CN112216461A - 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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- CN112216461A CN112216461A CN202011028213.7A CN202011028213A CN112216461A CN 112216461 A CN112216461 A CN 112216461A CN 202011028213 A CN202011028213 A CN 202011028213A CN 112216461 A CN112216461 A CN 112216461A
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- 229910052684 Cerium Inorganic materials 0.000 title claims abstract description 109
- GWXLDORMOJMVQZ-UHFFFAOYSA-N cerium Chemical compound [Ce] GWXLDORMOJMVQZ-UHFFFAOYSA-N 0.000 title claims abstract description 109
- 239000000463 material Substances 0.000 title claims abstract description 97
- 229910001172 neodymium magnet Inorganic materials 0.000 title claims abstract description 94
- 238000002360 preparation method Methods 0.000 title abstract description 10
- 229910052779 Neodymium Inorganic materials 0.000 claims abstract description 43
- QEFYFXOXNSNQGX-UHFFFAOYSA-N neodymium atom Chemical compound [Nd] QEFYFXOXNSNQGX-UHFFFAOYSA-N 0.000 claims abstract description 43
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 claims abstract description 38
- 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
- 229910052742 iron Inorganic materials 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
- 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
- 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
- 238000003723 Smelting Methods 0.000 claims abstract description 13
- 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 45
- 239000007789 gas Substances 0.000 claims description 27
- 239000000843 powder Substances 0.000 claims description 24
- 239000007788 liquid Substances 0.000 claims description 22
- 229910052757 nitrogen Inorganic materials 0.000 claims description 20
- 230000032683 aging Effects 0.000 claims description 19
- 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
- 239000000155 melt Substances 0.000 claims description 14
- 238000002844 melting Methods 0.000 claims description 13
- 230000008018 melting Effects 0.000 claims description 13
- 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
- 238000002074 melt spinning Methods 0.000 claims description 11
- 238000000034 method Methods 0.000 claims description 10
- 230000001965 increasing effect Effects 0.000 claims description 8
- 238000000465 moulding Methods 0.000 claims description 8
- 239000002245 particle Substances 0.000 claims description 8
- 238000003825 pressing Methods 0.000 claims description 8
- 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
- XKRFYHLGVUSROY-UHFFFAOYSA-N Argon Chemical compound [Ar] XKRFYHLGVUSROY-UHFFFAOYSA-N 0.000 claims description 4
- 238000010902 jet-milling Methods 0.000 claims description 4
- 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
- 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 29
- 229910052751 metal Inorganic materials 0.000 description 43
- 239000002184 metal Substances 0.000 description 42
- 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 11
- 239000000203 mixture Substances 0.000 description 8
- 229910000640 Fe alloy Inorganic materials 0.000 description 6
- 239000013078 crystal Substances 0.000 description 6
- 229910052761 rare earth metal Inorganic materials 0.000 description 6
- 150000002910 rare earth metals Chemical class 0.000 description 6
- 229910001873 dinitrogen Inorganic materials 0.000 description 5
- 238000010438 heat treatment Methods 0.000 description 5
- 230000009286 beneficial effect Effects 0.000 description 4
- ZDVYABSQRRRIOJ-UHFFFAOYSA-N boron;iron Chemical compound [Fe]#B ZDVYABSQRRRIOJ-UHFFFAOYSA-N 0.000 description 4
- 238000001816 cooling Methods 0.000 description 4
- 238000004321 preservation Methods 0.000 description 4
- 239000002699 waste material Substances 0.000 description 4
- 238000004519 manufacturing process Methods 0.000 description 3
- 239000000126 substance Substances 0.000 description 3
- JMAHHHVEVBOCPE-UHFFFAOYSA-N [Fe].[Nb] Chemical compound [Fe].[Nb] JMAHHHVEVBOCPE-UHFFFAOYSA-N 0.000 description 2
- 239000004411 aluminium Substances 0.000 description 2
- 238000013329 compounding Methods 0.000 description 2
- 238000000748 compression moulding Methods 0.000 description 2
- 238000001514 detection method Methods 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 230000002708 enhancing effect Effects 0.000 description 2
- 230000002349 favourable effect Effects 0.000 description 2
- 229910052500 inorganic mineral Inorganic materials 0.000 description 2
- 238000003801 milling Methods 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
- 230000003247 decreasing effect Effects 0.000 description 1
- 230000005389 magnetism Effects 0.000 description 1
- 150000002739 metals Chemical class 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
- 238000003756 stirring Methods 0.000 description 1
- 230000002195 synergetic effect Effects 0.000 description 1
- 238000010998 test method Methods 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
Landscapes
- 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 percentage of each element in the cerium-containing neodymium iron boron 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: 3.33 to 4.33%, niobium: 0.01-0.05% and the balance of iron; the preparation method comprises the following steps: step S1, primary smelting; step S2, remelting; step S3, pulverizing; step S4, profiling; and step S5, sintering. The cerium-containing neodymium iron boron magnet material has the advantages of low raw material cost, high intrinsic coercive force and high residual magnetization.
Description
Technical Field
The application relates to the field of magnet materials, in particular 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, among current magnet materials, neodymium-iron-boron magnets are well known for their high magnetism and high cost performance, and are gradually applied to the fields of automobiles, computers, information, aviation and the like since their discovery.
Metal neodymium is one of the main raw materials for producing neodymium iron boron magnets, and the weight percentage of the metal neodymium in the neodymium iron boron magnets is usually about 30%. As the amount of neodymium iron boron magnets used increases, the demand for metallic neodymium also increases. However, the content of metallic neodymium in minerals is limited, and therefore, the increasing demand increases the price of metallic neodymium, resulting in an increase in the production cost of neodymium-iron-boron magnets.
Among them, metallic neodymium is extracted from a primary rare earth resource, and the primary rare earth resource usually used for extracting neodymium generally contains about 20% of neodymium, about 50% of metallic cerium and about 30% of other substances. Therefore, when a large amount of neodymium metal resources are exploited, the waste of cerium metal is easily caused. However, compared with metal neodymium, metal cerium is a rare earth metal element with a lower price at present, so that the raw material cost of the neodymium-iron-boron magnet can be reduced by adopting part of metal cerium to replace metal neodymium, and meanwhile, the waste of metal cerium can be reduced.
However, it has been found that when metal cerium is used to replace part of metal neodymium, the intrinsic coercivity and residual magnetization of the resulting ndfeb magnet are reduced, and therefore, it is desirable to provide a ndfeb magnet material containing cerium but having higher intrinsic coercivity and residual magnetization.
Disclosure of Invention
In order to improve the intrinsic coercivity and 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:
a cerium-containing neodymium-iron-boron magnet material comprises the following elements in percentage by weight:
neodymium: 12.80 to 13.80 percent
Copper: 0.15-0.25%
Boron: 0.91 to 0.97 percent
Cerium: 16.50 to 20.50 percent
Aluminum: 0.15-0.25%
Gadolinium: 3.33 to 4.33 percent
Niobium: 0.01 to 0.05 percent
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; in order to solve the problem, 3.33-4.33% of metal gadolinium is added in the neodymium iron boron magnet material, the metal gadolinium can inhibit rapid growth of each group of crystal grains, so that the crystal grains are refined, an anisotropic field of the cerium-containing neodymium iron boron magnet material is increased, the intrinsic coercive force and the residual magnetization intensity 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 percentages of the elements in the magnet material are as follows:
neodymium: 12.80 to 13.80 percent
Copper: 0.15-0.25%
Boron: 0.91 to 0.97 percent
Cerium: 16.50 to 20.50 percent
Aluminum: 0.15-0.25%
Gadolinium: 3.65-4.12%
Niobium: 0.01 to 0.05 percent
The balance being iron.
By adopting the technical scheme, when the weight percentage of the 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 crystal grains, and is favorable for improving the intrinsic coercive force and the residual magnetization intensity 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: a preparation method of a 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): (1-2), and preserving the temperature for 0.5-3h to obtain a molten liquid A2;
step S2, remelting: adding neodymium, boron, niobium and iron into the melt A2 according to the proportion, continuously melting to obtain a melt B1, introducing inert gas into the melt B1, and keeping the temperature for 4-5 hours to obtain a melt B2;
step S3, pulverizing: preparing the melt B2 into melt spinning slices, drying, and then carrying out hydrogen breaking treatment on the dried melt spinning slices to obtain hydrogen powder; then, carrying out jet milling treatment on the hydrogen crushed powder to obtain raw material powder;
step S4, profiling: pressing and molding the raw material powder in a nitrogen environment to obtain a green body, and performing secondary pressing and molding 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, because the mixed gas composed of the inert gas and the nitrogen is introduced in the step S1, the mixed gas is beneficial to enhancing the compensation effect of the metal gadolinium on the metal cerium, so that the intrinsic coercive force and the residual magnetization intensity of the cerium-containing neodymium-iron-boron magnet material produced by the raw materials according to the steps are closer to those of the neodymium-iron-boron magnet material without the metal cerium.
Preferably, the inert gas in steps S1 and S2 is any one or a combination of several of helium, neon, argon, krypton, xenon, and radon.
By adopting the technical scheme, the inert gas can blow out oxygen or moisture 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 coercive force and the residual magnetization performance of the cerium-containing neodymium iron boron magnet material are improved, and the corrosion resistance of the cerium-containing magnet material can also be improved; meanwhile, the inert gas can also play a role in stirring the molten liquid 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 step S1 is prepared by mixing an inert gas and nitrogen in 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 of (33-36):1.5, the prepared cerium-containing neodymium-iron-boron magnet material has better intrinsic coercive force and residual magnetization intensity, and is favorable for improving the temperature stability of the cerium-containing neodymium-iron-boron magnet material.
Preferably, the melting temperature in the 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 the copper, the cerium, the aluminum and the gadolinium can be completely melted.
Preferably, the melting temperature in the step S2 is 1300-1500 ℃.
By adopting the technical scheme, the melting temperature in the step S2 is controlled at 1300-1500 ℃, so that the raw materials for preparing the cerium-containing neodymium-iron-boron magnet material can be completely melted.
Preferably, the average particle diameter of the raw material powder is 2.2 to 3.2 μm.
By adopting the technical scheme, when the average particle size of the raw material powder is 2.2-3.2 microns, the blank prepared by adopting the raw material powder within the average particle size range has small porosity, and the physical and mechanical properties of the cerium-containing neodymium iron boron magnet material are enhanced.
Preferably, when the green body is sintered in the step S5, the temperature is first raised to 900 ℃ of 700-.
By adopting the technical scheme, the sintering temperature is carried out in two steps, and molten phase substances can be generated, so that the magnet material shrinks uniformly, the density of the magnet material is increased, and the strength of the magnet 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, 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, the physical and mechanical properties of the cerium-containing neodymium-iron-boron magnet material can be improved after the cerium-containing neodymium-iron-boron magnet material is subjected to two-stage aging treatment.
In summary, the present application has the following beneficial effects:
1. according to the preparation method, 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; in order to solve the problem, 3.33-4.33% of metal gadolinium is added in the neodymium iron boron magnet material, the metal gadolinium can inhibit rapid growth of each group of crystal grains, so that the crystal grains are refined, an anisotropic field of the cerium-containing neodymium iron boron magnet material is increased, the intrinsic coercive force and the residual magnetization intensity 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, since the mixed gas composed of the inert gas and the nitrogen is introduced in the step S1, the mixed gas is beneficial to enhancing the compensation effect of the metal gadolinium on the metal cerium, so that the intrinsic coercive force and the residual magnetization intensity of the neodymium iron boron magnet material containing cerium, which is produced by the raw materials according to the steps, are closer to those of the neodymium iron boron magnet material not containing the metal cerium.
Detailed Description
Metal neodymium is one of the main raw materials for producing neodymium iron boron magnets, and the weight percentage of the metal neodymium in the neodymium iron boron magnets is usually about 30%. As the amount of neodymium iron boron magnets used increases, the demand for metallic neodymium also increases. However, the content of metallic neodymium in minerals is limited, and therefore, the increasing demand increases the price of metallic neodymium, resulting in an increase in the production cost of neodymium-iron-boron magnets.
Among them, metallic neodymium is extracted from a primary rare earth resource, and the primary rare earth resource usually used for extracting neodymium generally contains about 20% of neodymium, about 50% of metallic cerium and about 30% of other substances. Therefore, when a large amount of neodymium metal resources are exploited, the waste of cerium metal is easily caused. However, compared with metal neodymium, metal cerium is a rare earth metal element with a lower price at present, so that the production cost of the neodymium-iron-boron magnet can be reduced by adopting part of metal cerium to replace metal neodymium, and meanwhile, the waste of metal cerium can be reduced.
Based on this, the applicant has made some studies, and found that the larger the content of cerium in the material of the neodymium iron boron magnet containing cerium by weight percentage, the lower the intrinsic coercive force and residual magnetization of the neodymium iron boron magnet.
In order to obtain a cerium-containing neodymium-iron-boron magnet with higher intrinsic coercivity and residual magnetization, 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 finds that when a certain amount of gadolinium is added to the cerium-containing neodymium-iron-boron magnet material, the intrinsic coercivity and the residual magnetization of the cerium-containing neodymium-iron-boron magnet material can be improved, so that the technical problems to be solved by the application are successfully solved.
The present application is described in further detail below.
The raw materials related to the boron-iron alloy are all sold in the market, wherein boron in the boron-iron alloy is provided by the boron-iron alloy, and the weight proportion of boron in the boron-iron alloy is 18.7%; the niobium is provided by niobium-iron alloy, and the weight ratio of niobium in the niobium-iron alloy is 5.14 percent; in addition, the purities of neodymium, copper, cerium, aluminum and gadolinium are all more than 99.5%, and the purity of metallic iron is more than 99.9%.
Examples
The compositions and proportions of the cerium-containing neodymium-iron-boron magnet material of examples 1-2 are shown in table 1 below:
TABLE 1 composition and compounding ratio (wt%) of Ce-containing NdFeB magnet material in examples 1-2
| Components | Example 1 | Example 2 |
| Neodymium | 12.80 | 13.80 |
| Copper (Cu) | 0.15 | 0.25 |
| Boron | 0.91 | 0.97 |
| Cerium (Ce) | 16.50 | 20.50 |
| Aluminium | 0.25 | 0.15 |
| Gadolinium (Gd) | 4.33 | 3.33 |
| Niobium (Nb) | 0.05 | 0.01 |
| Iron | 65.01 | 60.99 |
Example 1
A cerium-containing neodymium-iron-boron magnet material is prepared by 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, cerium, aluminum and gadolinium are completely melted to obtain a molten liquid A1, introducing mixed gas consisting of helium and nitrogen in a molar ratio of 30:2 into the molten liquid A1, controlling the flow 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 mixture ratio in the table 1, heating the smelting furnace to 1500 ℃, preserving heat, continuously melting to obtain molten liquid B1, introducing krypton into the molten liquid B1, controlling the flow of krypton to be 2L/h, and preserving heat for 4h to obtain molten liquid B2;
step S3, pulverizing: preparing the melt B2 into melt spinning slices, drying, and then carrying out hydrogen breaking treatment on the dried melt spinning slices to obtain hydrogen 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 microns;
step S4, profiling: pressing and molding raw material powder with the average particle size of 2.2 mu m in a nitrogen environment to obtain a green body, and performing secondary pressing and molding on the green body through isostatic pressing oil pressure to obtain a green body;
step S5, sintering: sintering the blank, namely raising the temperature to 700 ℃, preserving the heat for 40min, then raising the temperature to 1300 ℃, and preserving the heat for 2 h; 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
A cerium-containing neodymium-iron-boron magnet material is prepared by 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, cerium, aluminum and gadolinium are completely melted to obtain a molten liquid A1, introducing mixed gas consisting of radon gas and nitrogen in a molar ratio of 30:2 into the molten liquid A1, controlling the flow 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 melt A2 according to the proportion in the table 1, heating the melting furnace to 1300 ℃, preserving heat, continuing melting to obtain melt B1, introducing helium into the melt B1, controlling the flow of the helium to be 1L/h, and preserving heat for 5h to obtain melt B2;
step S3, pulverizing: preparing the melt B2 into melt spinning slices, drying, and then carrying out hydrogen breaking treatment on the dried melt spinning slices to obtain hydrogen 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 microns;
step S4, profiling: pressing and molding raw material powder with the average particle size of 3.2 mu m in a nitrogen environment to obtain a green body, and performing secondary pressing and molding on the green body through isostatic pressing oil pressure to obtain a green body;
step S5, sintering: sintering the blank, raising the temperature to 900 ℃, preserving the heat for 30min, then raising the temperature to 1200 ℃, and preserving the heat for 3 h; 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, differing from example 1 in that:
in the step S1, the mixture ratio 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 step S1, the mixed gas is composed of krypton and nitrogen in a molar ratio of 30: 2.
Example 4
A cerium-containing neodymium-iron-boron magnet material, differing from example 1 in that:
in the step S1, the mixture ratio 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 step S1, the mixed gas is composed of neon and nitrogen at a molar ratio of 30: 2.
Example 5
A cerium-containing neodymium-iron-boron magnet material, differing from example 1 in that:
the mixed gas in step S1 is composed of helium and nitrogen at a molar ratio of 40: 1.
Example 6
A cerium-containing neodymium-iron-boron magnet material, differing from example 1 in that:
the mixed gas in step S1 was composed of helium and nitrogen at a molar ratio of 33: 1.5.
Example 7
A cerium-containing neodymium-iron-boron magnet material, differing from example 1 in that:
the mixed gas in step S1 was composed of helium and nitrogen at a molar ratio of 36: 1.5.
Example 8
A cerium-containing neodymium-iron-boron magnet material, differing from example 1 in that:
in 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, differing from example 1 in that:
in step S1, the flow rate of the mixed gas is controlled to 10L/h.
Example 10
A cerium-containing neodymium-iron-boron magnet material, differing from example 1 in that:
pure helium is introduced in step S1.
Example 11
A cerium-containing neodymium-iron-boron magnet material, differing from example 1 in that:
in step S1, pure nitrogen gas 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 percent
Copper: 0.15 percent
Boron: 0.91 percent
Aluminum: 0.25 percent
Niobium: 0.05 percent
Iron: 67.24 percent;
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 all metals are completely melted to obtain molten liquid C;
step S2, pulverizing: preparing the molten liquid C into a melt spinning piece, drying the melt spinning piece, and then performing hydrogen breaking treatment on the dried melt spinning piece to obtain hydrogen broken powder; then, carrying out airflow milling treatment on the hydrogen broken powder to obtain airflow milled powder;
step S3, profiling: milling the airflow powder in a nitrogen environment, performing compression molding to obtain a green body, and performing 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 ℃, then raising the temperature to 1500 ℃, and sintering for 3 h; and then cooling to 400 ℃ at a speed of 3 ℃/min, preserving the heat for 1h, cooling to room temperature at a speed of 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 2-5 are shown in table 2 below:
TABLE 2 composition and compounding ratio (wt%) of cerium-containing Nd-Fe-B magnet material in comparative examples 2-5
| Components | 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 | 0.91 | 0.91 | 0.91 | 0.91 |
| Cerium (Ce) | 16.5 | 16.5 | 16.5 | 16.5 |
| Aluminium | 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 | 68.84 | 68.84 | 68.84 | 68.84 |
Comparative examples 2 to 5
A cerium-containing neodymium-iron-boron magnet material, differing from example 1 in that:
the proportions of the cerium-containing neodymium-iron-boron magnet material are as shown in table 2 above.
Detection method/test method
(1) Intrinsic coercive force Hcj: the test is carried out by adopting a permanent magnetic property measuring device of Shanghai Shengtong electric company Limited.
(2) Residual magnetization Br: the test is carried out by adopting a permanent magnetic property measuring device of Shanghai Shengtong electric company Limited.
The detection 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
| Item | 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 |
| Remanent magnetization/KGS | 11.76 | 11.69 | 12.46 | 12.35 | 11.72 | 12.75 | 12.8 | 11.45 |
| Item | 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 |
| Remanent 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 table 3, compared with the magnet material prepared in comparative example 1 without using metal cerium to replace metal neodymium, the intrinsic coercive force Hcj and residual magnetization Br of the neodymium-iron-boron magnet material prepared in the present application are similar to those of the neodymium-iron-boron magnet material prepared in comparative example 1, but the metal cerium is used to replace about 50 to 65% of metal neodymium in the present application, which is beneficial to reducing the raw material cost of the neodymium-iron-boron magnet material.
Combining examples 1-4 with comparative examples 2-5 and combining table 3, it can be seen that when metal cerium is used to replace about 50-65% of metal neodymium, the ratio of gadolinium in the present application will affect the intrinsic coercivity Hcj and the remanent magnetization Br of the cerium-containing neodymium-iron-boron material. Wherein, only when the weight percentage of gadolinium is 3.33-4.33%, the neodymium iron boron magnet material containing cerium has better intrinsic coercive force Hcj and residual magnetization Br; when the weight percentage of gadolinium is 3.65-4.12%, the intrinsic coercive force Hcj and 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 coercive force Hcj and the residual magnetization Br of the cerium-containing neodymium iron boron magnet material are both reduced.
Combining example 1 with examples 5-7 and combining table 3, it can be seen that the mixture ratio of the mixed gas is changed, wherein, when the molar ratio of the helium gas to the nitrogen gas in the mixed gas is (30-40): (1-2), the intrinsic coercive force Hcj and the residual magnetization Br of the cerium-containing neodymium-iron-boron magnet material are 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 is (33-36):1.5, the intrinsic coercive force Hcj and the residual magnetization Br of the cerium-containing neodymium-iron-boron magnet material are closer than 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 table 3 that changing the aeration rate of the mixed gas affects the intrinsic coercivity Hcj and residual magnetization Br of the cerium-containing ndfeb magnet material, wherein the intrinsic coercivity Hcj and residual magnetization Br of the cerium-containing ndfeb magnet material are superior when the flow rate of the mixed gas is controlled to be 1-2L/h.
When the mixed gas in step S1 is changed to pure inert gas or pure nitrogen gas, the intrinsic coercive force Hcj and the residual magnetization Br of the neodymium-iron-boron magnet material containing cerium are both decreased, as can be seen from combining examples 1 and 10-11 and table 3, which indicates that the inert gas and the nitrogen gas in step S1 have a synergistic effect, and the intrinsic coercive force Hcj and the residual magnetization Br of the neodymium-iron-boron magnet material containing cerium can be better increased only when the mixed gas of the inert gas and the nitrogen gas is used.
The present embodiment is only for explaining the present application, and it is not limited to the present application, and those skilled in the art can make modifications of the present embodiment without inventive contribution as needed after reading the present specification, but all of them are protected by patent law within the scope of the claims of the present application.
Claims (10)
1. The cerium-containing neodymium-iron-boron magnet material is characterized in that the weight percentages of all elements in the magnet material are as follows:
neodymium: 12.80 to 13.80 percent
Copper: 0.15-0.25%
Boron: 0.91 to 0.97 percent
Cerium: 16.50 to 20.50 percent
Aluminum: 0.15-0.25%
Gadolinium: 3.33 to 4.33 percent
Niobium: 0.01 to 0.05 percent
The balance being iron.
2. The cerium-containing neodymium-iron-boron magnet material according to claim 1, wherein the weight percentages of the elements in the magnet material are as follows:
neodymium: 12.80 to 13.80 percent
Copper: 0.15-0.25%
Boron: 0.91 to 0.97 percent
Cerium: 16.50 to 20.50 percent
Aluminum: 0.15-0.25%
Gadolinium: 3.65-4.12%
Niobium: 0.01 to 0.05 percent
The balance being iron.
3. The method for preparing a cerium-containing neodymium-iron-boron magnet material according to any one of claims 1 to 2, characterized by comprising the steps of:
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): (1-2), and preserving the temperature for 0.5-3h to obtain a molten liquid A2;
step S2, remelting: adding neodymium, boron, niobium and iron into the melt A2 according to the proportion, continuously melting to obtain a melt B1, introducing inert gas into the melt B1, and keeping the temperature for 4-5 hours to obtain a melt B2;
step S3, pulverizing: preparing the melt B2 into melt spinning slices, drying, and then carrying out hydrogen breaking treatment on the dried melt spinning slices to obtain hydrogen powder; then, carrying out jet milling treatment on the hydrogen crushed powder to obtain raw material powder;
step S4, profiling: pressing and molding the raw material powder in a nitrogen environment to obtain a green body, and performing secondary pressing and molding 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.
4. The method of claim 3, wherein the inert gas in steps S1 and S2 is any one or more of helium, neon, argon, krypton, xenon and radon.
5. The method of claim 3, wherein the mixed gas in step S1 is prepared from inert gas and nitrogen in a molar ratio (33-36): 1.5.
6. The method as claimed in any one of claims 3 to 5, wherein the melting temperature in step S1 is 900-1100 ℃.
7. The method as claimed in any one of claims 3 to 5, wherein the melting temperature in step S2 is 1300-1500 ℃.
8. The method for preparing a cerium-containing neodymium iron boron magnet material according to any one of claims 3 to 5, wherein the average particle size of the raw material powder is 2.2 to 3.2 μm.
9. The method as claimed in any one of claims 3 to 5, wherein the temperature of the sintered body in step S5 is increased to 900 ℃ at first, and the temperature is maintained for 30-40min, and then increased to 1300 ℃ at 1200 ℃ for 2-3 h.
10. The method as claimed in any one of claims 3 to 5, wherein the two-stage aging treatment in step S5 includes a first stage aging treatment and a second stage aging treatment, 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 ℃.
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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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| 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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