WO2014058067A1 - Poudre de ferrite de sr, procédé de fabrication d'un aimant fritté en ferrite de sr, moteur et générateur - Google Patents

Poudre de ferrite de sr, procédé de fabrication d'un aimant fritté en ferrite de sr, moteur et générateur Download PDF

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WO2014058067A1
WO2014058067A1 PCT/JP2013/077837 JP2013077837W WO2014058067A1 WO 2014058067 A1 WO2014058067 A1 WO 2014058067A1 JP 2013077837 W JP2013077837 W JP 2013077837W WO 2014058067 A1 WO2014058067 A1 WO 2014058067A1
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ferrite
powder
magnet
calcined body
sintered
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Japanese (ja)
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田口　仁
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Tdk株式会社
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Priority to CN201380040883.2A priority Critical patent/CN104507889A/zh
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Definitions

  • the present invention relates to a method for producing Sr ferrite powder and a sintered Sr ferrite magnet, and a motor and a generator including the Sr ferrite sintered magnet obtained by the production method.
  • M type Sr ferrite As a magnetic material used for a ferrite sintered magnet, Ba ferrite, Sr ferrite, and Ca ferrite having a hexagonal crystal structure are known. In recent years, among them, magnetoplumbite type (M type) Sr ferrite is mainly used as a magnet material for motors and the like.
  • the M-type ferrite is represented by a general formula of AFe 12 O 19 , for example.
  • Sr ferrite has Sr at the A site of the crystal structure.
  • Patent Document 1 discloses a technique for improving the residual magnetic flux density (Br) and the coercive force (HcJ) by replacing a part of the A site and the B site with a specific amount of rare earth element and Co. .
  • Sr ferrite magnets used in motors and generators are required to be reduced in size and weight, and in order to cope with this, it is required to further increase the magnetic characteristics.
  • Patent Document 1 it is effective to improve the magnetic characteristics by controlling the composition of main crystal grains constituting the Sr ferrite sintered magnet.
  • the composition of main crystal grains constituting the Sr ferrite sintered magnet even if only the composition of the crystal grains is controlled, it is difficult to greatly improve the magnetic characteristics of the conventional Sr ferrite sintered magnet.
  • refine the structure As a means for refining the structure, it can be considered that the calcined body used as a raw material of the sintered Sr ferrite magnet is atomized.
  • a method for atomizing the calcined body a method of mechanically crushing the calcined body and lengthening the crushing time can be mentioned.
  • the mechanically pulverized in this way the particle size distribution becomes wide.
  • the manufacturing cost increases due to increased power consumption, equipment wear, and the like, and the yield decreases.
  • anisotropic Sr ferrite sintered magnets whose crystal orientation is in the c-axis direction are currently mainstream.
  • an anisotropic Sr ferrite sintered magnet is manufactured, it is necessary to advance the ferritization reaction sufficiently in the calcining step in order to increase the orientation of the ferrite particles by the magnetic field at the stage of forming the molded body. .
  • calcination and baking were generally performed at a high temperature of 1250 ° C. or higher.
  • energy costs in the calcination step and the firing step increased, and ferrite particles grew to several ⁇ m to several tens of ⁇ m.
  • This invention is made
  • the present inventors have studied various methods for producing Sr ferrite powder used as a raw material in order to refine the structure of the sintered Sr ferrite magnet. As a result, it has been found that the temperature at which Sr ferrite is generated can be significantly reduced by adding a compound having Li as a constituent element. And it discovered that the Sr ferrite sintered magnet which has high Br can be manufactured by using Sr ferrite powder obtained by calcining at low temperature, and came to complete this invention.
  • a mixture containing an iron compound powder, a strontium compound powder, and a compound powder containing Li as a constituent element is fired at 850 to 1050 ° C. to obtain a hexagonal crystal structure.
  • a Sr ferrite powder including a calcined body or a pulverized powder thereof having a calcined step of obtaining a calcined body containing 0.01 to 0.5% by mass of Li in terms of Li 2 O A manufacturing method is provided.
  • a fine Sr ferrite powder having high saturation magnetization ( ⁇ s ) can be easily obtained.
  • the present inventors presume this reason as follows. That is, in the method for producing Sr ferrite powder of the present invention, a mixture containing a powder of a compound having Li as a constituent element is used as a raw material for producing Sr ferrite powder. It is believed that this Li has the action of promoting the formation of Sr ferrite, and as a result, it is possible to obtain a calcined body having a high saturation magnetization by forming Sr ferrite at a calcining temperature of 800 to 1050 ° C. Yes.
  • the grain growth of Sr ferrite can be sufficiently suppressed. If such a calcined body is pulverized as necessary, a sufficiently fine Sr ferrite powder having high saturation magnetization can be easily obtained.
  • the Sr ferrite powder obtained in this way produces Sr ferrite sintered magnets that are required to have high Br because the particles are fine and have high uniformity and also have high saturation magnetization. It can be particularly suitably used as a raw material for the purpose.
  • the method for producing Sr ferrite powder of the present invention preferably includes a pulverization step of pulverizing the calcined body to obtain a pulverized powder containing Sr ferrite.
  • a pulverization step of pulverizing the calcined body to obtain a pulverized powder containing Sr ferrite.
  • the specific surface area by the BET method of the calcined body obtained in the calcining step is preferably 2 m 2 / g or more and the saturation magnetization is 67 emu / g or more.
  • Such a calcined body is finer and has a high saturation magnetization. For this reason, when the Sr ferrite powder containing this calcined body or its pulverized powder is sintered to produce a Sr ferrite sintered magnet, even if the sintering temperature is lowered, Sr ferrite sintered having a sufficiently high Br is obtained.
  • a magnetized magnet can be manufactured.
  • the mixture used in the calcining step further includes a powder of a compound having Na as a constituent element.
  • a powder of a compound having Na as a constituent element.
  • a mixture containing a powder of an iron compound, a powder of a strontium compound, and a powder of a compound having Li as a constituent element is fired at 850 to 1050 ° C. to form Sr having a hexagonal crystal structure.
  • a calcination step for obtaining a calcined body containing ferrite and containing 0.01 to 0.5% by mass of Li in terms of Li 2 O, and pulverizing to obtain a pulverized powder containing Sr ferrite by crushing the calcined body Sr ferrite sintering comprising: a step, a molding step of forming a pulverized powder in a magnetic field to obtain a molded body, and a sintering step of firing the molded body at 1000 to 1250 ° C. to obtain a Sr ferrite sintered magnet
  • a method for manufacturing a magnet is provided.
  • an Sr ferrite sintered magnet having a high Br can be produced by a simple process.
  • the present inventors infer that this reason is as follows. That is, in the method for producing a sintered Sr ferrite magnet of the present invention, the Sr ferrite sintered magnet is produced using a mixture containing a powder of a compound having Li as a constituent element. This Li has an action of promoting the formation of Sr ferrite, and it is considered that a calcined body having a high saturation magnetization can be obtained at a calcining temperature of 850 to 1050 ° C.
  • the grain growth of Sr ferrite can be sufficiently suppressed. If such a calcined body is pulverized, a sufficiently fine Sr ferrite powder having a high saturation magnetization can be easily obtained.
  • the Sr ferrite powder thus obtained has fine particles, high uniformity, and high saturation magnetization. For this reason, such a sintered Sr ferrite magnet has good sinterability, and an Sr ferrite sintered magnet can be obtained at a low sintering temperature. For this reason, it is considered that during sintering, abnormal grain growth is suppressed, the density is improved while maintaining a sufficiently fine structure, and an Sr ferrite sintered magnet having high Br can be obtained.
  • Li added at the raw material stage is considered to exert an effect of promoting sintering, and this contributes to reduction of the sintering temperature and refinement of the structure of the sintered Sr ferrite magnet. Is also possible.
  • the production method of the present invention is a production method using a mixture obtained by mixing raw material powders, so that Sr ferrite can be produced in a simple process without complicated operations. Sintered magnets can be manufactured. That is, it can be said that the manufacturing method of the Sr ferrite sintered magnet of the present invention is a manufacturing method suitable for mass production of the Sr ferrite sintered magnet.
  • the mixture preferably contains a powder of a compound having Na as a constituent element.
  • the calcination temperature and the sintering temperature can be further lowered, and the structure of the sintered Sr ferrite magnet can be further refined.
  • the present invention provides a motor including a sintered Sr ferrite magnet obtained by the above-described manufacturing method.
  • the motor of the present invention has high efficiency because it includes a sintered Sr ferrite magnet having a high Br.
  • the present invention provides a generator including a sintered Sr ferrite magnet obtained by the above-described manufacturing method. Since the generator of the present invention includes the sintered Sr ferrite magnet having a high Br, the generator has high efficiency.
  • the present invention it is possible to provide a method for producing an Sr ferrite sintered magnet capable of producing an Sr ferrite sintered magnet having a high Br by a simple process. Moreover, the manufacturing method of Sr ferrite powder suitable for manufacturing such a Sr ferrite sintered magnet can be provided. Furthermore, a motor and a generator having high efficiency can be provided by using the Sr ferrite sintered magnet described above.
  • FIG. 3 is an electron micrograph of Sr ferrite powder in Example 1-2. It is sectional drawing which shows typically suitable embodiment of the motor of this invention.
  • FIG. 4 is a sectional view taken along line IV-IV of the motor shown in FIG. 3.
  • the manufacturing method of the Sr ferrite powder of the present embodiment includes an iron compound powder, a strontium compound powder, and a mixing step of preparing a mixture by mixing a compound powder having lithium (Li) as a constituent element, the mixture Is calcined at 850 to 1050 ° C. to obtain a calcined body containing Sr ferrite having a hexagonal crystal structure, and a pulverizing process for crushing the calcined body to obtain Sr ferrite powder.
  • a compound powder having lithium (Li) as a constituent element
  • the mixture Is calcined at 850 to 1050 ° C. to obtain a calcined body containing Sr ferrite having a hexagonal crystal structure
  • a pulverizing process for crushing the calcined body to obtain Sr ferrite powder.
  • the mixing step is a step of preparing a mixture for calcination.
  • the starting materials are weighed and blended at a predetermined ratio, and mixed with a wet attritor or a ball mill for about 1 to 20 hours and pulverized.
  • the starting material include iron compound powder, strontium compound powder, and lithium compound powder having lithium as a constituent element.
  • an oxide or a compound such as carbonate, hydroxide, or nitrate that becomes an oxide by firing can be used.
  • examples of such compounds include SrCO 3 and Fe 2 O 3 .
  • La (OH) 3 and Co 3 O 4 may be added.
  • the lithium compound include oxides, carbonates, silicates, and organic compounds (dispersants) containing lithium.
  • the mixing amount of the lithium compound is such that the lithium content in the mixture obtained in the mixing step is 0.01 to 0.5% by mass, preferably 0.05 to 0.3% by mass in terms of Li 2 O. Mix.
  • the mixing step it is preferable to add a sodium compound having sodium as a constituent element in addition to the above-described lithium compound.
  • a sodium compound having sodium as a constituent element in addition to the above-described lithium compound.
  • the ferrite formation reaction is promoted, and a calcined body containing Sr ferrite can be obtained in a short time even if the calcining temperature in the calcining step is lowered.
  • a calcined body having a higher Sr ferrite content can be obtained.
  • the mixing amount of the sodium compound is such that the sodium content in the mixture obtained in the mixing step is preferably 0.005 to 0.8% by mass, more preferably 0.01 to 0.6% by mass in terms of Na 2 O. Mix to be.
  • Sr ferrite powder having a high saturation magnetization ( ⁇ s ) can be produced in a shorter calcining time.
  • the total content of the lithium compound and sodium compound in the mixture is preferably 0.01 to 1.0% by mass, more preferably 0.02 when the lithium compound and sodium compound are converted to Li 2 O and Na 2 O, respectively. Is 0.5 mass. By setting it as such a range, Sr ferrite powder with high saturation magnetization ((sigma) s ) can be manufactured in a shorter calcination time.
  • the average particle diameter of each starting material is not particularly limited, and is, for example, 0.1 to 2.0 ⁇ m.
  • the specific surface area of each starting material according to the BET method is preferably 2 m 2 / g or more. Thereby, a finer Sr ferrite powder can be obtained.
  • the mixture prepared in the mixing step may be in the form of a powder or may be dispersed in a slurry containing a solvent.
  • the calcining step is a step of calcining the mixture obtained in the mixing step. Calcination can be performed in an oxidizing atmosphere such as air.
  • the firing temperature (calcination temperature) in the calcination step is 850 to 1050 ° C. From the viewpoint of obtaining Sr ferrite powder having high saturation magnetization, the lower limit of the calcining temperature is preferably 900 ° C. On the other hand, from the viewpoint of obtaining sufficiently fine Sr ferrite powder, the upper limit of the calcining temperature is preferably 1000 ° C., more preferably 950 ° C.
  • the calcination time at the calcination temperature is preferably 0.5 to 5 hours, more preferably 1 to 3 hours.
  • the content of Sr ferrite in the calcined body obtained by calcining is preferably 70% by mass or more, and more preferably 90% by mass or more.
  • the mixture used in the calcining step contains a lithium compound, Sr ferrite having a hexagonal crystal structure can be sufficiently generated even at the calcining temperature described above.
  • the saturation magnetization of the calcined body is preferably 67 emu / g or more, more preferably 70 emu / g or more, and further preferably 70.5 emu / g or more.
  • VSM vibrating sample magnetometer
  • the specific surface area of the calcined body by the BET method is preferably 15 m 2 / g or less, more preferably 10 m 2 / g or less, from the viewpoint of improving the moldability when producing a molded body. More preferably, it is 7 m 2 / g or less.
  • the specific surface area in this specification can be measured using a commercially available BET specific surface area measuring apparatus (manufactured by Mountaintech, trade name: HM Model-1210).
  • the calcined body obtained by calcination of the mixture obtained in the mixing step is pulverized to prepare pulverized powder.
  • the pulverization may be performed in one stage, or may be performed in two stages, a coarse pulverization process and a fine pulverization process. Since the calcined body is usually granular or massive, it is preferable to first perform a coarse pulverization step.
  • a coarse pulverized powder is prepared by performing dry pulverization using a vibrating rod mill or the like.
  • the coarsely pulverized powder thus prepared is wet pulverized using a wet attritor, ball mill, jet mill or the like to obtain a finely pulverized powder.
  • the pulverization time is, for example, 30 minutes to 10 hours when using a wet attritor, and 5 to 50 hours when using a ball mill. These times are preferably adjusted appropriately depending on the pulverization method.
  • calcination is performed at a temperature lower than that in the prior art, so the primary particles of Sr ferrite in the calcined body are finer than in the past. Therefore, the pulverization process (particularly the pulverization process) has a strong meaning of dispersing fine primary particles.
  • powders such as SiO 2 , CaCO 3 , SrCO 3, and BaCO 3 that are subcomponents may be added.
  • sinterability can be improved and magnetic properties can be improved.
  • these subcomponents may flow out together with the solvent of the slurry when forming in a wet manner, it is preferable to add more than the target content in the sintered Sr ferrite magnet.
  • polyhydric alcohol in the pulverization step in addition to the above-mentioned subcomponents.
  • the addition amount of the polyhydric alcohol is 0.05 to 5.0% by mass, preferably 0.1 to 3.0% by mass, more preferably 0.3 to 2.0% by mass with respect to the addition target. .
  • the added polyhydric alcohol is thermally decomposed and removed in the sintering process.
  • the specific surface area by the BET method of the pulverized powder obtained in the pulverization step is preferably 6 m 2 / g or more, more preferably 8 m, from the viewpoint of sufficiently finening the structure of the finally obtained Sr ferrite sintered magnet. 2 / g or more.
  • the specific surface area of the pulverized powder by the BET method is preferably 12 m 2 / g or less, more preferably 10 m 2 / g or less, from the viewpoint of improving the moldability when producing a molded body.
  • the structure of the sintered Sr ferrite magnet is further refined while maintaining the simplicity of the process, and the Sr The magnetic properties of the sintered ferrite magnet can be further improved.
  • Sr ferrite powder can be obtained through the above steps. Since the Sr ferrite powder thus obtained is fired using a mixture containing lithium, it is sufficiently fine, has high particle uniformity, and has a high ⁇ s .
  • the content of Sr ferrite having a hexagonal crystal structure in the Sr ferrite powder is preferably 50% by mass or more, more preferably 70% by mass or more, and further preferably 80% by mass or more.
  • the Sr ferrite powder may contain unreacted raw materials such as an iron compound and a strontium compound, a lithium compound, a sodium compound, and other components as components other than the Sr ferrite.
  • Other components include oxides and composite oxides having at least one selected from K (potassium), Si (silicon), Ca (calcium), Sr (strontium) and Ba (barium). Examples of the oxide include K 2 O, SiO 2 , CaO, SrO, and BaO.
  • the saturation magnetization of the Sr ferrite powder is preferably 67 emu / g or more, more preferably 70 emu / g or more, and further preferably 70.5 emu / g or more.
  • the method for producing a sintered Sr ferrite magnet of this embodiment includes a mixing step of preparing a mixture by mixing an iron compound powder, a strontium compound powder, and a compound powder having lithium as a constituent element; Calcining at 850 to 1050 ° C. to obtain a calcined body containing Sr ferrite having a hexagonal crystal structure, crushing process to crush the calcined body to obtain Sr ferrite powder, and Sr ferrite powder in a magnetic field
  • the mixing step, calcination step, and pulverization step are the same as the above-described method for producing Sr ferrite powder.
  • the overlapping process will not be described, and the forming process and the sintering process will be described.
  • the pulverized powder obtained in the pulverization process is molded in a magnetic field to form a molded body.
  • the molding in the magnetic field may be performed by either dry molding or wet molding, and is preferably wet molding from the viewpoint of increasing the degree of magnetic orientation.
  • a slurry can be prepared by blending a pulverized powder and a dispersion medium and pulverizing to prepare a slurry, and a molded product can be produced using the slurry. Concentration of the slurry can be performed by centrifugation, filter press, or the like.
  • the solid content in the slurry is preferably 30 to 85% by mass.
  • water or a non-aqueous solvent can be used as the dispersion medium of the slurry.
  • a surfactant such as gluconic acid, gluconate, or sorbitol may be added to the slurry.
  • molding is performed in a magnetic field to produce a molded body.
  • the molding pressure is, for example, 0.1 to 0.5 ton / cm 2
  • the applied magnetic field is, for example, 5 to 15 kOe.
  • the compact is fired to produce a sintered body.
  • Firing is usually performed in an oxidizing atmosphere such as air.
  • the firing temperature is 1000 to 1250 ° C., preferably 1100 to 1200 ° C.
  • the firing time at the firing temperature is preferably 0.5 to 3 hours.
  • FIG. 1 is a perspective view schematically showing a Sr ferrite sintered magnet obtained by the manufacturing method of the present embodiment.
  • the anisotropic Sr ferrite sintered magnet 10 has a curved shape so that the end surface is arcuate, and generally has a shape called an arc segment shape, a C shape, a tile shape, or an arc shape. is doing.
  • the Sr ferrite sintered magnet 10 is suitably used as a magnet for a motor or a generator, for example.
  • Sr ferrite sintered magnet 10 contains crystal grains of M-type Sr ferrite having a hexagonal crystal structure as a main component.
  • Sr ferrite is represented by the following formula (1), for example. SrFe 12 O 19 (1)
  • Sr at the A site and Fe at the B site may be partially substituted by impurities or intentionally added elements. Further, the ratio between the A site and the B site may be slightly shifted.
  • the Sr ferrite can be expressed by, for example, the following general formula (2).
  • x and y are, for example, 0.1 to 0.5
  • z is 0.7 to 1.2.
  • M in the general formula (2) is, for example, one or more selected from the group consisting of Co (cobalt), Zn (zinc), Ni (nickel), Mn (manganese), Al (aluminum), and Cr (chromium). It is an element.
  • R in the general formula (3) is, for example, one or more elements selected from the group consisting of La (lanthanum), Ce (cerium), Pr (praseodymium), Nd (neodymium), and Sm (samarium). .
  • the ratio of the Sr ferrite phase in the sintered Sr ferrite magnet 10 is preferably 95% or more, more preferably 97% or more, and further preferably 99% or more.
  • the ratio of Sr ferrite phase in Sr ferrite sintered magnet 10 (%) is the theoretical value of the saturation magnetization of the Sr ferrite sigma t, when the actually measured values ⁇ s, ( ⁇ s / ⁇ t) ⁇ 100 formula Can be obtained.
  • the Sr ferrite sintered magnet 10 contains a component different from Sr ferrite as a subcomponent.
  • the subcomponent include alkali metal compounds having Li (lithium) and / or Na (sodium) as constituent elements.
  • the alkali metal compound include oxides such as Li 2 O and Na 2 O and silicate glass.
  • the Li content in the sintered Sr ferrite magnet 10 is 0.01 to 0.5% by mass, preferably 0.01 to 0.3% by mass in terms of Li 2 O.
  • the content of Na in the sintered Sr ferrite magnet 10 is 0.01 to 0.2% by mass in terms of Na 2 O.
  • the total content of Li and Na in the Sr ferrite sintered magnet 10 is 0.02 to 0.5 mass% when Li and Na are converted to Li 2 O and Na 2 O, respectively.
  • the content of Li and / or Na in the Sr ferrite sintered magnet 10 becomes excessive, white powder tends to be generated on the surface.
  • the content of Li and / or Na in the Sr ferrite sintered magnet 10 becomes too small, the time required for sintering tends to become longer.
  • the Sr ferrite sintered magnet 10 may contain an arbitrary component in addition to the above-described alkali metal compound as a subcomponent.
  • examples of such components include oxides and composite oxides having at least one selected from K (potassium), Si (silicon), Ca (calcium), Sr (strontium), and Ba (barium).
  • examples of the oxide include K 2 O, SiO 2 , CaO, SrO, and BaO.
  • the Si content in the sintered Sr ferrite magnet 10 is, for example, 0.1 to 1.0 mass% in terms of SiO 2 .
  • the Sr content in the sintered Sr ferrite magnet 10 is, for example, 10 to 13% by mass in terms of SrO.
  • the Sr ferrite sintered magnet 10 may contain Ba.
  • the Ba content in the sintered Sr ferrite magnet 10 is, for example, 0.01 to 2.0 mass% in terms of BaO.
  • the Ca content in the sintered Sr ferrite magnet 10 is, for example, 0.05 to 2% by mass in terms of CaO.
  • the Sr ferrite sintered magnet 10 may contain impurities contained in the raw materials and inevitable components derived from the manufacturing equipment. Examples of such components include Ti (titanium), Cr (chromium), Mn (manganese), Mo (molybdenum), V (vanadium), and Al (aluminum) oxides.
  • the subcomponents are mainly contained in the grain boundaries of the Sr ferrite crystal grains in the Sr ferrite sintered magnet 10.
  • the content of each component of the sintered Sr ferrite magnet 10 can be measured by fluorescent X-ray analysis and inductively coupled plasma emission spectroscopic analysis (ICP analysis).
  • Sr ferrite sintered magnet 10 is, for example, for fuel pump, power window, ABS (anti-lock brake system), fan, wiper, power steering, active suspension, starter, door lock, It can be used as a magnet for an automobile motor such as an electric mirror. Also for FDD spindle, VTR capstan, VTR rotary head, VTR reel, VTR loading, VTR camera capstan, VTR camera rotary head, VTR camera zoom, VTR camera focus, radio cassette etc. It can be used as a magnet for motors for OA / AV devices such as CD / DVD / MD spindle, CD / DVD / MD loading, and CD / DVD optical pickup.
  • OA / AV devices such as CD / DVD / MD spindle, CD / DVD / MD loading, and CD / DVD optical pickup.
  • a magnet for a motor for home appliances such as an air conditioner compressor, a freezer compressor, an electric tool drive, a dryer fan, a shaver drive, an electric toothbrush and the like.
  • a magnet for a motor for FA equipment such as a robot shaft, joint drive, robot main drive, machine tool table drive, machine tool belt drive and the like.
  • the Sr ferrite sintered magnet 10 is attached to the above-mentioned motor member and installed in the motor. Since the Sr ferrite sintered magnet 10 has high Br, various motors including the Sr ferrite sintered magnet 10 have high efficiency.
  • FIG. 3 is a cross-sectional view schematically showing an embodiment of the motor 30 including the Sr ferrite sintered magnet 10.
  • the motor 30 of the present embodiment is a DC motor with a brush, and includes a bottomed cylindrical housing 31 (stator) and a rotatable rotor 32 disposed concentrically on the inner peripheral side of the housing 31.
  • the rotor 32 includes a rotor shaft 36 and a rotor core 37 fixed on the rotor shaft 36.
  • a bracket 33 is fitted in the opening of the housing 31, and the rotor core is accommodated in a space formed by the housing 31 and the bracket 33.
  • the rotor shaft 36 is rotatably supported by bearings 34 and 35 provided at the center portion of the housing 31 and the center portion of the bracket 33 so as to face each other.
  • Two C-type Sr ferrite sintered magnets 10 are fixed to the inner peripheral surface of the cylindrical portion of the housing 31 so as to face each other.
  • FIG. 4 is a cross-sectional view taken along line IV-IV of the motor 30 in FIG.
  • the Sr ferrite sintered magnet 10 that is a motor magnet is bonded to the inner peripheral surface of the housing 31 with an adhesive, with the outer peripheral surface serving as an adhesive surface. Since the Sr ferrite sintered magnet 10 has sufficiently suppressed the precipitation of foreign substances such as powder on the surface, the adhesion between the housing 31 and the Sr ferrite sintered magnet 10 is good. Therefore, the motor 30 has excellent reliability as well as excellent characteristics.
  • sintered Sr ferrite magnet 10 are not limited to motors and generators.
  • the shape of the Sr ferrite sintered magnet is not limited to the shape shown in FIG. 1 and can be appropriately changed to a shape suitable for each application described above.
  • the calcined body is pulverized to obtain Sr ferrite powder.
  • the Sr ferrite powder obtained by the production method of the present invention may be a calcined body that has not been pulverized.
  • the above-mentioned Fe 2 O 3 powder and SrCO 3 powder were mixed while being pulverized for 16 hours using a wet ball mill to obtain a slurry.
  • a slurry was added lithium carbonate powder.
  • the addition amount at this time was set to 0.19% by mass in terms of Li 2 O with respect to the total mass of the Fe 2 O 3 powder and the SrCO 3 powder.
  • the slurry was spray-dried to obtain a granular mixture having a particle size of about 10 ⁇ m.
  • the mixture was fired in the air at a calcining temperature T 1 (800 to 1100 ° C.) shown in Table 1 for 1 hour to obtain a granular calcined body containing Sr ferrite having a hexagonal crystal structure.
  • the magnetic properties (saturation magnetization and coercive force) of the obtained calcined body were measured using a commercially available vibrating sample magnetometer (VSM).
  • VSM vibrating sample magnetometer
  • the measurement method was as follows. Magnetization ( ⁇ ) in a magnetic field (Hex) of 16 kOe to 19 kOe was measured by VSM (manufactured by Toei Kogyo Co., Ltd., trade name: VSM-3 type). Then, the value of ⁇ ( ⁇ s ) when Hex is infinite was calculated by the saturation asymptotic rule. That is, ⁇ was plotted against 1 / Hex 2 and linear approximation was performed, and a value obtained by extrapolating 1 / Hex 2 ⁇ 0 was obtained. The correlation coefficient at this time was 99% or more. Moreover, the specific surface area by BET method of the obtained calcined body was measured. These measurement results are summarized in Table 1.
  • the Li 2 O equivalent content of Li in the obtained calcined body was measured using a commercially available ICP analyzer. As a result, the Li content in terms of Li 2 O in Examples 1-1 to 1-5 and Comparative Examples 1-1 to 1-2 was 0.19% by mass.
  • FIG. 2 is an electron micrograph of pulverized powder (Sr ferrite powder) obtained by wet pulverizing the calcined body of Example 1-2 with a ball mill. This pulverized powder did not contain coarse particles having a particle size of 1 ⁇ m or more.
  • Example 2-1 to Example 2-3 A granular calcined body containing Sr ferrite having a hexagonal crystal structure was obtained in the same manner as in Example 1-2 (T 1 : 900 ° C.). The content of Li in terms of Li 2 O in the obtained calcined body was measured in the same manner as in Examples 1-1 to 1-5. As a result, the Li content in terms of Li 2 O was 0.18% by mass.
  • Sorbitol, SiO 2 powder and CaCO 3 powder were added to 130 g of this calcined body.
  • the amount of each additive was 1% by mass of sorbitol, 0.6% by mass of SiO 2 powder, and 1.4% by mass of CaCO 3 powder based on the calcined body.
  • the calcined body was wet-ground for 22 hours using a ball mill to obtain a slurry.
  • the specific surface area of the Sr ferrite powder by the BET method of the pulverized powder after the wet pulverization was 12 m 2 / g.
  • the magnetic properties were measured using a BH tracer with a maximum applied magnetic field of 25 kOe.
  • HcJ, Br, and 4PI max were obtained, and the degree of orientation (Br / 4PI max ) was calculated.
  • the density of the sintered Sr ferrite magnet and the content of Li in terms of Li 2 O were measured by Archimedes method and fluorescent X-ray analysis, respectively. These results are shown in Table 5.
  • the method for measuring the Li content in the sintered Sr ferrite magnet is the same as in Example 1-1, and the numerical values in Table 5 are the contents in terms of Li 2 O.
  • Sr ferrite sintered magnets were produced in the same manner as in Examples 2-1 to 2-3 except that the calcined body thus obtained was used.
  • the specific surface area by BET method of the pulverized powder after wet pulverization was 12 m 2 / g.
  • Sintering temperature T 2 of each of the comparative examples are as shown in Table 5.
  • the magnetic properties of the obtained Sr ferrite sintered magnet were measured in the same manner as in Examples 2-1 to 2-3. Table 5 shows the measurement results.
  • Comparative Example 2-4 to Comparative Example 2-6 In the same manner as in Comparative Example 1-12 (T 1 : 900 ° C.), a granular calcined body containing Sr ferrite having a hexagonal crystal structure was obtained. The magnetic properties of the obtained calcined body were measured in the same manner as in Examples 2-1 to 2-3. As a result, ⁇ : 55.9 emu / g and HcJ: 1985 Oe.
  • Sr ferrite sintered magnets were produced in the same manner as in Examples 2-1 to 2-3 except that the calcined body thus obtained was used.
  • the specific surface area by BET method of the pulverized powder after wet pulverization was 12 m 2 / g.
  • Sintering temperature T 2 of each of the comparative examples are as shown in Table 5.
  • the magnetic properties of the obtained Sr ferrite sintered magnet were measured in the same manner as in Examples 2-1 to 2-3. These results are shown in Table 5.
  • Sr ferrite sintered magnets were produced in the same manner as in Examples 2-1 to 2-3 except that the calcined body thus obtained was used.
  • the specific surface area by BET method of the pulverized powder after wet pulverization was 12 m 2 / g.
  • Sintering temperature T 2 of each of the comparative examples are as shown in Table 5.
  • the magnetic properties of the obtained Sr ferrite sintered magnet were measured in the same manner as in Examples 2-1 to 2-3. These results are shown in Table 5.
  • the sintered Sr ferrite magnets of Examples 2-1 to 2-3 had higher density, higher Br, and higher degree of orientation than those of the comparative examples without extremely decreasing HcJ. This is because the Sr ferrite powder having a fine and high ⁇ s obtained by adding Li in advance before calcination is used, so that the sintering is promoted to have such a high density and a high Br. It shows that an Sr ferrite sintered magnet was obtained.
  • the above-mentioned Fe 2 O 3 powder and SrCO 3 powder were mixed while being pulverized for 16 hours using a wet ball mill to obtain a slurry.
  • sodium silicate powder and lithium carbonate powder were added.
  • the addition amount of the sodium silicate powder and the lithium carbonate powder at this time is 0.38% by mass in terms of Na 2 O and Li 2 O, respectively, with respect to the total mass of the Fe 2 O 3 powder and the SrCO 3 powder. It was set to 0.09 mass%.
  • the slurry was spray-dried to obtain a granular mixture having a particle size of about 10 ⁇ m.
  • the mixture was fired in the air at a calcining temperature T 1 (800 to 950 ° C.) shown in Table 6 for 1 hour to obtain a granular calcined body containing Sr ferrite having a hexagonal crystal structure.
  • Example 4-1 to Example 4-6 [Production and Evaluation of Sr Ferrite Sintered Magnet 2] (Example 4-1 to Example 4-6) In the same manner as in Example 3-1 (T 1 : 850 ° C.), a granular calcined body containing Sr ferrite having a hexagonal crystal structure was obtained. Sorbitol, SiO 2 powder and CaCO 3 powder were added to 130 g of this calcined body. The amount of each additive was 1% by mass of sorbitol, 0.4% by mass of SiO 2 powder, and 0.9% by mass of CaCO 3 powder based on the calcined body. After adding these additives, the calcined body was wet-ground using a ball mill to obtain a slurry. Table 8 shows the wet pulverization time and the specific surface area of the Sr ferrite powder by the BET method after the wet pulverization.
  • the present invention it is possible to provide a method for producing an Sr ferrite sintered magnet capable of producing an Sr ferrite sintered magnet having a high Br by a simple process.
  • a sintered Sr ferrite magnet having high magnetic properties and high reliability can be provided.
  • a motor and a generator having high efficiency and high reliability can be provided.

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Abstract

La présente invention concerne un procédé de fabrication d'un aimant fritté en ferrite de Sr, le procédé comprenant : une étape de quasi-frittage pour fritter un mélange qui contient un composé de fer en poudre, un composé de strontium en poudre, et un composé en poudre contenant Li en tant qu'élément constitutif à 850-1050 °C pour obtenir un corps quasi-fritté contenant de la ferrite de Sr ayant une structure cristalline hexagonale et contenant de 0,01 à 0,5 % en masse de Li en termes de Li2O ; une étape de pulvérisation pour pulvériser le corps quasi-fritté pour obtenir une poudre pulvérisée contenant de la ferrite de Sr ; et une étape de frittage pour fritter un corps moulé, obtenu par moulage de la poudre pulvérisée dans un champ magnétique, à 1000-1250 °C pour obtenir l'aimant fritté en ferrite de Sr.
PCT/JP2013/077837 2012-10-11 2013-10-11 Poudre de ferrite de sr, procédé de fabrication d'un aimant fritté en ferrite de sr, moteur et générateur WO2014058067A1 (fr)

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JP2014540917A JPWO2014058067A1 (ja) 2012-10-11 2013-10-11 Ｓｒフェライト粉末及びＳｒフェライト焼結磁石の製造方法、並びにモータ及び発電機

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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPWO2017170427A1 (ja) * 2016-03-31 2019-02-07 パウダーテック株式会社 フェライト粉、樹脂組成物および成形体
TWI706151B (zh) * 2019-08-14 2020-10-01 中國鋼鐵股份有限公司 永磁鐵氧體磁石的磁性評估方法

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CN107473724A (zh) * 2017-07-27 2017-12-15 中钢天源(马鞍山)通力磁材有限公司 一种高性能m型钙锶铁氧体的制备方法及产品
CN107721405B (zh) * 2017-11-16 2020-08-11 安徽鑫磁源磁业有限公司 一种低温煅烧制备M型锶铁氧体SrFe12O19预烧料的方法
CN110323025B (zh) * 2018-03-28 2021-12-10 Tdk株式会社 铁氧体烧结磁铁

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5217694A (en) * 1975-07-31 1977-02-09 Daido Steel Co Ltd Magnet made of sintered oxide
JPS52126795A (en) * 1976-04-17 1977-10-24 Daido Steel Co Ltd Method of manufacturing oxide sintered permanent magnet

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5217694A (en) * 1975-07-31 1977-02-09 Daido Steel Co Ltd Magnet made of sintered oxide
JPS52126795A (en) * 1976-04-17 1977-10-24 Daido Steel Co Ltd Method of manufacturing oxide sintered permanent magnet

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPWO2017170427A1 (ja) * 2016-03-31 2019-02-07 パウダーテック株式会社 フェライト粉、樹脂組成物および成形体
EP3438055A4 (fr) * 2016-03-31 2019-12-04 Powdertech Co., Ltd. Poudre de ferrite, composition de résine, et corps moulé
TWI706151B (zh) * 2019-08-14 2020-10-01 中國鋼鐵股份有限公司 永磁鐵氧體磁石的磁性評估方法

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