EP4187558A1 - Additive and application thereof, and samarium-cobalt 2: 17 type magnet and preparation method thereof - Google Patents

Additive and application thereof, and samarium-cobalt 2: 17 type magnet and preparation method thereof Download PDF

Info

Publication number
EP4187558A1
EP4187558A1 EP22206155.8A EP22206155A EP4187558A1 EP 4187558 A1 EP4187558 A1 EP 4187558A1 EP 22206155 A EP22206155 A EP 22206155A EP 4187558 A1 EP4187558 A1 EP 4187558A1
Authority
EP
European Patent Office
Prior art keywords
copper
samarium
additive
cobalt
alloy powder
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
EP22206155.8A
Other languages
German (de)
French (fr)
Other versions
EP4187558B1 (en
Inventor
Zhongwei FU
Fuzhong OUYANG
Chang Zhang
Maolin WU
Guoxiong Wang
Dawei Shi
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Fujian Changting Zorr Technology Co Ltd
Xiamen Tungsten Co Ltd
Original Assignee
Fujian Changting Zorr Technology Co Ltd
Xiamen Tungsten Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Fujian Changting Zorr Technology Co Ltd, Xiamen Tungsten Co Ltd filed Critical Fujian Changting Zorr Technology Co Ltd
Publication of EP4187558A1 publication Critical patent/EP4187558A1/en
Application granted granted Critical
Publication of EP4187558B1 publication Critical patent/EP4187558B1/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

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
    • H01F1/012—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials adapted for magnetic entropy change by magnetocaloric effect, e.g. used as magnetic refrigerating material
    • H01F1/015—Metals or alloys
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F1/00—Metallic powder; Treatment of metallic powder, e.g. to facilitate working or to improve properties
    • B22F1/10—Metallic powder containing lubricating or binding agents; Metallic powder containing organic material
    • 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
    • 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
    • H01F1/0555—Alloys characterised by their composition containing rare earth metals and magnetic transition metals, e.g. SmCo5 pressed, sintered or bonded together
    • H01F1/0557—Alloys characterised by their composition containing rare earth metals and magnetic transition metals, e.g. SmCo5 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
    • 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
    • H01F41/0273—Imparting anisotropy
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
    • H01F7/00—Magnets
    • H01F7/02—Permanent magnets [PM]
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F2998/00—Supplementary information concerning processes or compositions relating to powder metallurgy
    • B22F2998/10—Processes characterised by the sequence of their steps
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F2999/00—Aspects linked to processes or compositions used in powder metallurgy

Definitions

  • the present invention relates to an additive and application thereof, and a samarium-cobalt 2: 17 type magnet and a preparation method thereof.
  • the grain boundary structure with copper depletion has a weak domain wall pinning field, which can easily form a reversal magnetization center during demagnetization, thereby reducing the coercivity, squareness, and magnetic energy product of magnets.
  • CN111145973A discloses a preparation method of a magnet containing a Cu grain boundary phase, in which CuO powder is mixed with samarium-cobalt powder, and the mixture is pressed and sintered.
  • the method can improve the coercivity and squareness to certain extents, the oversize micro powder and introduction of a nonmagnetic grain boundary phase cause the reduction of remanence.
  • the micro powder cannot be uniformly dispersed, so that an achieved effect is limited.
  • a copper diffusion method for regulating and controlling grain boundaries has also been reported, but this diffusion method is only effective for sheet samples only, so its use is limited.
  • the present invention provides an additive and application thereof, and a samarium-cobalt 2: 17 type magnet and a preparation method thereof.
  • the preparation method of a Sm 2 Co 17 permanent magnet of the present invention can greatly eliminate adverse effects brought by the phenomenon of copper depletion at grain boundaries without reducing the remanence, thereby improving the coercivity, squareness, and magnetic energy product of products.
  • the present invention adopts the following technical solutions to solve the above technical problem.
  • the present invention provides an additive, which includes the following components by mass percentage: 20-30% of organocopper complex, 0.5-1% of plasticizer, and an organic solvent, and the sum of the mass percentages of the components is 100%, wherein the organocopper complex is an oil-soluble substance, the mass percentage of Cu in the organocopper complex is greater than 10%, and the organocopper complex contains a polar group and/or an alkyl chain having more than 3 C atoms.
  • the organocopper complex may be a conventional oil-soluble organocopper complex in the art, for example, may be completely dissolved in an inert solvent such as toluene and mineral oil.
  • the inert solvent generally refers to a solvent that does not chemically react with the organocopper complex.
  • the polar group in the organocopper complex is one or more of a hydroxyl group, a carboxyl group, an amino group, an ester group, and an amide group.
  • the alkyl chain in the organocopper complex may be a saturated alkyl chain or an unsaturated alkyl chain, and the alkyl chain may be a straight chain or a branched chain.
  • the organocopper complex is one or more of a substituted copper carboxylate complex, a copper carboxylate derivative, a copper thiophosphate complex, copper quinoline, copper hydroxyquinoline, copper phthalate, thiodiazole copper, copper acetylacetonate, and copper acetoacetate.
  • a general formula of the substituted copper carboxylate complex is preferably [RCO 2 ] 2 Cu, where, R is alkyl, alkynyl, cyclo, aryl or heteroaryl; preferably, the substituted copper carboxylate complex is one or more of fatty acid copper having 10 to 22 carbon atoms, copper styrene maleate, copper picolinate, copper 2-pyrazinecarboxylate, copper 2-ethylhexanoate, copper methacrylate, copper thiophene-2-carboxylate, copper methionine, and copper tartrate, and the fatty acid copper having 10 to 22 carbon atoms is preferably one or more of copper oleate, copper linoleate, copper stearate, copper rosinate, copper hexadecanoate, copper palmitate, and copper naphthenate.
  • the copper carboxylate derivative is preferably a copper thiocarboxylate derivative [R'CS 2 ] 2 Cu or a copper selenocarboxylate derivative [R'CSe 2 ] 2 Cu, where, R' includes alkyl and alkyl derivatives; and preferably, the copper carboxylate derivative is copper N,N-di-n-butyldithiocarbamate (Cu(SC(S)N(C 4 H 9 ) 2 ) 2 ) and/or copper N,N-din-butyldiselenocarbamate (Cu(SeC(Se)N(C 4 H 9 ) 2 ) 2 ).
  • the copper thiophosphate complex is preferably a copper complex of a dialkyldithiophosphate, and a general formula of the copper complex of the dialkyldithiophosphate is (RO) 2 P(S)SHM, where, R is alkyl or aryl, and M includes monovalent copper and divalent copper (CuDDP for short); and preferably, the copper thiophosphate complex is one or more of copper dihexyldithiophosphate, copper dibutyldithiophosphate, copper-containing antioxidant T541, and copper-containing antioxidant T542.
  • the copper-containing antioxidant T541 and the copper-containing antioxidant T542 can be purchased from the additive factory of Jinzhou Petrochemical Corporation.
  • the grain diameter of the organocopper complex is less than 10 ⁇ m.
  • the mass percentage of the organocopper complex in the additive is 20%, 22%, 23%, 25%, 27% or 30%.
  • the plasticizer may be a conventional plasticizer in the art, preferably, the plasticizer is a phthalate and/or epoxidized soybean oil, and more preferably, the plasticizer is one or more of dibutyl phthalate, dioctyl phthalate, and epoxidized soybean oil.
  • the organocopper complex can be uniformly dispersed on the surface of powder, agglomeration between the organocopper complexes can be prevented, Cu is uniformly distributed at grain boundaries after the organocopper complex is decomposed, the grain boundary Cu concentration is basically equivalent to the intragranular Cu concentration, and the phenomenon of copper depletion at grain boundaries is avoided.
  • the mass percentage of the plasticizer in the additive is 0.5%, 0.8% or 1%.
  • the organic solvent may be a conventional organic solvent in the art, preferably, the organic solvent is one or more of acetone, toluene, mineral oil, methyl acetate, 120# solvent oil, isooctane, isopropanol, chloroform, and methyl methacrylate, and more preferably, the organic solvent is one or more of 120# solvent oil, toluene, mineral oil, acetone, isooctane, and isopropanol, such as 120# solvent oil, toluene, mineral oil, a mixed solvent of isooctane and isopropanol, and a mixed solvent of acetone and isopropanol.
  • the organic solvent is one or more of acetone, toluene, mineral oil, methyl acetate, 120# solvent oil, isooctane, isopropanol, chloroform, and methyl methacrylate
  • the organic solvent is one or more of 120# solvent oil, tolu
  • the mass percentage of the organic solvent in the additive is 69-79.5%.
  • the additive is composed of 20-30% of organocopper complex, 0.5-1% of plasticizer, and 69-79.5% of organic solvent.
  • the present invention also provides a preparation method of the above additive, which includes the following step: mixing the organocopper complex, the plasticizer, and the organic solvent.
  • the present invention also provides application of the above additive in preparation of a samarium-cobalt magnet.
  • the additive has the effects of lubricating and regulating and controlling grain boundaries of samarium-cobalt magnets, can improve the phenomenon of copper depletion at grain boundaries, and improve the remanence, coercivity, and squareness of magnets.
  • the present invention also provides a preparation method of a samarium-cobalt 2: 17 type magnet, which includes the following steps: mixing samarium-cobalt magnet alloy powder with the above additive, shaping, sintering, and aging.
  • the mass percentage of Cu in the organocopper complex in the samarium-cobalt magnet alloy powder is 0.1-0.2%.
  • raw materials of the samarium-cobalt magnet alloy powder include Sm, Cu, Fe, Zr, and Co.
  • the mass percentage of Sm in the raw materials of the samarium-cobalt magnet alloy powder is 24-26% such as 24%, 25.5%, and 26%.
  • the mass percentage of Cu in the raw materials of the samarium-cobalt magnet alloy powder is 4-6% such as 4%, 5.5%, and 6%.
  • the mass percentage of Fe in the raw materials of the samarium-cobalt magnet alloy powder is 10-20% such as 10%, 17%, 19%, and 20%.
  • the mass percentage of Zr in the raw materials of the samarium-cobalt magnet alloy powder is 2.0-4% such as 2.0%, 3.5%, and 4%.
  • the mass percentage of Co in the raw materials of the samarium-cobalt magnet alloy powder is 45-60% such as 46%, 48%, 51.5%, and 56%.
  • the samarium-cobalt magnet alloy powder is composed of 24% of Sm, 4% of Cu, 17% of Fe, 3.5% of Zr, 51.5% of Co.
  • the samarium-cobalt magnet alloy powder is composed of 25.5% of Sm, 5.5% of Cu, 19% of Fe, 2% of Zr, and 48% of Co.
  • the samarium-cobalt magnet alloy powder is composed of 26% of Sm, 4% of Cu, 10% of Fe, 4% of Zr, and 56% of Co.
  • the samarium-cobalt magnet alloy powder is composed of 24% of Sm, 6% of Cu, 20% of Fe, 4% of Zr, and 46% of Co.
  • the samarium-cobalt magnet alloy powder is obtained by smelting and crushing the raw materials of the samarium-cobalt magnet alloy powder.
  • the smelting is performed by melt-spinning, centrifugal casting or ingot casting.
  • the crushing includes coarse crushing, secondary crushing, and fine crushing, wherein the coarse crushing is preferably Jaw crushing, the secondary crushing is preferably disc milling or crushing with an intermediate crusher, and the fine crushing is preferably jet milling or ball milling.
  • coarse crushing is preferably Jaw crushing
  • secondary crushing is preferably disc milling or crushing with an intermediate crusher
  • fine crushing is preferably jet milling or ball milling.
  • the grain diameter D50 of the samarium-cobalt magnet alloy powder is 4-6 ⁇ m.
  • the samarium-cobalt magnet alloy powder is mixed with the additive, and the mixture is dried to remove most of the solvent, shaped, sintered, and aged.
  • the drying is preferably placing the powder in a dryer and drying at 80°C for 5-10 h such as 5 h, 6 h, 6.5 h, 7 h, 7.5 h, 8 h, and 10 h.
  • the mass percentage of Cu in the organocopper complex in the samarium-cobalt magnet alloy powder is 0.1%, 0.12%, 0.14%, 0.16%, 0.18% or 0.2%, and an addition amount of the additive is determined by the copper content in a selected substance and the solution concentration.
  • the additive is composed of 25% of copper naphthenate, 0.50% of epoxidized soybean oil, and 74.5% of 120# solvent oil; and the mass percentage of the additive in the samarium-cobalt magnet alloy powder is preferably 2.5%.
  • the additive is composed of 30% of copper oleate, 0.50% of epoxidized soybean oil, and 69.5% of 120# solvent oil; and the mass percentage of the additive in the samarium-cobalt magnet alloy powder is preferably 3.3%.
  • the additive is composed of 30% of copper hexadecanoate, 0.50% of dibutyl phthalate, and 69.5% of 120# solvent oil; and the mass percentage of the additive in the samarium-cobalt magnet alloy powder is preferably 3.6%.
  • the additive is composed of 27% of copper N,N-di-n-butyldithiocarbamate, 0.50% of dibutyl phthalate, and 72.5% of toluene; and the mass percentage of the additive in the samarium-cobalt magnet alloy powder is preferably 3.3%.
  • the additive is composed of 25% of copper dihexyldithiophosphate, 0.80% of epoxidized soybean oil, and 74.2% of toluene; and the mass percentage of the additive in the samarium-cobalt magnet alloy powder is preferably 3.4%.
  • the additive is composed of 22% of copper dibutyldithiophosphate, 0.80% of dioctyl phthalate, and 77.2% of mineral oil; and the mass percentage of the additive in the samarium-cobalt magnet alloy powder is preferably 2.4%.
  • the additive is composed of 23% of T541, 0.80% of dioctyl phthalate, and 76.2% of mineral oil; and the mass percentage of the additive in the samarium-cobalt magnet alloy powder is preferably 3.5%.
  • the additive is composed of 20% of copper acetylacetonate, 1% of epoxidized soybean oil, 40% of isooctane, and 39% of isopropanol; and the mass percentage of the additive in the samarium-cobalt magnet alloy powder is preferably 3.7%.
  • the additive is composed of 23% of copper acetoacetate, 1% of epoxidized soybean oil, 40% of acetone, and 36% of isopropanol; and the mass percentage of the additive in the samarium-cobalt magnet alloy powder is preferably 4.4%.
  • the additive is composed of 20% of copper hexadecanoate, 1% of epoxidized soybean oil, 40% of isooctane, and 39% of isopropanol; and the mass percentage of the additive in the samarium-cobalt magnet alloy powder is preferably 8.1%.
  • the additive is composed of 23% of copper oleate, 1% of epoxidized soybean oil, 40% of acetone, and 36% of isopropanol; and the mass percentage of the additive in the samarium-cobalt magnet alloy powder is preferably 8.7%.
  • the shaping operation and conditions may be conventional in the art, and preferably, the shaping is oriented compression shaping performed in a static magnetic field.
  • the magnetic field strength B for shaping is 1.5-2 T.
  • the sintering operation and conditions are conventional in the art.
  • the sintering is performed in an inert atmosphere.
  • the sintering temperature is 1200-1220°C such as 1200°C, 1210°C, 1215°C, and 1220°C.
  • the sintering time is 1-5 h such as 1 h, 3 h, 4 h, and 5 h.
  • solution treatment is performed after sintering.
  • the solution treatment temperature is 1140-1190°C such as 1140°C, 1150°C, 1160°C, and 1190°C.
  • the solution treatment time is 5-40 h such as 5 h, 20 h, 35 h, and 40 h.
  • the aging operation and conditions are conventional in the art.
  • the aging is keeping at 800-900°C (e.g., 810°C, 840°C, 860°C, and 900°C) for 5-20 h (e.g., 5 h, 15 h, and 20 h), cooling to 400°C, and keeping for 5-10 h (e.g., 5 h, 6 h, 7 h, and 10 h).
  • 800-900°C e.g., 810°C, 840°C, 860°C, and 900°C
  • the cooling is performed at a rate of 0.7°C/min.
  • the present invention also provides a samarium-cobalt 2: 17 type magnet, which is prepared by the above preparation method of a samarium-cobalt 2: 17 type magnet.
  • the present invention also provides a samarium-cobalt 2: 17 type magnet, in which the grain boundary Cu concentration is basically equivalent to the intragranular Cu concentration.
  • the grain boundary Cu concentration in the samarium-cobalt 2: 17 type magnet is 3-5.6%
  • the intragranular Cu concentration in the samarium-cobalt 2: 17 type magnet is 3.2-6%
  • the percentage is the percentage of atoms
  • the intragranular and grain boundary Cu concentrations are distributed uniformly.
  • the reagents and materials used in the present invention are all commercially available.
  • the present invention has the following positive progressive effects.
  • the method of using an additive containing an organocopper complex to regulate and control grain boundaries is easy to operate, does not require extra process procedures, and does not have special requirements for the shape and size of a product, so it is suitable for batch production.
  • a finally obtained product has basically equivalent remanence, the coercivity is increased by 5-10 kOe, Hk is increased by 1-4 kOe, and the squareness can reach 60-75%.
  • the smelting was performed by melt-spinning, centrifugal casting or ingot casting; the crushing was coarse crushing, secondary crushing, and fine crushing that were performed in sequence, the coarse crushing was Jaw crushing, the secondary crushing was disc milling or crushing with an intermediate crusher; and the fine crushing was jet milling.
  • the samarium-cobalt magnet alloy powder obtained at step (1) was mixed with an additive shown in Table 2, and the mixture was dried by using a dryer in a 99.99% N 2 atmosphere at 80°C for a period of time shown in Table 1. Then, the mixture was shaped, sintered, and aged. An addition amount of the additive was determined by a set effective addition amount of Cu (the mass percentage of Cu in the organocopper complex in the samarium-cobalt magnet alloy powder) and the solution concentration, see Table 1.
  • the fine crushing was jet milling or ball milling.
  • Oriented compression shaping was performed in a static magnetic field.
  • the magnetic field strength for shaping, the sintering temperature and time, solution treatment temperature and time, and aging operation are shown in Table 3.
  • the cooling in the aging was performed at a rate of 0.7°C/min.
  • Samarium-cobalt magnet alloy powder raw materials and additives were prepared according to the formulas shown in Tables 1 and 2, and other process conditions were the same as those in Example 1 in addition to the operation parameters shown in Table 3.
  • the additives of Contrasts 1 to 4 contained a lubricant and an organic solvent only; the additives of Contrasts 5 to 7 contained an organocopper complex only; and the additive of Contrast 10 contained an organocopper complex and an organic solvent only.
  • the grain boundary Cu concentration is basically equivalent to the intragranular Cu concentration, so that the phenomenon of copper depletion at grain boundaries is avoided.
  • the samples of the examples have basically equivalent remanence, the coercivity is increased by 5-10 kOe, Hk is increased by 1-4 kOe, and the squareness can reach 60-75%.

Landscapes

  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Chemical & Material Sciences (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Inorganic Chemistry (AREA)
  • Manufacturing & Machinery (AREA)
  • Physics & Mathematics (AREA)
  • Electromagnetism (AREA)
  • Hard Magnetic Materials (AREA)
  • Powder Metallurgy (AREA)

Abstract

Disclosed are an additive and application thereof, and a samarium-cobalt 2: 17 type magnet and a preparation method thereof. The additive includes the following components by mass percentage: 20-30% of organocopper complex, 0.5-1% of plasticizer, and an organic solvent, and the sum of the mass percentages of the components is 100%. The organocopper complex is an oil-soluble substance, the mass percentage of Cu in the organocopper complex is greater than 10%, and the organocopper complex contains a polar group and/or an alkyl chain having more than 3 C atoms. The preparation method of a Sm2Co17 permanent magnet of the present invention can greatly eliminate adverse effects brought by the phenomenon of copper depletion at grain boundaries without reducing the remanence, thereby improving the coercivity, squareness, and magnetic energy product of products.

Description

    Field of the Invention
  • The present invention relates to an additive and application thereof, and a samarium-cobalt 2: 17 type magnet and a preparation method thereof.
    • Background of the Invention
  • The phenomenon of copper depletion at grain boundaries commonly occurs in Sm2Co17 permanent magnet materials (also referred to as samarium-cobalt 2: 17 type magnets) and has become an obstacle for the improvement of properties, especially the squareness, of the Sm2Co17 permanent magnet materials. The grain boundary structure with copper depletion has a weak domain wall pinning field, which can easily form a reversal magnetization center during demagnetization, thereby reducing the coercivity, squareness, and magnetic energy product of magnets.
  • The current practice is to improve the phenomenon of copper depletion at grain boundaries by adding micro or nano copper or copper oxide powder directly to jet-milled powder. For example, CN111145973A discloses a preparation method of a magnet containing a Cu grain boundary phase, in which CuO powder is mixed with samarium-cobalt powder, and the mixture is pressed and sintered. Although the method can improve the coercivity and squareness to certain extents, the oversize micro powder and introduction of a nonmagnetic grain boundary phase cause the reduction of remanence. Moreover, the micro powder cannot be uniformly dispersed, so that an achieved effect is limited. In addition, a copper diffusion method for regulating and controlling grain boundaries has also been reported, but this diffusion method is only effective for sheet samples only, so its use is limited.
    • Summary of the Invention
  • In order to solve the defect that in the prior art, the coercivity and squareness are only improved to limited extents and the remanence may be reduced when overcoming the problem of poor magnetic properties, especially low squareness, of Sm2Co17 permanent magnet materials caused by the phenomenon of copper depletion at grain boundaries, the present invention provides an additive and application thereof, and a samarium-cobalt 2: 17 type magnet and a preparation method thereof. The preparation method of a Sm2Co17 permanent magnet of the present invention can greatly eliminate adverse effects brought by the phenomenon of copper depletion at grain boundaries without reducing the remanence, thereby improving the coercivity, squareness, and magnetic energy product of products.
  • The present invention adopts the following technical solutions to solve the above technical problem.
  • The present invention provides an additive, which includes the following components by mass percentage: 20-30% of organocopper complex, 0.5-1% of plasticizer, and an organic solvent, and the sum of the mass percentages of the components is 100%,
    wherein the organocopper complex is an oil-soluble substance, the mass percentage of Cu in the organocopper complex is greater than 10%, and the organocopper complex contains a polar group and/or an alkyl chain having more than 3 C atoms.
  • In the present invention, the organocopper complex may be a conventional oil-soluble organocopper complex in the art, for example, may be completely dissolved in an inert solvent such as toluene and mineral oil. The inert solvent generally refers to a solvent that does not chemically react with the organocopper complex.
  • Preferably, the polar group in the organocopper complex is one or more of a hydroxyl group, a carboxyl group, an amino group, an ester group, and an amide group.
  • The alkyl chain in the organocopper complex may be a saturated alkyl chain or an unsaturated alkyl chain, and the alkyl chain may be a straight chain or a branched chain.
  • Preferably, the organocopper complex is one or more of a substituted copper carboxylate complex, a copper carboxylate derivative, a copper thiophosphate complex, copper quinoline, copper hydroxyquinoline, copper phthalate, thiodiazole copper, copper acetylacetonate, and copper acetoacetate.
  • A general formula of the substituted copper carboxylate complex is preferably [RCO2]2Cu, where, R is alkyl, alkynyl, cyclo, aryl or heteroaryl; preferably, the substituted copper carboxylate complex is one or more of fatty acid copper having 10 to 22 carbon atoms, copper styrene maleate, copper picolinate, copper 2-pyrazinecarboxylate, copper 2-ethylhexanoate, copper methacrylate, copper thiophene-2-carboxylate, copper methionine, and copper tartrate, and the fatty acid copper having 10 to 22 carbon atoms is preferably one or more of copper oleate, copper linoleate, copper stearate, copper rosinate, copper hexadecanoate, copper palmitate, and copper naphthenate.
  • The copper carboxylate derivative is preferably a copper thiocarboxylate derivative [R'CS2]2Cu or a copper selenocarboxylate derivative [R'CSe2]2Cu, where, R' includes alkyl and alkyl derivatives; and preferably, the copper carboxylate derivative is copper N,N-di-n-butyldithiocarbamate (Cu(SC(S)N(C4H9)2)2) and/or copper N,N-din-butyldiselenocarbamate (Cu(SeC(Se)N(C4H9)2)2).
  • The copper thiophosphate complex is preferably a copper complex of a dialkyldithiophosphate, and a general formula of the copper complex of the dialkyldithiophosphate is (RO)2P(S)SHM, where, R is alkyl or aryl, and M includes monovalent copper and divalent copper (CuDDP for short); and preferably, the copper thiophosphate complex is one or more of copper dihexyldithiophosphate, copper dibutyldithiophosphate, copper-containing antioxidant T541, and copper-containing antioxidant T542. The copper-containing antioxidant T541 and the copper-containing antioxidant T542 can be purchased from the additive factory of Jinzhou Petrochemical Corporation.
  • Preferably, the grain diameter of the organocopper complex is less than 10 µm.
  • In the present invention, preferably, the mass percentage of the organocopper complex in the additive is 20%, 22%, 23%, 25%, 27% or 30%.
  • In the present invention, the plasticizer may be a conventional plasticizer in the art, preferably, the plasticizer is a phthalate and/or epoxidized soybean oil, and more preferably, the plasticizer is one or more of dibutyl phthalate, dioctyl phthalate, and epoxidized soybean oil. Through the cooperation of the usage amount of the plasticizer and other components of the additive, the organocopper complex can be uniformly dispersed on the surface of powder, agglomeration between the organocopper complexes can be prevented, Cu is uniformly distributed at grain boundaries after the organocopper complex is decomposed, the grain boundary Cu concentration is basically equivalent to the intragranular Cu concentration, and the phenomenon of copper depletion at grain boundaries is avoided.
  • In the present invention, preferably, the mass percentage of the plasticizer in the additive is 0.5%, 0.8% or 1%.
  • In the present invention, the organic solvent may be a conventional organic solvent in the art, preferably, the organic solvent is one or more of acetone, toluene, mineral oil, methyl acetate, 120# solvent oil, isooctane, isopropanol, chloroform, and methyl methacrylate, and more preferably, the organic solvent is one or more of 120# solvent oil, toluene, mineral oil, acetone, isooctane, and isopropanol, such as 120# solvent oil, toluene, mineral oil, a mixed solvent of isooctane and isopropanol, and a mixed solvent of acetone and isopropanol.
  • In the present invention, preferably, the mass percentage of the organic solvent in the additive is 69-79.5%.
  • In the present invention, preferably, the additive is composed of 20-30% of organocopper complex, 0.5-1% of plasticizer, and 69-79.5% of organic solvent.
  • The present invention also provides a preparation method of the above additive, which includes the following step:
    mixing the organocopper complex, the plasticizer, and the organic solvent.
  • The present invention also provides application of the above additive in preparation of a samarium-cobalt magnet. The additive has the effects of lubricating and regulating and controlling grain boundaries of samarium-cobalt magnets, can improve the phenomenon of copper depletion at grain boundaries, and improve the remanence, coercivity, and squareness of magnets.
  • The present invention also provides a preparation method of a samarium-cobalt 2: 17 type magnet, which includes the following steps: mixing samarium-cobalt magnet alloy powder with the above additive, shaping, sintering, and aging.
  • The mass percentage of Cu in the organocopper complex in the samarium-cobalt magnet alloy powder is 0.1-0.2%.
  • In the present invention, preferably, raw materials of the samarium-cobalt magnet alloy powder include Sm, Cu, Fe, Zr, and Co.
  • Preferably, the mass percentage of Sm in the raw materials of the samarium-cobalt magnet alloy powder is 24-26% such as 24%, 25.5%, and 26%.
  • Preferably, the mass percentage of Cu in the raw materials of the samarium-cobalt magnet alloy powder is 4-6% such as 4%, 5.5%, and 6%.
  • Preferably, the mass percentage of Fe in the raw materials of the samarium-cobalt magnet alloy powder is 10-20% such as 10%, 17%, 19%, and 20%.
  • Preferably, the mass percentage of Zr in the raw materials of the samarium-cobalt magnet alloy powder is 2.0-4% such as 2.0%, 3.5%, and 4%.
  • Preferably, the mass percentage of Co in the raw materials of the samarium-cobalt magnet alloy powder is 45-60% such as 46%, 48%, 51.5%, and 56%.
  • In a preferred embodiment of the present invention, the samarium-cobalt magnet alloy powder is composed of 24% of Sm, 4% of Cu, 17% of Fe, 3.5% of Zr, 51.5% of Co.
  • In a preferred embodiment of the present invention, the samarium-cobalt magnet alloy powder is composed of 25.5% of Sm, 5.5% of Cu, 19% of Fe, 2% of Zr, and 48% of Co.
  • In a preferred embodiment of the present invention, the samarium-cobalt magnet alloy powder is composed of 26% of Sm, 4% of Cu, 10% of Fe, 4% of Zr, and 56% of Co.
  • In a preferred embodiment of the present invention, the samarium-cobalt magnet alloy powder is composed of 24% of Sm, 6% of Cu, 20% of Fe, 4% of Zr, and 46% of Co.
  • Preferably, the samarium-cobalt magnet alloy powder is obtained by smelting and crushing the raw materials of the samarium-cobalt magnet alloy powder.
  • Preferably, the smelting is performed by melt-spinning, centrifugal casting or ingot casting.
  • Preferably, the crushing includes coarse crushing, secondary crushing, and fine crushing, wherein the coarse crushing is preferably Jaw crushing, the secondary crushing is preferably disc milling or crushing with an intermediate crusher, and the fine crushing is preferably jet milling or ball milling.
  • Preferably, the grain diameter D50 of the samarium-cobalt magnet alloy powder is 4-6 µm.
  • Preferably, the samarium-cobalt magnet alloy powder is mixed with the additive, and the mixture is dried to remove most of the solvent, shaped, sintered, and aged. The drying is preferably placing the powder in a dryer and drying at 80°C for 5-10 h such as 5 h, 6 h, 6.5 h, 7 h, 7.5 h, 8 h, and 10 h.
  • In the present invention, preferably, the mass percentage of Cu in the organocopper complex in the samarium-cobalt magnet alloy powder is 0.1%, 0.12%, 0.14%, 0.16%, 0.18% or 0.2%, and an addition amount of the additive is determined by the copper content in a selected substance and the solution concentration.
  • In a preferred embodiment of the present invention, the additive is composed of 25% of copper naphthenate, 0.50% of epoxidized soybean oil, and 74.5% of 120# solvent oil; and the mass percentage of the additive in the samarium-cobalt magnet alloy powder is preferably 2.5%.
  • In a preferred embodiment of the present invention, the additive is composed of 30% of copper oleate, 0.50% of epoxidized soybean oil, and 69.5% of 120# solvent oil; and the mass percentage of the additive in the samarium-cobalt magnet alloy powder is preferably 3.3%.
  • In a preferred embodiment of the present invention, the additive is composed of 30% of copper hexadecanoate, 0.50% of dibutyl phthalate, and 69.5% of 120# solvent oil; and the mass percentage of the additive in the samarium-cobalt magnet alloy powder is preferably 3.6%.
  • In a preferred embodiment of the present invention, the additive is composed of 27% of copper N,N-di-n-butyldithiocarbamate, 0.50% of dibutyl phthalate, and 72.5% of toluene; and the mass percentage of the additive in the samarium-cobalt magnet alloy powder is preferably 3.3%.
  • In a preferred embodiment of the present invention, the additive is composed of 25% of copper dihexyldithiophosphate, 0.80% of epoxidized soybean oil, and 74.2% of toluene; and the mass percentage of the additive in the samarium-cobalt magnet alloy powder is preferably 3.4%.
  • In a preferred embodiment of the present invention, the additive is composed of 22% of copper dibutyldithiophosphate, 0.80% of dioctyl phthalate, and 77.2% of mineral oil; and the mass percentage of the additive in the samarium-cobalt magnet alloy powder is preferably 2.4%.
  • In a preferred embodiment of the present invention, the additive is composed of 23% of T541, 0.80% of dioctyl phthalate, and 76.2% of mineral oil; and the mass percentage of the additive in the samarium-cobalt magnet alloy powder is preferably 3.5%.
  • In a preferred embodiment of the present invention, the additive is composed of 20% of copper acetylacetonate, 1% of epoxidized soybean oil, 40% of isooctane, and 39% of isopropanol; and the mass percentage of the additive in the samarium-cobalt magnet alloy powder is preferably 3.7%.
  • In a preferred embodiment of the present invention, the additive is composed of 23% of copper acetoacetate, 1% of epoxidized soybean oil, 40% of acetone, and 36% of isopropanol; and the mass percentage of the additive in the samarium-cobalt magnet alloy powder is preferably 4.4%.
  • In a preferred embodiment of the present invention, the additive is composed of 20% of copper hexadecanoate, 1% of epoxidized soybean oil, 40% of isooctane, and 39% of isopropanol; and the mass percentage of the additive in the samarium-cobalt magnet alloy powder is preferably 8.1%.
  • In a preferred embodiment of the present invention, the additive is composed of 23% of copper oleate, 1% of epoxidized soybean oil, 40% of acetone, and 36% of isopropanol; and the mass percentage of the additive in the samarium-cobalt magnet alloy powder is preferably 8.7%.
  • In the present invention, the shaping operation and conditions may be conventional in the art, and preferably, the shaping is oriented compression shaping performed in a static magnetic field.
  • Preferably, the magnetic field strength B for shaping is 1.5-2 T.
  • In the present invention, the sintering operation and conditions are conventional in the art.
  • Preferably, the sintering is performed in an inert atmosphere.
  • Preferably, the sintering temperature is 1200-1220°C such as 1200°C, 1210°C, 1215°C, and 1220°C.
  • Preferably, the sintering time is 1-5 h such as 1 h, 3 h, 4 h, and 5 h.
  • In the present invention, preferably, solution treatment is performed after sintering.
  • Preferably, the solution treatment temperature is 1140-1190°C such as 1140°C, 1150°C, 1160°C, and 1190°C.
  • Preferably, the solution treatment time is 5-40 h such as 5 h, 20 h, 35 h, and 40 h.
  • In the present invention, the aging operation and conditions are conventional in the art.
  • Preferably, the aging is keeping at 800-900°C (e.g., 810°C, 840°C, 860°C, and 900°C) for 5-20 h (e.g., 5 h, 15 h, and 20 h), cooling to 400°C, and keeping for 5-10 h (e.g., 5 h, 6 h, 7 h, and 10 h).
  • Preferably, the cooling is performed at a rate of 0.7°C/min.
  • The present invention also provides a samarium-cobalt 2: 17 type magnet, which is prepared by the above preparation method of a samarium-cobalt 2: 17 type magnet.
  • The present invention also provides a samarium-cobalt 2: 17 type magnet, in which the grain boundary Cu concentration is basically equivalent to the intragranular Cu concentration.
  • In the present invention, preferably, the grain boundary Cu concentration in the samarium-cobalt 2: 17 type magnet is 3-5.6%, the intragranular Cu concentration in the samarium-cobalt 2: 17 type magnet is 3.2-6%, the percentage is the percentage of atoms, and the intragranular and grain boundary Cu concentrations are distributed uniformly.
  • On the basis of conforming to common knowledge in the art, the above preferred conditions can be combined arbitrarily to obtain preferred embodiments of the present invention.
  • The reagents and materials used in the present invention are all commercially available.
  • The present invention has the following positive progressive effects.
  • The method of using an additive containing an organocopper complex to regulate and control grain boundaries is easy to operate, does not require extra process procedures, and does not have special requirements for the shape and size of a product, so it is suitable for batch production. Compared to a product prepared by the conventional method, a finally obtained product has basically equivalent remanence, the coercivity is increased by 5-10 kOe, Hk is increased by 1-4 kOe, and the squareness can reach 60-75%.
    • Brief Description of the Drawings
    • Fig. 1 is a comparison curve diagram of magnetic properties of samples of Example 4 and Contrast 4;
    • Fig. 2 is a scanning image of a distributive area of Cu at grain boundaries of the sample of Contrast 4;
    • Fig. 3 is a scanning image of a distributive area of Cu at grain boundaries of the sample of Example 4;
    • Fig. 4 is a line scanning image of the grain boundary Cu concentration in the sample of Contrast 4; and
    • Fig. 5 is a line scanning image of the grain boundary Cu concentration in the sample of Example 4.
    Detailed Description of the Embodiments
  • The present invention will be further described below with reference to examples, but the present invention is not limited to the range of the examples. Experimental methods that do not indicate specific conditions in the following examples follow conventional methods and conditions or product manuals.
    • Example 1
    1. (1) Raw materials of samarium-cobalt magnet alloy powder shown in Table 1 were smelted and crushed to obtain samarium-cobalt magnet alloy powder, and the grain diameter D50 of the samarium-cobalt magnet alloy powder was 4-6 µm.
  • The smelting was performed by melt-spinning, centrifugal casting or ingot casting; the crushing was coarse crushing, secondary crushing, and fine crushing that were performed in sequence, the coarse crushing was Jaw crushing, the secondary crushing was disc milling or crushing with an intermediate crusher; and the fine crushing was jet milling.
  • (2) The samarium-cobalt magnet alloy powder obtained at step (1) was mixed with an additive shown in Table 2, and the mixture was dried by using a dryer in a 99.99% N2 atmosphere at 80°C for a period of time shown in Table 1. Then, the mixture was shaped, sintered, and aged. An addition amount of the additive was determined by a set effective addition amount of Cu (the mass percentage of Cu in the organocopper complex in the samarium-cobalt magnet alloy powder) and the solution concentration, see Table 1.
  • The fine crushing was jet milling or ball milling. Oriented compression shaping was performed in a static magnetic field. The magnetic field strength for shaping, the sintering temperature and time, solution treatment temperature and time, and aging operation are shown in Table 3. The cooling in the aging was performed at a rate of 0.7°C/min. Table 1 Raw materials of samarium-cobalt magnet alloy powders of examples and contrasts
    Samarium-cobalt magnet alloy powder (mass percentage) Mass percentage of additive in samarium-cobalt magnet alloy powder / % Drying time / h
    Sm Cu Fe Zr Co
    Example 1 24 4 17 3.5 balance 2.5 5
    Example 2 24 4 17 3.5 balance 3.3 6
    Example 3 24 4 17 3.5 balance 3.6 7.5
    Example 4 25.5 5.5 19 2 balance 3.3 6
    Example 5 25.5 5.5 19 2 balance 3.4 6.5
    Example 6 25.5 5.5 19 2 balance 2.4 5
    Example 7 26 4 10 4 balance 3.5 7
    Example 8 26 4 10 4 balance 3.7 8
    Example 9 24 6 20 4 balance 4.4 10
    Example 10 26 4 10 4 balance 8.1 8
    Example 11 24 6 20 4 balance 8.7 10
    Contrast 1 24 4 17 3.5 balance 0.4 5
    Contrast 2 24 4 17 3.5 balance 0.3 6
    Contrast 3 24 4 17 3.5 balance 0.4 7.5
    Contrast 4 25.5 5.5 19 2 balance 0.4 6
    Contrast 5 25.5 5.5 19 2 balance 0.14 6.5
    Contrast 6 25.5 5.5 19 2 balance 0.14 5
    Contrast 7 26 4 10 4 balance 0.16 7
    Contrast 8 26 4 10 4 balance 1.6 8
    Contrast 9 24 6 20 4 balance 11 10
    Contrast 10 24 6 20 4 balance 4.4 10
    Table 2 Components of additives of examples and contrasts and mass percentages thereof
    Organocopper complex Plasticizer Solvent Effective addition amount of Cu/%
    Variety Cu content/% Usage amount/% Variety Usage amount/% Variety Usage amount /%
    Example 1 Copper naphthenate 15.7 25 Epoxidized soybean oil 0.5 120# solvent oil balance 0.1
    Example 2 Copper oleate 10 30 Epoxidized soybean oil 0.5 120# solvent oil balance 0.1
    Example 3 Copper hexadecanoate 11.08 30 Dibutyl phthalate 0.5 120# solvent oil balance 0.12
    Example 4 Copper N,N-di-n-butyldithiocarbamate 13.5 27 Dibutyl phthalate 0.5 Toluene balance 0.12
    Example 5 Copper dihexyldithiophosphate 16.5 25 Epoxidized soybean oil 0.8 Toluene balance 0.14
    Example 6 Copper dibutyldithiophosphate 26.2 22 Dioctyl phthalate 0.8 Mineral oil balance 0.14
    Example 7 T541 about 20 23 Dioctyl phthalate 0.8 Mineral oil balance 0.16
    Example 8 Copper acetylacetonate 24.3 20 Epoxidized soybean oil 1 Isooctane 40% 0.18
    Isopropanol balance
    Example 9 Copper acetoacetate 19.7 23 Epoxidized soybean oil 1 Acetone 40% 0.2
    Isopropanol balance
    Example 10 Copper hexadecanoate 11.08 20 Epoxidized soybean oil 1 Isooctane 40% 0.18
    Isopropanol balance
    Example 11 Copper oleate 10 23 Epoxidized soybean oil 1 Acetone 40% 0.2
    Isopropanol balance
    Contrast 1 conventional lubricant (butyl oleate) 0 25 / / 120# solvent oil balance 0
    Contrast 2 conventional lubricant (butyl oleate) 0 30 / / 120# solvent oil balance 0
    Contrast 3 conventional lubricant (methyl decanoate) 0 30 / / 120# solvent oil balance 0
    Contrast 4 conventional lubricant (poly(α-olefin)) 0 27 / / Toluene balance 0
    Contrast 5 Copper dihexyldithiophosphate 16.5 / / / / / 0.14
    Contrast 6 Copper dibutyldithiophosphate 26.2 / / / / / 0.14
    Contrast 7 T541 about 20 / / / / / 0.16
    Contrast 8 Copper acetylacetonate 24.3 13 Epoxidized soybean oil 1 Isooctane 40% 0.05
    Isopropanol balance
    Contrast 9 Copper acetoacetate 19.7 23 Epoxidized soybean oil 1 Acetone 40% 0.5
    Isopropa nol balan ce
    Contrast 10 Copper acetoacetate 19.7 23 / / Acetone 40% 0.2
    Isopropanol balance
    Table 3 Parameters of shaping, sintering, solution treatment, and aging of examples and contrasts
    Magnetic field strength for shaping Sintering Solution Treatment Aging
    Temperature Time Temperature Time
    Example 1 1.5T 1210 3 1160 20 keep at 840°C for 20 h, cool to 400°C, and keep for 6 h
    Example 2 1.5T 1210 3 1160 20 keep at 840°C for 20 h, cool to 400°C, and keep for 6 h
    Example 3 1.5T 1210 3 1160 20 keep at 840°C for 20 h, cool to 400°C, and keep for 6 h
    Example 4 1.5T 1215 4 1150 35 keep at 860°C for 15 h, cool to 400°C, and keep for 7 h
    Example 5 1.5T 1215 4 1150 35 keep at 860°C for 15 h, cool to 400°C, and keep for 7 h
    Example 6 1.5T 1215 4 1150 35 keep at 860°C for 15 h, cool to 400°C, and keep for 7 h
    Example 7 2.0T 1200 1 1190 5 keep at 810°C for 20 h, cool to 400°C, and keep for 10 h
    Example 8 2.0T 1200 1 1190 5 keep at 810°C for 20 h, cool to 400°C, and keep for 10 h
    Example 9 2.0T 1220 5 1140 40 keep at 900°C for 5 h, cool to 400°C, and keep for 5 h
    Example 10 2.0T 1200 1 1190 5 keep at 810°C for 20 h, cool to 400°C, and keep for 10 h
    Example 11 2.0T 1220 5 1140 40 keep at 900°C for 5 h, cool to 400°C, and keep for 5 h
    Contrast 1 1.5T 1210 3 1160 20 keep at 840°C for 20 h, cool to 400°C, and keep for 6 h
    Contrast 2 1.5T 1210 3 1160 20 keep at 840°C for 20 h, cool to 400°C, and keep for 6 h
    Contrast 3 1.5T 1210 3 1160 20 keep at 840°C for 20 h, cool to 400°C, and keep for 6 h
    Contrast 4 1.5T 1215 4 1150 35 keep at 860°C for 15 h, cool to 400°C, and keep for 7 h
    Contrast 5 1.5T 1215 4 1150 35 keep at 860°C for 15 h, cool to 400°C, and keep for 7 h
    Contrast 6 1.5T 1215 4 1150 35 keep at 860°C for 15 h, cool to 400°C, and keep for 7 h
    Contrast 7 2.0T 1200 1 1190 5 keep at 810°C for 20 h, cool to 400°C, and keep for 10 h
    Contrast 8 2.0T 1200 1 1190 5 keep at 810°C for 20 h, cool to 400°C, and keep for 10 h
    Contrast 9 2.0T 1220 5 1140 40 keep at 900°C for 5 h, cool to 400°C, and keep for 5 h
    Contrast 10 2.0T 1220 5 1140 40 keep at 900°C for 5 h, cool to 400°C, and keep for 5 h
    • Examples 2 to 11 and Contrasts 1 to 10
  • Samarium-cobalt magnet alloy powder raw materials and additives were prepared according to the formulas shown in Tables 1 and 2, and other process conditions were the same as those in Example 1 in addition to the operation parameters shown in Table 3.
  • The additives of Contrasts 1 to 4 contained a lubricant and an organic solvent only; the additives of Contrasts 5 to 7 contained an organocopper complex only; and the additive of Contrast 10 contained an organocopper complex and an organic solvent only.
    • Effect Example
  • Magnetic properties, i.e., the remanence Br, the intrinsic coercivity Hcj, a knee point Hk, the squareness Hk/Hcj, and the maximum magnetic energy product (BH)max, of the examples and the contrasts of the present invention were detected by using a pulse magnetic field meter (PFM). Results are shown in Table 4. Table 4 Data of magnetic properties of examples and contrasts
    Br (kGs) Hcj (kOe) Hk (kOe) Hk/Hcj (%) BHmax (MGOe)
    Example 1 11.52 32.44 19.47 60.00 32.88
    Example 2 11.53 33.01 19.89 60.25 32.92
    Example 3 11.60 34.56 21.55 62.36 33.02
    Example 4 11.94 26.23 16.98 64.74 33.14
    Example 5 11.93 26.85 17.79 66.26 33.25
    Example 6 11.93 27.88 18.56 66.57 33.52
    Example 7 10.04 29.88 21.51 72 24.55
    Example 8 10.05 32.25 23.86 74 25.24
    Example 9 12.16 27.53 20.65 75 34.71
    Example 10 10.02 30.25 20.82 68.8 24.84
    Example 11 12.11 25.93 18.75 72.3 34.33
    Contrast 1 11.48 23.88 14.52 60.80 31.52
    Contrast 2 11.49 23.91 14.66 61.31 31.61
    Contrast 3 11.52 24.62 14.63 59.42 31.58
    Contrast 4 11.93 22.56 12.20 54.08 33.02
    Contrast 5 11.86 24.21 12.18 50.31 32.84
    Contrast 6 11.87 24.56 12.14 49.43 32.86
    Contrast 7 9.98 21.89 12.24 55.92 24.01
    Contrast 8 9.84 24.15 13.32 55.16 23.71
    Contrast 9 12.01 11.52 3.01 26.1 27.94
    Contrast 10 12.03 21.36 11.75 55 33.21
  • As shown in Fig. 1 to Fig. 5, in the sample of Example 4, Cu is distributed uniformly at grain boundaries, and the grain boundary Cu concentration is basically equivalent to the intragranular Cu concentration, so that the phenomenon of copper depletion at grain boundaries is avoided. With regard to product performance, compared to the samples prepared by the conventional method, the samples of the examples have basically equivalent remanence, the coercivity is increased by 5-10 kOe, Hk is increased by 1-4 kOe, and the squareness can reach 60-75%.

Claims (10)

  1. An additive, characterized by comprising the following components by mass percentage: 20-30% of organocopper complex, 0.5-1% of plasticizer, and an organic solvent, the sum of the mass percentages of the components being 100%,
    the organocopper complex being an oil-soluble substance, the mass percentage of Cu in the organocopper complex being greater than 10%, the organocopper complex containing a polar group and/or an alkyl chain having more than 3 C atoms.
  2. The additive according to claim 1, characterized in that the additive satisfies one or more of the following conditions:
    (1) the polar group in the organocopper complex is one or more of a hydroxyl group, a carboxyl group, an amino group, an ester group, and an amide group;
    (2) the organocopper complex is one or more of a substituted copper carboxylate complex, a copper carboxylate derivative, a copper thiophosphate complex, copper quinoline, copper hydroxyquinoline, copper phthalate, thiodiazole copper, copper acetylacetonate, and copper acetoacetate;
    a general formula of the substituted copper carboxylate complex is preferably [RCO2]2Cu, where, R is alkyl, alkynyl, cyclo, aryl or heteroaryl; preferably, the substituted copper carboxylate complex is one or more of fatty acid copper having 10 to 22 carbon atoms, copper styrene maleate, copper picolinate, copper 2-pyrazinecarboxylate, copper 2-ethylhexanoate, copper methacrylate, copper thiophene-2-carboxylate, copper methionine, and copper tartrate, and the fatty acid copper having 10 to 22 carbon atoms is preferably one or more of copper oleate, copper linoleate, copper stearate, copper rosinate, copper hexadecanoate, copper palmitate, and copper naphthenate;
    the copper carboxylate derivative is preferably a copper thiocarboxylate derivative [R'CS2]2Cu or a copper selenocarboxylate derivative [R'CSe2]2Cu, where, R' comprises alkyl and alkyl derivatives; and preferably, the copper carboxylate derivative is copper N,N-di-n-butyldithiocarbamate and/or copper N,N-di-n-butyldiselenocarbamate;
    the copper thiophosphate complex is preferably a copper complex of a dialkyldithiophosphate, and a general formula of the copper complex of the dialkyldithiophosphate is (RO)2P(S)SHM, where, R is alkyl or aryl, and M comprises monovalent copper and divalent copper; and preferably, the copper thiophosphate complex is one or more of copper dihexyldithiophosphate, copper dibutyldithiophosphate, copper-containing antioxidant T541, and copper-containing antioxidant T542;
    (3) the grain diameter of the organocopper complex is less than 10 µm;
    (4) the mass percentage of the organocopper complex in the additive is 20%, 22%, 23%, 25%, 27% or 30%;
    (6) the plasticizer is a phthalate and/or epoxidized soybean oil, and preferably, the plasticizer is one or more of dibutyl phthalate, dioctyl phthalate, and epoxidized soybean oil;
    (7) the mass percentage of the plasticizer in the additive is 0.5%, 0.8% or 1%;
    (8) the organic solvent is one or more of acetone, toluene, mineral oil, methyl acetate, 120# solvent oil, isooctane, isopropanol, chloroform, and methyl methacrylate, preferably, the organic solvent is one or more of 120# solvent oil, toluene, mineral oil, acetone, isooctane, and isopropanol, and more preferably, the organic solvent is 120# solvent oil, toluene, mineral oil, a mixed solvent of isooctane and isopropanol, or a mixed solvent of acetone and isopropanol;
    (9) the mass percentage of the organic solvent in the additive is 69-79.5%; and
    (10) the additive is composed of 20-30% of organocopper complex, 0.5-1% of plasticizer, and 69-79.5% of organic solvent.
  3. Application of the additive according to claim 1 or 2 in preparation of a samarium-cobalt magnet.
  4. A preparation method of a samarium-cobalt 2: 17 type magnet, characterized by comprising: mixing samarium-cobalt magnet alloy powder with the additive according to claim 1 or 2, shaping, sintering, and aging,
    the mass percentage of Cu in the organocopper complex in the samarium-cobalt magnet alloy powder being 0.1-0.2%.
  5. The preparation method of a samarium-cobalt 2: 17 type magnet according to claim 4, characterized in that the preparation method of a samarium-cobalt 2: 17 type magnet satisfies one or more of the following conditions:
    (1) raw materials of the samarium-cobalt magnet alloy powder comprise Sm, Cu, Fe, Zr, and Co;
    preferably, the mass percentage of Sm in the raw materials of the samarium-cobalt magnet alloy powder is 24-26% such as 24%, 25.5%, and 26%;
    preferably, the mass percentage of Cu in the raw materials of the samarium-cobalt magnet alloy powder is 4-6% such as 4%, 5.5%, and 6%;
    preferably, the mass percentage of Fe in the raw materials of the samarium-cobalt magnet alloy powder is 10-20% such as 10%, 17%, 19%, and 20%;
    preferably, the mass percentage of Zr in the raw materials of the samarium-cobalt magnet alloy powder is 2.0-4% such as 2.0%, 3.5%, and 4%; and
    preferably, the mass percentage of Co in the raw materials of the samarium-cobalt magnet alloy powder is 45-60% such as 46%, 48%, 51.5%, and 56%;
    (2) the samarium-cobalt magnet alloy powder is obtained by melting and crushing the raw materials of the samarium-cobalt magnet alloy powder;
    (3) the grain diameter D50 of the samarium-cobalt magnet alloy powder is 4-6 µm; and
    (4) the samarium-cobalt magnet alloy powder is mixed with the additive, and the mixture is dried, shaped, sintered, and aged.
  6. The preparation method of a samarium-cobalt 2: 17 type magnet according to claim 5, characterized in that the preparation method of a samarium-cobalt 2: 17 type magnet satisfies one or more of the following conditions:
    (1) the samarium-cobalt magnet alloy powder is composed of 24% of Sm, 4% of Cu, 17% of Fe, 3.5% of Zr, and 51.5% of Co;
    or, the samarium-cobalt magnet alloy powder is composed of 25.5% of Sm, 5.5% of Cu, 19% of Fe, 2% of Zr, and 48% of Co;
    or, the samarium-cobalt magnet alloy powder is composed of 26% of Sm, 4% of Cu, 10% of Fe, 4% of Zr, and 56% of Co;
    or, the samarium-cobalt magnet alloy powder is composed of 24% of Sm, 6% of Cu, 20% of Fe, 4% of Zr, and 46% of Co;
    (2) the smelting is performed by melt-spinning, centrifugal casting or ingot casting;
    (3) the crushing comprises coarse crushing, secondary crushing, and fine crushing, the coarse crushing is preferably Jaw crushing, the secondary crushing is preferably disc milling or crushing with an intermediate crusher, and the fine crushing is preferably jet milling or ball milling; and
    (4) the drying is placing the powder in a dryer and drying at 80°C for 5-10 h, and the drying time is preferably 5 h, 6 h, 6.5 h, 7 h, 7.5 h, 8 h or 10 h.
  7. The preparation method of a samarium-cobalt 2: 17 type magnet according to claim 4, characterized in that the preparation method of a samarium-cobalt 2: 17 type magnet satisfies one or more of the following conditions:
    (1) the mass percentage of Cu in the organocopper complex in the samarium-cobalt magnet alloy powder is 0.1%, 0.12%, 0.14%, 0.16%, 0.18% or 0.2%;
    (2) the additive is composed of 25% of copper naphthenate, 0.50% of epoxidized soybean oil, and 74.5% of 120# solvent oil, and the mass percentage of the additive in the samarium-cobalt magnet alloy powder is preferably 2.5%;
    or, the additive is composed of 30% of copper oleate, 0.50% of epoxidized soybean oil, and 69.5% of 120# solvent oil, and the mass percentage of the additive in the samarium-cobalt magnet alloy powder is preferably 3.3%;
    or, the additive is composed of 30% of copper hexadecanoate, 0.50% of dibutyl phthalate, and 69.5% of 120# solvent oil, and the mass percentage of the additive in the samarium-cobalt magnet alloy powder is preferably 3.6%;
    or, the additive is composed of 27% of copper N,N-di-n-butyldithiocarbamate, 0.50% of dibutyl phthalate, and 72.5% of toluene, and the mass percentage of the additive in the samarium-cobalt magnet alloy powder is preferably 3.3%;
    or, the additive is composed of 25% of copper dihexyldithiophosphate, 0.80% of epoxidized soybean oil, and 74.2% of toluene, and the mass percentage of the additive in the samarium-cobalt magnet alloy powder is preferably 3.4%;
    or, the additive is composed of 22% of copper dibutyldithiophosphate, 0.80% of dioctyl phthalate, and 77.2% of mineral oil, and the mass percentage of the additive in the samarium-cobalt magnet alloy powder is preferably 2.4%;
    or, the additive is composed of 23% of T541, 0.80% of dioctyl phthalate, and 76.2% of mineral oil, and the mass percentage of the additive in the samarium-cobalt magnet alloy powder is preferably 3.5%;
    or, the additive is composed of 20% of copper acetylacetonate, 1% of epoxidized soybean oil, 40% of isooctane, and 39% of isopropanol, and the mass percentage of the additive in the samarium-cobalt magnet alloy powder is preferably 3.7%;
    or, the additive is composed of 23% of copper acetoacetate, 1% of epoxidized soybean oil, 40% of acetone, and 36% of isopropanol, and the mass percentage of the additive in the samarium-cobalt magnet alloy powder is preferably 4.4%;
    or, the additive is composed of 20% of copper hexadecanoate, 1% of epoxidized soybean oil, 40% of isooctane, and 39% of isopropanol, and the mass percentage of the additive in the samarium-cobalt magnet alloy powder is preferably 8.1%;
    or, the additive is composed of 23% of copper oleate, 1% of epoxidized soybean oil, 40% of acetone, and 36% of isopropanol, and the mass percentage of the additive in the samarium-cobalt magnet alloy powder is preferably 8.7%.
  8. The preparation method of a samarium-cobalt 2: 17 type magnet according to claim 4, characterized in that the preparation method of a samarium-cobalt 2: 17 type magnet satisfies one or more of the following conditions:
    (1) the magnetic field strength B for shaping is 1.5-2 T;
    (2) the sintering is performed in an inert atmosphere;
    (3) the sintering temperature is 1200-1220°C such as 1200°C, 1210°C, 1215°C, and 1220°C;
    (4) the sintering time is 1-5 h such as 1 h, 3 h, 4 h, and 5 h;
    (5) solution treatment is performed after sintering,
    preferably, the solution treatment temperature is 1140-1190°C such as 1140°C, 1150°C, 1160°C, and 1190°C;
    preferably, the solution treatment time is 5-40 h such as 5 h, 20 h, 35 h, and 40 h, and
    (6) the aging is keeping at 800-900°C for 5-20 h, cooling to 400°C, and keeping for 5-10 h,
    preferably, the cooling is performed at a rate of 0.7°C/min.
  9. A samarium-cobalt 2: 17 type magnet, characterized by being prepared by the preparation method of a samarium-cobalt 2: 17 type magnet according to any one of claims 4 to 8.
  10. A samarium-cobalt 2: 17 type magnet, characterized in that the grain boundary Cu concentration in the samarium-cobalt 2: 17 type magnet is basically equivalent to the intragranular Cu concentration, and
    preferably, the grain boundary Cu concentration in the samarium-cobalt 2: 17 type magnet is 3-5.6%, the intragranular Cu concentration in the samarium-cobalt 2: 17 type magnet is 3.2-6%, and the percentage is the percentage of atoms.
EP22206155.8A 2021-11-30 2022-11-08 Application of an additive in a preparation method of a samarium-cobalt 2:17 type magnet Active EP4187558B1 (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202111444382.3A CN114255945A (en) 2021-11-30 2021-11-30 Additive and application thereof, 2-17 type samarium-cobalt magnet and preparation method thereof

Publications (2)

Publication Number Publication Date
EP4187558A1 true EP4187558A1 (en) 2023-05-31
EP4187558B1 EP4187558B1 (en) 2024-07-24

Family

ID=80793634

Family Applications (1)

Application Number Title Priority Date Filing Date
EP22206155.8A Active EP4187558B1 (en) 2021-11-30 2022-11-08 Application of an additive in a preparation method of a samarium-cobalt 2:17 type magnet

Country Status (2)

Country Link
EP (1) EP4187558B1 (en)
CN (1) CN114255945A (en)

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN111145973A (en) 2018-11-06 2020-05-12 中国科学院宁波材料技术与工程研究所 Samarium-cobalt permanent magnet containing grain boundary phase and preparation method thereof
CN111370191A (en) * 2020-03-20 2020-07-03 杭州永磁集团有限公司 Heavy rare earth element-free samarium-cobalt permanent magnet material with low coercive force temperature coefficient and high temperature and preparation method thereof
US20200243233A1 (en) * 2019-01-28 2020-07-30 Baotou Tianhe Magnetics Technology Co., Ltd. Samarium-Cobalt Magnets And Method For Preparing The Same
US20200243232A1 (en) * 2015-10-08 2020-07-30 Kyushu Institute Of Technology Rare earth-cobalt permanent magnet
US20210079248A1 (en) * 2014-06-19 2021-03-18 National Research Council Of Canada Molecular inks
CN113593882A (en) * 2021-07-21 2021-11-02 福建省长汀卓尔科技股份有限公司 2-17 type samarium-cobalt permanent magnet material and preparation method and application thereof

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20210079248A1 (en) * 2014-06-19 2021-03-18 National Research Council Of Canada Molecular inks
US20200243232A1 (en) * 2015-10-08 2020-07-30 Kyushu Institute Of Technology Rare earth-cobalt permanent magnet
CN111145973A (en) 2018-11-06 2020-05-12 中国科学院宁波材料技术与工程研究所 Samarium-cobalt permanent magnet containing grain boundary phase and preparation method thereof
US20200243233A1 (en) * 2019-01-28 2020-07-30 Baotou Tianhe Magnetics Technology Co., Ltd. Samarium-Cobalt Magnets And Method For Preparing The Same
CN111370191A (en) * 2020-03-20 2020-07-03 杭州永磁集团有限公司 Heavy rare earth element-free samarium-cobalt permanent magnet material with low coercive force temperature coefficient and high temperature and preparation method thereof
CN113593882A (en) * 2021-07-21 2021-11-02 福建省长汀卓尔科技股份有限公司 2-17 type samarium-cobalt permanent magnet material and preparation method and application thereof

Also Published As

Publication number Publication date
EP4187558B1 (en) 2024-07-24
CN114255945A (en) 2022-03-29

Similar Documents

Publication Publication Date Title
TWI755151B (en) R-t-b series permanent magnetic material and preparation method and application thereof
TWI704238B (en) Low b content r-fe-b based sintered magnet and preparation method thereof
EP3075874B1 (en) Low-b rare earth magnet
US20240062954A1 (en) COATING MATERIALS FOR DIFFUSING INTO MAGNET OF NdFeB AND A METHOD OF MAKING IT
EP3196896A1 (en) Heavy rare earth free sintered nd-fe-b magnets and manufacturing process thereof
EP3968344A1 (en) Neodymium iron boron magnet having gradient distribution and preparation method therefor
CN111145973B (en) Samarium-cobalt permanent magnet containing grain boundary phase and preparation method thereof
CN101982855A (en) Sintered Nd-Fe-B permanent-magnet material and preparation method thereof
EP2830069A1 (en) R-T-B-M sintered magnet and manufacturing method thereof
US20240242862A1 (en) Neodymium-iron-boron magnet prepared by using waste sintered magnet and method for preparing neodymium-iron-boron magnet by using waste materials
US9901984B2 (en) Method for preparing R-Fe-B based sintered magnet
EP3667685A1 (en) Heat-resistant neodymium iron boron magnet and preparation method therefor
JP2022094920A (en) Preparation method for sintered magnetic body
CN109859922A (en) A kind of preparation method of the R-Fe-B magnet of low heavy rare earth content
KR20140133552A (en) Neodymium-based rare-earth permanent magnet and process for producing same
CN111210960B (en) High-squareness-degree high-magnetic-energy-product samarium cobalt permanent magnet material and preparation method thereof
EP4187558A1 (en) Additive and application thereof, and samarium-cobalt 2: 17 type magnet and preparation method thereof
CN108878090B (en) Heavy rare earth-free neodymium iron boron sintered magnet and preparation method thereof
CN111383808B (en) Preparation method of high-remanence high-coercivity neodymium iron boron magnet
CN110942877A (en) Neodymium-iron-boron magnet and preparation method thereof
CN105355352B (en) A kind of samarium-cobalt magnet of low-coercivity and preparation method thereof
EP4254438A1 (en) Neodymium magnet and method for manufacturing neodymium magnet by three-dimensional grain boundary diffusion
WO2014059771A1 (en) Oxygen containing re-(fe, tm)-b based sintered magnet and preparing method thereof
Ragg et al. A study of the effects of heat treatment on the microstructures and magnetic properties of Cu-added Nd Fe B type sintered magnets
EP4354471A1 (en) Auxiliary alloy casting piece, high-remanence and high-coercive force ndfeb permanent magnet, and preparation methods thereof

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: THE APPLICATION HAS BEEN PUBLISHED

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC ME MK MT NL NO PL PT RO RS SE SI SK SM TR

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: REQUEST FOR EXAMINATION WAS MADE

17P Request for examination filed

Effective date: 20230818

RBV Designated contracting states (corrected)

Designated state(s): AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC ME MK MT NL NO PL PT RO RS SE SI SK SM TR

RIC1 Information provided on ipc code assigned before grant

Ipc: B22F 1/10 20220101ALI20240118BHEP

Ipc: H01F 41/02 20060101ALI20240118BHEP

Ipc: H01F 7/02 20060101ALI20240118BHEP

Ipc: H01F 1/055 20060101ALI20240118BHEP

Ipc: H01F 1/01 20060101AFI20240118BHEP

GRAP Despatch of communication of intention to grant a patent

Free format text: ORIGINAL CODE: EPIDOSNIGR1

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: GRANT OF PATENT IS INTENDED

INTG Intention to grant announced

Effective date: 20240227

RIN1 Information on inventor provided before grant (corrected)

Inventor name: SHI, DAWEI

Inventor name: WANG, GUOXIONG

Inventor name: WU, MAOLIN

Inventor name: ZHANG, CHANG

Inventor name: OUYANG, FUZHONG

Inventor name: FU, ZHONGWEI

GRAS Grant fee paid

Free format text: ORIGINAL CODE: EPIDOSNIGR3

AK Designated contracting states

Kind code of ref document: B1

Designated state(s): AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC ME MK MT NL NO PL PT RO RS SE SI SK SM TR

REG Reference to a national code

Ref country code: GB

Ref legal event code: FG4D

REG Reference to a national code

Ref country code: CH

Ref legal event code: EP

REG Reference to a national code

Ref country code: DE

Ref legal event code: R096

Ref document number: 602022004805

Country of ref document: DE