WO2017107248A1 - 一种提高烧结钕铁硼磁体磁性能的方法 - Google Patents

一种提高烧结钕铁硼磁体磁性能的方法 Download PDF

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WO2017107248A1
WO2017107248A1 PCT/CN2016/000378 CN2016000378W WO2017107248A1 WO 2017107248 A1 WO2017107248 A1 WO 2017107248A1 CN 2016000378 W CN2016000378 W CN 2016000378W WO 2017107248 A1 WO2017107248 A1 WO 2017107248A1
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sintered ndfeb
ndfeb magnet
elements
improving
magnet
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PCT/CN2016/000378
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English (en)
French (fr)
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吕向科
王春国
张民
丁勇
杨庆忠
胡依群
汪江峰
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宁波韵升股份有限公司
宁波韵升磁体元件技术有限公司
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Priority to US15/742,531 priority Critical patent/US10741326B2/en
Priority to DE112016005949.3T priority patent/DE112016005949T5/de
Publication of WO2017107248A1 publication Critical patent/WO2017107248A1/zh

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    • 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
    • H01F41/0293—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 diffusion of rare earth elements, e.g. Tb, Dy or Ho, into permanent magnets
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D1/00—General methods or devices for heat treatment, e.g. annealing, hardening, quenching or tempering
    • C—CHEMISTRY; METALLURGY
    • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
    • C23C12/00—Solid state diffusion of at least one non-metal element other than silicon and at least one metal element or silicon into metallic material surfaces
    • C23C12/02—Diffusion in one step
    • 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
    • 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
    • H01F1/0572—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 with a protective layer
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D3/00—Diffusion processes for extraction of non-metals; Furnaces therefor
    • C21D3/02—Extraction of non-metals
    • C21D3/06—Extraction of hydrogen
    • 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
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
    • Y02P10/00—Technologies related to metal processing
    • Y02P10/20—Recycling

Definitions

  • the invention relates to a sintered NdFeB magnet processing technology, in particular to a method for improving the magnetic properties of a sintered NdFeB magnet.
  • Sintered NdFeB permanent magnet materials are widely used in aerospace, aerospace, military and civil applications due to their excellent magnetic properties.
  • energy-saving products such as energy-saving elevators, inverter air conditioners, hybrid vehicles and electric vehicles have emerged. These products have brought huge market demand for NdFeB products.
  • the grain boundary diffusion technique is a method for preparing high-coercivity magnets developed in recent years.
  • the method of adding heavy rare earth elements to the inside of the magnet by the grain boundary diffusion technique is to heat-treat the heavy rare earth elements contained in the surface coating of the magnet. Diffusion into the interior of the magnet along the grain boundary of the magnet, so that the heavy rare earth elements are mainly distributed in the grain boundary phase and the main phase grain epitaxial layer, so that the coercive force can be obviously improved while keeping the residual magnetism hardly reduced, and the heavy rare earth is used. The amount is small and the cost is low.
  • the surface coating of the sintered NdFeB magnet in the grain boundary diffusion technique is usually coated on the surface of the sintered NdFeB magnet by using micron-sized and nano-sized powders such as elemental rare earth, rare earth oxide, rare earth fluoride or rare earth hydride as raw materials. .
  • the rare earth element has poor oxidation resistance, which makes it difficult to produce. Although rare earth oxides and rare earth fluorides have strong antioxidant capacity, they are not easily decomposed into elemental rare earths during diffusion. On the other hand, the oxygen atoms and fluorine atoms contained in rare earth oxides and rare earth fluorides have certain damage to the properties of the magnets.
  • the rare earth hydride phase has better oxidation resistance than the elemental rare earth, and can dehydrogenate to form elemental metal and hydrogen at a certain temperature, thus becoming a ratio An ideal grain boundary diffusion compound.
  • the first method is a method for evaporative condensation disclosed in Chinese Patent No. CN201010241737.4, which obtains a heavy rare earth hydride having a particle size of 10-100 nm, and the heavy rare earth hydride is coated on the surface of the magnet and then subjected to heat treatment.
  • the second method is the Chinese patent of CN201210177327.7 and the Chinese patent No. CN200880000267.3 disclosed in the Chinese Patent No. CN200880000267.3.
  • the heavy rare earth hydride powder is obtained by coating the heavy rare earth hydride powder by hydrogen absorption crushing.
  • the surface of the magnet is subjected to heat treatment to cause the heavy rare earth element to enter the inside of the magnet.
  • the third method is a method of vapor deposition using DyH 2 or TbH 2 as disclosed in Chinese Patent No. CN200780047391.0, which is subjected to heat treatment to cause heavy rare earth elements to enter the inside of the magnet.
  • the nano-scale or micro-scale heavy rare-earth hydride powder used in the first method and the second method is extremely active, and is liable to cause oxidative combustion or even explosion, and it is difficult to meet the protection requirements of the powder in mass production. And once the powder is oxidized, the coercive force increase of the sintered NdFeB magnet will be greatly reduced, causing the problem of poor consistency of the product, and there is also a great safety hazard; in addition, due to the nano- or micro-scale heavy rare earth The hydride powder is extremely oxidizable, so it is difficult to recycle, the utilization rate of the heavy rare earth element is low, and the production cost is high.
  • the third method is safer, but during the evaporation process, the rare earth hydride is randomly distributed inside the equipment, the proportion of the surface of the sintered NdFeB magnet is small, the utilization rate of the heavy rare earth element is low, and the evaporation equipment is additionally used. Expensive, low evaporation efficiency and increased production costs.
  • the technical problem to be solved by the present invention is to provide a method for improving the magnetic properties of a sintered NdFeB magnet.
  • the method is easy to mass-produce, has high efficiency, high product consistency, high utilization rate of heavy rare earth elements, and low production cost. And the security is high.
  • the technical solution adopted by the present invention to solve the above technical problem is: a method for improving the magnetic properties of a sintered NdFeB magnet, firstly coating a raw material containing R, H and X elements on the surface of a sintered NdFeB magnet to form a coating.
  • R is Sc, Y, La, Ce, Pr, Nd, Pm, Sm, Eu, Gd At least one of Tb, Dy, Ho, Er, Tm, Yb, and Lu elements, H is a hydrogen element, and X is at least one of C, O, N, S, B, Cl, and Si elements.
  • the content of the H element is 0.01% to 2% by mass.
  • the content of the H element in the raw material is controlled to be in the range of 0.01% to 2%, and the stability of the raw material can be improved.
  • the content of the X element is 0.01% to 10% by mass.
  • the content of the X element in the raw material is controlled in the range of 0.01% to 10%, which can improve the stability of the raw material, and at the same time, the performance of the sintered NdFeB magnet obtained by the method is remarkably improved.
  • the raw material containing the R, H and X elements further contains other elements capable of chemically reacting with the R element to form an alloy or an intermetallic compound.
  • the product obtained by chemically reacting the R, H and X elements contained in the raw material by the R, H and X elements is present in the raw material.
  • the rare earth element R reacts with the H element and the X element simultaneously to form a compound containing the R, H, and X elements, and the raw material prepared by using the compound can have a high stability of the coating layer.
  • the product obtained by chemically reacting the R, H and X elements contained in the raw material by the hydride of the X element and the R element is present in the raw material.
  • the stability of the rare earth hydride is effectively improved by the X element, which facilitates mass production, improves product consistency, and recycles raw materials.
  • the R element is at least one of the elements of Pr, Nd, Gd, Dy, Tb, and Ho. This method can significantly increase the coercive force of the magnet.
  • the sintered NdFeB magnet has a thickness of less than 15 mm.
  • the rare earth element diffuses uniformly inside the magnet, the coercive force is improved obviously, and the demagnetization curve has a good squareness.
  • the sintered NdFeB magnet having the coating layer is subjected to dehydrogenation treatment before the diffusion treatment, and the temperature of the dehydrogenation treatment is 200 ° C - 900 ° C, and the holding time is 0.1 h - 30 h.
  • the hydrogen content in the coating layer can be effectively controlled by the dehydrogenation treatment, thereby avoiding the destruction of the performance of the magnet by the excessive hydrogen content in the subsequent diffusion treatment.
  • the sintered NdFeB sheet magnet having the coating layer has a mass percentage of hydrogen element in the coating layer of less than 0.2% after dehydrogenation treatment.
  • the hydrogen content of the coating layer is effectively controlled, thereby avoiding the damage of the performance of the hydrogen by the hydrogen during the subsequent diffusion treatment, and ensuring that the performance of the magnet is optimal.
  • the diffusion treatment is carried out at a temperature of 700 ° C - 1000 ° C for 1 h - 30 h.
  • the method ensures that the rare earth element is effectively diffused inside the sintered NdFeB magnet, and is distributed in the grain boundary phase of the sintered NdFeB magnet and the main phase grain epitaxial layer, and the coercive force is obviously improved under the premise that the residual magnetism hardly decreases.
  • the aging treatment is carried out at a temperature of 400 ° C - 600 ° C for 1 h - 10 h.
  • the present invention has an advantage in that a coating layer is formed by coating a raw material containing R, H and X elements on the surface of a sintered NdFeB magnet, and R is at least one of 17 rare earth elements.
  • H is a hydrogen element
  • X is at least one of C, O, N, S, B, Cl, and Si elements
  • a raw material containing R, H, and X elements forming a coating layer is due to R, H, and X elements.
  • Embodiment 1 A method for improving the magnetic properties of a sintered NdFeB magnet, comprising the following steps:
  • the metal ruthenium is treated in a hydrogen-oxygen mixture gas having an oxygen content of 1% to obtain a coarse powder having a hydrogen content of 9416 ppm and an oxygen content of 3174 ppm;
  • the above fine powder raw material is uniformly mixed with anhydrous ethanol, uniformly sprayed on the surface of the sintered NdFeB magnet to form a coating layer, the thickness of the coating layer is 20 ⁇ m, and then dried at 80 ° C;
  • the sintered NdFeB magnet after drying is subjected to dehydrogenation treatment and diffusion treatment in a vacuum environment of 6.0 ⁇ 10 -4 Pa, and then subjected to aging treatment, wherein the temperature of the dehydrogenation treatment is 700 ° C,
  • the hydrogen treatment time was 0.5 h
  • the diffusion treatment temperature was 900 ° C
  • the diffusion treatment time was 16 h
  • the aging treatment temperature was 490 ° C
  • the aging treatment time was 4 h.
  • the sintered NdFeB magnet in this embodiment is obtained by a machining process (cutting) of a large magnet, and its specification (diameter ⁇ height) is ⁇ 10 ⁇ 7 mm, and the large magnet is used in the field of sintered NdFeB processing. , hydrogen crushing, jet milling, forming and sintering processes; the sintered NdFeB magnet comprises the following components: 29.5 wt.% Nd, 0.2 wt.% Dy, 1.0 wt.% B, balance Fe And other trace elements.
  • Embodiment 2 A method for improving the magnetic properties of a sintered NdFeB magnet, comprising the following steps:
  • the first coarse powder is passivated for 24 hours in a nitrogen-oxygen mixture with an oxygen content of 1.5% to obtain a hydrogen content of 9281 ppm, oxygen.
  • a second coarse powder having a content of 3430 ppm and a nitrogen content of 2161 ppm;
  • the sintered NdFeB magnet after drying is subjected to dehydrogenation treatment and diffusion treatment in a vacuum environment of 6.0 ⁇ 10 -4 Pa, and then subjected to aging treatment, wherein the temperature of the dehydrogenation treatment is 680 ° C, The hydrogen treatment time was 1 h, the diffusion treatment temperature was 850 ° C, the diffusion treatment time was 12 h, the aging treatment temperature was 500 ° C, and the aging treatment time was 4 h.
  • the sintered NdFeB magnet in this embodiment is obtained by mechanical processing (cutting) of a large magnet, and its specification (diameter ⁇ height) is ⁇ 10 ⁇ 5 mm, and the large magnet is made of medium-speed coagulation casting in the field of NdFeB processing.
  • the process of hydrogen crushing, jet milling, forming and sintering; the sintered NdFeB magnet comprises the following components: 29.5 wt.% of Nd, 0.2 wt.% of Dy, 1.0 wt.% of B, and the balance of Fe and Other trace elements.
  • Embodiment 3 A method for improving the magnetic properties of a sintered NdFeB magnet, comprising the following steps:
  • the first coarse powder is passivated in air for 24 h to obtain a second coarse powder having a hydrogen content of 5154 ppm, an oxygen content of 7208 ppm, and a nitrogen content of 1140 ppm;
  • the sintered NdFeB magnet after drying is subjected to dehydrogenation treatment and diffusion treatment in a vacuum environment with a pressure of 6.0 ⁇ 10 -4 Pa, and then subjected to aging treatment, wherein the temperature of the dehydrogenation treatment is 710 ° C,
  • the hydrogen treatment time was 2 h
  • the diffusion treatment temperature was 900 ° C
  • the diffusion treatment time was 8 h
  • the aging treatment temperature was 510 ° C
  • the aging treatment time was 4 h.
  • the sintered NdFeB magnet in this embodiment is obtained by a machining process (cutting) of a large magnet, and its specification (diameter ⁇ height) is ⁇ 10 ⁇ 7 mm, and the large magnet is used in the field of sintered NdFeB processing. , hydrogen crushing, jet milling, forming and sintering processes; the sintered NdFeB magnet comprises the following components: 29.5 wt.% Nd, 0.2 wt.% Dy, 1.0 wt.% B, balance Fe And other trace elements.
  • Embodiment 4 A method for improving the magnetic properties of a sintered NdFeB magnet, comprising the following steps:
  • the strontium iron alloy is treated in a hydrogen-oxygen mixed gas having an oxygen content of 0.5% to obtain a hydrogen content of 9861 ppm. a coarse powder having an oxygen content of 2786 ppm;
  • the coarse powder was ball milled for 8 hours to obtain a fine powder material having a specific surface area and an average particle size of 1.58 ⁇ m;
  • the above fine powder raw material is uniformly mixed with anhydrous ethanol, uniformly sprayed on the surface of the sintered NdFeB magnet to form a coating layer, the thickness of the coating layer is 20 ⁇ m, and then dried at 80 ° C;
  • the sintered NdFeB magnet after drying is subjected to dehydrogenation treatment and diffusion treatment in a vacuum environment of 6.0 ⁇ 10 -4 Pa, followed by aging treatment; the temperature of dehydrogenation treatment is 650 ° C, dehydrogenation treatment The time was 3 h, the diffusion treatment temperature was 950 ° C, the diffusion treatment time was 20 h; the aging treatment temperature was 480 ° C, and the aging treatment time was 4 h.
  • the sintered NdFeB magnet in this embodiment is obtained by mechanical processing (cutting) of a large magnet, and its specification (diameter ⁇ height) is ⁇ 10 ⁇ 9 mm, and the large magnet is made of medium-speed coagulation casting in the field of NdFeB processing.
  • the process of hydrogen crushing, jet milling, forming and sintering; the sintered NdFeB magnet comprises the following components: 29.5 wt.% of Nd, 0.2 wt.% of Dy, 1.0 wt.% of B, and the balance of Fe and Other trace elements.
  • Embodiment 5 A method for improving the magnetic properties of a sintered NdFeB magnet, comprising the following steps:
  • the first coarse powder is passivated in a nitrogen-oxygen mixture gas having an oxygen content of 1% for 24 hours to obtain a second coarse powder having a hydrogen content of 9538 ppm, an oxygen content of 3269 ppm, and a nitrogen content of 3290 ppm;
  • the sintered NdFeB magnet after drying is subjected to dehydrogenation treatment and diffusion treatment in a vacuum environment of 6.0 ⁇ 10 -4 Pa, followed by aging treatment; the temperature of dehydrogenation treatment is 750 ° C, dehydrogenation treatment The time was 0.3 h, the diffusion treatment temperature was 800 ° C, the diffusion treatment time was 6 h; the aging treatment temperature was 500 ° C, and the aging treatment time was 4 h.
  • the sintered NdFeB magnet in this embodiment is obtained by a machining process (cutting) of a large magnet, and its specification (diameter ⁇ height) is ⁇ 10 ⁇ 3 mm, and the large magnet is made of medium-speed coagulation casting in the field of NdFeB processing.
  • the process of hydrogen crushing, jet milling, forming and sintering; the sintered NdFeB magnet comprises the following components: 29.5 wt.% of Nd, 0.2 wt.% of Dy, 1.0 wt.% of B, and the balance of Fe and Other trace elements.
  • the sintered NdFeB magnet obtained by the methods of the first embodiment to the fifth embodiment two of each embodiment were selected, and the sintered NdFeB magnets were respectively identified as test samples 1-1, 1-2, 2- 1, 2-1, 3-1, 3-2, 4-1, 4-2 5-1, 5-2, the sintered NdFeB magnet before the coating treatment was identified as the original sample.
  • the original sample and the test sample of the above embodiment were respectively tested for performance by using a permanent magnet material measuring B-H meter.
  • the test data is shown in Table 1 below.
  • Embodiment 6 A method for improving the magnetic properties of a sintered NdFeB magnet, comprising the steps of:
  • the metal crucible is treated in hydrogen to obtain a coarse powder having a hydrogen content of 9590 ppm;
  • the above fine powder and cerium oxide are mixed uniformly at a mass ratio of 9:1 to obtain a fine powder raw material, and the fine powder raw material is uniformly mixed with absolute ethanol and sprayed on the surface of the sintered NdFeB magnet to form a coating layer having a thickness of 20 ⁇ m. And drying at 80 ° C;
  • the sintered NdFeB magnet after drying is subjected to dehydrogenation treatment and diffusion treatment in a vacuum environment of 6.0 ⁇ 10 -4 Pa, followed by aging treatment; the temperature of dehydrogenation treatment is 700 ° C, dehydrogenation treatment The time was 1 h, the diffusion treatment temperature was 950 ° C, the diffusion treatment time was 10 h; the aging treatment temperature was 510 ° C, and the aging treatment time was 4 h.
  • the sintered NdFeB magnet in this embodiment is obtained by mechanical processing (cutting) of a large magnet, and its specification (diameter ⁇ height) is ⁇ 10 ⁇ 7 mm, and the large magnet is made of medium-speed solid-casting piece in the field of NdFeB processing.
  • the process of hydrogen crushing, jet milling, forming and sintering; the sintered NdFeB magnet comprises the following components: 29.5 wt.% of Nd, 0.2 wt.% of Dy, 1.0 wt.% of B, and the balance of Fe and Other trace elements.
  • Embodiment 7 A method for improving the magnetic properties of a sintered NdFeB magnet, comprising the steps of:
  • the first coarse powder is passivated for 24 hours in a nitrogen-oxygen mixed gas having an oxygen content of 1.5% to obtain a second coarse powder having a hydrogen content of 9376 ppm, an oxygen content of 3525 ppm, and a nitrogen content of 3417 ppm;
  • the above fine powder and tantalum nitride are mixed uniformly at a mass ratio of 9:1 to obtain a fine powder raw material, and the fine powder raw material is uniformly mixed with absolute ethanol and sprayed on the surface of the sintered NdFeB magnet to form a coating layer, and the thickness of the coating layer is 20 ⁇ m, and then dried at 80 ° C;
  • the sintered NdFeB magnet after drying is subjected to dehydrogenation treatment and diffusion treatment in a vacuum environment of 6.0 ⁇ 10 -4 Pa, followed by aging treatment; the temperature of dehydrogenation treatment is 660 ° C, dehydrogenation treatment The time was 2 h, the diffusion treatment temperature was 890 ° C, the diffusion treatment time was 18 h; the aging treatment temperature was 500 ° C, and the aging treatment time was 4 h.
  • the sintered NdFeB magnet in this embodiment is obtained by mechanical processing (cutting) of a large magnet, and its specification (diameter ⁇ height) is ⁇ 10 ⁇ 7 mm, and the large magnet is made of medium-speed solid-casting piece in the field of NdFeB processing.
  • the process of hydrogen crushing, jet milling, forming and sintering; the sintered NdFeB magnet comprises the following components: 29.5 wt.% of Nd, 0.2 wt.% of Dy, 1.0 wt.% of B, and the balance of Fe and Other trace elements.
  • Embodiment 8 A method for improving the magnetic properties of a sintered NdFeB magnet, comprising the steps of:
  • the metal ruthenium is treated in a hydrogen-oxygen mixture gas having an oxygen content of 1% to obtain a coarse powder having a hydrogen content of 9891 ppm and an oxygen content of 3157 ppm;
  • the above fine powder and silica are uniformly mixed at a mass ratio of 200:1 to obtain a fine powder raw material, and the fine powder raw material is uniformly sprayed on the surface of the sintered NdFeB magnet to form a coating layer with a thickness of 20 ⁇ m. And drying at 80 ° C;
  • the sintered NdFeB magnet after drying is subjected to dehydrogenation treatment and diffusion treatment in a vacuum environment of 6.0 ⁇ 10 -4 Pa, followed by aging treatment; the temperature of dehydrogenation treatment is 730 ° C, dehydrogenation treatment The time was 0.5 h, the diffusion treatment temperature was 980 ° C, the diffusion treatment time was 6 h; the aging treatment temperature was 500 ° C, and the aging treatment time was 4 h.
  • the sintered NdFeB magnet in this embodiment is obtained by mechanical processing (cutting) of a large magnet, and its specification (diameter ⁇ height) is ⁇ 10 ⁇ 7 mm, and the large magnet is made of medium-speed solid-casting piece in the field of NdFeB processing.
  • the process of hydrogen crushing, jet milling, forming and sintering; the sintered NdFeB magnet comprises the following components: 29.5 wt.% of Nd, 0.2 wt.% Dy, 1.0 wt.% of B, the balance is Fe and other trace elements.
  • each of the two examples was selected, and the sintered NdFeB magnets were respectively identified as test samples 6-1, 6-2, 7- 1, 7-2, 8-1, 8-2, the magnet before coating is identified as the original sample.
  • the original sample and the test sample of the present embodiment were respectively tested for performance by using a permanent magnet material measuring B-H meter, and the test data is shown in Table 2.
  • the sintered NdFeB magnet obtained by the method of the present invention has high remanence, coercive force and maximum magnetic energy product, and has a good squareness.
  • Embodiment 9 A method for improving the magnetic properties of a sintered NdFeB magnet, comprising the steps of:
  • the above fine powder raw material is uniformly mixed with anhydrous ethanol and uniformly sprayed on the surface of the sintered NdFeB magnet to form a coating layer having a thickness of 20 ⁇ m, and then dried at 80 ° C;
  • the sintered NdFeB magnet after drying is subjected to dehydrogenation treatment in a vacuum environment of 6.0 ⁇ 10 -4 Pa; the temperature of dehydrogenation treatment is 700 ° C, and the time of dehydrogenation treatment is 2 h; after dehydrogenation treatment, The magnet containing the coating layer is taken out under vacuum protection to detect the hydrogen content in the coating layer;
  • the sintered NdFeB magnet after the dehydrogenation treatment is subjected to diffusion treatment and aging treatment.
  • Embodiment 10 A method for improving the magnetic properties of a sintered NdFeB magnet, comprising the steps of:
  • the metal crucible is treated in hydrogen to obtain a coarse powder, and the hydrogen content of the coarse powder in the step is detected;
  • the coarse powder is passivated for 24 hours in a nitrogen-oxygen mixture with an oxygen content of 1.5%;
  • the coarse powder was ball milled for 8 hours to obtain a fine powder material having a specific surface area and an average particle size of 1.48 ⁇ m;
  • the sintered NdFeB magnet after drying is subjected to dehydrogenation treatment in a vacuum environment of pressure of 6 ⁇ 10 -4 Pa; the temperature of dehydrogenation treatment is 730 ° C, and the time of dehydrogenation treatment is 1 h; after dehydrogenation treatment, The magnet containing the coating layer was taken out under vacuum protection, and the hydrogen content in the coating layer was detected.
  • the sintered NdFeB magnet after the dehydrogenation treatment is subjected to diffusion treatment and aging treatment.
  • Example 9 The undehydrogenated coating layer in Example 9 is identified as test sample 9-1, the dehydrogenated coating layer is identified as test sample 9-2, and the undehydrogenated coating layer in Example 10 is identified as a test sample. 10-1.
  • the coating after dehydrogenation is identified as test sample 10-2. The measurement was carried out using a hydrogen content tester, and the test data is shown in Table 3.
  • the hydrogen content in the coating layer is far apart before and after the dehydrogenation treatment, thereby reducing the hydrogen content to a reasonable range by dehydrogenation treatment, so as to avoid the magnetic content of the magnet being too high. Can cause adverse effects.

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Abstract

一种提高烧结钕铁硼磁体磁性能的方法，首先将包含R、H和X元素的原料包覆在烧结钕铁硼磁体的表面形成包覆层，然后在真空或惰性气体环境下对具有包覆层的烧结钕铁硼磁体进行扩散处理和时效处理；其中R为Sc、Y、La、Ce、Pr、Nd、Pm、Sm、Eu、Gd、Tb、Dy、Ho、Er、Tm、Yb、Lu元素中的至少一种，H为氢元素，X为C、O、N、S、B、Cl、Si元素中的至少一种；优点是由于R、H和X元素三者的相互作用，包覆层活性较低，暴露于空气中不易氧化，不会产生因原料氧化而引起的产品一致性问题，产品一致性较高且安全性较高，可应用于批量化生产；同时原料稳定性好，便于回收重复利用，因此稀土元素利用率较高，节约了生产成本。

Description

一种提高烧结钕铁硼磁体磁性能的方法 技术领域
本发明涉及一种烧结钕铁硼磁体处理技术，尤其是涉及一种提高烧结钕铁硼磁体磁性能的方法。
背景技术
烧结钕铁硼永磁材料因具有优异的磁性能而广泛应用于航空、航天、军事和民用等领域。近些年，随着国家大力提倡节能环保，节能电梯、变频空调、混合动力汽车和电动汽车等节能产品应运而生，这些产品为钕铁硼产品带来了巨大的市场需求。
经过近30年的发展，烧结钕铁硼永磁材料磁性能得到了很大的提升，剩磁Br实验值1.555T已经达到了理论值1.6T的97％，所以提高烧结钕铁硼永磁材料的剩磁已经很困难，而矫顽力实验值0.82T仅达到理论值6.7T的12％，还有很大的提高空间。因此，探究怎样保持高剩磁同时提高矫顽力成为当下研究的难点与热点。研究发现，用Dy/Tb等重稀土元素置换磁体中部分的Nd，生成各向异性场比主相大的新相(Nd，Dy/Tb)2Fe14B，可以明显提高磁体的矫顽力，但是这会引起磁体剩磁的大幅降低；同时，采用现有常规工艺制备高矫顽力磁体所需的重稀土元素含量高，生产成本高。晶界扩散技术是近年来发展起来的制备高矫顽力磁体的一种方法，采用晶界扩散技术往磁体内部添加重稀土元素的方法是通过热处理工艺使磁体表面涂层中含有的重稀土元素沿着磁体晶界扩散进入磁体内部，使得重稀土元素主要分布在晶界相和主相晶粒外延层，这样可以在保持剩磁几乎不降低的前提下明显提高矫顽力，且重稀土使用量少，成本低。
晶界扩散技术中烧结钕铁硼磁体的表面包覆层通常由单质稀土、稀土氧化物、稀土氟化物或稀土氢化物等微米级及纳米级粉末作为原料包覆在烧结钕铁硼磁体表面形成。单质稀土抗氧化能力差，给生产增加了难度。稀土氧化物、稀土氟化物虽然抗氧化能力强但在扩散过程中不易分解出单质稀土，另一方面稀土氧化物、稀土氟化物中所含有的氧原子和氟原子对磁体性能具有一定的损伤。稀土氢化物相较于单质稀土具有更好的抗氧化能力，而且在一定温度下能够发生脱氢反应生成单质金属和氢气，因而成为一种比 较理想的晶界扩散化合物。
目前，采用重稀土氢化物作为包覆层原料，利用晶界扩散技术提高烧结钕铁硼磁体矫顽力的方法主要有三种。第一种方法是专利号为CN201010241737.4的中国专利中公开的采用蒸发冷凝的方法获得粒度为10-100nm的重稀土氢化物，将此重稀土氢化物包覆在磁体表面，再经过热处理，使得重稀土元素扩散进入磁体内部的方法。第二种方法是专利号为CN201210177327.7的中国专利和专利号为CN200880000267.3的中国专利中公布的采用吸氢破碎的方法获得重稀土氢化物粉末后使该重稀土氢化物粉末包覆于磁体表面，经过热处理使得重稀土元素进入磁体内部的方法。第三种方法是专利号为CN200780047391.0的中国专利中公开的采用DyH2或TbH2进行蒸镀的方法，经热处理使得重稀土元素进入磁体内部。
以上三种方法中，第一种方法和第二种方法使用的纳米级或微米级重稀土氢化物粉末活性极高，极易导致氧化燃烧甚至爆炸，批量化生产中难以满足该粉末的防护要求，而且一旦粉末氧化，对烧结钕铁硼磁体的矫顽力提升幅度就会大幅降低，引起产品的一致性差的问题，同时也存在极大的安全隐患；另外，由于纳米级或微米级重稀土氢化物粉末极易氧化，因此难以回收利用，重稀土元素利用率低，生产成本高。第三种方法安全性较高，但是在蒸镀的过程中，稀土氢化物在设备内部随机分布，附着在烧结钕铁硼磁体表面的比例少，重稀土元素的利用率低，另外蒸镀设备昂贵，蒸镀效率低，增加生产成本。
发明内容
本发明所要解决的技术问题是提供一种提高烧结钕铁硼磁体磁性能的方法，该方法易于进行批量化生产，效率高，产品一致性高，重稀土元素的利用率高，生产成本低，而且安全性高。
本发明解决上述技术问题所采用的技术方案为：一种提高烧结钕铁硼磁体磁性能的方法，首先将包含R、H和X元素的原料包覆在烧结钕铁硼磁体的表面形成包覆层，然后在真空或惰性气体环境下对具有包覆层的烧结钕铁硼磁体进行扩散处理和时效处理；其中R为Sc、Y、La、Ce、Pr、Nd、Pm、Sm、Eu、Gd、Tb、Dy、Ho、Er、Tm、Yb、Lu元素中的至少一种，H为氢元素，X为C、O、N、S、B、Cl、Si元素中的至少一种。
所述的包含R、H和X元素的原料中，所述的H元素的含量按质量百分比为0.01％-2％。该方法中，将原料中H元素的含量控制在0.01％-2％范围内，可提高原料的稳定性。
所述的包含R、H和X元素的原料中，所述的X元素的含量按质量百分比为0.01％-10％。该方法中，将原料中X元素的含量控制在0.01％-10％范围内，可提高原料的稳定性，同时，本方法得到的烧结钕铁硼磁体的性能提升显著。
所述的包含R、H和X元素的原料中还包含有能与所述的R元素发生化学反应形成合金或金属间化合物的其他元素。
所述的原料中含有的R、H和X元素通过R、H和X元素三者混合发生化学反应后得到的产物存在于所述的原料中。该方法中，稀土元素R与H元素、X元素同时发生反应，生成包含R、H、X元素的化合物，采用该化合物制备的原料可以使包覆层具有较高的稳定性。
所述的原料中含有的R、H和X元素通过X元素与R元素的氢化物发生化学反应后得到的产物存在于所述的原料中。该方法中，通过X元素来有效改善稀土氢化物的稳定性，便于批量化生产，提高产品一致性和原料的回收利用。
所述的R元素为Pr、Nd、Gd、Dy、Tb和Ho元素中的至少一种。该方法可显著提高磁体的矫顽力。
所述的烧结钕铁硼磁体的厚度小于15mm。该方法中，稀土元素在磁体内部扩散均匀，矫顽力提升明显，退磁曲线具有较好的方形度。
所述的具有包覆层的烧结钕铁硼磁体在进行扩散处理前，先进行脱氢处理，所述的脱氢处理的温度为200℃-900℃，保温时间为0.1h-30h。该方法中，通过脱氢处理可有效控制包覆层中的氢含量，从而避免后续扩散处理时氢含量过高对磁体性能的破坏。
所述的具有包覆层的烧结钕铁硼薄片磁体在进行脱氢处理后，其包覆层中氢元素的质量百分比含量小于0.2％。该方法中有效控制包覆层的氢含量，从而避免后续扩散处理时氢对磁体性能的损伤，保证磁体性能达到最优。
所述的扩散处理为在温度700℃-1000℃条件下保温1h-30h。该方法保证稀土元素在烧结钕铁硼磁体内部进行有效扩散，分布在烧结钕铁硼磁体的晶界相和主相晶粒外延层，在剩磁几乎不降低的前提下明显提高矫顽力。
所述的时效处理为在温度400℃-600℃条件下保温1h-10h。
与现有技术相比，本发明的优点在于通过将包含R、H和X元素的原料包覆在烧结钕铁硼磁体的表面形成包覆层，R为17种稀土元素中的至少一种，H为氢元素、X为C、O、N、S、B、Cl和Si元素中的至少一种，形成包覆层的包含R、H和X元素的原料由于R、H和X元素三者的相互作用，其活性较低，暴露于空气中不易氧化，不会产生因原料氧化而引起的产品一致性问题，产品一致性较高且安全性较高，可应用于批量化生产；同时由于包含R、H和X元素的原料稳定性好，便于回收重复利用，因此稀土元素利用率高，节约了生产成本。
具体实施方式
以下结合实施例对本发明作进一步详细描述。
实施例一：一种提高烧结钕铁硼磁体磁性能的方法，包括以下步骤：
①将金属铽在氧含量为1％的氢氧混合气中进行处理，得到氢含量为9416ppm，氧含量为3174ppm的粗粉；
②对粗粉进行球磨，时间为8h，得到比表面积平均粒度为1.51μm的细粉原料；
③将上述细粉原料与无水乙醇混合均匀，均匀喷涂于烧结钕铁硼磁体表面形成包覆层，包覆层厚度为20μm，再在80℃条件下进行烘干处理；
④烘干后的烧结钕铁硼磁体在压力为6.0×10-4Pa的真空环境中依次进行脱氢处理和扩散处理，之后再进行时效处理，其中，脱氢处理的温度为700℃，脱氢处理的时间为0.5h，扩散处理的温度为900℃，扩散处理的时间为16h；时效处理的温度为490℃，时效处理的时间为4h。
本实施例中的烧结钕铁硼磁体由大块磁体经过机械加工工艺(切割)获得，其规格(直径×高度)为Φ10×7mm，大块磁体采用烧结钕铁硼加工领域中速凝铸片、氢碎、气流磨、成型和烧结等工艺所得；该烧结钕铁硼磁体包含以下组分：29.5wt.％的Nd，0.2wt.％的Dy，1.0wt.％的B，余量为Fe及其他微量元素。
实施例二：一种提高烧结钕铁硼磁体磁性能的方法，包括以下步骤：
①将金属镝在氢气中进行处理，得到第一粗粉；
②第一粗粉在氧含量为1.5％的氮氧混合气中钝化24h，得到氢含量为9281ppm，氧 含量为3430ppm，氮含量为2161ppm的第二粗粉；
③对第二粗粉进行球磨，时间为8h，得到比表面积平均粒度为1.45μm的细粉原料；
④将上述细粉原料与无水乙醇混合均匀，均匀喷涂于烧结钕铁硼磁体表面形成包覆层，包覆层厚度为20μm，再在80℃条件下进行烘干处理；
⑤烘干后的烧结钕铁硼磁体在压力为6.0×10-4Pa的真空环境中依次进行脱氢处理和扩散处理，之后再进行时效处理，其中，脱氢处理的温度为680℃，脱氢处理的时间为1h，扩散处理的温度为850℃，扩散处理的时间为12h；时效处理的温度为500℃，时效处理的时间为4h。
本实施例中的烧结钕铁硼磁体由大块磁体经过机械加工工艺(切割)获得，其规格(直径×高度)为Φ10×5mm，大块磁体采用钕铁硼加工领域中速凝铸片、氢碎、气流磨、成型和烧结等工艺所得；该烧结钕铁硼磁体包含以下组分：29.5wt.％的Nd，0.2wt.％的Dy，1.0wt.％的B，余量为Fe及其他微量元素。
实施例三：一种提高烧结钕铁硼磁体磁性能的方法，包括以下步骤：
①将金属镝在氢气中进行处理，得到第一粗粉；
②第一粗粉在空气中钝化24h，得到氢含量为5154ppm，氧含量为7208ppm，氮含量为1140ppm的第二粗粉；
③对第二粗粉进行球磨，时间为8h，得到比表面积平均粒度为1.49μm的细粉原料；
④将上述细粉原料与无水乙醇混合均匀，均匀喷涂于烧结钕铁硼磁体表面形成包覆层，包覆层厚度为20μm，再在80℃条件下进行烘干处理；
⑤烘干后的烧结钕铁硼磁体在压力为6.0×10-4Pa的真空环境中依次进行脱氢处理和扩散处理，之后再进行时效处理，其中，脱氢处理的温度为710℃，脱氢处理的时间为2h，扩散处理的温度为900℃，扩散处理的时间为8h；时效处理的温度为510℃，时效处理的时间为4h。
本实施例中的烧结钕铁硼磁体由大块磁体经过机械加工工艺(切割)获得，其规格(直径×高度)为Φ10×7mm，大块磁体采用烧结钕铁硼加工领域中速凝铸片、氢碎、气流磨、成型和烧结等工艺所得；该烧结钕铁硼磁体包含以下组分：29.5wt.％的Nd，0.2wt.％的Dy，1.0wt.％的B，余量为Fe及其他微量元素。
实施例四：一种提高烧结钕铁硼磁体磁性能的方法，包括以下步骤：
①将镝铁合金在氧含量为0.5％的氢氧混合气中进行处理，得到氢含量为9861ppm， 氧含量为2786ppm的粗粉；
②对粗粉进行球磨，时间为8h，得到比表面积平均粒度为1.58μm的细粉原料；
③将上述细粉原料与无水乙醇混合均匀，均匀喷涂于烧结钕铁硼磁体表面形成包覆层，包覆层厚度为20μm，再在80℃条件下进行烘干处理；
④烘干后的烧结钕铁硼磁体在压力为6.0×10-4Pa的真空环境中依次进行脱氢处理和扩散处理，之后再进行时效处理；脱氢处理的温度为650℃，脱氢处理的时间为3h，扩散处理的温度为950℃，扩散处理的时间为20h；时效处理的温度为480℃，时效处理的时间为4h。
本实施例中的烧结钕铁硼磁体由大块磁体经过机械加工工艺(切割)获得，其规格(直径×高度)为Φ10×9mm，大块磁体采用钕铁硼加工领域中速凝铸片、氢碎、气流磨、成型和烧结等工艺所得；该烧结钕铁硼磁体包含以下组分：29.5wt.％的Nd，0.2wt.％的Dy，1.0wt.％的B，余量为Fe及其他微量元素。
实施例五：一种提高烧结钕铁硼磁体磁性能的方法，包括以下步骤：
①将镨铜合金在氢气中进行处理，得到第一粗粉；
②第一粗粉在氧含量为1％的氮氧混合气中钝化24h，得到氢含量为9538ppm，氧含量为3269ppm，氮含量为3290ppm的第二粗粉；
③对第二粗粉进行球磨，时间为8h，得到比表面积平均粒度为1.67μm的细粉原料；
④将上述细粉原料与无水乙醇混合均匀，均匀喷涂于烧结钕铁硼磁体表面形成包覆层，包覆层厚度为20μm，再在80℃条件下进行烘干处理；
⑤烘干后的烧结钕铁硼磁体在压力为6.0×10-4Pa的真空环境中依次进行脱氢处理和扩散处理，之后再进行时效处理；脱氢处理的温度为750℃，脱氢处理的时间为0.3h，扩散处理的温度为800℃，扩散处理的时间为6h；时效处理的温度为500℃，时效处理的时间为4h。
本实施例中的烧结钕铁硼磁体由大块磁体经过机械加工工艺(切割)获得，其规格(直径×高度)为Φ10×3mm，大块磁体采用钕铁硼加工领域中速凝铸片、氢碎、气流磨、成型和烧结等工艺所得；该烧结钕铁硼磁体包含以下组分：29.5wt.％的Nd，0.2wt.％的Dy，1.0wt.％的B，余量为Fe及其他微量元素。
采用以上实施例一～实施例五的方法得到的烧结钕铁硼磁体中，每个实施例选取两个，将这些烧结钕铁硼磁体分别标识为测试样1-1、1-2、2-1、2-1、3-1、3-2、4-1、4-2、 5-1、5-2，将包覆处理前的烧结钕铁硼磁体标识为原始样。采用永磁材料测量B-H仪对上述实施例的原始样和测试样分别进行性能测试，测试数据如下表1所示。
表1实施例一～实施例五原始样和测试样的磁性能
Figure PCTCN2016000378-appb-000001
实施例六：一种提高烧结钕铁硼磁体磁性能的方法，包括以下步骤：
①将金属铽在氢气中进行处理，得到氢含量为9590ppm的粗粉；
②对粗粉进行球磨，时间为8h，得到比表面积平均粒度为1.54μm的细粉；
③将上述细粉和氧化铽按质量比9∶1混合均匀得到细粉原料，细粉原料与无水乙醇混合均匀后喷涂于烧结钕铁硼磁体表面形成包覆层，包覆层厚度为20μm，再在80℃条件下进行烘干处理；
④烘干后的烧结钕铁硼磁体在压力为6.0×10-4Pa的真空环境中依次进行脱氢处理和扩散处理，之后再进行时效处理；脱氢处理的温度为700℃，脱氢处理的时间为1h，扩散处理的温度为950℃，扩散处理的时间为10h；时效处理的温度为510℃，时效处理的时间为4h。
本实施例中的烧结钕铁硼磁体由大块磁体经过机械加工工艺(切割)获得，其规格(直径×高度)为Φ10×7mm，大块磁体采用钕铁硼加工领域中速凝铸片、氢碎、气流磨、成型和烧结等工艺所得；该烧结钕铁硼磁体包含以下组分：29.5wt.％的Nd，0.2wt.％的Dy，1.0wt.％的B，余量为Fe及其他微量元素。
实施例七：一种提高烧结钕铁硼磁体磁性能的方法，包括以下步骤：
①将金属铽在氢气中进行处理，得到第一粗粉；
②第一粗粉在氧含量为1.5％的氮氧混合气中钝化24h，得到氢含量为9378ppm，氧含量为3525ppm，氮含量为3417ppm的第二粗粉；
③对第二粗粉进行球磨，时间为8h，得到比表面积平均粒度为1.41μm的细粉；
④将上述细粉和氮化铽按质量比9∶1混合均匀得到细粉原料，细粉原料与无水乙醇混合均匀后喷涂于烧结钕铁硼磁体表面形成包覆层，包覆层厚度为20μm，再在80℃条件下进行烘干处理；
⑤烘干后的烧结钕铁硼磁体在压力为6.0×10-4Pa的真空环境中依次进行脱氢处理和扩散处理，之后再进行时效处理；脱氢处理的温度为660℃，脱氢处理的时间为2h，扩散处理的温度为890℃，扩散处理的时间为18h；时效处理的温度为500℃，时效处理的时间为4h。
本实施例中的烧结钕铁硼磁体由大块磁体经过机械加工工艺(切割)获得，其规格(直径×高度)为Φ10×7mm，大块磁体采用钕铁硼加工领域中速凝铸片、氢碎、气流磨、成型和烧结等工艺所得；该烧结钕铁硼磁体包含以下组分：29.5wt.％的Nd，0.2wt.％的Dy，1.0wt.％的B，余量为Fe及其他微量元素。
实施例八：一种提高烧结钕铁硼磁体磁性能的方法，包括以下步骤：
①将金属铽在氧含量为1％的氢氧混合气中进行处理，得到氢含量为9891ppm，氧含量为3157ppm的粗粉；
②对粗粉进行球磨，时间为8h，得到比表面积平均粒度为1.57μm的细粉；
③将上述细粉和二氧化硅按质量比200∶1混合均匀得到细粉原料，细粉原料与无水乙醇混合均匀喷涂于烧结钕铁硼磁体表面形成包覆层，包覆层厚度为20μm，再在80℃条件下进行烘干处理；
④烘干后的烧结钕铁硼磁体在压力为6.0×10-4Pa的真空环境中依次进行脱氢处理和扩散处理，之后再进行时效处理；脱氢处理的温度为730℃，脱氢处理的时间为0.5h，扩散处理的温度为980℃，扩散处理的时间为6h；时效处理的温度为500℃，时效处理的时间为4h。
本实施例中的烧结钕铁硼磁体由大块磁体经过机械加工工艺(切割)获得，其规格(直径×高度)为Φ10×7mm，大块磁体采用钕铁硼加工领域中速凝铸片、氢碎、气流磨、成型和烧结等工艺所得；该烧结钕铁硼磁体包含以下组分：29.5wt.％的Nd，0.2wt.％的 Dy，1.0wt.％的B，余量为Fe及其他微量元素。
采用以上实施例六～实施例八的方法得到的烧结钕铁硼磁体中，每个实施例选取两个，将这些烧结钕铁硼磁体分别标识为测试样6-1、6-2、7-1、7-2、8-1、8-2，将包覆前的磁体标识为原始样。采用永磁材料测量B-H仪对本实施例的原始样和测试样分别进行性能测试，测试数据如表2所示。
表2实施例六～实施例八原始样和测试样的磁性能
Figure PCTCN2016000378-appb-000002
分析上述所有实施例可知，本发明的方法得到的烧结钕铁硼磁体具有较高的剩磁、矫顽力和最大磁能积，并且方形度较好。
实施例九：一种提高烧结钕铁硼磁体磁性能的方法，包括以下步骤：
①将金属铽在氧含量为1％的氢氧混合气中进行处理，得到粗粉，检测此步骤中粗粉中的氢含量；
②对粗粉进行球磨，时间为8h，得到比表面积平均粒度为1.51μm的细粉原料；
③将上述细粉原料与无水乙醇混合均匀后均匀喷涂于烧结钕铁硼磁体表面形成包覆层，包覆层厚度为20μm，再在80℃条件下进行烘干处理；
④烘干后的烧结钕铁硼磁体在压力为6.0×10-4Pa的真空环境中进行脱氢处理；脱氢处理的温度为700℃，脱氢处理的时间为2h；脱氢处理后，在真空保护下取出含包覆层的磁体，检测包覆层中的氢含量；
⑤将脱氢处理后的烧结钕铁硼磁体进行扩散处理和时效处理。
实施例十：一种提高烧结钕铁硼磁体磁性能的方法，包括以下步骤：
①将金属镝在氢气中进行处理，得到粗粉，检测此步骤中粗粉的氢含量；
②粗粉在氧含量为1.5％的氮氧混合气中钝化24h；
③对粗粉进行球磨，时间为8h，得到比表面积平均粒度为1.48μm的细粉原料；
④将上述细粉原料与无水乙醇混合均匀后均匀喷涂于烧结钕铁硼磁体表面形成包覆层，包覆层厚度为20μm，再在80℃条件下进行烘干处理；
⑤烘干后的烧结钕铁硼磁体在压力为6×10-4Pa的真空环境中进行脱氢处理；脱氢处理的温度为730℃，脱氢处理的时间为1h；脱氢处理后，在真空保护下取出含包覆层的磁体，检测包覆层中的氢含量。
⑥将脱氢处理后的烧结钕铁硼磁体进行扩散处理和时效处理。
将实施例九中未脱氢的包覆层标识为测试样9-1、脱氢后的包覆层标识为测试样9-2，实施例十中未脱氢的包覆层标识为测试样10-1、脱氢后的包覆层标识为测试样10-2。采用氢含量测试仪进行测定，测试数据如表3所示。
表3未脱氢测试样和脱氢测试样的氢含量
名称 氢含量(ppm)
测试样9-1 9851
测试样9-2 54
测试样10-1 9328
测试样10-2 41
分析上述实施例九和实施例十可知，包覆层中的氢含量在脱氢处理前后相差甚远，由此通过脱氢处理使氢含量降低到合理范围内，以免氢含量过高对磁体磁性能造成不良影响。

Claims (13)

  1. 一种提高烧结钕铁硼磁体磁性能的方法，其特征在于首先将包含R、H和X元素的原料包覆在烧结钕铁硼磁体的表面形成包覆层，然后在真空或惰性气体环境下对具有包覆层的烧结钕铁硼磁体进行扩散处理和时效处理；其中R为Sc、Y、La、Ce、Pr、Nd、Pm、Sm、Eu、Gd、Tb、Dy、Ho、Er、Tm、Yb、Lu元素中的至少一种，H为氢元素，X为C、O、N、S、B、Cl、Si元素中的至少一种。
  2. 根据权利要求1所述的一种提高烧结钕铁硼磁体性能的方法，其特征在于所述的包含R、H和X元素的原料中，所述的H元素的含量按质量百分比为0.01％-2％。
  3. 根据权利要求1所述的一种提高烧结钕铁硼磁体性能的方法，其特征在于所述的包含R、H和X元素的原料中，所述的X元素的含量按质量百分比为0.01％-10％。
  4. 根据权利要求1所述的一种提高烧结钕铁硼磁体磁性能的方法，其特征在于所述的包含R、H和X元素的原料中还包含有能与所述的R元素发生化学反应形成合金或金属间化合物的其他元素。
  5. 根据权利要求1所述的一种提高烧结钕铁硼磁体磁性能的方法，其特征在于所述的原料中含有的R、H和X元素通过R、H和X元素三者混合发生化学反应后得到的产物存在于所述的原料中。
  6. 根据权利要求1所述的一种提高烧结钕铁硼磁体磁性能的方法，其特征在于所述的原料中含有的R、H和X元素通过X元素与R元素的氢化物发生化学反应后得到的产物存在于所述的原料中。
  7. 根据权利要求1所述的一种提高烧结钕铁硼磁体磁性能的方法，其特征在于所述的R元素为Pr、Nd、Gd、Dy、Tb和Ho元素中的至少一种。
  8. 根据权利要求1所述的一种提高烧结钕铁硼磁体磁性能的方法，其特征在于所述的烧结钕铁硼磁体的厚度小于15mm。
  9. 根据权利要求1所述的一种提高烧结钕铁硼磁体磁性能的方法，其特征在于所述的具有包覆层的烧结钕铁硼磁体在进行扩散处理前，先进行脱氢处理，所述的脱氢处理的温度为200℃-900℃，保温时间为0.1h-30h。
  10. 根据权利要求9所述的一种提高烧结钕铁硼磁体磁性能的方法，其特征在于所述的具有包覆层的烧结钕铁硼磁体在进行脱氢处理后，其包覆层中氢元素的质量百分比 含量为0.001％-0.2％。
  11. 根据权利要求9所述的一种提高烧结钕铁硼磁体磁性能的方法，其特征在于所述的脱氢处理的温度为600℃-800℃。
  12. 根据权利要求1所述的一种提高烧结钕铁硼磁体磁性能的方法，其特征在于所述的扩散处理为在温度700℃-1000℃条件下保温1h-30h。
  13. 根据权利要求1所述的一种提高烧结钕铁硼磁体磁性能的方法，其特征在于所述的时效处理为在温度400℃-600℃条件下保温1h-10h。
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CN105632748B (zh) * 2015-12-25 2019-01-11 宁波韵升股份有限公司 一种提高烧结钕铁硼薄片磁体磁性能的方法
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CN111020484B (zh) * 2019-12-26 2022-04-15 厦门钨业股份有限公司 一种含有纳米复合膜的钕铁硼磁体及其制备方法
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Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101615459A (zh) * 2009-04-28 2009-12-30 中国科学院宁波材料技术与工程研究所 提高烧结钕铁硼永磁材料性能的方法
JP2014017480A (ja) * 2012-06-15 2014-01-30 Nissan Motor Co Ltd Ｎｄ−Ｆｅ−Ｂ系磁石の粒界改質方法
CN105489367A (zh) * 2015-12-25 2016-04-13 宁波韵升股份有限公司 一种提高烧结钕铁硼磁体磁性能的方法

Family Cites Families (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US7559996B2 (en) * 2005-07-22 2009-07-14 Shin-Etsu Chemical Co., Ltd. Rare earth permanent magnet, making method, and permanent magnet rotary machine
JP4788427B2 (ja) * 2006-03-23 2011-10-05 日立金属株式会社 Ｒ−Ｆｅ−Ｂ系希土類焼結磁石およびその製造方法
JP4656323B2 (ja) * 2006-04-14 2011-03-23 信越化学工業株式会社 希土類永久磁石材料の製造方法
US8128760B2 (en) 2006-12-21 2012-03-06 Ulvac, Inc. Permanent magnet and method of manufacturing same
EP2133891B1 (en) * 2007-03-30 2017-03-08 TDK Corporation Process for producing magnet
JP5247754B2 (ja) * 2010-03-30 2013-07-24 株式会社日立製作所 磁性材料及びその磁性材料を用いたモータ
CN101908397B (zh) * 2010-07-30 2012-07-04 北京工业大学 稀土氢化物表面涂层处理剂、形成涂层的方法及其应用
CN102747318A (zh) 2012-05-29 2012-10-24 中国科学院宁波材料技术与工程研究所 一种提高烧结稀土-铁-硼永磁材料矫顽力的方法
CN103219146B (zh) * 2013-03-26 2015-06-10 北矿磁材科技股份有限公司 一种还原扩散法提高磁铁性能的方法
JP6331317B2 (ja) * 2013-10-04 2018-05-30 大同特殊鋼株式会社 結合型ＲＦｅＢ系磁石及びその製造方法
CN104134528B (zh) * 2014-07-04 2017-03-01 宁波韵升股份有限公司 一种提高烧结钕铁硼薄片磁体磁性能的方法
CN104599829A (zh) * 2015-01-05 2015-05-06 宁波韵升股份有限公司 一种提高烧结钕铁硼磁体磁性能的方法

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101615459A (zh) * 2009-04-28 2009-12-30 中国科学院宁波材料技术与工程研究所 提高烧结钕铁硼永磁材料性能的方法
JP2014017480A (ja) * 2012-06-15 2014-01-30 Nissan Motor Co Ltd Ｎｄ−Ｆｅ−Ｂ系磁石の粒界改質方法
CN105489367A (zh) * 2015-12-25 2016-04-13 宁波韵升股份有限公司 一种提高烧结钕铁硼磁体磁性能的方法

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