WO2014101855A1 - 基于细粉热处理的稀土磁铁制造方法 - Google Patents

基于细粉热处理的稀土磁铁制造方法 Download PDF

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WO2014101855A1
WO2014101855A1 PCT/CN2013/090825 CN2013090825W WO2014101855A1 WO 2014101855 A1 WO2014101855 A1 WO 2014101855A1 CN 2013090825 W CN2013090825 W CN 2013090825W WO 2014101855 A1 WO2014101855 A1 WO 2014101855A1
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heat treatment
fine powder
rare earth
earth magnet
temperature
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PCT/CN2013/090825
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English (en)
French (fr)
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永田浩
吴冲浒
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厦门钨业股份有限公司
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Priority to US14/758,698 priority Critical patent/US10242778B2/en
Publication of WO2014101855A1 publication Critical patent/WO2014101855A1/zh

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    • 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
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    • B22F3/00—Manufacture of workpieces or articles from metallic powder characterised by the manner of compacting or sintering; Apparatus specially adapted therefor ; Presses and furnaces
    • B22F3/12—Both compacting and sintering
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    • B22F9/00—Making metallic powder or suspensions thereof
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    • 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
    • C21D1/74—Methods of treatment in inert gas, controlled atmosphere, vacuum or pulverulent material
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    • C22C38/002—Ferrous alloys, e.g. steel alloys containing In, Mg, or other elements not provided for in one single group C22C38/001 - C22C38/60
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    • C22C38/54—Ferrous alloys, e.g. steel alloys containing chromium with nickel with boron
    • H—ELECTRICITY
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    • 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
    • H01F1/0536—Alloys characterised by their composition containing rare earth metals sintered
    • 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
    • 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
    • H01F41/0266—Moulding; Pressing
    • H—ELECTRICITY
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    • 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
    • B—PERFORMING OPERATIONS; TRANSPORTING
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    • B22F9/00—Making metallic powder or suspensions thereof
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    • B22F2009/044—Making metallic powder or suspensions thereof using physical processes starting from solid material, e.g. by crushing, grinding or milling by jet milling
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Definitions

  • the invention relates to the technical field of manufacturing magnets, in particular to a method for manufacturing a rare earth magnet based on heat treatment of fine powder.
  • the rare earth magnet is a magnet based on the intermetallic compound R 2 T 14 B, wherein R is a rare earth element, T is iron, or a transition metal element replacing a part of iron and iron, and B is boron, which is extremely high.
  • the magnetic properties known as magnetic king, its maximum magnetic energy product (BH)max is more than 10 times the maximum magnetic energy product of ferrite magnets.
  • the working temperature of rare earth magnets can reach up to 200 degrees Celsius, and the machining performance is extremely high. Good, and its hard texture, stable performance, good cost performance, and extremely wide application.
  • the manufacturing process of the sintered rare earth magnet mainly includes the following processes: raw material preparation ⁇ melting ⁇ casting ⁇ hydrogen breaking pulverization (HD) ⁇ airflow pulverization (JM) ⁇ magnetic field forming ⁇ sintering ⁇ heat treatment ⁇ magnetic property evaluation ⁇ sintered body Evaluation of oxygen content ⁇ processing ⁇ surface treatment, etc.
  • the grain boundary diffusion method is a method of diffusing heavy rare earths such as Dy and Tb in the grain boundary of the sintered magnet by the following methods 1) to 3):
  • Heavy-rich rare earth alloy powder coating method coating powder of DyH 2 powder, TbH 2 powder, (Dy or Tb )-Co-Ni-Al metal compound powder, and then magnetizing the magnet at a temperature of 700 ° C to 900 ° C Grain boundary diffusion of elements such as Dy and Tb;
  • evaporation method using high-temperature evaporation source to generate heavy rare earth metal vapors such as Dy and Tb, at 700 ° C ⁇ 900 ° C At the temperature of the rare earth magnet, grain boundary diffusion of elements such as Dy and Tb is performed.
  • the Br and (BH)max of the magnet remain basically unchanged, but the coercive force can be increased by 7kOe.
  • the heat resistance of the magnet can be increased by about 40 °C.
  • the magnet will react with the placing table and the tooling, resulting in poor scratches on the surface of the magnet material, and the cost of the tool is also high;
  • the oxygen content of the magnet is relatively low, the oxidation inside and outside the magnet is not uniform, and there is no uniform dispersed oxide layer, RH After the diffusion, the magnet is easily deformed (bent).
  • the object of the present invention is to overcome the deficiencies of the prior art and provide a method for manufacturing a rare earth magnet based on heat treatment of fine powder. Since the oxide layer is uniformly formed on the surface of the entire powder, the existence state of oxygen at the grain boundary of the magnet is changed significantly, the diffusion rate of the heavy rare earth element is increased, the diffusion efficiency is improved, and the crystal can be completed in a shorter time. Boundary diffusion .
  • the rare earth magnet is a magnet containing a R 2 T 14 B main phase, and the R is at least one selected from the group consisting of rare earth elements including a lanthanum element.
  • T is at least one transition metal element including Fe, and includes the steps of: coarsely pulverizing the rare earth magnet with an alloy and then finely pulverizing it by a jet mill to form a fine powder in a vacuum or an inert gas atmosphere.
  • the heat treatment is performed at a temperature of 100 ° C to 1000 ° C for 6 minutes or more and 24 hours or less, and then formed by a magnetic field forming method, and sintered at a temperature of 950 ° C to 1140 ° C in a vacuum or an inert gas to obtain a rare earth magnet sintered body; as well as
  • the rare earth magnet sintered body is processed to obtain a magnet, and then the magnet is subjected to a temperature of 700 ° C to 1020 ° C. RH grain boundary diffusion treatment process.
  • the combination of the above various factors causes the performance of the powder to change drastically. Since the oxide layer is uniformly formed on the surface of all the powders, The existence state of oxygen at the grain boundary of the magnet changes significantly, the diffusion rate of the heavy rare earth element becomes faster, the diffusion efficiency is improved, and the grain boundary diffusion can be completed in a shorter time.
  • the temperature at which the RH grain boundary diffusion treatment is performed is 1000 ° C to 1020 ° C. . Diffusion at this diffusion temperature further accelerates diffusion efficiency and shortens diffusion time.
  • the temperature of the fine powder heat treatment step is preferably from 300 ° C to 700 ° C.
  • the fine powder in the fine powder heat treatment step, is vibrated or shaken.
  • a furnace such as a rotary furnace for treatment, thereby improving production efficiency.
  • the vacuum state heat treatment step has a pressure of 10 -2 Pa to 500 Pa, an oxygen content of 0.5 ppm to 2000 ppm, and a dew point of -60 ° C to 20 ° C.
  • the invention has undergone a large number of tests to control the content of oxidizing gases (including water and oxygen) in the atmosphere so that the surface of all the alloy powders can be produced and only a very small amount of oxide layer can be produced, so that the oxygen at the grain boundary of the magnet is obtained. There is a significant change in the state of existence, accelerating the diffusion rate of heavy rare earth elements.
  • the mean free path of the oxidizing gas is inversely proportional to the pressure P, and therefore, the probability of the reaction of the oxidizing gas with the single alloy powder More uniform, the powders located in the surface layer, the middle layer and the bottom layer are oxidized to obtain a high performance powder.
  • the inert gas atmosphere heat treatment step has a pressure of 10 -1 Pa to 1000 Pa, an oxygen content of 0.5 ppm to 2000 ppm, and a dew point of -60 ° C to 20 ° C.
  • the effect is the same as the previous paragraph.
  • the alloy for a rare earth magnet is obtained by cooling a raw material alloy melt by a strip casting method at a cooling rate of 10 2 ° C /sec or more and 10 4 ° C /sec or less.
  • the step of coarsely pulverizing is to use an alloy of rare earth magnets at 0.01 MPa or more and 1 MPa.
  • the following hydrogen pressure is maintained for 0.5 to 6 hours to carry out hydrogen pulverization, followed by vacuum dehydrogenation.
  • the rare earth magnet alloy is in atomic percent and has a composition of R e T f A g J h G i D k , wherein:
  • R is Nd or contains Nd and is selected from La, Ce, Pr, Sm, Gd, Dy, At least one of Tb , Ho , Er , Eu , Tm , Lu or Y
  • T is Fe or contains Fe and at least one selected from the group consisting of Ru, Co or Ni
  • A is B or contains B and at least one selected from C or P
  • J is at least one selected from the group consisting of Cu, Mn, Si or Cr
  • G is selected from Al, Ga
  • D being at least one selected from the group consisting of Zr, Hf, V, Mo, W, Ti or Nb;
  • the atomic percentage of e is at 12 ⁇ e ⁇ 16,
  • the atomic percentage of g at% is 5 ⁇ g ⁇ 9,
  • the atomic percentage of h is at 0.05 ⁇ h ⁇ 1,
  • the atomic percentage of i is at 0.2 ⁇ i ⁇ 2.0.
  • the atomic percentage of k at% is 0 ⁇ j ⁇ 4
  • the present invention has the following characteristics:
  • the performance of the powder is drastically changed by heat treatment of fine powder.
  • the magnet is cut into a desired size and subjected to grain boundary diffusion treatment.
  • the grain boundary diffusion test is performed at a temperature of 680 ° C to 1050 ° C to determine 700 ° C to 1020 ° C.
  • the grain boundary diffusion temperature and the interval of 1000 °C to 1020 °C is the most suitable Dy grain boundary diffusion treatment temperature, In this way, it is possible to select a higher diffusion temperature than the prior art when the construction period is tight, thereby eliminating the disadvantages of the excessive processing time of the existing grain boundary diffusion method;
  • the powder can be sintered at a high temperature of 20 to 40 ° C higher than the conventional method, and no abnormal grain growth occurs ( AGG), the heat-treated powder can be sintered in a particularly wide range of sintering temperatures, which broadens the production conditions.
  • Raw material preparation process preparation of 99.5% purity Nd, Pr, Dy, Tb and Gd, industrial Fe-B, industrial pure Fe, purity 99.99% Co, purity 99.5% Cu, Mn, Al, Ag, Mo and C. It is prepared in terms of atomic percentage at% according to the composition of ReTfAgJhGiDk.
  • Hydrogen pulverization (ie coarse pulverization): a cast piece with an average thickness of 0.3 mm is placed in an inner diameter of ⁇ 1200 mm In a stainless steel rotary hydrogen furnace container, the container is evacuated to a vacuum of 10 Pa or less, and then a hydrogen gas having a purity of 99.999% is introduced to a pressure of 0.12 MPa, and the container is at 1 rpm. The rotation speed was rotated for 2 hours to absorb hydrogen, and then, under a temperature of 600 ° C, vacuum dehydrogenation was carried out for 2 hours, and then the container was cooled while rotating at a rotation speed of 30 rpm, and the cooled coarse powder was taken out.
  • Fine pulverization process The coarse powder was finely pulverized by a jet mill to obtain a fine powder having an average particle diameter of 4.2 ⁇ m.
  • Fine powder heat treatment process the fine powder is divided into equal parts of 8 parts, each of which is placed in a ⁇ 1200mm stainless steel container, and the vacuum is applied to the container to a pressure of 10 -1 Pa, an oxygen content of 1 to 100 ppm, and a dew point. It is 0 to 10 ° C, and then the stainless steel container is placed in an external heat furnace for heating.
  • the heating temperature and time of each fine powder are as shown in Table 2.
  • the stainless steel container was rotated at a rotation speed of 10 rpm.
  • the container After heating, the container was taken out from the external heat furnace, and while being externally cooled by water, it was rotated at a rotation speed of 20 rpm, and cooled. Hours.
  • Forming process in a magnetic field no organic materials such as forming aids and lubricants are added to the fine powder powder after heat treatment, and a right-angle oriented magnetic field forming machine is used, in a 2.1T orientation magnetic field, under a molding pressure of 0.2 ton/cm 2 It is formed into a cube with a side length of 40 mm at one time, and is demagnetized in a magnetic field of 0.2 T after one molding.
  • secondary forming was performed under a pressure of 1.2 ton/cm 2 using a secondary molding machine (isostatic pressing machine).
  • each formed body is moved to a sintering furnace for sintering, and the sintering is maintained at a temperature of 200 ° C and 600 ° C for 2 hours under a vacuum of 10 -3 Pa, and then at 1080 ° C in an Ar gas atmosphere of 0.01 MPa.
  • the temperature was sintered for 2 hours, and then Ar gas was introduced to bring the gas pressure to 0.1 MPa, and then cooled to room temperature.
  • Heat treatment process The sintered body is subjected to high temperature Ar gas at 600 °C. 1 After the hourly heat treatment, it was taken out after cooling to room temperature.
  • Magnetic performance evaluation process sintered magnets use NIM-10000H type BH from China Metrology Institute Large-scale rare earth permanent magnet non-destructive measurement system for magnetic performance testing.
  • Oxygen content evaluation process in sintered body The oxygen content in the sintered body is EMGA-620W from Japan HORIBA Co., Ltd. The type of oxygen and nitrogen analyzer is tested.
  • the fine powder activity of forming a uniform oxide film on the surface becomes weak, and in the process of forming to sintering, even if it is exposed to the atmosphere, intense oxidation does not occur, and fine powder which is not subjected to heat treatment is active. It is more likely to be oxidized. In the process of forming to sintering, even if it is only exposed to a little atmosphere, intense oxidation occurs, and the oxygen content of the sintered body becomes high.
  • the heat treatment temperature of the fine powder exceeds 1000 °C.
  • the oxide film formed on the surface of the fine powder particles is easily diffused into the particles, the adhesion between the powders becomes higher as in the case of the non-oxidized film, so that Br, (BH) max It becomes extremely poor, and it is easy to cause abnormal grain growth (AGG) at the time of sintering, and the coercive force Hcj is lowered.
  • Raw material preparation process preparation of 99.9% purity Nd, Y, industrial Fe-B, industrial Fe-P, industrial Fe-Cr, industrial pure Fe, purity 99.9% Ni, Si, purity 99.5% Sn, W.
  • Casting process Ar gas is introduced into the melting furnace after vacuum melting to achieve a pressure of 50,000 Pa Thereafter, a cast piece having an average thickness of 2 mm was cast in a water-cooled disk-shaped cast sheet.
  • Hydrogen breaking pulverization process the cast piece is placed in a stainless steel rotary hydrogen furnace container with an inner diameter of ⁇ 1200 mm, and the container is evacuated to achieve A vacuum of 10 Pa or less is followed by a hydrogen gas having a purity of 99.999% to a pressure of 0.12 MPa, and a stainless steel rotary hydrogen furnace container is rotated at a rotation speed of 1 rpm. After hydrogen absorption and crushing in an hour, vacuum dehydrogenation was carried out at a temperature of 600 ° C for 2 hours, and then the container was cooled while rotating at a rotation speed of 30 rpm, and the cooled coarse powder was taken out.
  • Fine pulverization process The coarse powder was finely pulverized using a gas flow fine pulverizer to obtain a fine powder having an average particle diameter of 6.8 ⁇ m, which was divided into 6 equal portions.
  • Fine powder heat treatment process 4 parts of the fine powder after air flow pulverization are placed in a ⁇ 1200mm stainless steel rotary hydrogen furnace container, and the container is vacuumed to a vacuum of 10 -2 Pa and an oxygen content of 0.5 to 50 ppm.
  • the dew point is 10 to 20 ° C, and then the vessel is placed in an external heat furnace for heating; the heating temperature is 600 ° C for 2 hours, and the vessel is rotated at a rotation speed of 1 rpm when heated.
  • the container After heating, the container was taken out from the external heat furnace, and while being externally cooled by water, it was rotated at a rotation speed of 20 rpm, and cooled. Hours.
  • Forming process in a magnetic field 4 parts of the powder after heat treatment of the fine powder and 2 parts of the powder which are not subjected to the heat treatment of the fine powder are not added with organic additives, and each uses a right angle oriented type magnetic field forming machine, in a 2T orientation magnetic field, At a molding pressure of 0.20 ton/cm 2 , a cube having a side length of 40 mm is formed at one time; after one molding, the magnetic field is demagnetized in a magnetic field of 0.2 T; in order to seal the molded body after one molding as far as possible without contacting the air, Secondary forming was performed using a secondary molding machine (isostatic press molding machine) under a pressure of 1.2 ton / cm 2 .
  • a secondary molding machine isostatic press molding machine
  • Sintering process Each formed body is moved to a sintering furnace for sintering, and the sintering is maintained at a temperature of 300 ° C and 500 ° C for 2 hours under a vacuum of 10 -3 Pa, and then sintered at a temperature of 1050 ° C for 6 hours. After the Ar gas was introduced to bring the gas pressure to 0.1 MPa, it was cooled to room temperature.
  • Heat treatment The sintered body was heat-treated at 550 °C for 1 hour in high-purity Ar gas, and then cooled to room temperature and taken out.
  • Two sintered bodies made of unheated powder are processed into magnets of ⁇ 15mm and thickness of 5mm, 5mm
  • the direction is the orientation direction of the magnetic field
  • one of the magnets made of the sintered body is directly subjected to magnetic property detection as a magnet without grain boundary diffusion treatment, and the magnetic properties thereof are evaluated (Comparative Example 1), and the other
  • the magnet made of the sintered body was washed, and after the surface was cleaned, grain boundary diffusion treatment was carried out in accordance with the method in A in Table 4 (Comparative Example 2).
  • the sintered body made of 4 heat-treated powders is processed into a magnet of ⁇ 15mm and a thickness of 5mm, 5mm
  • the direction was the orientation direction of the magnetic field, and one of the magnets made of the sintered body was directly subjected to magnetic property detection as a magnet having no grain boundary diffusion treatment, and the magnetic properties thereof were evaluated (Comparative Example 3).
  • Grain boundary diffusion process will be another 3
  • the magnets processed by the sintered body made of the heat-treated powder are washed, and after the surface is cleaned, the magnets made of each sintered body are subjected to grain boundary diffusion treatment according to the methods of A, B, and C in Table 4, respectively.
  • Table 4 Grain boundary diffusion treatment method Species of grain boundary diffusion Process details A Dy oxide powder, Tb fluoride powder coating diffusion method A 3:1 ratio of Dy oxide and Tb fluoride is sprayed onto the magnet and the coated magnet is dried in high purity Ar Heat treatment at a temperature of 850 °C for 12 hours in a gas atmosphere.
  • C Dy metal vapor diffusion method In a vacuum heat treatment furnace, a Dy metal plate, a Mo mesh, and a magnet are placed together, and steam is treated in an Ar atmosphere at a temperature of 1010 ° C. 6 Hours.
  • Magnetic performance evaluation process sintered magnets use NIM-10000H type BH from China Metrology Institute Large-scale rare earth permanent magnet non-destructive measurement system for magnetic performance testing.
  • Oxygen content evaluation process in sintered body The oxygen content in the sintered body is EMGA-620W from Japan HORIBA Co., Ltd. The type of oxygen and nitrogen analyzer is tested.
  • Table 5 shows the evaluation of the magnetic properties and the evaluation of the oxygen content of the examples and comparative examples in the case of the fine powder heat treatment and the grain boundary diffusion treatment.
  • Raw material preparation process preparation of 99.5% purity La, Ce, Nd, Tb, Ho, industrial Fe-B, industrial pure Fe, purity 99.99% Ru, purity 99.5% P, Si, Cr, Ga, Sn, Zr; formulated in atomic percentage at% according to the composition of R e T f A g J h G i D k .
  • La is 0.1, Ce is 0.1, Nd is 12, Tb is 0.2, and Ho is 0.2;
  • Fe is the balance and Ru is 1;
  • P is 0.05 and B is 7;
  • Si is 0.2 and Cr is 0.2;
  • Ga is 0.2 and Sn is 0.1;
  • Zr is 0.5.
  • Hydrogen breaking pulverization process the cast piece is placed in a stainless steel rotary hydrogen furnace container with an inner diameter of ⁇ 1200 mm, and the container is evacuated to achieve A vacuum of 10 Pa or less is followed by a hydrogen gas having a purity of 99.999% to a pressure of 500 Pa, and the container is rotated at a rotation speed of 1 rpm for 2 hours to absorb hydrogen and then, at 600 ° C. At a temperature of 2 hours, vacuum dehydrogenation was carried out, and then the container was cooled while rotating at a rotation speed of 30 rpm, and the cooled coarse powder was taken out.
  • Micro-grinding process finely pulverizing the coarse powder using a gas flow fine pulverizer to obtain a fine powder having an average particle diameter of 5 ⁇ m;
  • Fine powder heat treatment process the fine powder after airflow pulverization is divided into 6 equal parts, each of which is placed in ⁇ 1200mm
  • the container is evacuated to a vacuum of 10 Pa or less, and then an Ar gas having a purity of 99.9999% is introduced to a pressure of 500 Pa.
  • the oxygen content is 1800 to 2000 ppm
  • the dew point is -60 °C to -50 °C
  • the vessel is placed in an external heat furnace for heating, and the vessel is rotated at a rotation speed of 5 rpm when heated.
  • the heating temperature and time per part are shown in Table 6.
  • the container After heating, the container was taken out from the external heat furnace, and while being externally cooled by water, it was rotated at a rotation speed of 20 rpm, and cooled. Hours.
  • Forming process in a magnetic field no organic additive is added to the powder after heat treatment of the fine powder, and a magnetic field forming machine of a right angle orientation type is directly used, and in a 1.8T orientation magnetic field, under a molding pressure of 1.2 ton/cm 2 , one time is formed.
  • a plurality of cubes having a side length of 40 mm are demagnetized in a magnetic field of 0.2 T after one molding, and the molded body after the primary molding is sealed as far as possible without coming into contact with air, and is transported to a sintering furnace.
  • each formed body is moved to a sintering furnace for sintering, and the sintering is maintained at a temperature of 200 ° C and 600 ° C for 2 hours under a vacuum of 10 -3 Pa, and then at 1080 ° C in an Ar gas atmosphere of 0.02 MPa.
  • the temperature was sintered for 2 hours, and then Ar gas was introduced to bring the gas pressure to 0.1 MPa, and then cooled to room temperature.
  • Heat treatment process The sintered body is subjected to high temperature Ar gas at 600 °C. 1 After the hourly heat treatment, it was taken out after cooling to room temperature.
  • Magnetic performance evaluation process sintered magnets use NIM-10000H type BH from China Metrology Institute
  • the bulk rare earth permanent magnet non-destructive measurement system performs magnetic property testing and evaluates the average value.
  • Oxygen content evaluation process in sintered body The oxygen content in the sintered body is EMGA-620W from Japan HORIBA Co., Ltd. The type of oxygen and nitrogen analyzer is tested.
  • Table 6 shows the magnetic property evaluation and oxygen content evaluation of the examples and comparative examples after the heat treatment of the fine powder at the same heating temperature and at different times. Shown in .
  • the heat treatment time of the fine powder is less than 0.1 at a temperature of 700 °C.
  • the effect of the heat treatment of the fine powder is insufficient, and as in the case where there is no oxide film, the adhesion between the powders becomes high, and thus Br and (BH) max become extremely poor.
  • Br and (BH) max become extremely poor.
  • it is easy to produce AGG reduces coercivity.
  • the fine powder heat treatment time exceeds 24 At the time of the hour, the oxide film formed on the surface of the fine powder particles is absorbed and diffused into the particles, and as a result, the oxygen content is increased as in the case of the non-oxidized film, and Br, (BH) max is lowered, which is highly prone to occur (AGG ), the coercive force Hcj is lowered.
  • Raw material preparation process Preparation of 99.5% purity Lu, Er, Nd, Tm, Y, industrial Fe-B, industrial pure Fe, purity 99.99% Co, purity 99.5% C, Cu, Mn, Ga, Bi, Ti, in terms of atomic percentage at%, is prepared according to the composition of R e T f A g J h G i D k .
  • Lu is 0.2
  • Er is 0.2
  • Nd is 13.5
  • Tm is 0.1
  • Y is 0.1;
  • Fe is the balance and Co is 1;
  • C is 0.05 and B is 7;
  • composition J Cu is 0.2 and Mn is 0.2;
  • Ga is 0.2 and Bi is 0.1;
  • Hydrogen breaking pulverization process the cast piece is placed in a stainless steel rotary hydrogen furnace container with an inner diameter of ⁇ 1200 mm, and the container is evacuated to achieve A vacuum of 10 Pa or less is followed by a hydrogen gas having a purity of 99.999% to a pressure of 0.12 MPa, and the container is rotated at a rotation speed of 2 rpm for 6 hours to absorb hydrogen and then at 600 ° C. At a temperature of 3 hours, vacuum dehydrogenation was carried out, and then the container was cooled while rotating at a rotation speed of 10 rpm, and the cooled coarse powder was taken out.
  • Fine pulverization process The coarse powder was finely pulverized using a jet mill to obtain a fine powder having an average particle diameter of 2 ⁇ m.
  • the fine powder after jet milling is divided into 2 equal parts.
  • Fine powder heat treatment process 1 part of fine powder is placed in a ⁇ 1200mm stainless steel rotary hydrogen furnace container, and vacuum is drawn in the container to reach a vacuum of 1 Pa or less, and then an Ar gas having a purity of 99.9999% is introduced into the vessel to a pressure of 1000 Pa, and the controlled oxygen content is 800 to 1000 ppm, and the dew point is -50 °C ⁇ -40 °C, the container is placed in an external heat furnace for heating at a temperature of 600 ° C for 2 hours. The container was rotated at a rotation speed of 5 rpm while being heated.
  • the container After heating, the container was taken out from the furnace, and while being externally cooled by water, it was rotated at a rotation speed of 5 rpm and cooled for 5 hours.
  • Forming process in a magnetic field The powder after heat treatment of the fine powder is not added with an organic additive, and a magnetic field forming machine of a right angle orientation type is directly used, and in a 1.8T orientation magnetic field, it is formed into a side at a molding pressure of 1.2 ton/cm 2 .
  • the cube having a length of 40 mm is demagnetized in a magnetic field of 0.2 T after one molding, and the molded body after the primary molding is sealed as far as possible without coming into contact with air, and is transported to a sintering furnace.
  • each formed body is moved to a sintering furnace for sintering, and the sintering is maintained at a temperature of 200 ° C and 600 ° C for 2 hours under a vacuum of 10 -3 Pa, and then 925 in an Ar gas atmosphere of 0.02 MPa, respectively.
  • Ar gas was introduced to bring the gas pressure to 0.1 MPa, and then cooled to room temperature.
  • Heat treatment process The sintered body was heat-treated at 600 ° C for 1 hour in high-purity Ar gas, and then cooled to room temperature and taken out.
  • Magnetic performance evaluation process sintered magnets use NIM-10000H type BH from China Metrology Institute
  • the bulk rare earth permanent magnet non-destructive measurement system performs magnetic property testing and evaluates the average value.
  • Oxygen content evaluation process in sintered body The oxygen content in the sintered body is EMGA-620W from Japan HORIBA Co., Ltd. The type of oxygen and nitrogen analyzer is tested.
  • Table 7 shows the magnetic property evaluation and oxygen content evaluation of the examples and comparative examples at different sintering temperatures with or without fine powder heat treatment. Shown in .
  • the serial number 1-11 is a sintered magnet made of a fine powder which has not been heat-treated
  • the serial number 12-22 is a sintered magnet made of a heat-treated fine powder.
  • Raw material preparation process Preparation of 99.5% purity Lu, Er, Nd, Tm, Y, industrial Fe-B, industrial pure Fe, purity 99.99% Co, purity 99.5% C, Cu, Mn, Ga, Bi, Ti, in terms of atomic percentage at%, is prepared according to the composition of R e T f A g J h G i D k .
  • Lu is 0.2
  • Er is 0.2
  • Nd is 13.5
  • Tm is 0.1
  • Y is 0.1;
  • Fe is the balance and Co is 1;
  • C is 0.05 and B is 7;
  • composition J Cu is 0.2 and Mn is 0.2;
  • Ga is 0.2 and Bi is 0.1;
  • Hydrogen breaking pulverization process the cast piece is placed in a stainless steel rotary hydrogen furnace container with an inner diameter of ⁇ 1200 mm, and the container is evacuated to achieve A vacuum of 10 Pa or less is followed by a hydrogen gas having a purity of 99.999% to a pressure of 0.12 MPa, and the container is rotated at a rotation speed of 2 rpm for 6 hours to absorb hydrogen and then at 600 ° C. At a temperature of 3 hours, vacuum dehydrogenation was carried out, and then the container was cooled while rotating at a rotation speed of 10 rpm, and the cooled coarse powder was taken out.
  • Fine pulverization process The coarse powder was finely pulverized using a jet mill to obtain a fine powder having an average particle diameter of 2 ⁇ m.
  • Fine powder heat treatment process the fine powder is placed in a ⁇ 1200mm stainless steel rotary hydrogen furnace container, and the vacuum is taken in the container to reach 1Pa.
  • the following vacuum is followed by the introduction of Ar gas with a purity of 99.9999% to a pressure of 900 Pa, a controlled oxygen content of 800 to 1000 ppm, and a dew point of -50 °C. ⁇ -40 °C, the container was placed in an external heat furnace for heating at a temperature of 600 ° C for 2 hours. The container was rotated at a rotation speed of 5 rpm while being heated.
  • the container After heating, the container was taken out from the furnace, and while being externally cooled by water, it was rotated at a rotation speed of 5 rpm and cooled for 5 hours.
  • Forming process in a magnetic field The powder after heat treatment of the fine powder is not added with an organic additive, and a magnetic field forming machine of a right angle orientation type is directly used, and in a 1.8T orientation magnetic field, it is formed into a side at a molding pressure of 1.2 ton/cm 2 .
  • the cube having a length of 40 mm is demagnetized in a magnetic field of 0.2 T after one molding, and the molded body after the primary molding is sealed as far as possible without coming into contact with air, and is transported to a sintering furnace.
  • Sintering process Each formed body is transferred to a sintering furnace for sintering, and the sintering is maintained at a temperature of 200 ° C and 600 ° C for 2 hours under a vacuum of 10 -3 Pa, and then 980 in an Ar gas atmosphere of 0.02 MPa, respectively. After sintering at a temperature of °C, Ar gas was introduced to bring the gas pressure to 0.1 MPa, and then cooled to room temperature.
  • Heat treatment process The sintered body was heat-treated at 600 ° C for 1 hour in high-purity Ar gas, and then cooled to room temperature and taken out.
  • the heat-treated sintered body is processed into a magnet of ⁇ 15mm and thickness of 5mm, 5mm
  • the direction is the direction of the magnetic field orientation
  • the processed magnet is washed, and after the surface is cleaned, Dy oxide and Tb fluoride are used to press 3:1.
  • the proportioned raw materials are sprayed on the magnets in a comprehensive manner, and the coated magnets are dried and heat-treated at a temperature of 680 to 1050 ° C for 12 hours in a high-purity Ar gas atmosphere.
  • Magnetic performance evaluation process sintered magnets use NIM-10000H type BH from China Metrology Institute
  • the bulk rare earth permanent magnet non-destructive measurement system performs magnetic property testing and evaluates the average value.
  • Oxygen content evaluation process in sintered body The oxygen content in the sintered body is EMGA-620W from Japan HORIBA Co., Ltd. The type of oxygen and nitrogen analyzer is tested.
  • the fine powder is heat-treated to drastically change the properties of the powder.
  • the magnet is processed into a desired size and subjected to grain boundary diffusion treatment.
  • grain boundary diffusion treatment at 680 ° C to 1050 ° C
  • the grain boundary diffusion test was carried out at a temperature of 700 ° C to 1020 ° C as the grain boundary diffusion temperature, and the optimum range of D 1 from 1000 ° C to 1020 ° C was obtained. Grain boundary diffusion treatment temperature.
  • the present invention is based on a method for producing a rare earth magnet for heat treatment of fine powder, which is characterized in that after the fine pulverization step, a heat treatment step of the fine powder is added before the forming step in the magnetic field, and the crystal grain boundary is obtained by uniformly forming an oxide layer on the surface of all the powders.
  • the existence state of oxygen changes significantly, the diffusion rate of heavy rare earth elements becomes faster, the efficiency is improved, and grain boundary diffusion can be completed in a shorter time.
  • the method can be industrially practical and has industrial applicability.

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Abstract

一种基于细粉热处理的稀土磁铁制造方法，将稀土磁铁用合金粗粉碎后通过气流磨微粉碎制成细粉，细粉在真空或惰性气氛中以100°C〜1000°C的温度进行6分钟以上24小时以下的热处理，之后使用磁场成形法进行成形，在真空或惰性气体中以900°C〜1140°C的温度进行烧结，获得稀土磁铁烧结体，对烧结体进行加工获得磁铁，之后在700°C〜1020°C的温度下进行RH晶界扩散处理。

Description

基于细粉热处理的稀土磁铁制造方法 技术领域
本发明涉及磁铁的制造技术领域，特别是涉及一种基于细粉热处理的稀土磁铁制造方法。
背景技术
稀土磁铁是以金属间化合物 R2T14B 为基础的磁铁，这其中，R是稀土元素，T是铁，或者是取代铁和铁的一部分的过渡金属元素，B是硼，其拥有极高的磁性能，被人们称为磁王，其最大磁能积（BH）max是铁氧体磁铁（Ferrite）最大磁能积10倍以上，另外，稀土磁铁的工作温度最高可达200摄氏度，机械加工性能极佳，而且其质地坚硬，性能稳定，有很好的性价比，应用极其广泛。
稀土磁铁的制作工艺有以下二种：一种是烧结稀土磁铁，另一种是粘结稀土磁铁。这其中，又以烧结稀土磁铁的应用最为广泛。现有技术中，烧结稀土磁铁的制作工艺主要包括如下流程：原料配制→熔炼→铸造→氢破粉碎（HD）→气流粉碎（JM）→磁场成形→烧结→热处理→磁性能评价→烧结体中的氧含量评价→加工→表面处理等。
用一句话来概括稀土烧结磁铁的发展史的话，可以说成是提高主相含有率，降低稀土组成的开发过程也不为过。目前，为提高(BH)max、矫顽力，制造方法整体的防氧化技术不断发展，目前烧结磁铁中的氧含量可降至2500ppm以下，但是，烧结中氧含量较低的话，细微组成波动、工序中杂质的混入等不稳定因素的影响也会扩大，这就容易引起过烧结现象和晶粒异常长大（AGG），也会产生矫顽力、方形度、耐热性低下等问题。
为提高磁铁的矫顽力、方形度，并解决耐热性低下的问题，在Nd-Fe-B烧结磁铁中进行Dy、Tb、Ho等重稀土的晶界扩散是很普遍的，晶界扩散处理通常是在加工工序之后，表面处理工序之前进行的。所谓晶界扩散法，就是在烧结后的磁铁晶界里，按以下1）至3）的方法，使Dy、Tb等重稀土进行扩散的方法：
1 ）将稀土氟化物（ DyF3 、 TbF3 ）、稀土氧化物（ Dy2O3 、 Tb2O3 ）等的粉末涂覆在烧结磁体表面，之后在 700℃~900℃ 的温度对磁体进行 Dy 、 Tb 等元素的晶界扩散；
2 ）富重稀土合金粉末涂覆法：涂覆 DyH2 粉、 TbH2 粉 、 ( Dy 或 Tb )- Co-Ni-Al 金属化合物粉的粉末，之后在 700℃ ～ 900℃ 的温度对磁铁进行 Dy 、 Tb 等元素的晶界扩散；
3 ）蒸镀法：利用高温蒸发源产生 Dy 、 Tb 等重稀土金属蒸汽，在 700℃ ～ 900℃ 的温度下对稀土磁体进行 Dy 、 Tb 等元素的晶界扩散。
通过晶界扩散法，磁铁的 Br 、 (BH)max 基本保持不变，但矫顽力可提高 7kOe 左右，磁体耐热性可以提高 40℃ 左右。
然而，这种在 700℃~900℃ 的温度条件下使重稀土进行扩散的晶界扩散方法虽然可以提高矫顽力，但是也存在着不足之处：
1 、扩散需要很长时间，比如，要使重稀土元素充分扩散到片厚为 10mm 的磁铁中心部位的话，所需的时间为 48 小时，然而，大量生产时，无法确保 48 小时长的扩散时间，为了提高生产效率，只好缩短扩散时间，这样，在重稀土元素（ Dy 、 Tb 或 Ho 等）尚未充分扩散至中心部位，磁体耐热性也还未充分提高的状态下进行磁铁生产；
2 、磁铁会和放置台以及冶具发生反应，致使磁铁材料表面产生不良划痕，冶具的消耗费用也很高昂；
3 、磁铁的氧含量比较低，磁体内外氧化不均匀，没有形成均匀分散的氧化层，经 RH 扩散后，磁铁容易发生变形（弯曲）。
发明内容
本发明的目的在于克服现有技术之不足，提供一种基于细粉热处理的稀土磁铁制造方法， 由于在全部粉末表面均匀形成了氧化层，由此制得的 磁铁晶界处氧的存在状态发生明显变化，重稀土元素的扩散速度变快，扩散效率提高， 可 在较短的时间内完成晶界扩散 。
本发明解决其技术问题所采用的技术方案是：
基于细粉热处理的稀土磁铁制造方法，所述的稀土磁铁为含有 R2T14B 主相的磁铁，所述的 R 为选自包含钇元素在内的稀土元素中的至少一种，所述 T 为包括 Fe 的至少一种过渡金属元素，其特征在于，包括如下的步骤：将稀土磁铁用合金粗粉碎后再通过气流磨微粉碎制成细粉，所述细粉在真空或惰性气体气氛中以 100 ℃ ～ 1000 ℃ 的温度进行 6 分钟以上 24 小时以下的热处理，之后使用磁场成形法进行成形，在真空或惰性气体中以 950 ℃ ～ 1140 ℃ 的温度进行烧结，获得稀土磁铁烧结体；以及
对所述稀土磁铁烧结体进行加工 ， 获得磁铁，之后对磁铁在 700 ℃ ～ 1020 ℃ 的温度下进行 RH 晶界扩散处理工序 。
增加细粉热处理工序之所以能够达到如上的效果，这是因为，通过细粉热处理，产生如下的现象：
1 ）全部合金粉末的表面 在真空或惰性气体气氛中不可避的氧化气体作用下均 产生了极少量的氧化层，粉末氧化活性变弱；
2 ）合金粉末的锐利边角熔解变圆，减少粉末之间的接触面，可使粉末间的润滑性变好， 修复粉末表面晶格缺陷，提高粉末取向度及磁铁矫顽力 ；
3 ）通过韧化效果去除粉末表面附近的划痕，可避免因缺陷等造成的烧结促进效果的损失。
上述多种因素综合作用，使粉末的性能发生剧变， 由于在全部粉末表面均匀形成了氧化层， 磁铁晶界处氧的存在状态发生明显变化，重稀土元素的扩散速度变快 ，扩散效率提高，可在较短的时间内完成晶界扩散 。
在推荐的实施方式中，进行 所述 RH 晶界扩散处理的温度为 1000 ℃ ～ 1020 ℃ 。在这一扩散温度下进行扩散，可进一步加快扩散效率，缩短扩散时间。
在推荐的实施方式中， 所述细粉热处理工序的温度优选为 300 ℃ ～ 700 ℃ 。
在推荐的实施方式中，所述细粉热处理工序中，对所述细粉进行振动或摇动。细粉热处理工序中，为防止粉末间的附着及凝结，最好是使用旋转炉之类的炉进行处理，可提高生产效率。
在推荐的实施方式中， 所述真空状态热处理工序中，压力在 10-2Pa ～ 500Pa ，氧含量为 0.5ppm ～ 2000ppm ，露点为 -60 ℃ ～ 20 ℃ 。 本发明经过大量的试验，控制气氛中氧化气体（包括水和氧气）含量，使全部合金粉末的表面均能产生且仅能产生极少量的氧化层，使以此获得的 磁铁晶界处氧的存在状态发生明显变化，加快重稀土元素的扩散速度 。另外，由于将真空的压力设在 500Pa 以下，远小于标准大气压的压力，根据 平均自由程的公式，氧化气体的平均自由程与压力 P 成反比，因此，氧化气体与单个合金粉末发生反应的概率更为均匀，使位于表层、中层和底层的粉末均得以发生氧化反应，从而获得高性能粉末。
在推荐的实施方式中，所述惰性气体气氛热处理工序中，压力在 10-1Pa ～ 1000Pa ，氧含量为 0.5ppm ～ 2000ppm ，露点为 -60 ℃ ～ 20 ℃ 。效果同上段。
在推荐的实施方式中，所述稀土磁铁用合金是将原料合金熔融液用带材铸件法，以 102 ℃ / 秒以上、 104 ℃ / 秒以下的冷却速度冷却得到的。
在推荐的实施方式中， 所述粗粉碎的步骤是将稀土磁铁用合金在 0.01MPa 以上、 1MPa 以下的氢气压力下保持 0.5 ～ 6 小时进行氢破粉碎，之后抽真空脱氢的步骤。
在推荐的实施方式中，所述稀土磁铁用合金以原子百分比计，其成分为 ReTfAgJhG iDk ，其中：
其中， R 为 Nd 或包含 Nd 和选自 La 、 Ce 、 Pr 、 Sm 、 Gd 、 Dy 、 Tb 、 Ho 、 Er 、 Eu 、 Tm 、 Lu 或 Y 中的至少一种， T 为 Fe 或包含 Fe 和选自 Ru 、 Co 或 Ni 中的至少一种， A 为 B 或包含 B 和选自 C 或 P 中的至少一种， J 为选自 Cu 、 Mn 、 Si 或 Cr 中的至少一种， G 为选自 Al 、 Ga 、 Ag 、 Bi 或 Sn 中的至少一种， D 为选自 Zr 、 Hf 、 V 、 Mo 、 W 、 Ti 或 Nb 中的至少一种；以及
e 的原子百分比 at% 为 12≤e≤16 ，
g 的原子百分比 at% 为 5≤g≤9 ，
h 的原子百分比 at% 为 0.05≤h≤1 ，
i 的原子百分比 at% 为 0.2≤i≤2.0 ，
k 的原子百分比 at% 为 0≤j≤4 ，
f 的原子百分比 at% 为 f ＝ 100-e-g-h-i-k 。
与现有技术相比，本发明具有如下的特点：
1 ）由于全部粉末表面均匀形成了氧化层， 由此制得的磁铁晶界处氧的存在状态发生明显变化，重稀土元素的扩散速度变快，扩散效率提高， 可 在较短的时间内完成晶界扩散 ；
2 ）扩散时无需附着冶具，防止磁铁材料表面产生不良划痕；
3 ）通过细粉热处理，使粉末的性能发生剧变， 烧结后将磁铁切削加工为期望的尺寸，进行晶界扩散处理，本发明中，在 680 ℃ ～ 1050 ℃ 的温度下进行了晶界扩散试验，确定 700 ℃ ～ 1020 ℃ 作为其晶界扩散温度，并以 1000 ℃ ～ 1020 ℃ 区间为最合适的 Dy 晶界扩散处理温度 ， 这样，可以在工期紧张时，选择使用较现有技术更高的扩散温度，从而消除现有晶界扩散方法处理时间过长的弊端 ；
4 ）通过实施本发明的 细粉热处理 工序，全部粉末表面均匀形成了氧化层，可进行无弯曲磁铁（或称无变形磁铁）的大量生产；
5 ）与以往相比，粉末能在比常规方法高 20 ～ 40 ℃ 的高温下进行烧结，并且不会发生晶粒异常长大（ AGG ），热处理后的粉末能在特别广泛的烧结温度范围都可进行烧结，拓宽了生产条件。
具体实施方式
以下结合实施例对本发明作进一步详细说明。
实施例1
原料配制过程：准备纯度99.5%的Nd、Pr、Dy、Tb和Gd，工业用Fe-B，工业用纯Fe，纯度99.99%的Co，纯度99.5%的Cu、Mn、Al、Ag、Mo和C。以原子百分比at%计，按照成分为ReTfAgJhGiDk来配制。
各元素的含量如下表1所示：
表1 各元素的配比
R T A J G D
Nd Pr Dy Tb Gd Fe Co C B Cu Mn Al Ag Mo
7 3 1 1 1 余量 1 0.05 7 0.2 0.2 0.2 0.1 1
按照上述配制组成，合计称量、配制了 500Kg 的原料。
熔炼过程：取 500Kg 配制好的原料放入氧化铝制的坩埚中，在高频真空感应熔炼炉中在 1Pa 的真空中以 1650 ℃ 以下的温度进行真空熔炼。
铸造过程：在真空熔炼后的熔炼炉中通入 Ar 气体使气压达到 8 万 Pa 后，使用甩带铸造法（ SC ）铸造成平均厚度为 0.3mm 的 铸片 。
氢破粉碎（即粗粉碎）过程：将平均厚度为 0.3mm 的铸片放入内径为 ϕ 1200mm 的不锈钢制旋转式氢破炉容器中，容器抽真空使达到 10Pa 以下的真空，之后通入纯度为 99.999% 的氢气至压力为 0.12MPa ，容器按 1rpm 的旋转速度旋转 2 小时吸氢破碎，之后，在 600 ℃ 的温度下抽 2 小时真空脱氢，而后按 30rpm 的旋转速度一边旋转容器一边冷却，取出冷却后的粗粉。
微粉碎过程：用气流微粉碎机对粗粉进行微粉碎，获得平均粒径为 4.2μm 的细粉。
细粉热处理过程：将细粉分成均等的 8 份，每份细粉分别放入 ϕ1200mm 的不锈钢制容器中，分别 在容器中抽真空使压力至 10-1Pa ， 氧含量为 1 ～ 100ppm ，露点为 0 ～ 10 ℃ ， 之后将不锈钢制容器放入外热式炉中进行加热。
每份细粉加热温度、时间如表 2 所示，加热时不锈钢制容器以 10rpm 的旋转速度进行旋转。
加热后，将容器从外热式炉中取出，一边在外部进行水冷一边按 20rpm 的旋转速度进行旋转，冷却 3 小时。
磁场中成形过程：热处理后的细粉粉末中不添加成形助剂及润滑剂等有机物，使用直角取向型的磁场成型机，在 2.1T 的取向磁场中，在 0.2ton/cm2 的成型压力下，一次成形为边长为 40mm 的立方体，一次成形后在 0.2T 的磁场中退磁。
为使一次成形后的成形体尽可能地不接触到空气将其进行密封，使用二次成形机（等静压成形机）在 1.2ton/cm2 的压力下进行二次成形。
烧结过程：将各成形体搬至烧结炉进行烧结，烧结在 10-3Pa 的真空下，在 200 ℃ 和 600 ℃ 的温度下各保持 2 小时后，在 0.01MPa 的 Ar 气体气氛中以 1080 ℃ 的温度烧结 2 小时，之后通入 Ar 气体使气压达到 0.1MPa 后，冷却至室温。
热处理过程：烧结体在高纯度 Ar 气中，以 600 ℃ 温度进行 1 小时热处理后，冷却至室温后取出。
磁性能评价过程：烧结磁铁使用中国计量院的 NIM-10000H 型 BH 大块稀土永磁无损测量系统进行磁性能检测。
烧结体中的氧含量评价过程：烧结体中的氧含量使用日本 HORIBA 公司的 EMGA-620W 型氧氮分析仪进行检测。
表2 不同加热温度、时间的细粉热处理后的磁性能评价和氧含量评价的情况
序号 　 热处理温度(℃) 热处理时间(hr) Br ( kGs) Hcj ( k0e) SQ(%) (BH)max(MG0e) 烧结体氧含量( ppm)
0 比较例 无细粉热处理 10.1 11.4 82 21.4 2580
1 比较例 80 30 10.2 11.6 82.3 22.8 1589
2 本发明 100 24 12 35.1 98.2 31.2 562
3 本发明 300 6 12.3 35.4 99.1 35.3 375
4 本发明 500 4 12.3 36.7 99.1 35.2 369
5 本发明 700 1 12.3 37.8 99.2 35.2 383
6 本发明 1000 0.3 11.8 34.5 98.5 33.2 582
7 比较例 1020 0.5 10.6 27.6 84.2 23.2 1587
8 比较例 1050 12 10.2 24.3 78.6 16.5 2598
从表 2 可以看出，通过细粉热处理，均匀地在全部粉末表面形成非常薄的氧化膜，可使粉末间的润滑性变好，提高粉末的取向度，这样就可获得较高的 Br 、（ BH ） max ，且烧结时不易引起晶粒异常长大，可形成较细的组织，矫顽力 Hcj 激增；另外，通过细粉热处理，粉末表面的锐利部被熔解，形状变圆，局部的反磁场系数变高，这样也可获得较高的矫顽力。且，在成形至烧结的工序，表面形成均匀氧化膜的细粉活性变弱，在成形至烧结的工序，就算接触到大气，也不会发生激烈的氧化，而没有经过热处理的细粉则活性较强容易氧化，在成形至烧结的工序，就算只接触到一点点的大气，也会发生激烈的氧化，导致烧结体的氧含量变高。
需要说明的是，在细粉的热处理温度超过 1000 ℃ 时，细粉粒子表面生成的氧化膜容易扩散到粒子内，结果就会同无氧化膜一样，粉末间的附着力变高，这样的话， Br 、（ BH ） max 会变得极差，且烧结时就容易产生晶粒异常长大（ AGG ），使矫顽力 Hcj 降低。
以往，在低氧含量工序中，由于磁铁粉末间的粘着力很强，存在磁铁粉末取向度不高的问题，这样也会存在磁铁 Br 、（ BH ） max 低下的问题，且由于磁铁粉末间表面活性度很高，烧结时晶粒和晶粒容易融合，就会产生晶粒异常长大（ AGG ），使矫顽力急降， 在使用了本发明的方法之后， 上述问题同样得以解决。
实施例2
原料配制过程：准备纯度99.9%的Nd、Y，工业用Fe-B，工业用Fe-P，工业用Fe-Cr，工业用纯Fe、纯度99.9%的Ni、Si，纯度99.5%的Sn、W。
以原子百分比 at% 计，按照成分为 ReTfAgJhG iDk 来配制。
各元素的含量如表 3 所示：
表3 各元素的配比
R T A J G D
Nd Y Fe Ni B P Cr Si Sn W
12.7 0.1 余量 0.1 5.9 0.05 0.2 0.1 0.3 0.01
按照上述配制组成，合计称量、配制了 500Kg 的原料。
熔炼过程：取 500Kg 配制好的原料放入氧化铝制的坩埚中，在高频真空感应熔炼炉中在 10-2Pa 的真空中以 1600 ℃ 以下的温度进行真空熔炼。
铸造过程：真空熔炼后的熔炼炉中通入 Ar 气体使气压达到 5 万 Pa 后，在水冷圆盘状铸造板中铸造成平均厚度为 2mm 的铸片。
氢破粉碎过程：将铸片放入内径为 ϕ 1200mm 的不锈钢制旋转式氢破炉容器中，容器抽真空使达到 10Pa 以下的真空，之后通入纯度为 99.999% 的氢气至压力 0.12MPa ，不锈钢制旋转式氢破炉容器按 1rpm 的旋转速度旋转 2 小时吸氢破碎，之后在 600 ℃ 的温度下抽 2 小时真空脱氢，而后按 30rpm 的旋转速度一边旋转容器一边冷却，取出冷却后的粗粉。
微粉碎过程：使用气流微粉碎机对粗粉进行微粉碎，获得平均粒径为6.8μm的细粉，分成6等份。
细粉热处理过程： 4 份气流粉碎后的细粉分别放入 ϕ 1200mm 的不锈钢制旋转式氢破炉容器中，将 容器分别抽真空使真空度至 10-2Pa ， 氧含量为 0.5 ～ 50ppm ，露点为 10 ～ 20 ℃ ， 之后将容器放入外热式炉中进行加热；加热温度为 600 ℃ ，时间为 2 小时，加热时容器以 1rpm 的旋转速度进行旋转。
加热后，将容器从外热式炉中取出，一边在外部进行水冷一边按 20rpm 的旋转速度进行旋转，冷却 3 小时。
磁场中成形过程： 4 份 细粉热处理后的粉末 和剩余 2 份不经过细粉热处理的粉末中均不添加有机添加剂，并各自使用直角取向型的磁场成型机，在 2T 的取向磁场中，在 0.20ton/cm2 的成型压力下，一次成形为边长 40mm 的立方体；一次成形后在 0.2T 的磁场中退磁；为使一次成形后的成形体尽可能地不接触到空气将其进行密封，使用二次成形机（等静压成形机）在 1.2ton/cm2 的压力下进行二次成形。
烧结过程：将各成形体搬至烧结炉进行烧结，烧结在 10-3Pa 的真空下，在 300 ℃ 和 500 ℃ 的温度下各保持 2 小时后，以 1050 ℃ 的温度烧结 6 小时，之后通入 Ar 气体使气压达到 0.1MPa 后，冷却至室温。
热处理过程：烧结体在高纯度 Ar 气中，以 550 ℃ 温度进行 1 小时热处理后，冷却至室温后取出。
加工过程：将 2 份未经过热处理的粉末制成的烧结体加工成 ϕ15mm 、厚度 5mm 的磁铁， 5mm 方向为磁场取向方向，其中 1 份烧结体制成的磁铁作为无晶界扩散处理的磁铁直接进行磁性能检测，评定其磁特性（比较例 1 ），另 1 份烧结体制成的磁铁洗净，表面洁净化后，按表 4 中 A 中方法进行晶界扩散处理（比较例 2 ）。
将 4 份经过热处理的粉末制成的烧结体加工成 ϕ 15mm 、厚度 5mm 的磁铁， 5mm 方向为磁场取向方向，其中 1 份烧结体制成的磁铁作为无晶界扩散处理的磁铁直接进行磁性能检测，评定其磁特性（比较例 3 ）。
晶界扩散处理过程：将另外 3 份由经过热处理的粉末制成的烧结体加工后的磁铁洗净，表面洁净化后，每份烧结体制成的磁铁分别按表 4 中 A 、 B 、 C 三种方法进行晶界扩散处理 。
表4 晶界扩散处理方法
　 晶界扩散的种类 工序明细
A Dy 氧化物粉末、 Tb 氟化物粉末的涂覆扩散法 使用 Dy 氧化物和 Tb 氟化物按 3:1 比例配制成的原料，全面喷雾涂覆在磁铁上，将涂覆后的磁铁干燥，在高纯度 Ar 气体气氛中，以 850 ℃ 的温度扩散热处理 12 小时。
B （ Dy 、 Tb)-Ni-Co-Al 系合金细粉涂覆扩散法 将 Dy30Tb30Ni5Co25Al10 合金微粉碎为平均结晶粒为 15μm 的细粉，全面喷雾涂覆在磁石上，将涂布后的磁铁干燥，在高纯度 Ar 气体气氛中，以 950 ℃ 的温度扩散热处理 12 小时。
C Dy 金属蒸汽扩散法 在真空热处理炉中，将 Dy 金属板、 Mo 网和磁铁一起放入，以 1010 ℃ 的温度在 Ar 气氛中蒸汽处理 6 小时。
磁性能评价过程：烧结磁铁使用中国计量院的 NIM-10000H 型 BH 大块稀土永磁无损测量系统进行磁性能检测。
烧结体中的氧含量评价过程：烧结体中的氧含量使用日本 HORIBA 公司的 EMGA-620W 型氧氮分析仪进行检测。
表 5 是在细粉热处理和晶界扩散处理情况下实施例和比较例的磁性能评价和氧含量评价的情况。
表5 实施例和比较例的磁性能评价和氧含量评价的情况
序号 　 细粉热处理 晶界扩散 Br(kGs) Hcj ( k0e) SQ(%) (BH)max(MG0e) 烧结体氧含量( ppm)
0 比较例 1 无 无 13.1 6.5 76.5 23.1 2687
1 比较例 2 无 A 13.2 13.2 86.6 32.5 2785
2 比较例 3 有 无 15.4 9.5 86.7 46.4 421
3 本发明 有 A 15.5 22.3 98.4 56.5 278
4 本发明 有 B 15.6 22.4 99.2 56.8 276
5 本发明 有 C 15.6 24.2 99.1 57.2 289
从表 5 可以看出， 由经过热处理的细粉烧结制得的磁铁 晶界处氧的存在状态发生明显变化， Dy 、 Tb 等的扩散速度变快，扩散效率高，可以在较短的时间内完成晶界扩散 ，晶界扩散的效果非常明显，矫顽力显著提高。
实施例3
原料配制过程：准备纯度99.5%的La、Ce、Nd、Tb、Ho，工业用Fe-B，工业用纯Fe，纯度99.99%的Ru，纯度99.5%的P、Si、Cr、Ga、Sn、Zr；以原子百分比at%计，按照成分为ReTf Ag Jh Gi Dk 来配制。
各元素的含量如下所示：
R成分中，La为0.1，Ce为0.1，Nd为12，Tb为0.2，Ho为0.2；
T成分中，Fe 为余量，Ru为1；
A成分中，P为0.05，B为7；
J成分中，Si为0.2，Cr为0.2；
G成分中，Ga为0.2，Sn为0.1；
D成分中，Zr为0.5。
按照上述配制组成，合计称量、配制了 500Kg 的原料。
熔炼过程：取 500Kg 配制好的原料放入氧化铝制的坩埚中，在高频真空感应熔炼炉中在 1Pa 的真空中以 1650 ℃ 以下的温度进行真空熔炼。
铸造过程：在真空熔炼后的熔炼炉中通入 Ar 气体使气压达到 8 万 Pa 后，使用甩带铸造法（ SC ）铸造成平均厚度为 0.15mm 的铸片。
氢破粉碎过程：将铸片放入内径为 ϕ 1200mm 的不锈钢制旋转式氢破炉容器中，容器抽真空使达到 10Pa 以下的真空 ，之后通入纯度为 99.999% 的氢气至压力为 500Pa ，容器按 1rpm 的旋转速度旋转 2 小时吸氢破碎，之后，在 600 ℃ 的温度下抽 2 小时真空脱氢，而后按 30rpm 的旋转速度一边旋转容器一边冷却，取出冷却后的粗粉。
微粉碎过程：使用气流微粉碎机对粗粉进行微粉碎，获得平均粒径为 5μm 的细粉；
细粉热处理过程：气流粉碎后的细粉分成 6 等份，每份依次放入 ϕ1200mm 的不锈钢制旋转式氢破炉容器中， 容器抽真空使达到 10Pa 以下的真空，之后通入纯度为 99.9999% 的 Ar 气至压力为 5 00 Pa ，控制 氧含量为 1800 ～ 2000ppm ，露点为 -60 ℃ ～ -50 ℃ ， 再将容器放入外热型炉中进行加热，加热时容器以 5rpm 的旋转速度进行旋转。
每份加热温度、时间如表 6 中所示。
加热后，将容器从外热式炉中取出，一边在外部进行水冷一边按 20rpm 的旋转速度进行旋转，冷却 3 小时。
在磁场中成形过程：细粉热处理后的粉末中不添加有机添加剂，直接使用直角取向型的磁场成型机，在 1.8T 的取向磁场中，在 1.2ton/cm2 的成型压力下，一次成形为多个边长 40mm 的立方体，一次成形后在 0.2T 的磁场中退磁，为使一次成形后的成形体尽可能地不接触到空气将其进行密封，运至烧结炉。
烧结过程：将各成形体搬至烧结炉进行烧结，烧结在 10-3Pa 的真空下，在 200 ℃ 和 600 ℃ 的温度下各保持 2 小时后，在 0.02MPa 的 Ar 气体气氛中以 1080 ℃ 的温度烧结 2 小时，之后通入 Ar 气体使气压达到 0.1MPa 后，冷却至室温。
热处理过程：烧结体在高纯度 Ar 气中，以 600 ℃ 温度进行 1 小时热处理后，冷却至室温后取出。
磁性能评价过程：烧结磁铁使用中国计量院的 NIM-10000H 型 BH 大块稀土永磁无损测量系统进行磁性能检测，评价平均值。
烧结体中的氧含量评价过程：烧结体中的氧含量使用日本 HORIBA 公司的 EMGA-620W 型氧氮分析仪进行检测。
相同加热温度、不同时间的细粉热处理后的实施例和比较例的磁性能评价和氧含量评价的情况如表 6 中所示。
表6 实施例和比较例的磁性能评价和氧含量评价的情况
序号 热处理温度（ ℃ ） 热处理时间（ hr ） Br(kGs) Hcj ( k0e) SQ(%) (BH)max(MG0e) 烧结体中氧含量（ ppm ）
0 比较例 700 0.05 13.8 9.8 81.2 45.3 2980
1 本发明 700 0.1 15.1 13.3 97.8 54.3 565
2 本发明 700 1 15.2 13.6 98.2 54.8 354
3 本发明 700 4 15.3 14.2 99.1 55.2 375
4 本发明 700 12 15.4 14.1 99.2 56 395
5 本发明 700 24 15.3 13.5 99.1 55.3 573
6 比较例 700 48 14.9 11.7 94.8 52.7 980
从表 6 可以看出，在 700 ℃ 的温度下，细粉的热处理时间不满 0.1 小时之时，细粉热处理的效果不充分，这样就会和同没有氧化膜时一样，粉末间的附着力变高，这样的话， Br 、（ BH ） max 会变得极差。另外，也容易产生 AGG ，使矫顽力降低。
同时，在 700 ℃ 的温度下， 细粉热处理时间超过 24 小时之时，细粉粒子表面生成的氧化膜被吸收扩散到粒子内，结果就会同无氧化膜一样，会使氧含量增加， Br 、（ BH ） max 降低，极易产生（ AGG ），使矫顽力 Hcj 降低。
实施例4
原料配制过程：准备纯度 99.5% 的 Lu 、 Er 、 Nd 、 Tm 、 Y ，工业用 Fe-B ，工业用纯 Fe ，纯度 99.99% 的 Co ，纯度 99.5% 的 C 、 Cu 、 Mn 、 Ga 、 Bi 、 Ti ， 以原子百分比 at% 计，按照成分为 ReTfAgJhG iDk 来配制。
各元素的含量如下如：
R成分中，Lu为0.2，Er为0.2，Nd为13.5，Tm为0.1，Y为0.1；
T成分中，Fe 为余量，Co为1；
A成分中，C为0.05，B为7；
J成分中，Cu为0.2，Mn为0.2；
G成分中，Ga为0.2，Bi为0.1；
D成分中，Ti为1。
按照上述配制组成，合计称量、配制了500Kg的原料。
熔炼过程：取500Kg配制好的原料放入氧化铝制的坩埚中，在高频真空感应熔炼炉中在0.1Pa的真空中以1550℃以下的温度进行真空熔炼。
铸造过程：在真空熔炼后的熔炼炉中通入Ar气体使气压达到4万Pa后，使用甩带铸造法（SC）铸造成平均厚度为0.6mm的铸片。
氢破粉碎过程：将铸片放入内径为 ϕ 1200mm 的不锈钢制旋转式氢破炉容器中，容器抽真空使达到 10Pa 以下的真空 ，之后通入纯度为 99.999% 的氢气至压力为 0.12MPa ，容器按 2rpm 的旋转速度旋转 6 小时吸氢破碎，之后在 600℃ 的温度下抽 3 小时真空脱氢，而后按 10rpm 的旋转速度一边旋转容器一边冷却，取出冷却后的粗粉。
微粉碎过程：使用气流微粉碎机对粗粉进行微粉碎，获得平均粒径为 2μm 的细粉。
气流粉碎后的细粉分成 2 等份。
细粉热处理过程： 1 份细粉放入 ϕ1200mm 的不锈钢制旋转式氢破炉容器中，在容器中抽真空使达到 1Pa 以下的真空，之后往该容器中通入纯度为 99.9999% 的 Ar 气至压力为 1000Pa ， 控制 氧含量为 800 ～ 1000ppm ，露点为 -50 ℃ ～ -40 ℃ ，将容器放入外热型炉中进行加热，加热温度为 600℃ ，时间为 2 小时。加热时容器以 5rpm 的旋转速度进行旋转。
加热后，将容器从炉中取出，一边在外部进行水冷一边按 5rpm 的旋转速度进行旋转，冷却 5 小时。
磁场中成形过程：细粉热处理后的粉末中不添加有机添加剂，直接使用直角取向型的磁场成型机，在 1.8T 的取向磁场中，在 1.2ton/cm2 的成型压力下，一次成形为边长 40mm 的立方体，一次成形后在 0.2T 的磁场中退磁，为使一次成形后的成形体尽可能地不接触到空气将其进行密封，运至烧结炉。
烧结过程：将各成形体搬至烧结炉进行烧结，烧结在 10-3Pa 的真空下，在 200℃ 和 600℃ 的温度下各保持 2 小时后，在 0.02MPa 的 Ar 气体气氛中分别以 925℃ ～ 1150℃ 的温度烧结，之后通入 Ar 气体使气压达到 0.1MPa 后，冷却至室温。
热处理过程：烧结体在高纯度 Ar 气中，以 600℃ 温度进行 1 小时热处理后，冷却至室温后取出。
另 1 份细粉不进行热处理，作为比较例，按照除细粉热处理以外的相同制造条件依次进行上述磁场成形过程、烧结过程和热处理过程。
磁性能评价过程：烧结磁铁使用中国计量院的 NIM-10000H 型 BH 大块稀土永磁无损测量系统进行磁性能检测，评价平均值。
烧结体中的氧含量评价过程：烧结体中的氧含量使用日本 HORIBA 公司的 EMGA-620W 型氧氮分析仪进行检测。
有或无细粉热处理后在不同烧结温度情况下的实施例和比较例的磁性能评价和氧含量评价的情况如表 7 中所示。其中，序号 1-11 为未经热处理的细粉制成的烧结磁铁，序号 12-22 为经热处理的细粉制成的烧结磁铁。
表7 实施例和比较例的磁性能评价和氧含量评价的情况
序号 　 热处理 烧结温度（ ℃ ） 密度（ g/cc) Br(kGs) Hcj ( k0e) SQ(%) (BH)max(MG0e) 烧结体氧含量（ ppm ）
1 比较例 无 925 6.98 12.8 12.8 76.5 25.6 2840
2 比较例 无 950 7.21 13.4 12.3 93.2 39.8 2940
3 比较例 无 975 7.32 13.6 12.1 95.6 43.2 2850
4 比较例 无 1000 7.38 13.9 11.9 96.3 44.5 2840
5 比较例 无 1025 7.53 14.1 11.5 96.4 44.7 2840
6 比较例 无 1050 7.54 14.2 11.2 96.3 45.9 2870
7 比较例 无 1075 7.56 14.2 10.9 96.4 47.1 2780
8 比较例 无 1100 7.57 14.3 10.2 96.2 47.2 2790
9 比较例 无 1125 7.55 14.1 9.2 92.3 46.7 2830
10 比较例 无 1140 7.51 13.8 8.5 87.4 39.8 2840
11 比较例 无 1150 7.48 13.6 7.6 82.3 37.6 2980
12 比较例 有 925 7.23 13.8 9.8 81.2 45.3 982
13 本发明 有 950 7.47 14.4 13.8 97.8 50.1 354
14 本发明 有 975 7.49 14.4 13.6 98.2 50.2 341
15 本发明 有 1000 7.51 14.5 13.5 98.3 50.4 340
16 本发明 有 1025 7.54 14.5 13.4 98.4 50.4 342
17 本发明 有 1050 7.56 14.6 13.4 98.5 50.6 345
18 本发明 有 1075 7.59 14.6 13.4 98.6 50.8 343
19 本发明 有 1100 7.61 14.7 13.4 98.9 50.8 346
20 本发明 有 1125 7.64 14.7 13.4 99 51.1 347
21 本发明 有 1140 7.65 14.8 13.4 99.1 51.2 349
22 比较例 有 1150 7.32 13.4 12.2 76.5 38.4 768
从表 7 可以看出，通过细粉热处理，可以扩宽获得高性能的烧结温度范围。这是因为，防止了氧化就可以在低烧结温度下进行烧结，另一方面，在高温烧结时，同样不会发生晶粒异常长大（ AGG) ，这样一来，不管是低温烧结还是高温烧结都能获得很好的结果。
实施例5
原料配制过程：准备纯度 99.5% 的 Lu 、 Er 、 Nd 、 Tm 、 Y ，工业用 Fe-B ，工业用纯 Fe ，纯度 99.99% 的 Co ，纯度 99.5% 的 C 、 Cu 、 Mn 、 Ga 、 Bi 、 Ti ， 以原子百分比 at% 计，按照成分为 ReTfAgJhG iDk 来配制。
各元素的含量如下如：
R成分中，Lu为0.2，Er为0.2，Nd为13.5，Tm为0.1，Y为0.1；
T成分中，Fe 为余量，Co为1；
A成分中，C为0.05，B为7；
J成分中，Cu为0.2，Mn为0.2；
G成分中，Ga为0.2，Bi为0.1；
D成分中，Ti为1。
按照上述配制组成，合计称量、配制了500Kg的原料。
熔炼过程：取500Kg配制好的原料放入氧化铝制的坩埚中，在高频真空感应熔炼炉中在0.1Pa的真空中以1550℃以下的温度进行真空熔炼。
铸造过程：在真空熔炼后的熔炼炉中通入Ar气体使气压达到4万Pa后，使用甩带铸造法（SC）铸造成平均厚度为0.6mm的铸片。
氢破粉碎过程：将铸片放入内径为 ϕ1200mm 的不锈钢制旋转式氢破炉容器中，容器抽真空使达到 10Pa 以下的真空，之后通入纯度为 99.999% 的氢气至压力为 0.12MPa ，容器按 2rpm 的旋转速度旋转 6 小时吸氢破碎，之后在 600℃ 的温度下抽 3 小时真空脱氢，而后按 10rpm 的旋转速度一边旋转容器一边冷却，取出冷却后的粗粉。
微粉碎过程：使用气流微粉碎机对粗粉进行微粉碎，获得平均粒径为 2μm 的细粉。
细粉热处理过程：细粉放入 ϕ1200mm 的不锈钢制旋转式氢破炉容器中，在容器中抽真空使达到 1Pa 以下的真空，之后往该容器中通入纯度为 99.9999% 的 Ar 气至压力为 900Pa ， 控制 氧含量为 800 ～ 1000ppm ，露点为 -50 ℃ ～ -40 ℃ ，将容器放入外热型炉中进行加热，加热温度为 600℃ ，时间为 2 小时。加热时容器以 5rpm 的旋转速度进行旋转。
加热后，将容器从炉中取出，一边在外部进行水冷一边按 5rpm 的旋转速度进行旋转，冷却 5 小时。
磁场中成形过程：细粉热处理后的粉末中不添加有机添加剂，直接使用直角取向型的磁场成型机，在 1.8T 的取向磁场中，在 1.2ton/cm2 的成型压力下，一次成形为边长 40mm 的立方体，一次成形后在 0.2T 的磁场中退磁，为使一次成形后的成形体尽可能地不接触到空气将其进行密封，运至烧结炉。
烧结过程：将各成形体搬至烧结炉进行烧结，烧结在 10-3Pa 的真空下，在 200℃ 和 600℃ 的温度下各保持 2 小时后，在 0.02MPa 的 Ar 气体气氛中分别以 980℃ 的温度烧结，之后通入 Ar 气体使气压达到 0.1MPa 后，冷却至室温。
热处理过程：烧结体在高纯度 Ar 气中，以 600℃ 温度进行 1 小时热处理后，冷却至室温后取出。
加工及 RH 扩散过程：经过热处理的烧结体加工成 ϕ15mm 、厚度 5mm 的磁铁， 5mm 方向为磁场取向方向，加工后的磁铁洗净，表面洁净化后， 使用 Dy 氧化物和 Tb 氟化物按 3:1 比例配制成的原料，全面喷雾涂覆在磁铁上，将涂覆后的磁铁干燥，在高纯度 Ar 气体气氛中，以 680 ～ 1050℃ 的温度扩散热处理 12 小时。
磁性能评价过程：烧结磁铁使用中国计量院的 NIM-10000H 型 BH 大块稀土永磁无损测量系统进行磁性能检测，评价平均值。
烧结体中的氧含量评价过程：烧结体中的氧含量使用日本 HORIBA 公司的 EMGA-620W 型氧氮分析仪进行检测。
细粉热处理后在不同烧结温度情况下的实施例和比较例的磁性能评价和氧含量评价的情况如表 8 中所示。
表8 实施例和比较例的磁性能评价和氧含量评价的情况
序号 　 扩散温度（ ℃ ） 扩散时间（ hr ） 密度（ g/cc) Br （ kGs ） Hcj （ k0e ） SQ(%) (BH)max(MG0e) 烧结体氧含量（ ppm ）
1 比较例 680 8 7.49 13.5 11.3 81.1 43.2 972
2 本发明 700 8 7.50 14.0 19.8 98.2 46.6 954
3 本发明 750 8 7.52 14.2 20.8 98.6 47.2 941
4 本发明 800 6 7.52 14.2 21.3 98.3 46.8 940
5 本发明 850 6 7.51 14.4 22.1 99.4 47.6 942
6 本发明 900 4 7.51 14.2 22.5 99.5 46.6 945
7 本发明 950 4 7.52 14.2 23.0 99.6 46.2 943
8 本发明 1000 2 7.51 14.2 24.4 99.7 46.2 946
9 本发明 1020 2 7.52 14.2 24.4 99.3 46.1 947
10 比较例 1040 2 7.50 14.2 23.1 99.1 46.1 949
11 比较例 1050 2 7.49 13.4 18.7 79.8 42.8 968
从表 8 可以看出， 由于全部粉末表面均匀形成了氧化层，由此制成的磁铁晶界处氧的存在状态发生明显变化，重稀土元素的扩散速度变快，扩散效率高，可颠覆以往的常识，在较短的时间内完成晶界扩散。
本发明 通过细粉热处理，使粉末的性能发生剧变，烧结后将磁铁加工为期望的尺寸，进行晶界扩散处理，本发明中，在 680 ℃ ～ 1050 ℃ 的温度下进行了晶界扩散试验，确认 700℃ ～ 1020℃ 作为其晶界扩散温度，并以 1000 ℃ ～ 1020 ℃ 区间 为最合适的 Dy 晶界扩散处理温度。
现有的常识认为，片厚为 5mm 的磁铁需要进行晶界扩散时，一般需要在 800 ℃ ～ 950 ℃的温度区间下 扩散 10 小时以上，才能获得良好的矫顽力改善效果，提高扩散温度虽然有助于缩短扩散时间，但是容易引发磁铁变形、表面融化、以及 AGG 等的问题，且使得扩散在晶界相和主相扩散同时进行，导致磁铁性能降低。而本发明的磁铁在以 1000 ℃ ～ 1020 ℃ 区间进行扩散，仅需扩散 2 小时，就能在不引发上述问题的前提下获得良好的矫顽力改善效果，大大缩短了生产周期。
上述实施例仅用来进一步说明本发明的几种具体的实施方式，但本发明并不局限于实施例，凡是依据本发明的技术实质对以上实施例所作的任何简单修改、等同变化与修饰，均落入本发明技术方案的保护范围内。
工业实用性
本发明基于细粉热处理的稀土磁铁制造方法，其是在微粉碎工序之后，磁场中成形工序之前，增加细粉热处理工序，由于在全部粉末表面均匀形成了氧化层，制得的磁铁晶界处氧的存在状态发生明显变化，重稀土元素的扩散速度变快，效率提高，可在较短的时间内完成晶界扩散。该方法可以在工业上实用，具有工业实用性。

Claims (10)

  1. 基于细粉热处理的稀土磁铁制造方法，所述的稀土磁铁为含有R2 T14 B主相的磁铁，所述的R为选自包含钇元素在内的稀土元素中的至少一种，所述T为包括Fe的至少一种过渡金属元素，其特征在于，包括如下的步骤：将稀土磁铁用合金粗粉碎后再通过气流磨微粉碎制成细粉，所述细粉在真空或惰性气体气氛中以100℃～1000℃的温度进行6分钟以上24小时以下的热处理，之后使用磁场成形法进行成形，在真空或惰性气体中以950℃～1140℃的温度进行烧结，获得稀土磁铁烧结体；以及
    对所述稀土磁铁烧结体进行加工，获得磁铁，之后对磁铁在700℃～1020℃的温度下进行RH晶界扩散处理工序。
  2. 根据权利要求1所述的基于细粉热处理的稀土磁铁制造方法，其特征在于：所述RH晶界扩散处理的温度为1000℃～1020℃。
  3. 根据权利要求2所述的基于细粉热处理的稀土磁铁制造方法，其特征在于：所述的细粉热处理的温度为300℃～700℃。
  4. 根据权利要求3所述的基于细粉热处理的稀土磁铁制造方法，其特征在于：所述细粉热处理工序中，对所述细粉进行振动或摇动。
  5. 根据权利要求1或2所述的基于细粉热处理的稀土磁铁制造方法，其特征在于：所述真空状态热处理工序中，压力在10-2 Pa～500Pa ，氧含量为0.5ppm～2000ppm，露点为-60℃～20℃。
  6. 根据权利要求1或2或3所述的基于细粉热处理的稀土磁铁制造方法，其特征在于：所述惰性气体气氛热处理工序中，压力在10-1 Pa～1000Pa ，氧含量为0.5ppm～2000ppm，露点为-60℃～20℃。
  7. 根据权利要求3所述的基于细粉热处理的稀土磁铁制造方法，其特征在于：所述稀土磁铁用合金是将原料合金熔融液用带材铸件法，以102 ℃/秒以上、104 ℃/秒以下的冷却速度冷却得到的。
  8. 根据权利要求1或2或3所述的基于细粉热处理的稀土磁铁制造方法，其特征在于：所述粗粉碎过程是将稀土磁铁用合金在0.01MPa以上、1MPa以下的氢气压力下保持0.5～6小时进行氢破粉碎，之后抽真空脱氢的过程。
  9. 根据权利要求3所述的基于细粉热处理的稀土磁铁制造方法，其特征在于：所述稀土磁铁用合金以原子百分比计，其成分为Re Tf AgJh Gi Dk ，其中，R为Nd或包含Nd和选自La、Ce、Pr、Sm、Gd、Dy、Tb、Ho、Er、Eu、Tm、Lu或Y中的至少一种，T为Fe或包含Fe和选自Ru、Co或Ni中的至少一种，A为B或包含B和选自C或P中的至少一种，J为选自Cu、Mn、Si或Cr中的至少一种，G为选自Al、Ga、Ag、Bi或Sn中的至少一种，D为选自Zr、Hf、V、Mo、W、Ti或Nb中的至少一种；以及
    e的原子百分比at%为12≤e≤16，
    g的原子百分比at%为5≤g≤9，
    h的原子百分比at%为0.05≤h≤1，
    i的原子百分比at%为0.2≤i≤2.0，
    k的原子百分比at%为0≤j≤4，
    f的原子百分比at%为f＝100-e-g-h-i-k。
  10. 根据权利要求1或2或3所述的基于细粉热处理的稀土磁铁制造方法，其特征在于：所述细粉经过热处理全部粉末表面均匀形成了氧化层。
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Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20180294081A1 (en) * 2015-09-28 2018-10-11 Xiamen Tungsten Co., Ltd. COMPOSITE R-Fe-B SERIES RARE EARTH SINTERED MAGNET COMPRISING Pr AND W
CN112420372A (zh) * 2020-11-23 2021-02-26 浙江英洛华磁业有限公司 一种稀土永磁体材料的制备方法
CN115116734A (zh) * 2022-07-21 2022-09-27 宁波松科磁材有限公司 一种改善晶界扩散制备高性能钕铁硼永磁材料的方法

Families Citing this family (21)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103050267B (zh) * 2012-12-31 2016-01-20 厦门钨业股份有限公司 一种基于细粉热处理的烧结Nd-Fe-B系磁铁制作方法
CN103258609B (zh) * 2013-05-14 2016-08-10 深圳大学 各向异性纳米复相稀土永磁材料的制备方法
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CN103831435B (zh) * 2014-01-27 2018-05-18 厦门钨业股份有限公司 磁体合金粉末与其磁体的制造方法
CN104952574A (zh) 2014-03-31 2015-09-30 厦门钨业股份有限公司 一种含W的Nd-Fe-B-Cu系烧结磁铁
CN104538169B (zh) * 2015-01-17 2017-05-24 惠安盛泽建材有限公司 一种钴基磁芯的制备方法
CN104851545B (zh) * 2015-05-21 2017-11-17 王怡 一种具有晶界扩散层的永磁材料制备方法
JP2018056188A (ja) 2016-09-26 2018-04-05 信越化学工業株式会社 Ｒ−Ｆｅ−Ｂ系焼結磁石
CN106783131B (zh) * 2016-12-23 2019-03-26 宁波韵升股份有限公司 一种烧结钕铁硼薄片磁体的制备方法
CN106929764B (zh) * 2017-04-11 2018-07-03 西北工业大学 一种纳米晶/超细晶双相双峰块体材料及制备方法
CN110753978B (zh) * 2017-05-19 2021-09-28 罗伯特·博世有限公司 热变形磁体以及制备所述热变形磁体的方法
CN110619984B (zh) * 2018-06-19 2021-12-07 厦门钨业股份有限公司 一种低B含量的R-Fe-B系烧结磁铁及其制备方法
JP7260304B2 (ja) * 2019-01-11 2023-04-18 トヨタ自動車株式会社 軟磁性部材の製造方法
WO2021063479A1 (en) * 2019-09-30 2021-04-08 Dimitrios Niarchos Rare-earth high entropy alloys and transition metal high entropy alloys as building blocks for the synthesis of new magnetic phases for permanent magnets
CN110993232B (zh) * 2019-12-04 2021-03-26 厦门钨业股份有限公司 一种r-t-b系永磁材料、制备方法和应用
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Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101238530A (zh) * 2005-08-08 2008-08-06 日立金属株式会社 稀土类合金系无粘结剂磁铁及其制造方法
CN102103916A (zh) * 2009-12-17 2011-06-22 北京有色金属研究总院 一种钕铁硼磁体的制备方法
CN102274974A (zh) * 2011-06-01 2011-12-14 横店集团东磁股份有限公司 一种纳米晶稀土永磁合金粉末的制备方法
CN102586682A (zh) * 2011-01-17 2012-07-18 三环瓦克华（北京）磁性器件有限公司 一种高性能稀土永磁烧结磁体及其制造方法
CN103050267A (zh) * 2012-12-31 2013-04-17 厦门钨业股份有限公司 一种基于细粉热处理的烧结Nd-Fe-B系磁铁制作方法

Family Cites Families (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH04221005A (ja) * 1990-12-20 1992-08-11 Sumitomo Metal Mining Co Ltd 還元拡散法を利用した希土類金属を含む合金粉末の製造方法
DE69420474T2 (de) * 1993-06-30 2000-05-18 Applied Materials Inc Verfahren zum Spülen und Auspumpen einer Vakuumkammer bis Ultra-Hoch-Vakuum
JP2001524604A (ja) * 1997-11-20 2001-12-04 インスティトゥート フュア フェストケルパー− ウント ヴェルクシュトッフオルシュング ドレースデン エー ファウ 磁気合金粉末の製法
US6511552B1 (en) 1998-03-23 2003-01-28 Sumitomo Special Metals Co., Ltd. Permanent magnets and R-TM-B based permanent magnets
EP1749599B1 (en) * 2004-04-30 2015-09-09 Hitachi Metals, Ltd. Methods for producing raw material alloy for rare earth magnet, powder and sintered magnet
CN101981634B (zh) * 2008-03-31 2013-06-12 日立金属株式会社 R-t-b系烧结磁体及其制造方法
JP4835758B2 (ja) * 2009-03-30 2011-12-14 Ｔｄｋ株式会社 希土類磁石の製造方法
JP5381435B2 (ja) * 2009-07-14 2014-01-08 富士電機株式会社 永久磁石用磁石粉末の製造方法、永久磁石粉末及び永久磁石
JP5059955B2 (ja) * 2010-04-15 2012-10-31 住友電気工業株式会社 磁石用粉末
CN101819841A (zh) * 2010-05-17 2010-09-01 上海交通大学 钕铁硼磁性材料及其制备方法
CN102682987B (zh) * 2011-03-15 2016-12-07 北京中科三环高技术股份有限公司 稀土永磁体的制备方法、制备装置及其制备的稀土永磁体

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101238530A (zh) * 2005-08-08 2008-08-06 日立金属株式会社 稀土类合金系无粘结剂磁铁及其制造方法
CN102103916A (zh) * 2009-12-17 2011-06-22 北京有色金属研究总院 一种钕铁硼磁体的制备方法
CN102586682A (zh) * 2011-01-17 2012-07-18 三环瓦克华（北京）磁性器件有限公司 一种高性能稀土永磁烧结磁体及其制造方法
CN102274974A (zh) * 2011-06-01 2011-12-14 横店集团东磁股份有限公司 一种纳米晶稀土永磁合金粉末的制备方法
CN103050267A (zh) * 2012-12-31 2013-04-17 厦门钨业股份有限公司 一种基于细粉热处理的烧结Nd-Fe-B系磁铁制作方法

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20180294081A1 (en) * 2015-09-28 2018-10-11 Xiamen Tungsten Co., Ltd. COMPOSITE R-Fe-B SERIES RARE EARTH SINTERED MAGNET COMPRISING Pr AND W
US10971289B2 (en) * 2015-09-28 2021-04-06 Xiamen Tungsten Co., Ltd. Composite R-Fe-B series rare earth sintered magnet comprising Pr and W
CN112420372A (zh) * 2020-11-23 2021-02-26 浙江英洛华磁业有限公司 一种稀土永磁体材料的制备方法
CN115116734A (zh) * 2022-07-21 2022-09-27 宁波松科磁材有限公司 一种改善晶界扩散制备高性能钕铁硼永磁材料的方法
CN115116734B (zh) * 2022-07-21 2024-02-02 宁波松科磁材有限公司 一种改善晶界扩散制备高性能钕铁硼永磁材料的方法

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