WO2011108704A1 - 希土類焼結磁石及びモータ - Google Patents
希土類焼結磁石及びモータ Download PDFInfo
- Publication number
- WO2011108704A1 WO2011108704A1 PCT/JP2011/055067 JP2011055067W WO2011108704A1 WO 2011108704 A1 WO2011108704 A1 WO 2011108704A1 JP 2011055067 W JP2011055067 W JP 2011055067W WO 2011108704 A1 WO2011108704 A1 WO 2011108704A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- rare earth
- sintered magnet
- earth sintered
- magnet body
- slurry
- Prior art date
Links
Images
Classifications
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02K—DYNAMO-ELECTRIC MACHINES
- H02K1/00—Details of the magnetic circuit
- H02K1/02—Details of the magnetic circuit characterised by the magnetic material
-
- 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
- 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
- B22F3/24—After-treatment of workpieces or articles
-
- 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
- B22F9/00—Making metallic powder or suspensions thereof
- B22F9/02—Making metallic powder or suspensions thereof using physical processes
- B22F9/023—Hydrogen absorption
-
- 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
- B22F9/00—Making metallic powder or suspensions thereof
- B22F9/02—Making metallic powder or suspensions thereof using physical processes
- B22F9/04—Making metallic powder or suspensions thereof using physical processes starting from solid material, e.g. by crushing, grinding or milling
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C33/00—Making ferrous alloys
- C22C33/02—Making ferrous alloys by powder metallurgy
- C22C33/0257—Making ferrous alloys by powder metallurgy characterised by the range of the alloying elements
- C22C33/0278—Making ferrous alloys by powder metallurgy characterised by the range of the alloying elements with at least one alloying element having a minimum content above 5%
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- 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
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/005—Ferrous alloys, e.g. steel alloys containing rare earths, i.e. Sc, Y, Lanthanides
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/06—Ferrous alloys, e.g. steel alloys containing aluminium
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/10—Ferrous alloys, e.g. steel alloys containing cobalt
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/16—Ferrous alloys, e.g. steel alloys containing copper
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
- H01F1/00—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties
- H01F1/01—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials
- H01F1/03—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity
- H01F1/032—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of hard-magnetic materials
- H01F1/04—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of hard-magnetic materials metals or alloys
- H01F1/047—Alloys characterised by their composition
- H01F1/053—Alloys characterised by their composition containing rare earth metals
- H01F1/055—Alloys characterised by their composition containing rare earth metals and magnetic transition metals, e.g. SmCo5
- H01F1/057—Alloys characterised by their composition containing rare earth metals and magnetic transition metals, e.g. SmCo5 and IIIa elements, e.g. Nd2Fe14B
- H01F1/0571—Alloys characterised by their composition containing rare earth metals and magnetic transition metals, e.g. SmCo5 and IIIa elements, e.g. Nd2Fe14B in the form of particles, e.g. rapid quenched powders or ribbon flakes
- H01F1/0575—Alloys characterised by their composition containing rare earth metals and magnetic transition metals, e.g. SmCo5 and IIIa elements, e.g. Nd2Fe14B in the form of particles, e.g. rapid quenched powders or ribbon flakes pressed, sintered or bonded together
- H01F1/0577—Alloys characterised by their composition containing rare earth metals and magnetic transition metals, e.g. SmCo5 and IIIa elements, e.g. Nd2Fe14B in the form of particles, e.g. rapid quenched powders or ribbon flakes pressed, sintered or bonded together sintered
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
- H01F41/00—Apparatus or processes specially adapted for manufacturing or assembling magnets, inductances or transformers; Apparatus or processes specially adapted for manufacturing materials characterised by their magnetic properties
- H01F41/02—Apparatus or processes specially adapted for manufacturing or assembling magnets, inductances or transformers; Apparatus or processes specially adapted for manufacturing materials characterised by their magnetic properties for manufacturing cores, coils, or magnets
- H01F41/0253—Apparatus or processes specially adapted for manufacturing or assembling magnets, inductances or transformers; Apparatus or processes specially adapted for manufacturing materials characterised by their magnetic properties for manufacturing cores, coils, or magnets for manufacturing permanent magnets
- 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
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
- H01F7/00—Magnets
- H01F7/02—Permanent magnets [PM]
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02K—DYNAMO-ELECTRIC MACHINES
- H02K15/00—Methods or apparatus specially adapted for manufacturing, assembling, maintaining or repairing of dynamo-electric machines
- H02K15/02—Methods or apparatus specially adapted for manufacturing, assembling, maintaining or repairing of dynamo-electric machines of stator or rotor bodies
- H02K15/03—Methods or apparatus specially adapted for manufacturing, assembling, maintaining or repairing of dynamo-electric machines of stator or rotor bodies having permanent magnets
-
- 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 a rare earth sintered magnet and a motor obtained by attaching a rare earth compound to a rare earth sintered magnet body and heat-treating the rare earth compound.
- a rare earth sintered magnet having a composition of R—Fe—B (R is a rare earth element) is a magnet having excellent magnetic properties.
- R is a rare earth element
- a method for producing such a rare earth magnet there is a method in which a slurry containing a rare earth is applied (attached) to a sintered body and then subjected to heat treatment.
- a slurry containing a rare earth is applied (attached) to a sintered body and then subjected to heat treatment.
- Patent Document 1 in a state where a powder containing rare earth elements including Y and Sc is present on the surface of the sintered magnet body, the sintered magnet body and the powder are below the sintering temperature of the sintered magnet body.
- Patent Document 1 describes a method of putting a sintered magnet body into a slurry in which the powder is dispersed in water or an organic solvent as a method for attaching a powder containing a rare earth element to the sintered magnet body.
- the thickness of the applied slurry varies depending on the position of the surface, and unevenness may occur. If there is unevenness in the adhering slurry (the amount of adhering rare earth compound) in this way, then in the magnet manufactured by heat treatment, the surface magnetic flux will vary, and the magnetic characteristics such as residual magnetic flux density Br will be uneven. There was a problem of doing.
- the present invention has been made in view of the above, and an object thereof is to provide a rare earth sintered magnet in which unevenness of magnetic properties is suppressed.
- the present invention provides (R1, R2) 2 T 14 B (R1 is at least one rare earth element excluding Dy and Tb, and R2 represents Dy and Tb.
- R1 is at least one rare earth element excluding Dy and Tb
- R2 represents Dy and Tb.
- a rare earth sintered magnet having a rare earth sintered magnet body including crystal grains of a rare earth element including at least one or both, wherein T represents one or more transition metal elements including Fe or Fe and Co.
- the ratio of R2 to the sum of R1 and R2 contained in the crystal grain boundary surrounding the crystal grains in the rare earth sintered magnet body is greater than the ratio of R2 to the sum of R1 and R2 in the crystal grains.
- the concentration of R2 increases from the center of the rare earth sintered magnet body toward the surface of the rare earth sintered magnet body, and the variation in the residual magnetic flux density Br on the surface of the rare earth sintered magnet body is less than 3.0%. It is characterized by Rare earth sintered magnet.
- R1, R2 The rare earth sintered magnet body in a state in which a slurry containing a rare earth compound of R2 is present on the surface of the rare earth sintered magnet body in the rare earth sintered magnet body containing 2 T 14 B crystal grains.
- the slurry is then heat treated to absorb the R2 rare earth compound contained in the slurry.
- the R2 rare earth compound contained in the slurry existing on the surface of the sintered magnet body is taken into the rare earth sintered magnet body through the crystal grain boundaries (grain boundaries of crystal grains), It diffuses inside the crystal grains.
- the ratio of R2 to the sum of R1 and R2 included in the crystal grain boundary surrounding the (R1, R2) 2 T 14 B crystal grains in the rare earth sintered magnet body is such that R1 in the crystal grains And R2 with respect to the sum of R2 and R2. Since the R-rich layer at the grain boundary is liquefied by heating, the diffusion rate of R2 in the crystal grain boundary is considered to be faster than the diffusion rate from the grain boundary to the inside of the crystal grain. Also, heat treatment is performed at a temperature below the sintering temperature of the rare earth sintered magnet body, so that the R2 rare earth compound diffuses into the crystal grain boundaries of the rare earth sintered magnet body and diffuses into the crystal grains. do not do.
- R2 diffuses in the vicinity of the grain boundary of the rare earth sintered magnet body.
- R2 rare earth compound is applied to the surface of the rare earth sintered magnet body and supplied, R2 is distributed more on the surface side of the rare earth sintered magnet body than inside the rare earth sintered magnet body. Therefore, the concentration of R2 is distributed so as to increase from the center of the rare earth sintered magnet body toward the surface of the rare earth sintered magnet body.
- the R2 rare earth compound is taken from the surface of the rare earth sintered magnet body through the grain boundaries into the rare earth sintered magnet body and diffused from the grain boundaries to the inside of each crystal grain, and R2 is introduced in the vicinity of the grain boundaries of the crystal grains. Spread.
- the ratio of R2 to the sum of R1 and R2 contained in the crystal grain boundary in the rare earth sintered magnet body is such that R2 is relative to the sum of R1 and R2 in the crystal grain. Higher than the rate.
- the rare earth sintered magnet of the present invention can increase the coercive force HcJ of the magnet with almost no decrease in the residual magnetic flux density Br.
- the variation of the residual magnetic flux density Br on the surface of the rare earth sintered magnet body is less than 3.0%.
- the rare earth sintered magnet after the heat treatment can suppress variations in the magnetic flux on the surface thereof, and can suppress unevenness in magnetic characteristics such as residual magnetic flux density Br.
- the rare earth sintered magnet of the present invention when used as a permanent magnet for a motor, the cogging torque of the motor can be reduced.
- the variation in coercive force HcJ on the surface of the rare earth sintered magnet body is preferably less than 18.0%.
- the demagnetization temperature at which the rare earth sintered magnet begins to demagnetize can be increased. For this reason, when a rare earth sintered magnet is used as a permanent magnet for a motor, the heat resistance of the permanent magnet can be improved.
- the rare earth sintered magnet body has a plurality of surfaces, and the surface of the plurality of surfaces of the rare earth sintered magnet body that minimizes the variation in the residual magnetic flux density Br is the rare earth sintered magnet.
- a plane perpendicular to the body orientation direction is preferred.
- the surface of the rare earth sintered magnet body in which the variation of the residual magnetic flux density Br is smaller than the other surfaces of the rare earth sintered magnet body is a surface perpendicular to the orientation direction of the rare earth sintered magnet body. The variation of is small. For this reason, since the rare earth sintered magnet of the present invention can improve motor performance such as torque characteristics of the motor, it can be suitably used as a permanent magnet for a motor.
- the present invention relates to (R1, R2) 2 T 14 B (R1 is at least one rare earth element excluding Dy and Tb, R2 is a rare earth element containing at least one of or both of Dy and Tb, Represents a one or more transition metal elements including Fe or Fe and Co) and rotates a rare earth sintered magnet body including a crystal grain of R2 and applies a slurry containing a R2 rare earth compound to the rare earth sintered magnet body, Crystal grains surrounding the crystal grains in the rare earth sintered magnet body obtained by heat-treating the rare earth sintered magnet body with the slurry dried while rotating the rare earth sintered magnet body.
- the ratio of R2 to the sum of R1 and R2 contained in the boundary is higher than the ratio of R2 to the sum of R1 and R2 in the crystal grains, and the concentration of R2 is rare earth sintered magnet from the center of the rare earth sintered magnet body.
- the rare earth sintered magnet is characterized in that the variation in residual magnetic flux density on the surface of the rare earth sintered magnet body is less than 3.0%.
- the slurry By supplying the slurry containing the R2 rare earth compound toward the rare earth sintered magnet body while rotating the rare earth sintered magnet body, the slurry can be uniformly applied to the entire rare earth sintered magnet body.
- the rare earth sintered magnet of the present invention takes in the R2 rare earth compound from the surface of the rare earth sintered magnet body into the rare earth sintered magnet body through the grain boundaries, and from the grain boundaries, While diffusing inside, R2 is diffused in the vicinity of the grain boundaries of the crystal grains.
- the rare earth sintered magnet of the present invention can increase the coercive force HcJ of the magnet with almost no decrease in the residual magnetic flux density Br.
- the variation of the residual magnetic flux density Br on the surface of the rare earth sintered magnet body is set to less than 3.0%.
- the rare earth sintered magnet manufactured by heat treatment as described above can suppress variations in magnetic flux on the surface thereof, and can suppress uneven magnetic properties such as residual magnetic flux density Br. For this reason, when the rare earth sintered magnet of the present invention is used as a permanent magnet for a motor, the cogging torque of the motor can be reduced.
- the slurry applied to the rare earth sintered magnet body is dried, so that the unevenness of the thickness of the applied slurry can be more reliably suppressed.
- the slurry is preferably sprayed onto the rare earth sintered magnet body by spraying and applied to the rare earth sintered magnet body.
- the slurry can be more uniformly applied to the entire area in the axial direction of the rare earth sintered magnet body.
- the present invention it is preferable to immerse the rare earth sintered magnet body in a region where the slurry is stored and apply the slurry to the rare earth sintered magnet body.
- the slurry can be easily and uniformly applied to the entire area of the rare earth sintered magnet body.
- the slurry is preferably applied to the rare earth sintered magnet body as a plurality of slurry streams.
- the slurry can be uniformly applied to the entire area of the rare earth sintered magnet body in the axial direction.
- the slurry is applied to the rare earth sintered magnet body by dropping from the upper position in the vertical direction of the arrangement position of the rare earth sintered magnet body. Since the slurry is applied to the rare earth sintered magnet body by dropping from the vertical direction above the position where the rare earth sintered magnet body is disposed, the slurry is simply and uniformly applied to the entire area of the rare earth sintered magnet body in the axial direction. be able to.
- the motor of the present invention comprises the rare earth sintered magnet of the present invention, and is provided with a stator having a plurality of coils arranged in the circumferential direction, rotatably provided in the stator, and on the outer circumferential surface. And a rotor having a rotor core on which the rare earth sintered magnet described in any one of the above is provided at a predetermined interval. Since the motor of the present invention uses a rare earth sintered magnet with suppressed magnetic property unevenness as a permanent magnet, cogging torque, torque ripple, and the like can be reduced, and motor performance can be improved.
- the present invention it is possible to provide a rare earth sintered magnet in which unevenness of magnetic properties is suppressed. Moreover, motor performance can be improved by using the said rare earth sintered magnet for a motor.
- FIG. 1 is a flowchart showing a method for manufacturing a rare earth sintered magnet according to an embodiment of the present invention.
- FIG. 2 is a diagram schematically illustrating the configuration of the magnet manufacturing apparatus.
- FIG. 3 is a flowchart showing a method of manufacturing a rare earth sintered magnet body used for manufacturing the rare earth sintered magnet according to the embodiment of the present invention.
- FIG. 4 is a schematic diagram schematically showing the configuration of the coating mechanism.
- FIG. 5 is a schematic diagram schematically showing the configuration of the coating means.
- FIG. 6 is an explanatory view simply showing another configuration in which slurry is applied to the rare earth sintered magnet body.
- FIG. 7 is an explanatory view simply showing another configuration in which slurry is applied to a rare earth sintered magnet body.
- FIG. 6 is an explanatory view simply showing another configuration in which slurry is applied to the rare earth sintered magnet body.
- FIG. 8 is a longitudinal sectional view schematically showing the configuration of an embodiment of the motor.
- FIG. 9 is a diagram schematically showing a cross section in the AA direction in FIG.
- FIG. 10 is a view showing an example of a processing container used for vapor-depositing DyH 2 on the surface of a rare earth sintered magnet body.
- FIG. 11 is an explanatory view showing each region of the sintered body.
- FIG. 12 is a cross-sectional view schematically showing an example of the configuration of the motor used in the magnetic field analysis simulation.
- the rare earth sintered magnet according to this embodiment is (R1, R2) 2 T 14 B (R1 is at least one kind of rare earth element excluding Dy and Tb, and R2 is at least one or both of Dy and Tb. It is a rare earth sintered magnet having a rare earth sintered magnet body including crystal grains of a rare earth element including T and T represents one or more transition metal elements including Fe and Co. Further, in the rare earth sintered magnet according to the present embodiment, the ratio of R2 to the sum of R1 and R2 included in the crystal grain boundary surrounding the crystal grains in the rare earth sintered magnet body is R1 in the crystal grains. It is higher than the ratio of R2 with respect to the sum of R2, and the concentration of R2 is made higher from the rare earth sintered magnet body central portion toward the rare earth sintered magnet body surface.
- the composition of crystal grains contained in the main phase of the RTB-based rare earth sintered magnet is represented by a composition formula of (R1, R2) 2 T 14 B.
- This main phase has a crystal structure made of (R1, R2) 2 T 14 B type tetragonal crystals. Therefore, R representing the composition of the main phase of the RTB-based rare earth sintered magnet is a general term for R1 and R2.
- R represents at least one rare earth element
- R1 represents at least one rare earth element excluding Dy and Tb
- R2 represents a rare earth element including at least one or both of Dy and Tb
- T represents One or more transition metal elements including Fe or Fe and Co are represented.
- the rare earth sintered magnet includes both a magnet product obtained by processing the magnet and magnetized and the magnet not magnetized.
- the crystal grain boundary may include a rare earth-rich phase with a high mixing ratio of rare earth elements and a boron-rich phase with a high mixing ratio of boron (B) atoms.
- the crystal grain size is usually about 1 ⁇ m to 30 ⁇ m.
- the rare earth sintered magnet according to the present embodiment is obtained by subjecting the rare earth sintered magnet body and the slurry to heat treatment in a state in which the slurry containing the R2 rare earth compound is present on the surface of the rare earth sintered magnet body.
- the rare earth sintered magnet body in which the R2 rare earth compound is absorbed is used.
- the R2 rare earth compound contained in the slurry present on the surface of the sintered magnet body is taken into the rare earth sintered magnet body through the grain boundaries, and is mainly introduced from the grain boundaries. It diffuses inside each crystal grain of the phase.
- the diffusion rate of R2 in the grain boundary is considered to be faster than the diffusion rate from the grain boundary to the inside of the crystal grain.
- R2 diffuses in the vicinity of the grain boundaries of the rare earth sintered magnet body. .
- the ratio of R2 to the sum of R1 and R2 included in the crystal grain boundary is higher than the ratio of R2 to the sum of R1 and R2 in the crystal grain.
- the R2 rare earth compound is applied to the surface of the rare earth sintered magnet body and supplied to the inside of the rare earth sintered magnet body, there is more R2 on the surface side of the rare earth sintered magnet body than inside the rare earth sintered magnet body. Distributed. Therefore, the concentration of R2 increases from the center of the rare earth sintered magnet body toward the surface of the rare earth sintered magnet body.
- the R2 rare earth compound is taken from the surface of the rare earth sintered magnet body into the rare earth sintered magnet body through the crystal grain boundary, and is diffused from the crystal boundary to the inside of each crystal grain. R2 is diffused in the vicinity of the grain boundaries of the crystal grains. For this reason, the rare earth sintered magnet according to the present embodiment can improve the coercive force HcJ with almost no decrease in the residual magnetic flux density Br as compared with the case where R2 is added from the alloy.
- the rare earth compound of R2 contained in the slurry When the rare earth compound of R2 contained in the slurry is absorbed by the rare earth sintered magnet body, heat treatment is performed in a vacuum or an inert gas atmosphere such as Ar (argon) or helium (He). In an atmosphere where the processing chamber is close to atmospheric pressure, the R2 rare earth compound contained in the slurry is less likely to be supplied into the sintered magnet body.
- the R2 rare earth compound of the sintered magnet body is reduced by reducing the pressure in the processing chamber to a vacuum or an inert gas atmosphere and a pressure lower than the atmosphere. It becomes easy to be supplied from the surface to the inside. Thereby, the coercive force HcJ of the rare earth sintered magnet can be improved.
- the heat treatment temperature at the time of heat treatment is a temperature below the sintering temperature of the rare earth sintered magnet body. This is because if the heat treatment is performed at a temperature higher than the sintering temperature of the rare earth sintered magnet body, the structure of the rare earth sintered magnet may be transformed. Further, the R2 rare earth compound diffuses not only to the crystal grain boundary of the rare earth sintered magnet body but also to the inside of the crystal grain, and there is a possibility that the residual magnetic flux density Br on the surface of the rare earth sintered magnet body may be reduced.
- the variation in the residual magnetic flux density Br in the plane perpendicular to the orientation direction of the rare earth sintered magnet body is less than 3.0%, preferably 2.5% or less, more preferably 2.0%. It is.
- the variation in the residual magnetic flux density Br on the surface perpendicular to the orientation direction of the rare earth sintered magnet body is 3.0% or more, the rare earth sintered magnet manufactured by heat treatment has a large variation in the magnetic flux on the surface.
- the cogging torque cannot be reduced.
- the variation in the residual magnetic flux density Br is extracted as a sample piece from a plurality of locations on the surface of the rare earth sintered magnet body, and the residual magnetic flux density Br of each sample piece is measured.
- the residual magnetic flux density Br is measured by attaching a sample piece taken out from the surface of the rare earth sintered magnet body to an acrylic rod and measuring it using a vibrating sample magnetometer (VSM: Vibrating Sample Magnetometer). Is measured.
- VSM Vibrating Sample Magnetometer
- the thickness of the slurry to be applied varies depending on the position of the surface, resulting in unevenness.
- the variation in the residual magnetic flux density Br on the surface perpendicular to the orientation direction of the manufactured magnet was also large.
- the slurry containing the R2 rare earth compound is applied to the surface of the rare earth sintered magnet body while rotating the rare earth sintered magnet body. Variation in the thickness of the slurry applied to the surface can be reduced.
- vertical to the orientation direction of a rare earth sintered magnet body can be made into the said range.
- the nonuniformity of the magnetic characteristics of the magnet can be further suppressed.
- the rare earth sintered magnet according to the present embodiment is used as a permanent magnet of a motor, for example, the cogging torque of the motor can be reduced.
- the diffusion amount of the R2 rare earth compound in the rare earth sintered magnet body is different in the planar direction of the rare earth sintered magnet body. Since they are different, the coercive force HcJ on the surface of the rare earth sintered magnet body is different.
- the variation in the thickness of the slurry applied to the surface of the rare earth sintered magnet body the variation in the diffusion amount of the R2 rare earth compound in the rare earth sintered magnet body in the plane direction of the rare earth sintered magnet body is reduced. .
- variation in the coercive force HcJ in the surface of a rare earth sintered magnet body can be reduced.
- the variation of the coercive force HcJ on the surface of the rare earth sintered magnet body is preferably less than 18.0%, more preferably 15% or less, and even more preferably 10% or less.
- the variation of the coercive force HcJ on the surface of the rare earth sintered magnet body is 18.0% or more, when the rare earth sintered magnet manufactured by heat treatment is used as a magnet for a motor, sufficient heat resistance is obtained. It is because it cannot have.
- the demagnetization temperature at which the rare earth sintered magnet begins to demagnetize can be increased.
- the heat resistance of a permanent magnet can be improved.
- the variation in the coercive force HcJ is extracted as a sample piece from a plurality of locations on the surface of the rare earth sintered magnet body, and the coercive force HcJ of each sample piece is measured. And the average value of the value of the coercive force HcJ of the measured sample piece is calculated
- a value obtained by dividing the value of the difference between the measured coercive force HcJ and the average value by the average value and multiplying by 100 is defined as the variation in the coercive force HcJ.
- the coercive force HcJ is measured by a pulse BH tracer.
- the R includes at least one rare earth element as described above.
- Rare earth elements refer to Sc, Y, and lanthanoid elements belonging to Group 3 of the long-period periodic table. Examples of lanthanoid elements include La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, etc. are included.
- the rare earth elements are classified into light rare earth elements and heavy rare earth elements.
- the heavy rare earth elements are Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu, and the light rare earth elements are other rare earth elements. From the viewpoint of magnetic characteristics, it is preferable that R1 contains one or both of Nd and Pr as a main component.
- R2 preferably contains a heavy rare earth element, particularly one or both of Dy and Tb, and may further contain Ho.
- the heavy rare earth element has an effect of increasing the anisotropic magnetic field of the rare earth sintered magnet, and can improve the coercive force of the magnet.
- the T is selected from the group consisting of transition elements other than Fe, such as Co, Ti, V, Cr, Mn, Ni, Cu, Zr, Nb, Mo, Hf, Ta, and W, other than rare earth elements. It may further contain at least one kind of element.
- the T may be Fe alone or a part of Fe may be substituted with Co.
- the temperature characteristics can be improved without deteriorating the magnetic characteristics.
- the Co content is desirably suppressed to 20% by mass or less of the Fe content. This is because if a part of Fe is replaced with Co so that the Co content is larger than 20 mass% of the Fe content, the magnetic properties may be deteriorated. Moreover, it becomes expensive.
- a part of B can be replaced with carbon (C).
- C carbon
- the corrosion resistance can be improved by replacing part of B with C.
- the substitution amount of C is an amount that does not substantially affect the magnetic characteristics.
- the rare earth sintered magnet according to the present embodiment contains elements such as Al, Bi, Sb, Ge, Sn, Si, Ga, and Zr from the viewpoint of improving coercive force and reducing manufacturing costs. Further, it may be included. These contents are also preferably in a range that does not affect the magnetic properties, and each content is preferably 5% by mass or less. In addition, oxygen (O), nitrogen (N), C, Ca, etc. are conceivable as components that are inevitably mixed. Each of these may be contained in an amount of about 0.5% by mass or less.
- the rare earth element content in the rare earth sintered magnet is 25% by mass to 35% by mass, preferably 28% by mass to 33% by mass, and the B content is 0.5% by mass to 1.5% by mass. Or less, preferably 0.8% by mass or more and 1.2% by mass or less.
- the Co content is preferably in the range of 4% by mass or less, more preferably 0.1% by mass or more and 2% by mass or less. More preferably, the content is 3% by mass or more and 1.5% by mass or less.
- Either one or both of Al and Cu can be contained in the range of 0.02% by mass to 0.6% by mass. By containing one or two of Al and Cu in this range, it is possible to increase the coercive force, increase the corrosion resistance, and improve the temperature characteristics of the obtained magnet.
- the Al content is preferably 0.03% by mass or more and 0.4% by mass or less, and more preferably 0.05% by mass or more and 0.25% by mass or less.
- the Cu content is preferably 0.3% by mass or less (provided that 0 is not included), more preferably 0.2% by mass or less (provided that 0 is not included), and 0.03% by mass. More preferably, the content is 0.15% by mass or less.
- the oxygen content is preferably 6000 ppm or less, more preferably 3000 ppm or less, and particularly preferably 2000 ppm or less.
- the carbon content is preferably 2000 ppm or less, more preferably 1500 ppm or less, and particularly preferably 1200 ppm or less.
- the nitrogen content is preferably 1000 ppm or less, more preferably 800 ppm or less, and particularly preferably 600 ppm or less.
- a rare earth element R2 (R2 is a rare earth element containing one or both of Dy and Tb) or a rare earth compound thereof is preferably used.
- R2 rare earth compounds include R2 hydride, R2 oxide, R2 fluoride, R2T alloy (T represents one or more transition metal elements including Fe or Fe and Co), R2T hydride, R2T oxide, Examples include R2TB alloy, R2TB hydride, and R2TB oxide.
- the slurry preferably contains a resin. Thereby, the adhesiveness to the rare earth sintered magnet body of the rare earth compound of R2 can be raised.
- the resin to be used is not particularly limited, and polyurethane resin, polyester resin, butyral resin, acrylic resin, phenol resin, epoxy resin, cellulose resin and the like are used.
- the solvent used for dissolving the resin is not particularly limited as long as it can dissolve the resin.
- the rare earth sintered magnet body is formed into an arbitrary shape by, for example, press molding.
- the shape of the rare earth sintered magnet body is not particularly limited, and may be any shape such as a flat plate shape, a columnar shape, or a cylindrical shape in which the sectional shape of the rare earth sintered magnet body is a C shape, depending on the shape of the mold used. It can be.
- the plane with the largest planar area is perpendicular to the orientation direction of the rare earth sintered magnet body
- the plane with the largest planar area is the residual magnetic flux.
- the surface in which the variation in density Br is the smallest among the surfaces of the rare earth sintered magnet body. Since the surface having the largest planar area becomes a surface perpendicular to the orientation direction of the rare earth sintered magnet body, variation in magnetic flux can be reduced.
- the shape of the rare earth sintered magnet body is a quadrangular prism
- the pair of side surfaces of the rare earth sintered magnet body is a plane perpendicular to the orientation direction of the rare earth sintered magnet body
- the side surface is a surface where the variation in the residual magnetic flux density Br is the smallest among the other surfaces of the rare earth sintered magnet body. Since the pair of side surfaces of the rare earth sintered magnet body is a plane perpendicular to the orientation direction of the rare earth sintered magnet body, variation in magnetic flux can be reduced.
- FIG. 1 is a flowchart showing a method for manufacturing a rare earth sintered magnet according to an embodiment of the present invention. As shown in FIG. 1, the manufacturing method of the rare earth sintered magnet according to the present embodiment includes the following steps.
- step S11 Rotating step of rotating the rare earth sintered magnet (step S12)
- step S13 Application step of applying slurry containing R2 rare earth compound to the rare earth sintered magnet
- step S14 A drying step of rotating the rare earth sintered magnet body that has been applied with the slurry and started rotating (step S14).
- Rotation stopping step step S15) for stopping the rotation of the rare earth sintered magnet body
- Heat treatment step step S16 of heat treating the rare earth sintered magnet body from which the slurry has been dried.
- FIG. 2 is a diagram schematically illustrating the configuration of the magnet manufacturing apparatus.
- the magnet manufacturing apparatus 10 includes a sintered body preparation mechanism 11, a coating mechanism 12, a drying mechanism 13, a heat treatment mechanism 14, a transport mechanism 15, and a control mechanism 16.
- the control mechanism 16 is a mechanism that controls the operation of each unit.
- manufacture of the rare earth sintered magnet which concerns on this embodiment is not limited to the case where the magnet manufacturing apparatus 10 is used. Any device that can apply slurry while rotating the rare earth sintered magnet body may be used.
- the rare earth sintered magnet according to the present embodiment is manufactured using the magnet manufacturing apparatus 10 shown in FIG. 2 will be described.
- Step S11> The magnet body preparation step (step S11) is a step of preparing a rare earth sintered magnet body used for manufacturing a rare earth sintered magnet in the sintered body preparation mechanism 11.
- FIG. 3 is a flowchart showing a method of manufacturing a rare earth sintered magnet body used for manufacturing the rare earth sintered magnet according to the embodiment of the present invention. As shown in FIG. 3, the method for manufacturing a rare earth sintered magnet body includes the following steps.
- Alloy preparation process for preparing an alloy (step S21) Coarse pulverization process to coarsely pulverize the alloy into a powder (step S22) Fine pulverization step for further finely pulverizing the coarsely pulverized powder (step S23) Molding process for molding finely pulverized raw material powder (step S24) Firing step (step S25) in which the molded body is heated and fired.
- Surface treatment process for treating the surface of the sintered body step S26
- the alloy preparation step (step S21) is a step of preparing an alloy from which a rare earth magnet body having a desired composition can be obtained.
- a simple substance, an alloy, a compound, or the like containing an element such as a metal corresponding to the composition of the rare earth magnet is dissolved in an inert gas atmosphere such as vacuum or argon, and then used.
- an alloy having a desired composition is produced by manufacturing the alloy using a casting method, a strip casting method, or the like.
- the alloy two kinds of alloys, that is, an alloy having a composition constituting the main phase in the rare earth magnet (main phase alloy) and an alloy having a composition constituting the grain boundary phase (grain boundary phase alloy) may be used.
- the process proceeds to the coarse pulverization step (step S22).
- the pulverization step (step S22) is a step of roughly pulverizing the alloy to obtain a powder.
- the obtained alloy is coarsely pulverized to obtain a powder having a particle size of about several hundred ⁇ m.
- the coarse pulverization of the alloy is performed by using a coarse pulverizer such as a jaw crusher, a brown mill, a stamp mill, or the like, or after the alloy has occluded hydrogen, it is self-destructive based on the difference in hydrogen occlusion between different phases It can be performed by causing pulverization (hydrogen occlusion pulverization).
- the process proceeds to the fine pulverization step (step S23).
- the fine pulverization step (step S23) is a step of further finely pulverizing the powder obtained by the coarse pulverization.
- the coarsely pulverized powder is further finely pulverized, so that the raw material powder of a rare earth magnet body having a particle size of preferably 1 ⁇ m or more and 10 ⁇ m or less, more preferably 3 ⁇ m or more and 5 ⁇ m or less (hereinafter simply referred to as “powder”) To obtain “raw powder”.
- the fine pulverization is performed by further pulverizing the coarsely pulverized powder using a fine pulverizer such as a jet mill, a ball mill, a vibration mill, or a wet attritor while appropriately adjusting conditions such as the pulverization time.
- a fine pulverizer such as a jet mill, a ball mill, a vibration mill, or a wet attritor while appropriately adjusting conditions such as the pulverization time.
- the raw material powder may be prepared by this.
- step S24 After the coarsely pulverized powder is further finely pulverized, the process proceeds to the molding step (step S24).
- the forming step (step S24) is a step of forming the finely pulverized raw material powder into a desired shape.
- the forming is performed while applying a magnetic field to cause the raw material powder to have a predetermined orientation.
- the molding can be performed, for example, by press molding. Specifically, after the raw material powder is filled in the mold cavity, the filled powder is pressed so as to be sandwiched between the upper punch and the lower punch, whereby the raw material powder can be formed into an arbitrary shape. .
- the shape of the molded body obtained by molding is not particularly limited, and may be any shape depending on the shape of the rare earth magnet body desired, such as a flat plate shape, a column shape, or a ring shape, depending on the shape of the mold to be used. It can be. In the present embodiment, a flat molded body is used. Pressure during molding is preferably carried out in a 0.5 ton / cm 2 or more 1.4ton / cm 2 or less. The applied magnetic field is preferably 12 kOe or more and 20 kOe or less.
- the molding method in addition to the dry molding in which the raw material powder is molded as it is, wet molding in which a slurry in which the raw material powder is dispersed in a solvent such as oil can be molded. After the finely pulverized raw material powder is molded into a desired shape to obtain a molded body, the process proceeds to the firing step (step S25).
- the firing step (step S25) is a step of performing firing by performing a process of heating the molded body.
- the molded body is fired, for example, by performing a treatment of heating in a vacuum or in the presence of an inert gas at 1010 ° C. or higher and 1110 ° C. or lower and 2 hours or longer and 6 hours or shorter. .
- an inert gas at 1010 ° C. or higher and 1110 ° C. or lower and 2 hours or longer and 6 hours or shorter.
- the raw material powder undergoes liquid phase sintering, and a sintered body (sintered body of rare earth magnet body) in which the volume ratio of the main phase is improved is obtained.
- the process proceeds to the surface treatment step (step S26).
- the surface treatment step (step S26) is a step of treating the surface of the sintered body with an acid solution.
- the obtained sintered body is appropriately processed into a desired size and shape, and then the surface of the sintered body is treated with, for example, an acid solution.
- an acid solution used for the surface treatment of the sintered body a mixed solution of an aqueous solution such as nitric acid or hydrochloric acid and an alcohol is preferable.
- This surface treatment can be performed, for example, by immersing the sintered body in an acid solution or spraying the acid solution on the sintered body.
- surface treatment it is possible to remove dirt, oxide layer, and the like adhering to the sintered body to obtain a clean surface, and adhesion and diffusion of the R2 rare earth compound described later are advantageous.
- surface treatment may be performed while applying ultrasonic waves to the acid solution.
- the sintered body is subjected to surface treatment to obtain a rare earth sintered magnet body.
- the prepared rare earth sintered magnet body is formed into a predetermined shape by forming the raw material powder in the forming step (step S24), but may be further processed into an arbitrary shape.
- the rare earth sintered magnet body is formed into a predetermined shape by, for example, press forming, punching, cutting or the like.
- the shape of the formed body is a flat plate shape in the forming step (step S24). For this reason, this embodiment demonstrates as an example the case where a flat-plate rare earth sintered magnet body is used.
- the sintered body preparation mechanism 11 prepares a plurality of rare earth sintered magnet bodies 21 and holds the rare earth sintered magnet bodies 21.
- the magnet manufacturing apparatus 10 transports the rare earth sintered magnet body 21 prepared by the sintered body preparation mechanism 11 to the coating mechanism 12 by the transport mechanism 15.
- the transport mechanism 15 is a transport mechanism that transports the sintered body, and transports the rare earth sintered magnet body 21 prepared by the sintered body preparation mechanism 11 to the coating mechanism 12.
- Various means can be used as the transport mechanism 15, for example, a belt conveyor, a robot arm, or the like can be used.
- the magnet manufacturing apparatus 10 transfers the rare earth sintered magnet body 21 to the coating mechanism 12 by the transfer mechanism 15 and then proceeds to the rotation process (step S12).
- Step S12 is a process in which the magnet manufacturing apparatus 10 holds the rare earth sintered magnet body transported from the sintered body preparation mechanism 11 by the transport mechanism 15 and rotates it.
- FIG. 4 is a schematic diagram schematically showing the configuration of the coating mechanism.
- the coating mechanism 12 includes a coating unit 23 that applies the slurry 22 to the rare earth sintered magnet body 21, and a rotation holding that holds the rare earth sintered magnet body 21 and rotates the rare earth sintered magnet body 21.
- Means 24 The coating unit 23 is disposed on the lower side in the vertical direction of the spray head 25, the plurality of spray ports 26 provided on the lower surface of the spray head 25, and collects the slurry 22 discharged from the spray port 26.
- a slurry recovery unit 27 The applying unit 23 applies the slurry 22 to the rare earth sintered magnet body 21 in an application step (step S13) described later.
- the rotation holding means 24 includes a contact portion 28, a rotation portion 29, and an attachment / detachment portion 30.
- the rotation holding means 24 has a symmetrical shape with a symmetry plane perpendicular to the rotation axis as an axis, and two contact portions 28 are brought into contact with both ends of the rare earth sintered magnet body 21, respectively. It is a structure that sandwiches the body 21.
- the magnet manufacturing apparatus 10 holds the rare earth sintered magnet body 21 transported to the coating mechanism 12 by the transport mechanism 15 by the rotation holding means 24, and then sets the contact portion 28 by the rotating portion 29 of the rotation holding means 24 of the coating mechanism 12. The rotation of the rare earth sintered magnet body 21 is started.
- the two contact portions 28 are members that contact the rare earth sintered magnet body 21 and are held by the rotating portion 29 and the attaching / detaching portion 30.
- the two contact portions 28 are disposed so as to face each other, and the rare earth sintered magnet body 21 is disposed between the two contact portions 28.
- both ends of the rare earth sintered magnet body 21 (in the present embodiment, end portions in the longitudinal direction of the rare earth sintered magnet body 21) are in contact with the contact portion 28.
- the rotating unit 29 is provided corresponding to the contact unit 28 and is a drive mechanism that rotates the contact unit 28.
- the rotating part 29 rotates the contact part 28 about an axis parallel to the longitudinal direction of the rare earth sintered magnet body 21 as a rotation axis (in the R direction in the figure).
- a method for rotating the contact portion 28 by the rotating portion 29 is not particularly limited.
- the shaft that connects the contact portion 28 and the rotation motor are connected by a transmission belt (pulley), and the rotation of the rotation motor is transmitted to the contact portion 28 via the transmission belt, so that the contact portion 28 is There is a way to rotate.
- the contact portion 28 may be directly connected to a motor to rotate the contact portion 28.
- the detachable portion 30 supports the contact portion 28 in a rotatable manner, and can be moved in a direction parallel to the rotation axis (the direction of arrow A in the figure). By moving the contact portion 28 in a direction parallel to the rotation axis (in the direction of arrow A in the figure), the detachable portion 30 can be moved in a direction parallel to the rotation axis, and the distance between the two contact portions 28 can be adjusted. it can.
- the rare earth sintered magnet body 21 can be attached and detached by increasing the distance between the two contact portions 28 and making it longer than the length of the rare earth sintered magnet body 21 in the longitudinal direction.
- the attaching / detaching portion 30 can also move while holding the rare earth sintered magnet body 21.
- the rotation holding means 24 moves the contact portion 28 in the direction parallel to the rotation axis by the attaching / detaching portion 30, so that the rare earth sintered magnet body 21 is attached / detached and the contact portion 28 is rotated by the rotating portion 29.
- the rare earth sintered magnet body 21 is rotated around the rotation axis.
- the magnet manufacturing apparatus 10 rotates the rare earth sintered magnet body 21 by the rotation holding means 24, and then proceeds to the coating process (step S13).
- Step S13> In the coating process (step S13), a slurry containing a rare earth compound is applied to the rotating rare earth sintered magnet body 21.
- the coating unit 23 is disposed on the lower side in the vertical direction of the spray head 25, the plurality of spray ports 26 provided on the lower surface of the spray head 25, and collects the slurry 22 discharged from the spray port 26.
- a slurry recovery unit 27 The spray head 25 is a storage unit that temporarily stores the slurry 22 supplied from the slurry circulation unit 31 and compresses the slurry 22 to a predetermined pressure or more.
- the plurality of injection ports 26 are formed in a row on the lower surface of the spray head 25 and spray the slurry 22 supplied from the spray head 25 at a predetermined pressure or more in a mist form.
- the slurry collection unit 27 collects the slurry 22 that has been ejected from the ejection port 26 of the spray head 25 and has not adhered to the rare earth sintered magnet body 21.
- recovery part 27 is comprised with a saucer, and the side surface becomes an inclined surface, and becomes a structure which flows into the lower surface in which the collection
- the coating mechanism 12 When applying the slurry 22 to the rare earth sintered magnet body 21, as shown in FIG. 4, the coating mechanism 12 rotates the rare earth sintered magnet body 21 held by the rotation holding means 24 while rotating the spray head 25 and the slurry. It is moved between the collection unit 27.
- the coating mechanism 12 applies the slurry 22 by the coating unit 23 while rotating the rare earth sintered magnet body 21 held by the rotation holding unit 24.
- the application unit 23 can apply the slurry 22 to the rare earth sintered magnet body 21 on the lower side in the vertical direction of the injection port 26 by injecting the slurry 22 from the injection port 26.
- the substantially entire surface of the rare earth sintered magnet body 21 passes through the position where the slurry 22 reaches, and the slurry 22 discharged from the injection port 26 is applied. Further, the slurry 22 that has not been applied to the rare earth sintered magnet body 21, that is, does not adhere to the rare earth sintered magnet body 21, is collected by the slurry collecting unit 27 that is lower than the rare earth sintered magnet body 21 in the vertical direction.
- FIG. 5 is a schematic diagram simply showing the configuration of the coating means.
- the coating unit 23 includes a slurry circulation unit 31 that supplies the slurry 22 to the spray head 25 and collects and circulates the slurry 22 from the slurry collection unit 27.
- the slurry 22 received by the slurry recovery unit 27 is recovered to the slurry tank 33 from the pipe 32a.
- the slurry tank 33 is a tank that stores the slurry 22, and stores a certain amount of the slurry 22.
- the slurry tank 33 is connected to the spray head 25 via a pipe 32b, and the recovered slurry 22 is circulated and supplied to the spray head 25 again.
- the coating mechanism 12 has a concentration adjusting unit 34 that adjusts the concentration of the slurry 22 circulated in the slurry circulating unit 31.
- the concentration adjusting unit 34 includes a solvent tank 35 and a pump 36.
- the solvent tank 35 is a tank in which the solvent (solvent) constituting the slurry 22 is stored, and is connected to the slurry tank 33 via a pipe 37.
- the concentration adjusting unit 34 supplies the solvent stored in the solvent tank 35 to the slurry tank 33 by the pump 36 provided in the pipe 37, and maintains the density of the slurry 22 in the slurry tank 33 within a certain range.
- the ratio of the solvent (solvent) and the solute (rare earth compound) can be in a certain range, and the concentration of the slurry 22 can be in a certain range.
- the slurry 22 can be applied to the surface of the sintered body by spraying the slurry 22 from the plurality of injection ports 26 toward the rare earth sintered magnet body 21. Moreover, by setting it as the structure which only injects the slurry 22 like this embodiment, the slurry 22 can be moved toward a sintered compact with a simple structure.
- the slurry 22 can be prevented from being displaced depending on the position of the sintered body and can be uniformly applied. . That is, even if the slurry flow is gathered at the center of the opening, the slurry 22 can be appropriately discharged also to the end side on the row by providing a plurality of injection ports 26 and arranging them at a predetermined interval.
- the method of applying the slurry 22 to the sintered body is not limited to the method of applying the slurry 22 using a spray, and various means for applying the slurry 22 can be used.
- the rare earth sintered magnet body 21 may be immersed in a slurry tank 38 in which the slurry 22 is stored and rotated to apply the slurry 22 to the rare earth sintered magnet body 21.
- the slurry 22 is discharged (dropped) as a slurry flow from the nozzle 39 provided on the lower surface of the spray head 25 vertically downward (below), and the rare earth sintered magnet body 21 is rotated.
- the slurry 22 may be applied to the rare earth sintered magnet body 21.
- by providing a plurality of nozzles 39 and further providing them on the line it is possible to prevent the slurry 22 from being displaced according to the position of the sintered body, and to apply uniformly. That is, even if the slurry flow is gathered at the center of the opening, by providing a plurality of nozzles 39 and arranging them at a predetermined interval, the slurry 22 can be appropriately discharged also to the end side on the line.
- the structure in which the slurry 22 is discharged from the nozzle 39 downward in the vertical direction simplifies the control and simplifies the structure.
- the present invention is not limited to this, and the slurry 22 may be applied to the sintered body, and the slurry 22 may be discharged from the nozzle 39 in an oblique direction or a lateral direction.
- the thickness of the film applied to the rare earth sintered magnet body 21 can be adjusted by adjusting the concentration of the slurry 22. That is, the film thickness can be increased by increasing the concentration of the slurry 22, and the film thickness can be decreased by decreasing the concentration of the slurry 22.
- the concentration adjusting unit 34 preferably maintains the slurry 22 in the range of the reference value ⁇ 0.050 g / cc, that is, the density of the slurry 22 is in the range of 0.100 g / cc, and is ⁇ 0.035 g / cc. More preferably, the density of the slurry 22 is in the range of 0.070 g / cc.
- concentration of the slurry 22 should just be more than the density
- the concentration of the slurry 22 is preferably 70 wt% or less, and more preferably 60 wt% or less. By setting the concentration of the slurry 22 to 70 wt% or less, the slurry 22 can be appropriately moved on the sintered body, and by rotating, the thickness of the slurry 22 can be made uniform.
- the magnet manufacturing apparatus 10 applies the slurry 22 to the rare earth sintered magnet body 21 by the application mechanism 12, and then proceeds to the drying step (step S14).
- the drying step (step S14) is a step of drying the slurry 22 attached (applied) to the rare earth sintered magnet body 21.
- the transport mechanism 15 transports the rare earth sintered magnet body 21 from the coating mechanism 12 to the drying mechanism 13.
- the rotation holding means 24 moves the rare earth sintered magnet body 21 to the drying mechanism 13 while rotating.
- the drying mechanism 13 volatilizes the solvent contained in the slurry 22 applied to the sintered body by the coating mechanism 12 while rotating the rare earth sintered magnet body 21 held by the rotation holding means 24, and the slurry 22 is applied.
- the sintered body is dried while rotating.
- the drying mechanism 13 can use various drying methods, for example, a method of drying by heating and blowing.
- the rare earth sintered magnet body 21 to which the slurry 22 is applied may be dried by natural drying.
- the magnet manufacturing apparatus 10 moves to the rotation stopping step (step S15) after drying the slurry 22 attached to the rare earth sintered magnet body 21.
- Step S15> The rotation stopping step (step S15) is a step of stopping the rotation of the rotating part 29 of the rotation holding means 24 and stopping the rotation of the rare earth sintered magnet body 21.
- the magnet manufacturing apparatus 10 collects the rare earth sintered magnet body 21 held by the rotation holding means 24 by the transport mechanism 15 and then proceeds to the heat treatment step (step S16).
- Step S16> the rare earth sintered magnet body 21 is heat treated. This is a step of diffusing the R2 rare earth compound contained in the slurry 22 adhering to the surface by heat treatment.
- the heat treatment mechanism 14 is a mechanism that heat-treats the rare earth sintered magnet body 21 in which the slurry 22 is dried by the drying mechanism 13.
- the heat treatment mechanism 14 heats the conveyed rare earth sintered magnet body 21 at a predetermined temperature for a predetermined time.
- the magnet manufacturing apparatus 10 performs a heat treatment, diffuses the R2 rare earth compound in the rare earth sintered magnet body 21, thereby manufacturing a rare earth sintered magnet and ends the process.
- the heat treatment is performed under reduced pressure as a vacuum or an inert gas atmosphere.
- Ar, He, or the like is used as the inert gas.
- the heat treatment temperature is set to a temperature equal to or lower than the sintering temperature of the rare earth sintered magnet body 21. This is because if the heat treatment is performed at a temperature equal to or higher than the sintering temperature of the rare earth sintered magnet body 21, the structure of the rare earth sintered magnet may be altered.
- the R2 rare earth compound diffuses not only to the crystal grain boundaries of the rare earth sintered magnet body 21 but also to the inside of the crystal grains, which may reduce the residual magnetic flux density Br on the surface of the rare earth sintered magnet body 21. is there.
- the heat treatment temperature is specifically 600 ° C. or higher and 1000 ° C. or lower, preferably 800 ° C. or higher and 950 ° C. or lower.
- An aging treatment can be performed after the heat treatment. Coercivity is improved by applying an aging treatment.
- the aging treatment temperature is 400 ° C. or higher and 650 ° C. or lower, more preferably 450 ° C. or higher and 600 ° C. or lower.
- the magnet manufacturing apparatus 10 applies the slurry 22 while rotating the rare earth sintered magnet body 21 and continuously rotates the rare earth sintered magnet body 21 by rotating the rare earth sintered magnet body 21 until the drying is completed. be able to.
- the magnet manufacturing apparatus 10 suppresses variations in the coercive force HcJ, the residual magnetic flux density Br, and the like on the surface of the rare earth sintered magnet body 21 by heat-treating the rare earth sintered magnet body 21 to which the slurry 22 is uniformly applied. it can.
- the performance as a magnet can be increased. For example, when used as a magnet of a motor, Cogging or the like can be made difficult to occur.
- the slurry 22 in which the R2 rare earth compound is dissolved is applied to the rare earth sintered magnet body 21 as in the present embodiment, and the R2 rare earth compound is adhered to the rare earth sintered magnet body 21, so that the R2 rare earth compound is adhered. Since it can suppress that a compound adheres except the surface of the rare earth sintered magnet body 21, the rare earth compound of R2 can be utilized efficiently. In the method in which the R2 rare earth compound is deposited by vapor deposition, the rare earth compound is also deposited in a region other than the rare earth sintered magnet body 21.
- the slurry 22 containing the R2 rare earth compound can be sprayed from the injection port 26 while rotating the rare earth sintered magnet body 21 by the coating means 23 and applied to the rare earth sintered magnet body 21.
- the rare earth compound of R2 can be used efficiently.
- the slurry 22 is collected, circulated, and reused, so that the R2 rare earth compound can be used without waste.
- the contact portion 28 is in contact with only both ends of the rare earth sintered magnet body 21, so that the slurry 22 is applied to the entire surface other than the portion in contact with the contact portion 28 of the rare earth sintered magnet body 21. Can be applied. For this reason, the part by which the slurry 22 of the rare earth sintered magnet body 21 is not apply
- the two contact portions 28 are in contact with both ends of the rare earth sintered magnet body 21 and sandwiched therebetween, but the present invention is not limited to this. For example, only one end portion of the rare earth sintered magnet body 21 may be held by the contact portion 28.
- the rotation of the rare earth sintered magnet body 21 is started, and the application of the slurry 22 is started while rotating the rare earth sintered magnet body 21, whereby the slurry 22 is formed on the rare earth sintered magnet body 21. It can suppress that it accumulates more than necessary, and can suppress that slurry 22 scatters. Moreover, since application
- the rotation of the rare earth sintered magnet body 21 is started before the slurry 22 is applied to the rare earth sintered magnet body 21, but the present invention is not limited to this.
- the application mechanism 12 may apply the slurry 22 and then rotate the rare earth sintered magnet body 21 to make the thickness of the slurry 22 attached to the surface of the rare earth sintered magnet body 21 uniform.
- a method for attaching the rare earth compound of R2 to the rare earth sintered magnet body 21 a plating method, a vapor deposition method, and the like can be given.
- the plating method a so-called dogbone phenomenon occurs in which the plating film thickness at the corners of the rare earth sintered magnet body 21 is several times (for example, 2 to 3 times) the other surface of the rare earth sintered magnet body 21.
- a film formed of the R2 rare earth compound cannot be obtained uniformly.
- the thickness of the film containing the R2 rare earth compound formed on the surface of the rare earth sintered magnet body 21 depending on the distance between the rare earth sintered magnet body 21 and the bulk body containing the R2 rare earth compound is: to be influenced. Therefore, it is difficult to obtain a magnet having a stable film thickness, and it is difficult to obtain a magnet having stable characteristics.
- jigs used for vapor deposition are distorted, so it is more difficult to maintain a uniform distance between the rare earth sintered magnet body 21 and the bulk body containing the R2 rare earth compound.
- the slurry 22 is applied to the surface of the rare earth sintered magnet body 21 while rotating the rare earth sintered magnet body 21, the slurry 22 is applied to the surface of the rare earth sintered magnet body 21.
- the slurry 22 is applied to the surface of the rare earth sintered magnet body 21.
- the rare earth sintered magnet can be obtained by applying the slurry 22 to the surface of the rare earth sintered magnet body 21 and drying it as in the present embodiment. Moreover, a magnet product is obtained by magnetizing. Further, the rare earth sintered magnet may be subjected to a surface treatment such as Ni plating on the surface of the rare earth sintered magnet to improve the corrosion resistance.
- This rare earth sintered magnet is suitably used as a magnet of a surface magnet type (Surface Permanent Magnet: SPM) motor, an IPM (Interior Permanent Magnet) motor, a PRM (Permanent magnet Reluctance Motor), etc. with a magnet attached to the rotor surface. .
- the SPM motor has advantages such as easy increase of the gap magnetic flux density and low noise generation.
- the spindle motor and voice coil motor for hard disk drive of a hard disk drive the motor for electric power steering of an automobile, and the servo of a machine tool. It is suitably used for applications such as motors, vibrators for mobile phones, and motors for printers.
- FIG. 8 is a longitudinal sectional view schematically showing a configuration of an embodiment of the SPM motor
- FIG. 9 is a diagram simply showing a section in the AA direction in FIG.
- the motor 40 includes a cylindrical stator 42, a columnar rotor 43, and a rotation shaft 44 in a housing 41.
- the rotating shaft 44 passes through the center of the cross section of the rotor 43.
- the stator 42 has a plurality of slots 45 at predetermined intervals in the circumferential direction inside the cylindrical wall (circumferential wall).
- a coil 45 a is wound around the slot 45.
- the rotor 43 includes a columnar rotor core 46 (iron core) made of iron or the like, and a plurality of permanent magnets 47 provided on the outer peripheral surface of the rotor core 46 at a predetermined interval.
- the rotor 43 is provided so as to be rotatable in a space in the stator 42 together with the rotation shaft 44.
- the permanent magnet 47 the rare earth sintered magnet according to the present embodiment is used.
- the motor 40 can suppress variations in coercive force HcJ, residual magnetic flux density Br, and the like on the surface of the permanent magnet 47. For this reason, it can suppress that a demagnetization arises by the demagnetizing field which the coil 45a produces during rotation of the motor 40.
- the motor 40 can reduce generation
- a rare earth sintered magnet body (sintered magnet) 21 was manufactured by the following method. First, a main phase alloy mainly forming a main phase of a magnet and a grain boundary alloy mainly forming a grain boundary were cast by a strip cast (SC) method. The composition of the main phase alloy is 23.0 wt% Nd-2.6 wt% Dy-5.9 wt% Pr-0.5 wt% Co-0.18 wt% Al-1.1 wt% B-bal. The composition of the grain boundary system alloy is 30.0 wt% Dy-0.18 wt% Al-0.6 wt% Cu-bal. Fe.
- SC strip cast
- each of these raw material alloys was roughly pulverized by hydrogen pulverization, and then subjected to jet mill pulverization with high-pressure N 2 gas to obtain fine powders each having an average particle diameter D of 4 ⁇ m.
- a magnetic powder was prepared.
- molding was performed in a magnetic field under conditions of a molding pressure of 1.2 t / cm 2 and an orientation magnetic field of 15 kOe to obtain a molded body.
- the molded body has a flat plate shape, and the flat plate surface is perpendicular to the orientation direction.
- the obtained molded body was fired at 1060 ° C. for 4 hours to produce a rare earth sintered magnet body 21 of a rare earth sintered magnet having the above composition. Thereafter, the manufactured rare earth sintered magnet body 21 is immersed in a mixed solution of 3 wt% HNO 3 / C 2 H 5 OH for 3 minutes, and then washed with C 2 H 5 OH twice. The surface treatment of the magnet body 21 was performed. In addition, these treatments were performed while applying ultrasonic waves.
- the slurry 22 adhered to the rare earth sintered magnet body 21 was manufactured as follows. First, 5 parts by mass of butyral resin (trade name: BM-S, manufactured by Sekisui Chemical Co., Ltd.) was dissolved in 550 parts by mass of isopropyl alcohol to prepare a resin solution. Next, 445 parts by mass of this resin solution and Dy hydride (DyH 2 ) (average particle diameter D: 5 ⁇ m) were put into a ball mill, and dispersed with 3 mm zirconia balls in an Ar atmosphere for 10 hours to produce a slurry. The Dy hydride used was prepared by occluding Dy powder at 350 ° C.
- DyH 2 obtained in this way is subjected to X-ray diffraction measurement, by analogy with the ERH 2 of JCPDS card (old ASTM card) 47-978, it can be identified as DyH 2.
- the slurry 22 produced as described above was put into the slurry tank 33 of the coating mechanism 12 and circulated at a flow rate of 500 cc / min.
- the concentration adjusting unit 34 causes the density of the slurry 22 to be in the range of 1.258 (g / cc) to 1.263 (g / cc). It was adjusted.
- the pump 36 was driven according to the measurement result, and the solvent was put into the slurry tank 33 from the solvent tank 35. Next, in a state where the rare earth sintered magnet body 21 was held by the rotation holding means 24, the rotating part 29 was rotated at a rotation speed of 20 rpm.
- the slurry 22 is sprayed by spraying from the injection port 26 for 5 seconds to apply the slurry 22, and then the rare earth sintered magnet body 21 is rotated. Drying was performed as it was. As a result, a slurry layer containing DyH 2 was formed on the surface of the rare earth sintered magnet body 21.
- the slurry 22 was applied so that the thickness of the slurry layer was about 20 ⁇ m. By setting the thickness of the slurry layer to about 20 ⁇ m, DyH 2 can be attached to the surface of the rare earth sintered magnet body 21 at a rate of 5.0 mg / cm 2 .
- the rare earth sintered magnet body 21 after drying was subjected to a heat treatment at 900 ° C. for 5 hours, and further subjected to an aging treatment at 540 ° C. for 1 hour to produce a rare earth sintered magnet.
- the size of the obtained rare earth sintered magnet was 2 mm (thickness: magnetic anisotropy direction) ⁇ 45 mm ⁇ 30 mm.
- Example 2 was performed using a method of applying the slurry 22 to the rare earth sintered magnet body 21 by immersing the rare earth sintered magnet body 21 in the slurry tank 38 as shown in FIG.
- the rare earth sintered magnet body 21 was immersed in the slurry tank 38 for 5 seconds and then rotated at 20 rpm by the rotating unit 29 under the same conditions as in Example 1.
- a rare earth sintered magnet was produced.
- Example 3 is performed using a method of applying the slurry 22 to the rare earth sintered magnet body 21 by discharging the slurry 22 as a slurry flow to the rare earth sintered magnet body 21 as shown in FIG. It was.
- the slurry 22 is discharged (dropped) as a slurry flow from the nozzle 39 provided on the lower surface of the spray head 25 in the vertical direction (below), and the rare earth sintered magnet body 21 is rotated.
- a rare earth sintered magnet was manufactured under the same conditions as in Example 1, except that the slurry 22 was applied to the rare earth sintered magnet body 21.
- Example 3 the slurry 22 produced as described above was put into the slurry tank 33 of the coating mechanism 12 and circulated at a flow rate of 500 cc / min.
- the density adjusting unit 34 adjusted the density of the slurry 22 to be in the range of 1.258 (g / cc) to 1.263 (g / cc).
- the pump 36 was driven according to the density of the slurry 22, and the solvent was charged from the solvent tank 35 to the slurry tank 33.
- the rare earth sintered magnet body 21 was rotated at a rotation speed of 20 rpm while being held by the rotation holding means 24.
- the slurry 22 was applied to the rotating rare earth sintered magnet body 21 from the nozzle 39 for 5 seconds, and then the rare earth sintered magnet body 21 was dried while being rotated.
- Example 4 In Example 4, a rare earth sintered magnet was produced under the same conditions as in Example 1 except that the rotation speed was 10 rpm in Example 3.
- Example 5 In Example 5, a rare earth sintered magnet was produced under the same conditions as in Example 1 except that the rotation speed was 30 rpm in Example 3, and the characteristics were measured in the same manner.
- Example 6 a rare earth sintered magnet was produced under the same conditions as in Example 1 except that the supply position of the slurry 22 was changed to the side surface in Example 3.
- Example 7 a rare earth sintered magnet was produced under the same conditions as in Example 1 except that the rotation speed was changed to 60 rpm in Example 3.
- Example 8 In Example 8, a rare earth sintered magnet was produced under the same conditions as in Example 1 except that the rotation speed was changed to 1 rpm in Example 3.
- Comparative Example 1 a rare earth sintered magnet was produced by applying and drying the slurry 22 without rotating the rare earth sintered magnet body 21.
- the slurry 22 produced in Example 1 was put into a slurry tank 38 (see FIG. 6), immersed for 10 seconds while applying ultrasonic waves, then pulled up and dried.
- a rare earth sintered magnet was produced under the same conditions as in Example 1 except that DyH 2 was adhered to the surface of the rare earth sintered magnet body 21.
- FIG. 10 is a view showing an example of a processing vessel used for vapor-depositing DyH 2 on the surface of the rare earth sintered magnet body 21.
- the processing chamber 51 is made of a refractory metal material such as Mo, and a pair of support bases 53 that support the net 52 are provided inside the processing chamber 51.
- the sintered magnet body 21 (two in FIG. 10) and the RH bulk body 54 (two in FIG. 10) are installed in the net 52, and the rare earth sintered magnet body 21 and the RH bulk body are disposed in the processing chamber 51. 54 was placed facing each other with an interval of about 5 mm to 9 mm.
- the RH bulk body 54 is made of Dy having a purity of 99.9% and has a length of 30 mm ⁇ width of 30 mm ⁇ height of 5 mm.
- the processing container of FIG. 10 was heated in a vacuum heat treatment furnace to perform heat treatment.
- the heat treatment was performed at a heat treatment temperature of 900 ° C. for 180 minutes and a pressure of 1.0 ⁇ 10 ⁇ 2 Pa.
- the heat treatment temperature refers to the temperature of the sintered magnet body and the RH bulk body.
- an aging treatment was performed at 500 ° C. for 60 minutes at a pressure of 2 Pa.
- DyH 2 evaporated from the RH bulk body 52 was deposited on the surface of the sintered magnet body 21 and diffused inside the sintered magnet body 21.
- a rare earth sintered magnet having DyH 2 deposited and diffused on the surface of the rare earth sintered magnet body 21 was produced.
- the characteristics of the manufactured rare earth sintered magnet were measured by the following method. As characteristics, the amount of DyH 2 applied (the amount of adhesion) applied to the surface of the rare earth sintered magnet body 21 of the rare earth sintered magnet and the magnetic characteristics were measured. For the magnetic characteristics, a coercivity improvement width by application ( ⁇ HcJ) and a residual magnetic flux density decrease width by application ( ⁇ Br) were measured. Magnetic field analysis simulation was performed using the rare earth sintered magnet body 21 and the rare earth sintered magnet coated with DyH 2 by the slurry coating method of Examples 1, 8 and Comparative Example 1, and the rare earth sintered magnet was demagnetized. The demagnetization temperature and the cogging torque were measured.
- the rare earth sintered magnet body 21 has a flat plate shape as described above.
- the amount of DyH 2 applied to each rare earth sintered magnet body 21 is 9 on the surface having the largest area of the rare earth sintered magnet body 21 from the first region to the ninth region as shown in FIG.
- the film thickness was divided and the film thickness in the vicinity of the center of the coated surface of each region was measured using a micrometer. Since the rare earth sintered magnet body 21 has a flat plate shape, the direction parallel to the rotation axis is the longitudinal direction of the surface, and the direction perpendicular to the rotation axis is the short direction of the surface.
- the first to third regions of the nine divided regions as described above are regions that are vertically upward during immersion, and the seventh to ninth regions are immersed. It is a region that is sometimes vertically downward.
- Tables 1 and 2 show the measurement results of the rare earth sintered magnets coated with DyH 2 by the slurry coating methods of Examples 1 to 8 and Comparative Example 1 described above.
- Table 1 shows the measured DyH 2 coating amount, film thickness, average value, and difference R between the maximum and minimum values.
- Table 2 shows the coercivity improvement width ( ⁇ HcJ) by coating and the residual magnetic flux density decrease width ( ⁇ Br) by coating.
- the slurry 22 can be applied more uniformly by rotating the rare-earth sintered magnet body 21 (Example 1 to Example 8) rather than not rotating (Comparative Example 1). Moreover, it turns out that it can be set as a suitable film thickness by making a rotational speed appropriate (Example 1 to Example 6). Specifically, it can be seen that if the rotational speed is too fast (Example 7), the film thickness becomes thin, and if the rotational speed is too slow (Example 8), the film thickness becomes thick.
- the rare earth sintered magnet obtained by rotating (Example 1 to Example 8) rather than not rotating the rare earth sintered magnet body 21 (Comparative Example 1) has a coercive force HcJ on its surface, It can be seen that the variation in the residual magnetic flux density Br is reduced, and the coercive force HcJ and the residual magnetic flux density Br can be made more uniform. If the rotational speed is too slow (Example 8), the obtained rare earth sintered magnet has a large variation in coercive force HcJ and residual magnetic flux density Br on its surface, and the rotational speed is made appropriate (from Example 1). In Example 7), it can be seen that the obtained rare earth sintered magnet can have an appropriate coercive force HcJ and residual magnetic flux density Br. Therefore, the rare earth sintered magnet obtained by applying the slurry while rotating the rare earth sintered magnet body at an appropriate rotation speed can suppress variations in coercive force HcJ and residual magnetic flux density Br on the surface.
- the rare earth sintered magnet obtained by vapor-diffusion diffusion of DyH 2 at a high temperature and high vacuum degree on the surface of the rare earth sintered magnet body 21 can sufficiently suppress variations in coercive force HcJ and residual magnetic flux density Br on the surface.
- FIG. 12 is a cross-sectional view schematically showing an example of the configuration of the motor used in the magnetic field analysis simulation.
- the motor 60 includes a permanent magnet 61 made of a rare earth sintered magnet used in the base material, Examples 1 and 8 and Comparative Example 1 inside the rotor core 46.
- a magnetic field analysis was performed by applying a magnetic field.
- Table 3 shows the demagnetization temperature and cogging torque of the base material, and the demagnetization temperature and cogging torque of the rare earth sintered magnets used in Examples 1 and 8 and Comparative Example 1.
- Table 3 shows the demagnetization temperature and cogging torque of the base material, and the demagnetization temperature and cogging torque of the rare earth sintered magnets used in Examples 1 and 8 and Comparative Example 1.
- the amplitude of the rare earth sintered magnet body 21 before applying the slurry 22 was set to 1.
- Example 1 As shown in Table 3, by applying the slurry 22 while rotating the rare earth sintered magnet body 21 without rotating the rare earth sintered magnet body 21 (Comparative Example 1) (Examples 1 and 8), demagnetization is achieved. It can be seen that the temperature can be increased and the cogging torque can be reduced. Also, if the rotational speed is too slow (Example 8), the variation in coercive force HcJ, residual magnetic flux density Br, etc. will increase, the demagnetization temperature will decrease, and the cogging torque will increase. It can be seen that by making it appropriate (Example 1), the demagnetization temperature can be raised and the cogging torque can be reduced.
- the rare earth sintered magnet obtained by applying the slurry while rotating the rare earth sintered magnet body at an appropriate rotation speed increases the demagnetizing temperature and decreases the cogging torque, so it can be used as a permanent magnet for a motor.
- motor performance such as motor torque characteristics can be improved.
- the rare earth sintered magnet obtained by applying the slurry while rotating the rare earth sintered magnet body at an appropriate rotation speed can be suitably used as a permanent magnet for a motor.
Abstract
Description
<希土類焼結磁石>
本実施形態に係る希土類焼結磁石の実施形態について説明する。本実施形態に係る希土類焼結磁石は、(R1、R2)2T14B(R1はDy、Tbを除く少なくとも1種の希土類元素であり、R2はDy、Tbの何れか一方又は両方を少なくとも含む希土類元素であり、TはFe又はFe及びCoを含む1種以上の遷移金属元素を表す)の結晶粒を含む希土類焼結磁石体を有する希土類焼結磁石である。また、本実施形態に係る希土類焼結磁石は、希土類焼結磁石体中の結晶粒の周りを取り囲む結晶粒界に含まれるR1とR2との和に対するR2の割合が、結晶粒中のR1とR2との和に対するR2の割合より高く、R2の濃度が希土類焼結磁石体中心部から希土類焼結磁石体表面に向かって高くなるようにしている。
上述したような構成を有する希土類焼結磁石の好適な製造方法について図面を用いて説明する。図1は、本発明の実施形態に係る希土類焼結磁石の製造方法を示すフローチャートである。図1に示すように、本実施形態に係る希土類焼結磁石の製造方法は、以下の工程を含んでなる。
(R1、R2)2T14Bの結晶粒を含む希土類焼結磁石体を供給する磁石体準備工程(ステップS11)
前記希土類焼結磁石体を回転させる回転工程(ステップS12)
前記希土類焼結磁石体に、R2の希土類化合物を含むスラリーを塗布する塗布工程(ステップS13)
前記スラリーが塗布され、回転が開始された希土類焼結磁石体を回転させつつ、乾燥させる乾燥工程(ステップS14)
前記希土類焼結磁石体の回転を停止する回転停止工程(ステップS15)
前記スラリーが乾燥された希土類焼結磁石体を熱処理する熱処理工程(ステップS16)
磁石体準備工程(ステップS11)は、焼結体準備機構11において希土類焼結磁石を製造するために用いられる希土類焼結磁石体を準備する工程である。図3は、本発明の実施形態に係る希土類焼結磁石を製造するために用いられる希土類焼結磁石体の製造方法を示すフローチャートである。図3に示すように、希土類焼結磁石体の製造方法は、以下の工程を含んでなる。
合金を準備する合金準備工程(ステップS21)
合金を粗粉砕して粉末とする粗粉砕工程(ステップS22)
粗粉砕した粉末を更に微粉砕する微粉砕工程(ステップS23)
微粉砕した原料粉末を成形する成形工程(ステップS24)
成形体に加熱する処理を行い焼成を行う焼成工程(ステップS25)
焼結体の表面を処理する表面処理工程(ステップS26)
回転工程(ステップS12)は、磁石製造装置10は、搬送機構15によって焼結体準備機構11から搬送される希土類焼結磁石体を塗布機構12で保持し、回転させる工程である。図4は、塗布機構の構成を簡略に示す模式図である。図4に示すように、塗布機構12は、希土類焼結磁石体21にスラリー22を塗布する塗布手段23と、希土類焼結磁石体21を保持し、希土類焼結磁石体21を回転させる回転保持手段24とを有する。塗布手段23は、スプレーヘッド25と、スプレーヘッド25の下面に設けられた複数の噴射口26と、スプレーヘッド25の鉛直方向下側に配置され、噴射口26から放出されたスラリー22を回収するスラリー回収部27とを有する。塗布手段23は、後述する塗布工程(ステップS13)において希土類焼結磁石体21にスラリー22を塗布する。
塗布工程(ステップS13)では、回転している希土類焼結磁石体21に、希土類化合物を含むスラリーを塗布する。塗布手段23は、スプレーヘッド25と、スプレーヘッド25の下面に設けられた複数の噴射口26と、スプレーヘッド25の鉛直方向下側に配置され、噴射口26から放出されたスラリー22を回収するスラリー回収部27とを有する。スプレーヘッド25は、スラリー循環部31から供給されるスラリー22を一時的に貯留し、一定圧以上に圧縮する貯留部である。複数の噴射口26は、スプレーヘッド25の下面に列上に形成され、スプレーヘッド25から一定圧以上で供給されたスラリー22を霧状に噴射させる。スラリー回収部27は、スプレーヘッド25の噴射口26から噴射され、希土類焼結磁石体21に付着しなかったスラリー22を回収する。また、スラリー回収部27は、受け皿で構成され、側面が傾斜面となっており、側面に付着したスラリー22を回収する回収口が形成された下面に流れる構成となっている。
乾燥工程(ステップS14)は、希土類焼結磁石体21に付着した(塗布された)スラリー22を乾燥させる工程である。搬送機構15は、塗布機構12から乾燥機構13へ希土類焼結磁石体21を搬送する。このとき、回転保持手段24は、希土類焼結磁石体21を回転させたまま乾燥機構13に移動させる。乾燥機構13は、回転保持手段24により保持された希土類焼結磁石体21を回転させたまま塗布機構12で焼結体に塗布されたスラリー22に含まれる溶剤を揮発させ、スラリー22が塗布された焼結体を回転させつつ乾燥する。
回転停止工程(ステップS15)は、回転保持手段24の回転部29の駆動を停止し、希土類焼結磁石体21の回転を停止させる工程である。磁石製造装置10は、搬送機構15により回転保持手段24に保持されている希土類焼結磁石体21を回収した後、熱処理工程(ステップS16)に移行する。
熱処理工程(ステップS16)は、希土類焼結磁石体21に熱処理を施す。熱処理を施すことにより、表面に付着したスラリー22に含まれていたR2の希土類化合物を拡散させる工程である。熱処理機構14は、乾燥機構13でスラリー22が乾燥された希土類焼結磁石体21に熱処理を施す機構である。熱処理機構14は、搬送された希土類焼結磁石体21を所定の時間、所定の温度で加熱する。磁石製造装置10は、熱処理を施し、希土類焼結磁石体21にR2の希土類化合物を拡散させることで、希土類焼結磁石を製造し、処理を終了する。
本実施形態に係る希土類焼結磁石をモータに用いた好適な実施形態について説明する。ここでは、本実施形態に係る希土類焼結磁石をSPMモータに適用した一例について説明する。図8は、SPMモータの一実施形態の構成を簡略に示す縦断面図であり、図9は、図8中、A-A方向の断面を簡略に示す図である。図8、9に示すように、モータ40は、ハウジング41内に円筒状のステータ42と、円柱状のロータ43と、回転軸44とを有する。回転軸44はロータ43の横断面の中心を貫通している。ステータ42は、その筒壁(周壁)の内部の周方向に所定間隔で複数のスロット45を有する。そのスロット45にはコイル45aが巻きつけられている。ロータ43は、鉄材等からなる円柱状のロータコア46(鉄芯)と、そのロータコア46の外周面に所定間隔で設けられた複数の永久磁石47を有する。ロータ43は、回転軸44とともにステータ42内の空間内で回動可能に設けられている。永久磁石47には本実施形態に係る希土類焼結磁石が用いられる。
[実施例1]
(希土類焼結磁石体の製造)
以下に示す方法で希土類焼結磁石体(焼結体磁石)21を製造した。まず、主に磁石の主相を形成する主相系合金と、主に粒界を形成する粒界系合金を、ストリップキャスト(SC)法で鋳造した。主相系合金の組成は23.0wt%Nd-2.6wt%Dy-5.9wt%Pr-0.5wt%Co-0.18wt%Al-1.1wt%B-bal.Feで、粒界系合金の組成は30.0wt%Dy-0.18wt%Al-0.6wt%Cu-bal.Feであった。
次に、希土類焼結磁石体21に付着させるスラリー22は、以下のようにして製造した。まず、イソプロピルアルコール550質量部中にブチラール樹脂(商品名:BM-S、積水化学社製)5質量部を溶解し、樹脂溶液を作製した。次にこの樹脂溶液とDy水素化物(DyH2)(平均粒径D:5μm)445質量部をボールミルに投入し、Ar雰囲気下で3mmのジルコニアボールで10時間分散を行い、スラリーを製造した。なお、使用したDy水素化物は、Dy粉末を水素雰囲気下350℃で1時間吸蔵させ、これに続いてAr雰囲気下、600℃で1時間処理することにより作製したものである。このようにして得られたDyH2は、X線回折測定を行い、JCPDSカード(旧ASTMカード) 47-978のErH2からの類推により、DyH2であると同定することができる。
上記のようにして製造したスラリー22を塗布機構12のスラリータンク33に投入し、500cc/minの流量で循環させた。また、循環中の溶剤揮発による濃度変動を防ぐために、濃度調整部34により、スラリー22の密度が、1.258(g/cc)から1.263(g/cc)の範囲となるように、調整した。測定結果に応じてポンプ36を駆動し、溶剤タンク35からスラリータンク33に溶剤を投入した。次に、希土類焼結磁石体21を回転保持手段24により保持した状態で、回転部29により、回転速度20rpmで回転させた。この回転している希土類焼結磁石体21に対して、噴射口26から5秒間、スラリー22をスプレー方式で噴射し、スラリー22の塗布を行い、その後、希土類焼結磁石体21を回転させたまま乾燥を行なった。これにより希土類焼結磁石体21の表面にDyH2を含むスラリー層を形成した。なお、スラリー層の膜厚は20μm程度となるようにスラリー22を塗布した。スラリー層の膜厚を20μm程度とすることで、希土類焼結磁石体21の表面にDyH2を5.0mg/cm2の割合で付着させることができる。
実施例2は、塗布機構12の構成として図6に示すように希土類焼結磁石体21をスラリー槽38に浸漬して希土類焼結磁石体21にスラリー22を塗布する方法を用いて行った。実施例2は、図6に示すように希土類焼結磁石体21をスラリー槽38に5秒浸漬し、その後、回転部29により20rpmで、回転させたこと以外は実施例1と同様の条件で希土類焼結磁石を製造した。
実施例3は、塗布機構12の構成として図7に示すように希土類焼結磁石体21にスラリー22をスラリー流として放出して希土類焼結磁石体21にスラリー22を塗布する方法を用いて行った。実施例3は、図7に示すようにスプレーヘッド25の下面に設けたノズル39から鉛直方向下側(真下)にスラリー22をスラリー流として放出(落下)し、希土類焼結磁石体21を回転させながら希土類焼結磁石体21にスラリー22を塗布するようにしたこと以外は、実施例1と同様の条件で、希土類焼結磁石を製造した。
実施例4は、実施例3で回転速度を10rpmにした他は実施例1と同様の条件で希土類焼結磁石を作製した。
実施例5は、実施例3で回転速度を30rpmにした他は実施例1と同様の条件で希土類焼結磁石を作製し、同様に特性を計測した。
実施例6は、実施例3でスラリー22の供給位置を側面に変更した他は実施例1と同様の条件で希土類焼結磁石を作製した。
実施例7は、実施例3で回転速度を60rpmに変更した他は実施例1と同様の条件で希土類焼結磁石を作製した。
実施例8は、実施例3で回転速度を1rpmに変更した他は実施例1と同様の条件で希土類焼結磁石を作製した。
比較例1は、希土類焼結磁石体21を回転させることなくスラリー22の塗布及び乾燥を行って希土類焼結磁石を作製したものである。比較例1は、実施例1で作製したスラリー22をスラリー槽38(図6参照)に投入し、超音波を印加しながら10秒間浸漬した後、引き上げて乾燥した。これにより、希土類焼結磁石体21の表面にDyH2を付着させた他は実施例1と同様の条件で希土類焼結磁石を作製した。
比較例2は、希土類焼結磁石体21の表面にDyH2を高温高真空度で蒸着拡散させ、希土類焼結磁石を作製した。具体的には、希土類焼結磁石体21を0.3%硝酸水溶液で酸洗し、乾燥させた後、図10に示すような処理容器内に配置した。図10は、希土類焼結磁石体21の表面にDyH2を蒸着拡散させるために用いた処理容器の一例を示す図である。図10に示すように、処理室51はMoなど高融点金属材料から形成され、処理室51の内部には、網52を支持する一対の支持台53を設けた。網52に焼結磁石体21(図10中では、2つ)およびRHバルク体54(図10中では、2つ)を設置し、処理室51内で希土類焼結磁石体21とRHバルク体54とは5mm~9mm程度間隔を有した状態で対向配置させた。RHバルク体54は、純度99.9%のDyから形成され、縦30mm×幅30mm×高さ5mmのものを用いた。
製造した希土類焼結磁石の特性を以下の方法で測定した。なお、特性としては、希土類焼結磁石の希土類焼結磁石体21の表面に塗布したDyH2の塗布量(付着量)及び磁気特性を測定した。磁気特性は、塗布による保磁力向上幅(ΔHcJ)及び塗布による残留磁束密度低下幅(ΔBr)を測定した。また、希土類焼結磁石体21と、実施例1、8、比較例1のスラリーの塗布方法でDyH2を塗布した希土類焼結磁石を用いて磁場解析シミュレーションを行い、希土類焼結磁石が減磁し始める減磁温度とコギングトルクを測定した。
まず、希土類焼結磁石体21をDyH2のスラリー22を塗布する前の質量とスラリー22を塗布して乾燥させた後の質量とを測定し、これらを比較することによって、焼結体へのDyH2の塗布量を算出した。この結果から希土類焼結磁石体21の単位表面積あたりのDyH2の塗布量(mg/cm2)を算出した。
回転軸に直交する方向(面の短手方向)の一方の端で、回転軸に平行な方向(面の長手方向)の一方の端:第1領域
回転軸に平行な方向において第1領域の隣の領域:第2領域
回転軸に直交する方向の一方の端で、回転軸に平行な方向の他方の端:第3領域
回転軸に直交する方向において中央となる領域で、第1領域に隣接する領域:第4領域
回転軸に直交する方向において中央となる領域で、第2領域に隣接する領域:第5領域
回転軸に直交する方向において中央となる領域で、第3領域に隣接する領域:第6領域
回転軸に直交する方向の他方の端で、第4領域に隣接する領域:第7領域
回転軸に直交する方向の他方の端で、第5領域に隣接する領域:第8領域
回転軸に直交する方向の他方の端で、第6領域に隣接する領域:第9領域
磁気特性(ΔHcJ、ΔBr)の計測は、上記のように図11に示すように9つに分けた領域の第1領域から第9領域の各々の中心付近から1mm角の試料片を取り出した。取り出した各領域の試料片の一部はパルスBHトレーサーにより測定し、保磁力HcJを求めた。また、アクリル棒に固定し、振動試料型磁力計(VSM:Vibrating Sample Magnetometer)を用いて測定して残留磁束密度Brを測定した。この得られた結果から、保磁力向上幅ΔHcJ、塗布による残留磁束密度低下幅ΔBrを各々算出した。
次に、スラリー22を塗布する前の希土類焼結磁石体21(基材)、実施例1、8、比較例1に用いた希土類焼結磁石を用いて磁場解析シミュレーションを行い、減磁温度とコギングトルクを測定した。ここでは、図8、9に示すモータ40をSPMモータからIPMモータとして用い、スラリー22を塗布する前の希土類焼結磁石体21(基材)、実施例1、8、比較例1に用いた希土類焼結磁石をIPMモータ用の永久磁石として適用して磁場解析シミュレーションを行なった。図8、9に示すモータ40と同一の構成については同一符号を付して重複した説明は省略する。図12は、磁場解析シミュレーションに用いたモータの構成の一例を簡略に示す横断面図である。図12に示すように、モータ60は、ロータコア46の内部に、基材、実施例1、8、比較例1に用いた希土類焼結磁石を永久磁石61を有する。ロータコア46の内部に永久磁石61を配置した後、磁場を印加して磁場解析シミュレーションを行なった。基材の減磁温度及びコギングトルクと、実施例1、8、比較例1に用いた希土類焼結磁石の減磁温度及びコギングトルクとを表3に示す。なお、表3中、コギングトルクは、スラリー22を塗布する前の希土類焼結磁石体21の振幅を1とした。
11 焼結体準備機構
12 塗布機構
13 乾燥機構
14 熱処理機構
15 搬送機構
16 制御機構
21 希土類焼結磁石体
22 スラリー
23 塗布手段
24 回転保持手段
25 スプレーヘッド
26 噴射口
27 スラリー回収部
28 接触部
29 回転部
30 着脱部
31 スラリー循環部
32a、32b、37 配管
33 スラリータンク
34 濃度調整部
35 溶剤タンク
36 ポンプ
38 スラリー槽
39 ノズル
40 モータ
41 ハウジング
42 ステータ
43 ロータ
44 回転軸
45 スロット
45a コイル
46 ロータコア
47、61 永久磁石
Claims (9)
- (R1、R2)2T14B(R1はDy、Tbを除く少なくとも1種の希土類元素であり、R2はDy、Tbの何れか一方又は両方を少なくとも含む希土類元素であり、TはFe又はFe及びCoを含む1種以上の遷移金属元素を表す)の結晶粒を含む希土類焼結磁石体を有する希土類焼結磁石であり、
前記希土類焼結磁石体中の前記結晶粒の周りを取り囲む結晶粒界に含まれるR1とR2との和に対するR2の割合が、前記結晶粒中のR1とR2との和に対するR2の割合より高く、R2の濃度が希土類焼結磁石体中心部から希土類焼結磁石体表面に向かって高くなると共に、
前記希土類焼結磁石体の表面における残留磁束密度のばらつきが3.0%未満であることを特徴とする希土類焼結磁石。 - 前記希土類焼結磁石体の表面における保磁力のばらつきが、18.0%未満であることを請求項1に記載の希土類焼結磁石。
- 前記希土類焼結磁石体が複数の面を有し、
前記希土類焼結磁石体の複数の面の中で前記残留磁束密度のばらつきが最小となる面が、前記希土類焼結磁石体の配向方向に対し垂直な面である請求項1又は2に記載の希土類焼結磁石。 - (R1、R2)2T14B(R1はDy、Tbを除く少なくとも1種の希土類元素であり、R2はDy、Tbの何れか一方又は両方を少なくとも含む希土類元素であり、TはFe又はFe及びCoを含む1種以上の遷移金属元素を表す)の結晶粒を含む希土類焼結磁石体を回転させ、
R2の希土類化合物を含むスラリーを前記希土類焼結磁石体に塗布し、
前記希土類焼結磁石体を回転させつつ、乾燥させ、
前記スラリーが乾燥された希土類焼結磁石体を熱処理することにより得られ、
前記希土類焼結磁石体中の前記結晶粒の周りを取り囲む結晶粒界に含まれるR1とR2との和に対するR2の割合が、前記結晶粒中のR1とR2との和に対するR2の割合より高く、R2の濃度が希土類焼結磁石体中心部から希土類焼結磁石体表面に向かって高くなると共に、
前記希土類焼結磁石体の表面における残留磁束密度のばらつきが3.0%未満であることを特徴とする希土類焼結磁石。 - 前記スラリーを、スプレーにより前記希土類焼結磁石体に吹き付け、前記希土類焼結磁石体に塗布する請求項4に記載の希土類焼結磁石。
- 前記希土類焼結磁石体を、前記スラリーが貯留された領域に浸漬させ、前記希土類焼結磁石体に前記スラリーを塗布する請求項4に記載の希土類焼結磁石。
- 前記スラリーは、複数のスラリー流として前記希土類焼結磁石体に塗布される請求項4に記載の希土類焼結磁石。
- 前記スラリーは、前記希土類焼結磁石体の配置位置の鉛直方向上方から落下させて前記希土類焼結磁石体に塗布される請求項4に記載の希土類焼結磁石。
- 周方向に配置された複数のコイルを有するステータと、
前記ステータ内に回動可能に設けられ、且つ、外周面に所定間隔で請求項1乃至8の何れか1つに記載の希土類焼結磁石が設けられるロータコアを備えるロータと、
を有することを特徴とするモータ。
Priority Applications (4)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US13/390,016 US9154004B2 (en) | 2010-03-04 | 2011-03-04 | Rare earth sintered magnet and motor |
JP2012503287A JP5472444B2 (ja) | 2010-03-04 | 2011-03-04 | 希土類焼結磁石及びモータ |
EP11750813.5A EP2544199A4 (en) | 2010-03-04 | 2011-03-04 | Sintered rare-earth magnet and motor |
CN201180003230.8A CN102483980B (zh) | 2010-03-04 | 2011-03-04 | 稀土烧结磁体和电动机 |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP2010-048287 | 2010-03-04 | ||
JP2010048287 | 2010-03-04 |
Publications (1)
Publication Number | Publication Date |
---|---|
WO2011108704A1 true WO2011108704A1 (ja) | 2011-09-09 |
Family
ID=44542348
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/JP2011/055067 WO2011108704A1 (ja) | 2010-03-04 | 2011-03-04 | 希土類焼結磁石及びモータ |
Country Status (5)
Country | Link |
---|---|
US (1) | US9154004B2 (ja) |
EP (1) | EP2544199A4 (ja) |
JP (1) | JP5472444B2 (ja) |
CN (1) | CN102483980B (ja) |
WO (1) | WO2011108704A1 (ja) |
Cited By (16)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2014063997A (ja) * | 2012-08-31 | 2014-04-10 | Shin Etsu Chem Co Ltd | 希土類永久磁石の製造方法 |
JP2014063996A (ja) * | 2012-08-31 | 2014-04-10 | Shin Etsu Chem Co Ltd | 希土類永久磁石の製造方法 |
JP2014063998A (ja) * | 2012-08-31 | 2014-04-10 | Shin Etsu Chem Co Ltd | 希土類永久磁石の製造方法 |
CN103890868A (zh) * | 2011-10-28 | 2014-06-25 | Tdk株式会社 | R-t-b系烧结磁铁 |
JP2015065218A (ja) * | 2013-09-24 | 2015-04-09 | 大同特殊鋼株式会社 | RFeB系磁石の製造方法 |
JP2015154051A (ja) * | 2014-02-19 | 2015-08-24 | 信越化学工業株式会社 | 希土類永久磁石の製造方法 |
WO2016175061A1 (ja) * | 2015-04-28 | 2016-11-03 | 信越化学工業株式会社 | 希土類磁石の製造方法及び希土類化合物の塗布装置 |
WO2016175059A1 (ja) * | 2015-04-28 | 2016-11-03 | 信越化学工業株式会社 | 希土類磁石の製造方法及び希土類化合物の塗布装置 |
WO2016175063A1 (ja) * | 2015-04-28 | 2016-11-03 | 信越化学工業株式会社 | 希土類磁石の製造方法及び希土類化合物の塗布装置 |
JP2018082146A (ja) * | 2016-08-31 | 2018-05-24 | ▲煙▼台正海磁性材料股▲ふん▼有限公司 | R‐Fe‐B系焼結磁石を製造する方法 |
US10017871B2 (en) | 2014-02-19 | 2018-07-10 | Shin-Etsu Chemical Co., Ltd. | Electrodepositing apparatus and preparation of rare earth permanent magnet |
JP2018528603A (ja) * | 2015-07-06 | 2018-09-27 | ダイソン・テクノロジー・リミテッド | マグネット |
JP2019075493A (ja) * | 2017-10-18 | 2019-05-16 | Tdk株式会社 | 磁石接合体 |
CN113808842A (zh) * | 2021-09-29 | 2021-12-17 | 赣州市钜磁科技有限公司 | 一种烧结钕铁硼磁体生产用烧结工艺 |
JP2022044560A (ja) * | 2020-09-07 | 2022-03-17 | 煙台東星磁性材料株式有限公司 | Nd-Fe-B系永久磁性体表面へのセラミック前駆体溶液吹き付け装置、及びNd-Fe-B系永久磁性体表面へのセラミック層形成方法。 |
US11810698B2 (en) | 2015-07-06 | 2023-11-07 | Dyson Technology Limited | Magnet |
Families Citing this family (20)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN102822912B (zh) * | 2010-03-30 | 2015-07-22 | Tdk株式会社 | 稀土类烧结磁铁以及其制造方法、马达以及汽车 |
FR2985085B1 (fr) * | 2011-12-23 | 2014-02-21 | Alstom Technology Ltd | Actionneur electromagnetique a aimants permanents et interrupteur-sectionneur mecanique actionne par un tel actionneur |
CN104051101B (zh) * | 2013-03-12 | 2018-04-27 | 北京中科三环高技术股份有限公司 | 一种稀土永磁体及其制备方法 |
DE102013205442A1 (de) * | 2013-03-27 | 2014-10-02 | Robert Bosch Gmbh | Pumpe mit Elektromotor |
JP6477723B2 (ja) * | 2014-12-12 | 2019-03-06 | 日立金属株式会社 | R−t−b系焼結磁石の製造方法 |
CN107004500B (zh) * | 2014-12-12 | 2019-04-09 | 日立金属株式会社 | R-t-b系烧结磁体的制造方法 |
CN107408454B (zh) * | 2015-03-13 | 2019-12-03 | 日立金属株式会社 | R-t-b系烧结磁体的制造方法、该方法所使用的涂布器件和涂布装置 |
JP6365393B2 (ja) | 2015-04-28 | 2018-08-01 | 信越化学工業株式会社 | 希土類磁石の製造方法及び希土類化合物の塗布装置 |
JP6459758B2 (ja) * | 2015-04-28 | 2019-01-30 | 信越化学工業株式会社 | 希土類磁石の製造方法及び希土類化合物の塗布装置 |
JP6394484B2 (ja) * | 2015-04-28 | 2018-09-26 | 信越化学工業株式会社 | 希土類磁石の製造方法及び希土類化合物の塗布装置 |
JP6350380B2 (ja) * | 2015-04-28 | 2018-07-04 | 信越化学工業株式会社 | 希土類磁石の製造方法 |
JP6361568B2 (ja) * | 2015-04-28 | 2018-07-25 | 信越化学工業株式会社 | 希土類磁石の製造方法及びスラリー塗布装置 |
KR20170009348A (ko) * | 2015-07-16 | 2017-01-25 | 엘에스산전 주식회사 | 영구자석을 포함한 전기자동차용 릴레이 및 그 제조방법 |
CN105070498B (zh) * | 2015-08-28 | 2016-12-07 | 包头天和磁材技术有限责任公司 | 提高磁体矫顽力的方法 |
JP2017216778A (ja) * | 2016-05-30 | 2017-12-07 | Tdk株式会社 | モータ |
CN107895644B (zh) * | 2017-11-24 | 2019-10-01 | 北京七星华创磁电科技有限公司 | 一种用于重稀土晶界扩渗的生产线及生产方法 |
CN108630368B (zh) * | 2018-06-11 | 2020-09-11 | 安徽大地熊新材料股份有限公司 | 一种高矫顽力钕铁硼磁体的表面涂覆浆料及钕铁硼磁体制备方法 |
KR101932551B1 (ko) * | 2018-06-15 | 2018-12-27 | 성림첨단산업(주) | 중희토 입계확산형 RE-Fe-B계 희토류 자석의 제조방법 및 이에 의해 제조된 중희토 입계확산형 RE-Fe-B계 희토류자석 |
CN114420437A (zh) * | 2020-01-13 | 2022-04-29 | 桂林电子科技大学 | 一种利用Dy制备的钕铁硼永磁材料及其制备方法 |
CN115440495A (zh) * | 2022-10-10 | 2022-12-06 | 烟台东星磁性材料股份有限公司 | 钕铁硼磁体矫顽力提升方法以及由该方法制备的磁体 |
Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2005109421A (ja) * | 2002-11-29 | 2005-04-21 | Neomax Co Ltd | 耐食性希土類系永久磁石の製造方法、耐食性希土類系永久磁石、ワークのディップスピンコーティング法およびワークの塗膜形成方法 |
WO2006100968A1 (ja) * | 2005-03-18 | 2006-09-28 | Ulvac, Inc. | 成膜方法及び成膜装置並びに永久磁石及び永久磁石の製造方法 |
JP2008147634A (ja) | 2006-11-17 | 2008-06-26 | Shin Etsu Chem Co Ltd | 希土類永久磁石の製造方法 |
JP2008270699A (ja) * | 2007-03-29 | 2008-11-06 | Hitachi Ltd | 希土類磁石及びその製造方法 |
JP2009200180A (ja) * | 2008-02-20 | 2009-09-03 | Ulvac Japan Ltd | 永久磁石の製造方法 |
Family Cites Families (23)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
GB1347764A (en) * | 1970-04-30 | 1974-02-27 | Gen Electric | Heat-aged sintered cobalt-rare earth intermetallic product and process |
US7335392B2 (en) | 2002-11-29 | 2008-02-26 | Neomax Co., Ltd. | Method for producing corrosion-resistant rare earth metal-based permanent magnet |
CN100361239C (zh) * | 2002-11-29 | 2008-01-09 | 株式会社新王磁材 | 抗腐蚀稀土金属基永磁体的制造方法、抗腐蚀稀土金属基永磁体 |
JP2005011973A (ja) | 2003-06-18 | 2005-01-13 | Japan Science & Technology Agency | 希土類−鉄−ホウ素系磁石及びその製造方法 |
JP3960966B2 (ja) | 2003-12-10 | 2007-08-15 | 独立行政法人科学技術振興機構 | 耐熱性希土類磁石の製造方法 |
MY142024A (en) | 2005-03-23 | 2010-08-16 | Shinetsu Chemical Co | Rare earth permanent magnet |
JP4702546B2 (ja) | 2005-03-23 | 2011-06-15 | 信越化学工業株式会社 | 希土類永久磁石 |
MY141999A (en) | 2005-03-23 | 2010-08-16 | Shinetsu Chemical Co | Functionally graded rare earth permanent magnet |
JP4702549B2 (ja) | 2005-03-23 | 2011-06-15 | 信越化学工業株式会社 | 希土類永久磁石 |
TWI413136B (zh) | 2005-03-23 | 2013-10-21 | Shinetsu Chemical Co | 稀土族永久磁體 |
TWI417906B (zh) | 2005-03-23 | 2013-12-01 | Shinetsu Chemical Co | 機能分級式稀土族永久磁鐵 |
JP4702548B2 (ja) | 2005-03-23 | 2011-06-15 | 信越化学工業株式会社 | 傾斜機能性希土類永久磁石 |
JP4702547B2 (ja) | 2005-03-23 | 2011-06-15 | 信越化学工業株式会社 | 傾斜機能性希土類永久磁石 |
JP2006281063A (ja) * | 2005-03-31 | 2006-10-19 | Tdk Corp | 表面処理用治具及び表面処理方法 |
CN101006534B (zh) * | 2005-04-15 | 2011-04-27 | 日立金属株式会社 | 稀土类烧结磁铁及其制造方法 |
JP4737431B2 (ja) * | 2006-08-30 | 2011-08-03 | 信越化学工業株式会社 | 永久磁石回転機 |
US20080241513A1 (en) * | 2007-03-29 | 2008-10-02 | Matahiro Komuro | Rare earth magnet and manufacturing method thereof |
US20100129538A1 (en) * | 2007-03-30 | 2010-05-27 | Tdk Corporation | Process for producing magnet |
CN101652822B (zh) * | 2007-07-27 | 2012-06-13 | 日立金属株式会社 | R-Fe-B系稀土类烧结磁铁 |
JP4672030B2 (ja) * | 2008-01-31 | 2011-04-20 | 日立オートモティブシステムズ株式会社 | 焼結磁石及びそれを用いた回転機 |
JP5256851B2 (ja) * | 2008-05-29 | 2013-08-07 | Tdk株式会社 | 磁石の製造方法 |
JP4896104B2 (ja) * | 2008-09-29 | 2012-03-14 | 株式会社日立製作所 | 焼結磁石及びそれを用いた回転機 |
JP4618390B1 (ja) * | 2009-12-16 | 2011-01-26 | Tdk株式会社 | 希土類焼結磁石製造方法及び塗布装置 |
-
2011
- 2011-03-04 JP JP2012503287A patent/JP5472444B2/ja active Active
- 2011-03-04 US US13/390,016 patent/US9154004B2/en active Active
- 2011-03-04 EP EP11750813.5A patent/EP2544199A4/en not_active Ceased
- 2011-03-04 CN CN201180003230.8A patent/CN102483980B/zh active Active
- 2011-03-04 WO PCT/JP2011/055067 patent/WO2011108704A1/ja active Application Filing
Patent Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2005109421A (ja) * | 2002-11-29 | 2005-04-21 | Neomax Co Ltd | 耐食性希土類系永久磁石の製造方法、耐食性希土類系永久磁石、ワークのディップスピンコーティング法およびワークの塗膜形成方法 |
WO2006100968A1 (ja) * | 2005-03-18 | 2006-09-28 | Ulvac, Inc. | 成膜方法及び成膜装置並びに永久磁石及び永久磁石の製造方法 |
JP2008147634A (ja) | 2006-11-17 | 2008-06-26 | Shin Etsu Chem Co Ltd | 希土類永久磁石の製造方法 |
JP2008270699A (ja) * | 2007-03-29 | 2008-11-06 | Hitachi Ltd | 希土類磁石及びその製造方法 |
JP2009200180A (ja) * | 2008-02-20 | 2009-09-03 | Ulvac Japan Ltd | 永久磁石の製造方法 |
Non-Patent Citations (1)
Title |
---|
See also references of EP2544199A4 |
Cited By (33)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN103890868B (zh) * | 2011-10-28 | 2017-05-03 | Tdk株式会社 | R‑t‑b系烧结磁铁 |
CN103890868A (zh) * | 2011-10-28 | 2014-06-25 | Tdk株式会社 | R-t-b系烧结磁铁 |
JP2014063996A (ja) * | 2012-08-31 | 2014-04-10 | Shin Etsu Chem Co Ltd | 希土類永久磁石の製造方法 |
JP2014063998A (ja) * | 2012-08-31 | 2014-04-10 | Shin Etsu Chem Co Ltd | 希土類永久磁石の製造方法 |
US10181377B2 (en) | 2012-08-31 | 2019-01-15 | Shin-Etsu Chemical Co., Ltd. | Production method for rare earth permanent magnet |
US10179955B2 (en) | 2012-08-31 | 2019-01-15 | Shin-Etsu Chemical Co., Ltd. | Production method for rare earth permanent magnet |
US10138564B2 (en) | 2012-08-31 | 2018-11-27 | Shin-Etsu Chemical Co., Ltd. | Production method for rare earth permanent magnet |
JP2014063997A (ja) * | 2012-08-31 | 2014-04-10 | Shin Etsu Chem Co Ltd | 希土類永久磁石の製造方法 |
JP2015065218A (ja) * | 2013-09-24 | 2015-04-09 | 大同特殊鋼株式会社 | RFeB系磁石の製造方法 |
US10017871B2 (en) | 2014-02-19 | 2018-07-10 | Shin-Etsu Chemical Co., Ltd. | Electrodepositing apparatus and preparation of rare earth permanent magnet |
JP2015154051A (ja) * | 2014-02-19 | 2015-08-24 | 信越化学工業株式会社 | 希土類永久磁石の製造方法 |
US10526715B2 (en) | 2014-02-19 | 2020-01-07 | Shin-Etsu Chemical Co., Ltd. | Preparation of rare earth permanent magnet |
US9845545B2 (en) | 2014-02-19 | 2017-12-19 | Shin-Etsu Chemical Co., Ltd. | Preparation of rare earth permanent magnet |
JP2016207977A (ja) * | 2015-04-28 | 2016-12-08 | 信越化学工業株式会社 | 希土類磁石の製造方法及び希土類化合物の塗布装置 |
US11424072B2 (en) | 2015-04-28 | 2022-08-23 | Shin-Etsu Chemical Co., Ltd. | Method for producing rare-earth magnets, and rare-earth-compound application device |
US10832864B2 (en) | 2015-04-28 | 2020-11-10 | Shin-Etsu Chemical Co., Ltd. | Method for producing rare-earth magnets, and rare-earth-compound application device |
WO2016175063A1 (ja) * | 2015-04-28 | 2016-11-03 | 信越化学工業株式会社 | 希土類磁石の製造方法及び希土類化合物の塗布装置 |
WO2016175059A1 (ja) * | 2015-04-28 | 2016-11-03 | 信越化学工業株式会社 | 希土類磁石の製造方法及び希土類化合物の塗布装置 |
WO2016175061A1 (ja) * | 2015-04-28 | 2016-11-03 | 信越化学工業株式会社 | 希土類磁石の製造方法及び希土類化合物の塗布装置 |
JP2016207980A (ja) * | 2015-04-28 | 2016-12-08 | 信越化学工業株式会社 | 希土類磁石の製造方法及び希土類化合物の塗布装置 |
US11224890B2 (en) | 2015-04-28 | 2022-01-18 | Shin-Etsu Chemical Co., Ltd. | Method for producing rare-earth magnets, and rare-earth-compound application device |
JP2016207975A (ja) * | 2015-04-28 | 2016-12-08 | 信越化学工業株式会社 | 希土類磁石の製造方法及び希土類化合物の塗布装置 |
US10790076B2 (en) | 2015-04-28 | 2020-09-29 | Shin-Etsu Chemical Co., Ltd. | Method for producing rare-earth magnets, and rare-earth-compound application device |
JP2018528603A (ja) * | 2015-07-06 | 2018-09-27 | ダイソン・テクノロジー・リミテッド | マグネット |
US11810698B2 (en) | 2015-07-06 | 2023-11-07 | Dyson Technology Limited | Magnet |
JP2018082146A (ja) * | 2016-08-31 | 2018-05-24 | ▲煙▼台正海磁性材料股▲ふん▼有限公司 | R‐Fe‐B系焼結磁石を製造する方法 |
JP2019075493A (ja) * | 2017-10-18 | 2019-05-16 | Tdk株式会社 | 磁石接合体 |
JP7020051B2 (ja) | 2017-10-18 | 2022-02-16 | Tdk株式会社 | 磁石接合体 |
US11335483B2 (en) | 2017-10-18 | 2022-05-17 | Tdk Corporation | Magnet structure |
JP2022044560A (ja) * | 2020-09-07 | 2022-03-17 | 煙台東星磁性材料株式有限公司 | Nd-Fe-B系永久磁性体表面へのセラミック前駆体溶液吹き付け装置、及びNd-Fe-B系永久磁性体表面へのセラミック層形成方法。 |
JP7202763B2 (ja) | 2020-09-07 | 2023-01-12 | 煙台東星磁性材料株式有限公司 | Nd-Fe-B系永久磁性体表面へのセラミック前駆体溶液吹き付け装置、及びNd-Fe-B系永久磁性体表面へのセラミック層形成方法。 |
US11908600B2 (en) | 2020-09-07 | 2024-02-20 | Yantai Dongxing Magnetic Materials Inc | Preparation device and method of ceramic coating on a sintered type NdFeB permanent magnet |
CN113808842A (zh) * | 2021-09-29 | 2021-12-17 | 赣州市钜磁科技有限公司 | 一种烧结钕铁硼磁体生产用烧结工艺 |
Also Published As
Publication number | Publication date |
---|---|
CN102483980A (zh) | 2012-05-30 |
US9154004B2 (en) | 2015-10-06 |
EP2544199A4 (en) | 2017-11-29 |
EP2544199A1 (en) | 2013-01-09 |
JP5472444B2 (ja) | 2014-04-16 |
US20120139388A1 (en) | 2012-06-07 |
JPWO2011108704A1 (ja) | 2013-06-27 |
CN102483980B (zh) | 2016-09-07 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
JP5472444B2 (ja) | 希土類焼結磁石及びモータ | |
JP4656325B2 (ja) | 希土類永久磁石、その製造方法、並びに永久磁石回転機 | |
TWI408705B (zh) | A rare earth permanent magnet, a method for manufacturing the same, and a permanent magnet rotating machine | |
US8211327B2 (en) | Preparation of rare earth permanent magnet material | |
EP2254131B1 (en) | MANUFACTURING METHOD OF A Nd-BASED SINTERED MAGNET | |
JP4737431B2 (ja) | 永久磁石回転機 | |
JP6107547B2 (ja) | 希土類永久磁石の製造方法 | |
JP4702549B2 (ja) | 希土類永久磁石 | |
JP6090589B2 (ja) | 希土類永久磁石の製造方法 | |
BRPI0702848B1 (pt) | Método para a preparação de material de magneto permanente de terras raras | |
JP6107545B2 (ja) | 希土類永久磁石の製造方法 | |
WO2014034851A1 (ja) | 希土類永久磁石の製造方法 | |
JP4919109B2 (ja) | 永久磁石回転機及び永久磁石回転機用永久磁石セグメントの製造方法 | |
JP2012217270A (ja) | 回転機用磁石、回転機及び回転機用磁石の製造方法 | |
JP2011019401A (ja) | 永久磁石回転機用永久磁石セグメントの製造方法 | |
JP2011108776A (ja) | 永久磁石の製造方法 |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
WWE | Wipo information: entry into national phase |
Ref document number: 201180003230.8 Country of ref document: CN |
|
121 | Ep: the epo has been informed by wipo that ep was designated in this application |
Ref document number: 11750813 Country of ref document: EP Kind code of ref document: A1 |
|
WWE | Wipo information: entry into national phase |
Ref document number: 13390016 Country of ref document: US |
|
WWE | Wipo information: entry into national phase |
Ref document number: 2011750813 Country of ref document: EP |
|
WWE | Wipo information: entry into national phase |
Ref document number: 2012503287 Country of ref document: JP |
|
NENP | Non-entry into the national phase |
Ref country code: DE |