CN112216461B - Cerium-containing neodymium-iron-boron magnet material and preparation method thereof - Google Patents
Cerium-containing neodymium-iron-boron magnet material and preparation method thereof Download PDFInfo
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- CN112216461B CN112216461B CN202011028213.7A CN202011028213A CN112216461B CN 112216461 B CN112216461 B CN 112216461B CN 202011028213 A CN202011028213 A CN 202011028213A CN 112216461 B CN112216461 B CN 112216461B
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- 229910052684 Cerium Inorganic materials 0.000 title claims abstract description 115
- GWXLDORMOJMVQZ-UHFFFAOYSA-N cerium Chemical compound [Ce] GWXLDORMOJMVQZ-UHFFFAOYSA-N 0.000 title claims abstract description 115
- 229910001172 neodymium magnet Inorganic materials 0.000 title claims abstract description 99
- 239000000463 material Substances 0.000 title claims abstract description 96
- 238000002360 preparation method Methods 0.000 title claims abstract description 12
- 229910052779 Neodymium Inorganic materials 0.000 claims abstract description 42
- QEFYFXOXNSNQGX-UHFFFAOYSA-N neodymium atom Chemical compound [Nd] QEFYFXOXNSNQGX-UHFFFAOYSA-N 0.000 claims abstract description 42
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 claims abstract description 36
- 229910052688 Gadolinium Inorganic materials 0.000 claims abstract description 32
- UIWYJDYFSGRHKR-UHFFFAOYSA-N gadolinium atom Chemical compound [Gd] UIWYJDYFSGRHKR-UHFFFAOYSA-N 0.000 claims abstract description 32
- 239000002994 raw material Substances 0.000 claims abstract description 23
- 239000010949 copper Substances 0.000 claims abstract description 19
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 claims abstract description 17
- 229910052782 aluminium Inorganic materials 0.000 claims abstract description 17
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 claims abstract description 17
- 229910052802 copper Inorganic materials 0.000 claims abstract description 17
- 229910052742 iron Inorganic materials 0.000 claims abstract description 17
- 239000010955 niobium Substances 0.000 claims abstract description 17
- ZOXJGFHDIHLPTG-UHFFFAOYSA-N Boron Chemical compound [B] ZOXJGFHDIHLPTG-UHFFFAOYSA-N 0.000 claims abstract description 16
- 238000003723 Smelting Methods 0.000 claims abstract description 16
- 229910052796 boron Inorganic materials 0.000 claims abstract description 16
- 229910052758 niobium Inorganic materials 0.000 claims abstract description 15
- GUCVJGMIXFAOAE-UHFFFAOYSA-N niobium atom Chemical compound [Nb] GUCVJGMIXFAOAE-UHFFFAOYSA-N 0.000 claims abstract description 15
- 238000005245 sintering Methods 0.000 claims abstract description 13
- 238000010298 pulverizing process Methods 0.000 claims abstract description 6
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 claims description 48
- 239000007788 liquid Substances 0.000 claims description 30
- 239000007789 gas Substances 0.000 claims description 29
- 239000000843 powder Substances 0.000 claims description 24
- 229910052757 nitrogen Inorganic materials 0.000 claims description 23
- 230000032683 aging Effects 0.000 claims description 17
- 239000011261 inert gas Substances 0.000 claims description 16
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 claims description 15
- 239000001257 hydrogen Substances 0.000 claims description 15
- 229910052739 hydrogen Inorganic materials 0.000 claims description 15
- 239000001307 helium Substances 0.000 claims description 11
- 229910052734 helium Inorganic materials 0.000 claims description 11
- SWQJXJOGLNCZEY-UHFFFAOYSA-N helium atom Chemical compound [He] SWQJXJOGLNCZEY-UHFFFAOYSA-N 0.000 claims description 11
- 238000002844 melting Methods 0.000 claims description 10
- 230000008018 melting Effects 0.000 claims description 10
- 238000000034 method Methods 0.000 claims description 9
- 238000003825 pressing Methods 0.000 claims description 8
- 238000010902 jet-milling Methods 0.000 claims description 6
- 238000001035 drying Methods 0.000 claims description 5
- 238000000462 isostatic pressing Methods 0.000 claims description 5
- 229910052743 krypton Inorganic materials 0.000 claims description 5
- DNNSSWSSYDEUBZ-UHFFFAOYSA-N krypton atom Chemical compound [Kr] DNNSSWSSYDEUBZ-UHFFFAOYSA-N 0.000 claims description 5
- 238000004519 manufacturing process Methods 0.000 claims description 5
- XKRFYHLGVUSROY-UHFFFAOYSA-N Argon Chemical compound [Ar] XKRFYHLGVUSROY-UHFFFAOYSA-N 0.000 claims description 4
- 239000002245 particle Substances 0.000 claims description 4
- 239000000155 melt Substances 0.000 claims description 3
- 229910052754 neon Inorganic materials 0.000 claims description 3
- GKAOGPIIYCISHV-UHFFFAOYSA-N neon atom Chemical compound [Ne] GKAOGPIIYCISHV-UHFFFAOYSA-N 0.000 claims description 3
- 229910052704 radon Inorganic materials 0.000 claims description 3
- SYUHGPGVQRZVTB-UHFFFAOYSA-N radon atom Chemical compound [Rn] SYUHGPGVQRZVTB-UHFFFAOYSA-N 0.000 claims description 3
- 229910052786 argon Inorganic materials 0.000 claims description 2
- 229910001873 dinitrogen Inorganic materials 0.000 claims description 2
- 229910052724 xenon Inorganic materials 0.000 claims description 2
- FHNFHKCVQCLJFQ-UHFFFAOYSA-N xenon atom Chemical compound [Xe] FHNFHKCVQCLJFQ-UHFFFAOYSA-N 0.000 claims description 2
- 230000005415 magnetization Effects 0.000 abstract description 31
- 229910052751 metal Inorganic materials 0.000 description 40
- 239000002184 metal Substances 0.000 description 39
- 230000000052 comparative effect Effects 0.000 description 22
- QJVKUMXDEUEQLH-UHFFFAOYSA-N [B].[Fe].[Nd] Chemical compound [B].[Fe].[Nd] QJVKUMXDEUEQLH-UHFFFAOYSA-N 0.000 description 8
- 229910052761 rare earth metal Inorganic materials 0.000 description 6
- 150000002910 rare earth metals Chemical class 0.000 description 6
- 230000009286 beneficial effect Effects 0.000 description 5
- 238000010438 heat treatment Methods 0.000 description 5
- 230000001965 increasing effect Effects 0.000 description 5
- 239000000203 mixture Substances 0.000 description 5
- 238000001816 cooling Methods 0.000 description 4
- 238000004321 preservation Methods 0.000 description 4
- 239000002699 waste material Substances 0.000 description 4
- 230000002708 enhancing effect Effects 0.000 description 3
- 239000000696 magnetic material Substances 0.000 description 3
- 239000000126 substance Substances 0.000 description 3
- 229910000640 Fe alloy Inorganic materials 0.000 description 2
- JMAHHHVEVBOCPE-UHFFFAOYSA-N [Fe].[Nb] Chemical compound [Fe].[Nb] JMAHHHVEVBOCPE-UHFFFAOYSA-N 0.000 description 2
- 238000000748 compression moulding Methods 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 230000002349 favourable effect Effects 0.000 description 2
- 229910052500 inorganic mineral Inorganic materials 0.000 description 2
- 239000011707 mineral Substances 0.000 description 2
- 238000005273 aeration Methods 0.000 description 1
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 1
- RKTYLMNFRDHKIL-UHFFFAOYSA-N copper;5,10,15,20-tetraphenylporphyrin-22,24-diide Chemical compound [Cu+2].C1=CC(C(=C2C=CC([N-]2)=C(C=2C=CC=CC=2)C=2C=CC(N=2)=C(C=2C=CC=CC=2)C2=CC=C3[N-]2)C=2C=CC=CC=2)=NC1=C3C1=CC=CC=C1 RKTYLMNFRDHKIL-UHFFFAOYSA-N 0.000 description 1
- 238000005260 corrosion Methods 0.000 description 1
- 230000007797 corrosion Effects 0.000 description 1
- 239000013078 crystal Substances 0.000 description 1
- 238000001514 detection method Methods 0.000 description 1
- 230000005389 magnetism Effects 0.000 description 1
- 238000002156 mixing Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 230000003647 oxidation Effects 0.000 description 1
- 238000007254 oxidation reaction Methods 0.000 description 1
- 239000001301 oxygen Substances 0.000 description 1
- 229910052760 oxygen Inorganic materials 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- 238000003756 stirring Methods 0.000 description 1
- 230000002195 synergetic effect Effects 0.000 description 1
- 238000010998 test method Methods 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Chemical compound O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
- H01F1/00—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties
- H01F1/01—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials
- H01F1/03—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity
- H01F1/032—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of hard-magnetic materials
- H01F1/04—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of hard-magnetic materials metals or alloys
- H01F1/047—Alloys characterised by their composition
- H01F1/053—Alloys characterised by their composition containing rare earth metals
- H01F1/055—Alloys characterised by their composition containing rare earth metals and magnetic transition metals, e.g. SmCo5
- H01F1/057—Alloys characterised by their composition containing rare earth metals and magnetic transition metals, e.g. SmCo5 and IIIa elements, e.g. Nd2Fe14B
- H01F1/0571—Alloys characterised by their composition containing rare earth metals and magnetic transition metals, e.g. SmCo5 and IIIa elements, e.g. Nd2Fe14B in the form of particles, e.g. rapid quenched powders or ribbon flakes
- H01F1/0575—Alloys characterised by their composition containing rare earth metals and magnetic transition metals, e.g. SmCo5 and IIIa elements, e.g. Nd2Fe14B in the form of particles, e.g. rapid quenched powders or ribbon flakes pressed, sintered or bonded together
- H01F1/0577—Alloys characterised by their composition containing rare earth metals and magnetic transition metals, e.g. SmCo5 and IIIa elements, e.g. Nd2Fe14B in the form of particles, e.g. rapid quenched powders or ribbon flakes pressed, sintered or bonded together sintered
-
- 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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- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Manufacturing & Machinery (AREA)
- Chemical & Material Sciences (AREA)
- Crystallography & Structural Chemistry (AREA)
- Inorganic Chemistry (AREA)
- Hard Magnetic Materials (AREA)
Abstract
The application relates to the field of magnet materials, and particularly discloses a cerium-containing neodymium-iron-boron magnet material and a preparation method thereof. The weight percentages of the elements in the cerium-containing neodymium-iron-boron magnet material are as follows: neodymium: 12.80-13.80%, copper: 0.15-0.25%, boron: 0.91-0.97%, cerium: 16.50-20.50%, aluminum: 0.15-0.25%, gadolinium: 3.33-4.33%, niobium: 0.01-0.05%, the balance being iron; the preparation method comprises the following steps: s1, primary smelting; s2, remelting; s3, pulverizing; step S4, profiling; and S5, sintering. The cerium-containing neodymium-iron-boron magnet material has the advantages of being low in raw material cost, high in intrinsic coercivity and high in residual magnetization intensity.
Description
Technical Field
The present application relates to the field of magnet materials, and more particularly, to a cerium-containing neodymium-iron-boron magnet material and a preparation method thereof.
Background
Neodymium-iron-boron magnets are tetragonal crystals formed by neodymium, iron and boron, are known for high magnetism and high cost performance in the current magnet materials, and have been gradually applied to the fields of automobiles, computers, information, aviation and the like since discovery.
Neodymium metal is one of the main raw materials for producing neodymium-iron-boron magnets, and the weight percentage of the neodymium metal in the neodymium-iron-boron magnets is usually about 30%. As the amount of neodymium-iron-boron magnet increases, the demand for neodymium metal increases. However, the content of neodymium metal in minerals is limited, and thus, the increasing demand increases the price of neodymium metal, and thus the production cost of neodymium-iron-boron magnets increases.
The metal neodymium is extracted from the original rare earth resource, and the original rare earth resource commonly used for extracting neodymium generally contains about 20% of neodymium, about 50% of metal cerium and about 30% of other substances. Therefore, when a large amount of neodymium metal resources are mined, waste of cerium metal is easily caused. However, compared with neodymium, cerium is a rare earth metal element with lower price at present, so that the use of partial cerium instead of neodymium can reduce the raw material cost of the neodymium-iron-boron magnet and reduce the waste of cerium.
However, it has been found that when cerium metal is used instead of part of neodymium metal, the intrinsic coercivity and the residual magnetization of the produced neodymium-iron-boron magnet are reduced, and therefore, it is necessary to provide a cerium-containing neodymium-iron-boron magnet material having a higher intrinsic coercivity and residual magnetization.
Disclosure of Invention
In order to improve the intrinsic coercivity and the residual magnetization of the cerium-containing neodymium-iron-boron magnet material, the application provides the cerium-containing neodymium-iron-boron magnet material and a preparation method thereof.
In a first aspect, the present application provides a cerium-containing neodymium-iron-boron magnet material, which adopts the following technical scheme:
the neodymium-iron-boron magnet material containing cerium comprises the following elements in percentage by weight:
neodymium: 12.80-13.80%
Copper: 0.15-0.25%
Boron: 0.91-0.97%
Cerium: 16.50-20.50%
Aluminum: 0.15-0.25%
Gadolinium: 3.33-4.33%
Niobium: 0.01-0.05%
The balance being iron.
By adopting the technical scheme, 50-65% of metal neodymium is replaced by metal cerium, so that the raw material cost of the neodymium-iron-boron magnet material is reduced; the addition of the metal cerium can cause the reduction of intrinsic coercivity and residual magnetization, and in order to solve the problem, 3.33-4.33% of metal gadolinium is added, and the metal gadolinium can inhibit the rapid growth of each group of grains, so that the grains are refined, the anisotropic field of the cerium-containing neodymium-iron-boron magnet material is increased, the intrinsic coercivity and residual magnetization of the cerium-containing neodymium-iron-boron magnet material are improved, and the temperature stability of the cerium-containing neodymium-iron-boron magnet material is enhanced.
Preferably, the weight percentage of each element in the magnet material is as follows:
neodymium: 12.80-13.80%
Copper: 0.15-0.25%
Boron: 0.91-0.97%
Cerium: 16.50-20.50%
Aluminum: 0.15-0.25%
Gadolinium: 3.65-4.12%
Niobium: 0.01-0.05%
The balance being iron.
By adopting the technical scheme, when the weight percentage of gadolinium in the cerium-containing neodymium-iron-boron magnet material is within the range of 3.65-4.12%, the metal gadolinium can better inhibit the rapid growth of each group of grains, thereby being beneficial to improving the intrinsic coercivity and the residual magnetization of the cerium-containing neodymium-iron-boron magnet material.
In a second aspect, the present application provides a method for preparing a cerium-containing neodymium-iron-boron magnet material, which adopts the following technical scheme: the preparation method of the cerium-containing neodymium-iron-boron magnet material comprises the following steps:
step S1, primary smelting: melting copper, cerium, aluminum and gadolinium according to the proportion to obtain a molten liquid A1, and then introducing inert gas and nitrogen into the molten liquid A1 according to the molar ratio (30-40): the mixed gas formed by the steps of (1-2) is preserved for 0.5-3 hours to obtain a melt A2;
step S2, re-smelting: adding neodymium, boron, niobium and iron into the molten liquid A2 according to the proportion, continuously melting to obtain molten liquid B1, introducing inert gas into the molten liquid B1, and preserving heat for 4-5 hours to obtain molten liquid B2;
step S3, pulverizing: preparing melt B2 into a melt-spun sheet, drying, and then carrying out hydrogen breaking treatment on the dried melt-spun sheet to obtain hydrogen crushed powder; then carrying out jet milling treatment on the hydrogen crushed powder to obtain raw material powder;
step S4, profiling: pressing and forming the raw material powder in a nitrogen environment to obtain a green body, and performing secondary pressing and forming on the green body through isostatic pressing oil pressure to obtain a green body;
step S5, sintering: and sintering the blank, and then performing two-stage aging to obtain the cerium-containing neodymium-iron-boron magnet material.
By adopting the technical scheme, as the mixed gas consisting of the inert gas and the nitrogen is introduced in the step S1, the mixed gas is favorable for enhancing the compensation effect of the metal gadolinium on the metal cerium, so that the intrinsic coercivity and the residual magnetization of the cerium-containing neodymium-iron-boron magnet material produced by the raw materials according to the steps are both closer to those of the cerium-free neodymium-iron-boron magnet material.
Preferably, the inert gas in the steps S1 and S2 is any one or a combination of helium, neon, argon, krypton, xenon and radon.
By adopting the technical scheme, the inert gas can blow out oxygen or water vapor in the molten liquid A or the molten liquid B, so that the possibility of oxidation of elements in the molten liquid is reduced, the intrinsic coercivity and the residual magnetization performance of the cerium-containing neodymium-iron-boron magnet material can be improved, and the corrosion resistance of the cerium-containing magnet material can be improved; meanwhile, the inert gas can also play a role in stirring the melt A or B, so that elements in the cerium-containing neodymium-iron-boron magnet material are uniformly distributed, and the uniformity of the cerium-containing neodymium-iron-boron magnet material is enhanced.
Preferably, the mixed gas in the step S1 is formed by mixing inert gas and nitrogen according to a molar ratio (33-36): 1.5.
By adopting the technical scheme, the mixed gas in the step S1 is prepared from inert gas and nitrogen according to the molar ratio (33-36): 1.5, the prepared cerium-containing neodymium-iron-boron magnet material has better intrinsic coercivity and residual magnetization intensity, and is beneficial to improving the temperature stability of the cerium-containing neodymium-iron-boron magnet material.
Preferably, the melting temperature in step S1 is 900-1100 ℃.
By adopting the technical scheme, the melting temperature in the step S1 is controlled to be 900-1100 ℃, so that copper, cerium, aluminum and gadolinium can be completely melted.
Preferably, the melting temperature in step S2 is 1300-1500 ℃.
By adopting the technical scheme, the melting temperature in the step S2 is controlled at 1300-1500 ℃, so that all raw materials for preparing the cerium-containing neodymium iron boron magnet material can be completely melted.
Preferably, the raw material powder has an average particle diameter of 2.2-3.2 μm.
By adopting the technical scheme, when the average grain size of the raw material powder is 2.2-3.2 mu m, the blank prepared from the raw material powder with the average grain size range has small porosity, which is beneficial to enhancing the physical and mechanical properties of the cerium-containing neodymium-iron-boron magnet material.
Preferably, in the step S5, when the green body is sintered, the temperature is raised to 700-900 ℃, the temperature is kept for 30-40min, and then the temperature is raised to 1200-1300 ℃, and the temperature is kept for 2-3h.
By adopting the technical scheme, the sintering temperature is carried out in two steps, and molten phase substances can be generated, so that the magnetic material is uniformly contracted, the density of the magnetic material is increased, and the strength of the magnetic material is improved.
Preferably, the two-stage aging treatment in the step S5 includes a first-stage aging treatment and a second-stage aging treatment, where the treatment temperature of the first-stage aging treatment is 880-910 ℃, and the treatment temperature of the second-stage aging treatment is 570-620 ℃.
By adopting the technical scheme, after the cerium-containing neodymium-iron-boron magnet material is subjected to two-stage aging treatment, the physical and mechanical properties of the cerium-containing neodymium-iron-boron magnet material can be improved.
In summary, the present application has the following beneficial effects:
1. the metal cerium replaces 50-65% of metal neodymium, so that the raw material cost of the neodymium-iron-boron magnet material is reduced; the addition of the metal cerium can cause the reduction of intrinsic coercivity and residual magnetization, and in order to solve the problem, 3.33-4.33% of metal gadolinium is added, and the metal gadolinium can inhibit the rapid growth of each group of grains, so that the grains are refined, the anisotropic field of the cerium-containing neodymium-iron-boron magnet material is increased, the intrinsic coercivity and residual magnetization of the cerium-containing neodymium-iron-boron magnet material are improved, and the temperature stability of the cerium-containing neodymium-iron-boron magnet material is enhanced.
2. According to the method, as the mixed gas consisting of the inert gas and the nitrogen is introduced in the step S1, the mixed gas is favorable for enhancing the compensation effect of the metal gadolinium on the metal cerium, so that the intrinsic coercivity and the residual magnetization of the cerium-containing neodymium-iron-boron magnet material produced by the raw materials according to the steps are both closer to those of the cerium-free neodymium-iron-boron magnet material.
Detailed Description
Neodymium metal is one of the main raw materials for producing neodymium-iron-boron magnets, and the weight percentage of the neodymium metal in the neodymium-iron-boron magnets is usually about 30%. As the amount of neodymium-iron-boron magnet increases, the demand for neodymium metal increases. However, the content of neodymium metal in minerals is limited, and thus, the increasing demand increases the price of neodymium metal, and thus the production cost of neodymium-iron-boron magnets increases.
The metal neodymium is extracted from the original rare earth resource, and the original rare earth resource commonly used for extracting neodymium generally contains about 20% of neodymium, about 50% of metal cerium and about 30% of other substances. Therefore, when a large amount of neodymium metal resources are mined, waste of cerium metal is easily caused. However, compared with neodymium, cerium is a rare earth metal element with lower price at present, so that the use of partial cerium instead of neodymium can reduce the production cost of the neodymium-iron-boron magnet and reduce the waste of cerium.
Based on the above, the applicant has made some researches, and found that the larger the weight percentage content of cerium metal in the cerium-containing neodymium-iron-boron magnet material is, the lower the intrinsic coercivity and the residual magnetization of the neodymium-iron-boron magnet is.
In order to obtain a cerium-containing neodymium-iron-boron magnet with higher intrinsic coercivity and residual magnetization intensity, the applicant starts from adjusting the weight ratio of each element in the cerium-containing neodymium-iron-boron magnet and the preparation process of the cerium-containing neodymium-iron-boron magnet, and as a result, the applicant discovers that when a certain amount of gadolinium is added into the cerium-containing neodymium-iron-boron magnet material, the intrinsic coercivity and the residual magnetization intensity of the cerium-containing neodymium-iron-boron magnet material can be improved, so that the technical problem to be solved by the application is successfully solved.
The present application is described in further detail below.
The raw materials related to the application are all commercially available, wherein the boron in the application is provided by ferroboron, and the weight ratio of the boron in the ferroboron is 18.7%; niobium is provided by a niobium-iron alloy, wherein the weight ratio of niobium in the niobium-iron alloy is 5.14%; in addition, the purities of neodymium, copper, cerium, aluminum and gadolinium are all more than 99.5 percent, and the purities of iron are all more than 99.9 percent.
Examples
The composition and proportions of the cerium-containing neodymium-iron-boron magnet materials in examples 1-2 are shown in Table 1 below:
table 1 composition and ratio (wt%) of cerium-containing NdFeB magnet materials in examples 1 to 2
Component (A) | Example 1 | Example 2 |
Neodymium | 12.80 | 13.80 |
Copper (Cu) | 0.15 | 0.25 |
Boron (B) | 0.91 | 0.97 |
Cerium (Ce) | 16.50 | 20.50 |
Aluminum (Al) | 0.25 | 0.15 |
Gadolinium (Gd) | 4.33 | 3.33 |
Niobium (Nb) | 0.05 | 0.01 |
Iron (Fe) | 65.01 | 60.99 |
Example 1
The preparation method of the cerium-containing neodymium-iron-boron magnet material comprises the following steps:
step S1, primary smelting: adding copper, cerium, aluminum and gadolinium into a smelting furnace according to the proportion in the table 1, heating the smelting furnace to 900 ℃, preserving heat until the copper, the cerium, the aluminum and the gadolinium are completely melted to obtain a molten liquid A1, introducing mixed gas consisting of helium and nitrogen according to the mol ratio of 30:2 into the molten liquid A1, controlling the flow rate of the mixed gas to be 1L/h, and preserving heat for 3h to obtain a molten liquid A2;
step S2, remelting, namely adding neodymium, boron, niobium and iron into the molten liquid A2 according to the proportion in the table 1, heating a smelting furnace to 1500 ℃, preserving heat, continuing to melt to obtain molten liquid B1, introducing krypton into the molten liquid B1, controlling the flow rate of the krypton to be 2L/h, and preserving heat for 4h to obtain molten liquid B2;
step S3, pulverizing: preparing melt B2 into a melt-spun sheet, drying, and then carrying out hydrogen breaking treatment on the dried melt-spun sheet to obtain hydrogen crushed powder; then carrying out jet milling treatment on the hydrogen crushed powder to obtain raw material powder with the average particle size of 2.2 mu m;
step S4, profiling: pressing and forming raw material powder with the average grain diameter of 2.2 mu m in a nitrogen environment to obtain a green body, and performing secondary pressing and forming on the green body through isostatic pressing oil pressure to obtain a green body;
step S5, sintering: sintering the green body, firstly raising the temperature to 700 ℃, preserving heat for 40min, then raising the temperature to 1300 ℃, and preserving heat for 2h; and then carrying out two-stage aging treatment, wherein the treatment temperature of the first-stage aging treatment is 880 ℃, the heat preservation time is 1.5h, the treatment temperature of the second-stage aging treatment is 620 ℃, the heat preservation time is 2h, and finally, cooling to room temperature to obtain the cerium-containing neodymium-iron-boron magnet material.
Example 2
The preparation method of the cerium-containing neodymium-iron-boron magnet material comprises the following steps:
step S1, primary smelting: adding copper, cerium, aluminum and gadolinium into a smelting furnace according to the proportion in the table 1, heating the smelting furnace to 1100 ℃, preserving heat until the copper, the cerium, the aluminum and the gadolinium are completely melted to obtain a molten liquid A1, introducing mixed gas consisting of radon gas and nitrogen gas according to a molar ratio of 30:2 into the molten liquid A1, controlling the flow rate of the mixed gas to be 2L/h, and preserving heat for 0.5h to obtain a molten liquid A2;
step S2, remelting, namely adding neodymium, boron, niobium and iron into the molten liquid A2 according to the proportion in the table 1, heating a smelting furnace to 1300 ℃, preserving heat, continuing to melt to obtain molten liquid B1, introducing helium into the molten liquid B1, controlling the flow of the helium to be 1L/h, and preserving heat for 5 hours to obtain molten liquid B2;
step S3, pulverizing: preparing melt B2 into a melt-spun sheet, drying, and then carrying out hydrogen breaking treatment on the dried melt-spun sheet to obtain hydrogen crushed powder; then carrying out jet milling treatment on the hydrogen crushed powder to obtain raw material powder with the average particle size of 3.2 mu m;
step S4, profiling: pressing and forming raw material powder with the average grain diameter of 3.2 mu m in a nitrogen environment to obtain a green body, and performing secondary pressing and forming on the green body through isostatic pressing oil pressure to obtain a green body;
step S5, sintering: sintering the green body, firstly raising the temperature to 900 ℃, preserving heat for 30min, then raising the temperature to 1200 ℃, and preserving heat for 3h; and then carrying out two-stage aging treatment, wherein the treatment temperature of the first-stage aging treatment is 910 ℃, the heat preservation time is 1h, the treatment temperature of the second-stage aging treatment is 570 ℃, the heat preservation time is 2.5h, and finally cooling to room temperature to obtain the cerium-containing neodymium-iron-boron magnet material.
Example 3
A cerium-containing neodymium-iron-boron magnet material, which differs from example 1 in that:
in the step S1, the proportion of gadolinium to iron is different; wherein, the weight percentage of gadolinium is 3.65 percent, and the weight percentage of iron is 65.69 percent; in the step S1, the mixed gas consists of krypton and nitrogen according to a mol ratio of 30:2.
Example 4
A cerium-containing neodymium-iron-boron magnet material, which differs from example 1 in that:
in the step S1, the proportion of gadolinium to iron is different; wherein, the weight percentage of gadolinium is 4.12 percent, and the weight percentage of iron is 65.22 percent; in the step S1, the mixed gas consists of neon and nitrogen according to a molar ratio of 30:2.
Example 5
A cerium-containing neodymium-iron-boron magnet material, which differs from example 1 in that:
in the step S1, the mixed gas consists of helium and nitrogen according to a molar ratio of 40:1.
Example 6
A cerium-containing neodymium-iron-boron magnet material, which differs from example 1 in that:
in the step S1, the mixed gas consists of helium and nitrogen according to a molar ratio of 33:1.5.
Example 7
A cerium-containing neodymium-iron-boron magnet material, which differs from example 1 in that:
in the step S1, the mixed gas consists of helium and nitrogen according to a molar ratio of 36:1.5.
Example 8
A cerium-containing neodymium-iron-boron magnet material, which differs from example 1 in that:
in the step S1, the flow rate of the mixed gas is controlled to be 0.1L/h.
Example 9
A cerium-containing neodymium-iron-boron magnet material, which differs from example 1 in that:
in the step S1, the flow rate of the mixed gas is controlled to be 10L/h.
Example 10
A cerium-containing neodymium-iron-boron magnet material, which differs from example 1 in that:
and (3) introducing pure helium gas in the step S1.
Example 11
A cerium-containing neodymium-iron-boron magnet material, which differs from example 1 in that:
in step S1, pure nitrogen is introduced.
Comparative example
Comparative example 1
A neodymium iron boron magnet material comprises the following metal elements in percentage by mass:
neodymium: 31.4%
Copper: 0.15%
Boron: 0.91%
Aluminum: 0.25%
Niobium: 0.05%
Iron: 67.24%;
the preparation method of the magnet material comprises the following steps:
step S1, primary smelting: adding neodymium, copper, boron, aluminum, niobium and iron into a smelting furnace according to the proportion in the table 1, heating the smelting furnace to 1350 ℃, and preserving heat until each metal is completely melted to obtain a molten liquid C;
step S2, pulverizing: preparing melt C into a melt-spun sheet, drying, and then carrying out hydrogen breaking treatment on the dried melt-spun sheet to obtain hydrogen broken powder; then carrying out air-jet milling treatment on the hydrogen powder to obtain air-jet milled powder;
step S3, profiling: carrying out compression molding on the air-flow powder in a nitrogen environment to obtain a green body, and carrying out secondary compression molding on the green body through isostatic pressing oil pressure to obtain a green body;
step S4, sintering: vacuum sintering the blank at 1000 ℃, and then raising the temperature to 1500 ℃ for sintering for 3 hours; and then cooling to 400 ℃ at 3 ℃/min, preserving heat for 1h, cooling to room temperature at 5 ℃/min, and taking out to obtain the neodymium-iron-boron magnet material.
The compositions and proportions of the cerium-containing neodymium-iron-boron magnet materials in comparative examples 2 to 5 are shown in Table 2 below:
table 2 composition and ratio (wt%) in cerium-containing neodymium-iron-boron magnet materials in comparative examples 2 to 5
Component (A) | Comparative example 2 | Comparative example 3 | Comparative example 4 | Comparative example 5 |
Neodymium | 12.8 | 12.8 | 12.8 | 12.8 |
Copper (Cu) | 0.15 | 0.15 | 0.15 | 0.15 |
Boron (B) | 0.91 | 0.91 | 0.91 | 0.91 |
Cerium (Ce) | 16.5 | 16.5 | 16.5 | 16.5 |
Aluminum (Al) | 0.25 | 0.25 | 0.25 | 0.25 |
Gadolinium (Gd) | 1.5 | 2.5 | 5.5 | 7.5 |
Niobium (Nb) | 0.05 | 0.05 | 0.05 | 0.05 |
Iron (Fe) | 68.84 | 68.84 | 68.84 | 68.84 |
Comparative examples 2 to 5
A cerium-containing neodymium-iron-boron magnet material, which differs from example 1 in that:
the proportions of the cerium-containing neodymium-iron-boron magnet materials are shown in table 2.
Detection method/test method
(1) Intrinsic coercivity Hcj: the test is carried out by adopting a permanent magnet performance measuring device of Shanghai Sheng-on electric Limited company.
(2) Residual magnetization Br: the test is carried out by adopting a permanent magnet performance measuring device of Shanghai Sheng-on electric Limited company.
The values of the intrinsic coercive force Hcj and the residual magnetization Br of the magnet materials in the above examples 1 to 11 and comparative examples 1 to 5 are specifically referred to the following table 3:
table 3 table of performance data of magnet materials in examples 1 to 11 and comparative examples 1 to 5
Project | Example 1 | Example 2 | Example 3 | Example 4 | Example 5 | Example 6 | Example 7 | Example 8 |
Intrinsic coercivity/KOE | 9.23 | 9.34 | 9.63 | 9.59 | 9.29 | 9.76 | 9.83 | 8.82 |
Residual magnetization/KGS | 11.76 | 11.69 | 12.46 | 12.35 | 11.72 | 12.75 | 12.8 | 11.45 |
Project | Example 9 | Example 10 | Example 11 | Comparative example 1 | Comparative example 2 | Comparative example 3 | Comparative example 4 | Comparative example 5 |
Intrinsic coercivity/KOE | 8.76 | 8.06 | 8.12 | 9.84 | 5.56 | 6.34 | 6.92 | 5.78 |
Residual magnetization/KGS | 11.23 | 10.35 | 10.44 | 12.81 | 7.65 | 8.48 | 9.01 | 8.12 |
As can be seen from the combination of examples 1 to 11 and comparative example 1 and the combination of table 3, the cerium-containing neodymium-iron-boron magnet material in the present application has similar intrinsic coercivity Hcj and residual magnetization Br to the neodymium-iron-boron magnet material in comparative example 1, compared with the magnet material in comparative example 1, in which no metallic cerium is used instead of metallic neodymium, however, the use of metallic cerium in the present application is beneficial to reducing the raw material cost of the neodymium-iron-boron magnet material.
It can be seen from the combination of examples 1 to 4 and comparative examples 2 to 5 and Table 3 that when cerium metal is used instead of about 50 to 65% neodymium metal, the ratio of gadolinium in the present application affects the intrinsic coercivity Hcj and the residual magnetization Br of the cerium-containing neodymium-iron-boron material. Wherein, only when the weight percentage of gadolinium is 3.33-4.33%, the cerium-containing neodymium-iron-boron magnet material can have better intrinsic coercivity Hcj and residual magnetization Br; when the weight percentage of gadolinium is 3.65-4.12%, the intrinsic coercivity Hcj and the residual magnetization Br of the cerium-containing neodymium-iron-boron magnet material are higher; in addition, when the weight percentage of gadolinium exceeds 3.33-4.33%, the intrinsic coercivity Hcj and the residual magnetization Br of the cerium-containing neodymium-iron-boron magnet material are both reduced.
As can be seen from the combination of examples 1 and 5 to 7 and the combination of table 3, the mixture ratio of the mixed gas was changed, wherein when the molar ratio of helium to nitrogen in the mixed gas was (30 to 40): in (1-2), the intrinsic coercivity Hcj and the residual magnetization Br of the cerium-containing neodymium-iron-boron magnet material were not much different from those of the magnet material in comparative example 1, and when the molar ratio of helium to nitrogen in the mixed gas was (33-36): 1.5, the intrinsic coercivity Hcj and the residual magnetization Br of the cerium-containing neodymium-iron-boron magnet material were closer to those of the magnet material in comparative example 1.
It can be seen from the combination of examples 1-2 and examples 8-9 and the combination of Table 3 that changing the aeration rate of the mixed gas affects the intrinsic coercivity Hcj and the residual magnetization Br of the cerium-containing neodymium-iron-boron magnet material, wherein the intrinsic coercivity Hcj and the residual magnetization Br of the cerium-containing neodymium-iron-boron magnet material are preferable when the flow rate of the mixed gas is controlled to be 1-2L/h.
As can be seen from the combination of examples 1 and 10-11 and table 3, when the mixed gas in the step S1 is changed to pure inert gas or pure nitrogen, the intrinsic coercivity Hcj and the residual magnetization Br of the cerium-containing neodymium-iron-boron magnet material are both reduced, which indicates that the inert gas and nitrogen in the step S1 have a synergistic effect, and the intrinsic coercivity Hcj and the residual magnetization Br of the cerium-containing neodymium-iron-boron magnet material can be better improved only when the mixed gas of the inert gas and nitrogen is adopted.
The present embodiment is merely illustrative of the present application and is not intended to be limiting, and those skilled in the art, after having read the present specification, may make modifications to the present embodiment without creative contribution as required, but is protected by patent laws within the scope of the claims of the present application.
Claims (10)
1. The preparation method of the cerium-containing neodymium-iron-boron magnet material is characterized by comprising the following steps of:
step S1, primary smelting: melting copper, cerium, aluminum and gadolinium according to a proportion to obtain a molten liquid A1, and then introducing inert gas and nitrogen according to a mole ratio (30-40) into the molten liquid A1: the mixed gas formed by the steps of (1-2) is preserved for 0.5-3 hours to obtain a melt A2;
step S2, re-smelting: adding neodymium, boron, niobium and iron into the molten liquid A2 according to the proportion, continuously melting to obtain molten liquid B1, introducing inert gas into the molten liquid B1, and preserving heat for 4-5 hours to obtain molten liquid B2;
step S3, pulverizing: preparing melt B2 into a melt-spun sheet, drying, and then carrying out hydrogen breaking treatment on the dried melt-spun sheet to obtain hydrogen crushed powder; then carrying out jet milling treatment on the hydrogen crushed powder to obtain raw material powder;
step S4, profiling: pressing and forming the raw material powder in a nitrogen environment to obtain a green body, and performing secondary pressing and forming on the green body through isostatic pressing oil pressure to obtain a green body;
step S5, sintering: sintering the blank, and then performing two-stage aging to obtain a cerium-containing neodymium-iron-boron magnet material;
the weight percentages of the elements in the magnet material are as follows:
neodymium: 12.80-13.80%
Copper: 0.15-0.25%
Boron: 0.91-0.97%
Cerium: 16.50-20.50%
Aluminum: 0.15-0.25%
Gadolinium: 3.33-4.33%
Niobium: 0.01-0.05%
The balance being iron.
2. The method for preparing a cerium-containing neodymium-iron-boron magnet material according to claim 1, wherein the weight percentage of each element in the magnet material is as follows:
neodymium: 12.80-13.80%
Copper: 0.15-0.25%
Boron: 0.91-0.97%
Cerium: 16.50-20.50%
Aluminum: 0.15-0.25%
Gadolinium: 3.65-4.12%
Niobium: 0.01-0.05%
The balance being iron.
3. The method for preparing a cerium-containing neodymium-iron-boron magnet material according to claim 1, wherein the inert gas in the steps S1 and S2 is any one or a combination of helium, neon, argon, krypton, xenon and radon.
4. The method for preparing a cerium-containing neodymium-iron-boron magnet material according to claim 1, wherein the mixed gas in the step S1 is prepared from inert gas and nitrogen gas according to a molar ratio (33-36): 1.5.
5. The method according to any one of claims 1 to 4, wherein the melting temperature in the step S1 is 900 to 1100 ℃.
6. The method according to any one of claims 1 to 4, wherein the melting temperature in the step S2 is 1300 to 1500 ℃.
7. The method for producing a cerium-containing neodymium iron boron magnet material according to any one of claims 1 to 4, wherein the average particle diameter of the raw material powder is 2.2 to 3.2 μm.
8. The method for preparing a cerium-containing neodymium iron boron magnet material according to any one of claims 1 to 4, wherein when the green body is sintered in the step S5, the temperature is raised to 700 to 900 ℃ for 30 to 40 minutes, and then the temperature is raised to 1200 to 1300 ℃ for 2 to 3 hours.
9. The method according to any one of claims 1 to 4, wherein the two-stage aging in step S5 comprises a first-stage aging at 880 to 910 ℃ and a second-stage aging at 570 to 620 ℃.
10. A cerium-containing neodymium-iron-boron magnet material, characterized in that it is produced by a method for producing a cerium-containing neodymium-iron-boron magnet material according to any one of claims 1 to 9.
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CN102903472A (en) * | 2012-10-26 | 2013-01-30 | 宁波韵升股份有限公司 | Sintered neodymium-iron-boron magnet and preparation method thereof |
CN104167272A (en) * | 2014-07-28 | 2014-11-26 | 宁波韵升股份有限公司 | Sintered neodymium iron boron magnet containing cerium and manufacturing method thereof |
CN107610858A (en) * | 2017-08-18 | 2018-01-19 | 浙江中元磁业股份有限公司 | A kind of amount containing cerium high inexpensive N35 neodymium iron boron magnetic bodies and its sintering method |
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CN104167272A (en) * | 2014-07-28 | 2014-11-26 | 宁波韵升股份有限公司 | Sintered neodymium iron boron magnet containing cerium and manufacturing method thereof |
CN107610858A (en) * | 2017-08-18 | 2018-01-19 | 浙江中元磁业股份有限公司 | A kind of amount containing cerium high inexpensive N35 neodymium iron boron magnetic bodies and its sintering method |
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