jet mill chamber, the temperature of the carrier gas and the temperature of the neodymium iron boron coarse powder are not reduced, the temperature of the jet mill chamber is 20 ℃, the temperature of the carrier gas is 15 ℃, the temperature of the neodymium iron boron coarse powder is 20 ℃, and the temperature of the mill chamber and the material is maintained to be less than or equal to 40 ℃ in the jet mill treatment process; performing secondary cyclone separation on the material without the jet milling to obtain neodymium iron boron powder with the particle size distribution of D50 being 3.6 mu m and D90/D10 being 4.8;
(5) molding: cooling neodymium-iron-boron powder and a forming die, wherein the temperature of the neodymium-iron-boron powder is 20 ℃, the temperature of the die is 20 ℃, the temperature of materials in the die and a die cavity is maintained to be less than or equal to 30 ℃ in the compression molding process, and the intensity of the applied oriented magnetic field is 2.0T in the compression molding process;
(6) finally, sintering and heat treating are carried out to obtain a target product; wherein the sintering temperature is 1030 ℃ and the sintering time is 5 h; the heat treatment comprises two processes of primary heat treatment and secondary heat treatment, wherein the temperature of the primary heat treatment is 900 ℃ and the time is 3 hours, and the temperature of the secondary heat treatment is 500 ℃ and the time is 3 hours.
The magnetic properties of the sintered nd-fe-b magnets prepared in examples 1, 2, 3, 4, 1, 2, 3, 4 were respectively tested at room temperature (23 ± 1 ℃) according to the requirements of the GB/T3217-2013 permanent (hard) magnetic material-magnetic test method using a magnetic property tester and are listed in table 1.
TABLE 1 Primary magnetic Properties of the examples and comparative examples magnets
In conclusion, the main magnetic performance of the sintered neodymium-iron-boron magnet prepared by the technical scheme of the invention is obviously improved.
Although the present description is described in terms of embodiments, not every embodiment includes only a single embodiment, and such description is for clarity only, and those skilled in the art should be able to integrate the description as a whole, and the embodiments can be appropriately combined to form other embodiments as will be understood by those skilled in the art. Therefore, the above description is only a preferred embodiment of the present application, and is not intended to limit the scope of the present application; all changes which come within the meaning and range of equivalency of the claims are to be embraced within their scope.
Claims (6)
1. A preparation method of a high-performance sintered neodymium-iron-boron magnet is characterized by comprising the following steps: the method comprises the following steps:
(1) preparing raw materials: preparing raw materials according to the finally obtained composition of the sintered neodymium-iron-boron magnet;
(2) alloy smelting: putting the raw materials into a smelting device for alloy smelting to obtain a neodymium iron boron alloy sheet;
(3) hydrogen crushing: carrying out hydrogen absorption crushing treatment on the neodymium iron boron alloy sheet, and carrying out semi-dehydrogenation treatment after hydrogen absorption crushing to obtain neodymium iron boron coarse powder;
(4) and (3) jet milling: cooling the jet mill chamber, the carrier gas and the neodymium iron boron coarse powder, and carrying out jet milling on the neodymium iron boron coarse powder at a low temperature; performing secondary cyclone separation on the powder after the jet milling to obtain fine neodymium iron boron powder with uniform particle size distribution; the temperature of the airflow grinding chamber after the temperature reduction treatment is less than or equal to minus 40 ℃, the temperature of the carrier gas is less than or equal to minus 60 ℃, the temperature of the neodymium iron boron coarse powder is less than or equal to minus 40 ℃, and the temperature of the airflow grinding chamber and the neodymium iron boron coarse powder in the grinding chamber in the airflow grinding process is less than or equal to minus 40 ℃;
(5) molding: cooling the neodymium iron boron fine powder and the forming die, and then carrying out compression molding at low temperature to improve the orientation degree of the neodymium iron boron fine powder;
(6) finally, the target product is obtained through sintering and heat treatment.
2. The method of claim 1, wherein: in the step (3), the hydrogen content of the neodymium iron boron coarse powder is 1800-3000 ppm.
3. The method of claim 1, wherein: in the step (4), the particle size distribution of the neodymium iron boron fine powder with uniform particle size distribution meets the conditions that D50 is more than or equal to 3 mu m and less than or equal to 4 mu m, and D90/D10 is less than or equal to 4.
4. The method of claim 1, wherein: in the step (5), the temperature of the neodymium iron boron fine powder after the temperature reduction treatment is less than or equal to minus 40 ℃, the temperature of a forming die is less than or equal to minus 40 ℃, and the temperature of the neodymium iron boron fine powder in the forming die and a die cavity in the compression molding process is less than or equal to minus 40 ℃.
5. The method of claim 1, wherein: in the step (6), the sintering temperature is 1030-1100 ℃.
6. The method of claim 1, wherein: in the step (6), the heat treatment comprises two processes of primary heat treatment and secondary heat treatment; wherein the temperature of the first-stage heat treatment is 850-900 ℃, and the temperature of the second-stage heat treatment is 450-500 ℃.
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Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2011023673A (en) * | 2009-07-21 | 2011-02-03 | Nec Tokin Corp | Amorphous soft magnetic powder, toroidal core, inductor and choke coil |
| CN102290182A (en) * | 2011-04-29 | 2011-12-21 | 天津天和磁材技术有限公司 | Sintered neodymium iron boron material with low oxygen content and ultrahigh performance and production method thereof |
| CN103506626A (en) * | 2013-10-22 | 2014-01-15 | 宁波科田磁业有限公司 | Manufacturing method for improving sintered NdFeB magnet coercive force |
| CN106067358A (en) * | 2016-05-20 | 2016-11-02 | 江苏普隆磁电有限公司 | A kind of magnetic powder particle and preparation method thereof |
| CN107742564A (en) * | 2017-10-31 | 2018-02-27 | 中钢集团安徽天源科技股份有限公司 | A kind of method that auxiliary alloy addition of high dysprosium prepares low-cost neodymium iron boron magnet |
| CN109148138A (en) * | 2018-09-12 | 2019-01-04 | 北矿磁材（阜阳）有限公司 | A kind of preparation method of high-performance SmCo sintered permanent magnet whole process hypoxemia |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2013035628A1 (en) * | 2011-09-09 | 2013-03-14 | 戸田工業株式会社 | R-t-b rare earth magnet powder, method of producing r-t-b rare earth magnet powder and bond magnet |
-
2019
- 2019-08-19 CN CN201910765838.2A patent/CN110444387B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2011023673A (en) * | 2009-07-21 | 2011-02-03 | Nec Tokin Corp | Amorphous soft magnetic powder, toroidal core, inductor and choke coil |
| CN102290182A (en) * | 2011-04-29 | 2011-12-21 | 天津天和磁材技术有限公司 | Sintered neodymium iron boron material with low oxygen content and ultrahigh performance and production method thereof |
| CN103506626A (en) * | 2013-10-22 | 2014-01-15 | 宁波科田磁业有限公司 | Manufacturing method for improving sintered NdFeB magnet coercive force |
| CN106067358A (en) * | 2016-05-20 | 2016-11-02 | 江苏普隆磁电有限公司 | A kind of magnetic powder particle and preparation method thereof |
| CN107742564A (en) * | 2017-10-31 | 2018-02-27 | 中钢集团安徽天源科技股份有限公司 | A kind of method that auxiliary alloy addition of high dysprosium prepares low-cost neodymium iron boron magnet |
| CN109148138A (en) * | 2018-09-12 | 2019-01-04 | 北矿磁材（阜阳）有限公司 | A kind of preparation method of high-performance SmCo sintered permanent magnet whole process hypoxemia |
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