JP4710424B2 - Manufacturing method of radial magnetic anisotropic magnet motor - Google Patents

Description

  The present invention relates to a method for manufacturing a radial anisotropic magnet motor, and more particularly to a manufacturing technique for reducing the torque pulsation associated with rotation while increasing the motor output or reducing the thickness while maintaining output characteristics.

The form of Nd ₂ Fe ₁₄ B, αFe / Nd ₂ Fe ₁₄ B, Fe ₃ B / Nd ₂ Fe ₁₄ B magnet material obtained by melt span is limited to ribbons and other flake powders. The For this reason, in order to obtain a generally used bulk permanent magnet, it is necessary to change the material form, that is, a technique for fixing a ribbon or powder to a specific bulk by some method. Although the basic powder fixing means in powder metallurgy is atmospheric pressure sintering, it is difficult to apply atmospheric pressure sintering because the ribbon needs to maintain magnetic properties based on a metastable state. For this reason, fixing to a bulk of a specific shape was performed exclusively with a binder such as an epoxy resin. For example, R.A. W. Lee et al. (B. H) _max 111 kJ / m ³ ribbon fixed with resin (BH) _max 72 kJ / m ³ isotropic Nd ₂ Fe ₁₄ B-based bond magnet [R. W. Lee, E .; G. Brewer, N.M. A. Schaffel, “Hot-pressed Neodymium-Iron-Boron magnets” IEEE Trans. Magn. , Vol. 21, 1958 (1985)] (see Non-Patent Document 1).

In 1986, the present inventors fixed an Nd ₂ Fe ₁₄ B magnet powder obtained by pulverizing the above melt spun ribbon with an epoxy resin according to Japanese Patent Application No. 61-38830 (BH), a small-diameter annular with a _{maximum of} 72 kJ / m ^3. It has been clarified that an isotropic Nd ₂ Fe ₁₄ B bonded magnet is useful for a small motor (see Patent Document 1). Thereafter, T.W. Shimoda also compared the small motor characteristics of the small-diameter annular isotropic Nd ₂ Fe ₁₄ B bond magnet with the small motor characteristics of the Sm—Co radial anisotropic bond magnet, and the former was useful [T. Shimoda, “Compression molding magnet made rapid-quenched powder”, PERMANENT MAGNETS 1988 UPDATE ”, Wheeler Associate INC (1988)] (Non-Patent Document 2).

Furthermore, a report that it is useful for a small motor is disclosed in W.W. Baran ["Case history of NdFeB in the European community", The European Business and Technical Outlook for NdFeB Magnets, Nov. (1989)], G.M. X. Huang, W.H. M.M. Gao, S .; F. Yu ["Application of melt-spun Nd-Fe-B bonded magnet to the micro-motor", Proc. ^{of the 11 th International Rare-Earth} Magnets and Their Applications, Pittsburgh, USA, pp. 583-595 (1990)], Kasai [“MQ1, 2 & 3 magnets applied to motors and actuators”, Polymer Bonded Magnets '92, Embassiy Suite O'Hale 90, 19 Therefore, it has been widely used as an annular magnet for permanent magnet type motors mainly for OA, AV, PC and its peripheral devices and information communication devices (see Non-Patent Documents 3, 4, and 5).

On the other hand, research on magnet materials by melt spinning has been actively conducted since the 1980s,
Microstructure control of various alloy compositions including Nd ₂ Fe ₁₄ B system, Sm ₂ Fe ₁₇ N ₃ system, or nanocomposite materials using exchange coupling based on the microstructure of them with αFe, Fe ₃ B system, etc. In recent years, isai rare earth magnet powders with different powder shapes have become industrially available by rapid solidification methods other than melt spinning, and Kasai [“MQ1, 2 & 3 magnets applied to motors and actors”, Polymer Bonded Magnets '92, Embassiy Suite O'Hare-Rosemont, Illinois, USA, (1992)], B.C. H. Rabin, B.M. M.M. Ma, “Recent developments in Nd—Fe—B powder”, 120 ^th Topical Symposium
of the Magnetic Society of Japan, pp. 23-28 (2001), B.I. M.M. Ma, “Recent powder development at magneque”, Polymer Bonded Magnets 2002, Chicago (2002), S.A. Hirazawa, H .; Kanekiyo, T .; Miyoshi, K .; Murakami, Y .; Shigemoto, T .; Nishiuchi, "Structure and magnetic properties of Nd 2 Fe 14 B / FexB-type nanocomposite permanent magnets prepared by strip casting", 9 th Joint MMM / INTERMAG, CA (2004) FG-05]. There is also a report by Davies et al. That (BH) _max reaches 220 kJ / m ³ while being isotropic [H. A. Davies, J .; I. Betancourt, C.I. L. Harland, “Nanophase Pr and Nd / Pr based rare-earth-iron-boron alloys”, Proc. of 16 ^th Int. Works on Rare-Earth Magnets and Their Applications, Sendai, pp. 485-495 (2000)] (see Non-Patent Documents 6, 7, 8, 9, and 10).

However, (BH) _max of commercially available rapid solidification powder (BH) _max is ~134kJ / m ^3, isotropic Nd ₂ Fe ₁₄ B bond magnet is estimated to approximately 80 kJ / m ^3.

Regardless of the above, the permanent magnet type motors targeted by the present invention are further reduced in thickness, size, output, vibration and noise, or high accuracy in position control under the performance of electric and electronic equipment. There is a constant demand for conversion. Therefore, the improvement of the magnetic characteristics represented by (BH) _max of the magnet powder of the isotropic rare earth bonded magnet is no longer useful for improving the performance of the motor. Therefore, in the field of isotropic rare earth bonded magnet motors, there is an increasing need for application of anisotropic rare earth bonded magnets to permanent magnet motors [Fumitoshi Yamashita, “Application of rare earth magnets to electronic devices. And prospects ”, Ministry of Education, Culture, Sports, Science and Technology Innovation Creation Project / Effective Utilization of Rare Earth Resources and Advanced Materials Symposium, Tokyo, (2002)] (see Non-Patent Document 11)

By the way, the Sm—Co based magnet powder used for the anisotropic rare earth bonded magnet can obtain a large coercive force H _CJ even if the ingot is pulverized. However, Sm and Co have a great resource balance problem, and are not suitable for general use as industrial materials. On the other hand, Nd and Fe are advantageous from the viewpoint of resource balance. However, even if the Nd ₂ Fe ₁₄ B alloy ingot or sintered magnet is pulverized, _HCJ is small. For this reason, with respect to the production of anisotropic Nd ₂ Fe ₁₄ B magnet powder, research using a melt spinning material as a starting material has preceded.

In 1989, Tokunaga pulverized a hot upset (Die-upset) bulk of Nd ₁₄ Fe _80-X B ₆ Ga _X (X = 0.4 to 0.5) and HC _J = 1.52 MA / m Anisotropy Nd ₂ Fe ₁₄ B powder and solidified with resin to obtain an anisotropic bonded magnet with (BH) _max 127 kJ / m ³ [Masaaki Tokunaga, “Magnetic properties of rare earth bonded magnet”, powder and powder Metallurgy, Vol. 35, pp. 3-7, (1988)]. In 1991, H.C. Sakamoto et al. Nd ₁₄ Fe _79.8 B
_5.2 Cu ₁ was hot-rolled to produce anisotropic Nd ₂ Fe ₁₄ B powder of H _CJ 1.30 MA / m [H. Sakamoto, M .; Fujikura and T. Mukai, “Fully-dense Nd-Fe-B magnets prepared from hot-rolled anisotropic powders”, Proc. 11 ^th
Int. Workshop on Rare-earth Magnets and Ther Applications, Pittsburg, pp. 72-84 (1990)]. Thus, to improve the hot workability by the addition of Ga and Cu, the high H _CJ phased powder is known to control the Nd ₂ Fe ₁₄ B crystal grain size (see Non-Patent Document 12).

1991, V.C. Panchanathan et al. Used a hot-working bulk pulverization method to make HD (Hydrogen Depreciation) -Nd ₂ Fe ₁₄ B particles, which were dehydrogenated by vacuum heating by intruding hydrogen from the grain boundaries to collapse into Nd ₂ Fe ₁₄ BH _X , ( BH) An anisotropic bonded magnet with a _{maximum of} 150 kJ / m ³ [M. Doser, V.M. Panchanthan, and R.A. K. Misra, “Pulverizing anisotropy rapidly solidified Nd—Fe—B materials for bonded magnets”, J. Am. Appl. Phys. , Vol. 70, pp. 6603-6805 (1991)] (see Non-Patent Document 14).

In 2001, Iriyama modified Nd _0.137 Fe _0.735 Co _0.067 B _0.055 Ga _0.006 into particles of 310 kJ / m ³ by the same method, and improved it to an anisotropic bonded magnet of (BH) _max 177 kJ / m ³ [T. Iriyama, “Anisotropic bonded NdFeB magnets made from hot-up powders”, Polymer Bonded Magnet 2002, Chicago (2002)] (see Non-Patent Document 15).

Meanwhile, Takeshita et al. Nd—Fe (Co) —B ingot is heat-treated in hydrogen to hydrogenate Nd ₂ (Fe, Co) ₁₄ B phase (Hydrogenation, Nd ₂ [Fe, Co] ₁₄ BHx), 650-1000. The HDDR method is proposed in which phase decomposition (De composition, NdH ₂ + Fe + Fe ₂ B), dehydrogenation, and recombination are performed at ℃ [T. Takeshita, and R.A. Nakayama, "Magnetic properties and micro-structure of the Nd-Fe-B magnet powders produced by hydrogen treatment", Proc. 10 ^th Int. Works on Rare-earth Magnets and Their
Applications, Kyoto, pp. 551-562 (1989)], in 1999, an anisotropic bonded magnet having a (BH) _{max of} 193 kJ / m ³ was produced from HDDR-Nd ₂ Fe ₁₄ B particles (see Non-Patent Documents 16 and 17).

In 2001, Misima et al. Reported Co-free d-HDDR Nd ₂ Fe ₁₄ B particles [C. Misima, N .; Hamada, H .; Mitarai, and Y.M. Honkura, “Development of a Co-free NdFeB anisotropy magnet produced d-HDDR
processes powder ", IEEE Trans. Magn. Vol. 37, pp. 2467-2470 (2001)], N. Hamada et al. (BH) _max 358 kJ / m ³ of the same d-HDDR anisotropic Nd ₂ Fe ₁₄ B Cubic (7 mm x 7 mm x 7 mm) anisotropic bonded magnet with particles compressed at 0.9 GPa in an orientation magnetic field of 150 ° C and 2.5 T at a density of 6.51 Mg / m ³ and (BH) _max 213 kJ / m ³ [N. Hamada, C. Misima, H. Mitarai and Y. Honkura, “Development of anisotrophic bonded magnet with.]
27MGOe "IEEE.Trans.Magn., Vol.39, pp.2953-
2956 (2003)] (see Non-Patent Documents 18 and 19). However, the cubic magnet is not compatible with a general permanent magnet type motor. For example, it is necessary to increase the shape-corresponding force to the permanent magnet type motor as an annular or arc-shaped radial anisotropic magnet having a thickness of about 1 mm.

On the other hand, in 2001, RD (Reduction & Diffusion)-(BH) _max ~ 119 kJ / m ³ injection-molded bonded magnet using fine powder of Sm ₂ Fe ₁₇ N ₃ was reported [Satoshi Kawamoto, Kayo Shiraishi, Kazutoshi Ishizaka, Yasuda. Junichi, “15MGOe-class SmFeN injection molding compound”, Institute of Electrical Engineers of Magnetics, (2001) MAG-01-173]. In 2002, Ohmori reported (BH) _max 323 kJ / m ³ of weathered RD-Sm ₂ Fe ₁₇ N ₃ fine powder (BH) _max 136 kJ / m ³ injection-molded anisotropic magnets. [K. Ohmori, “New era of anisotropic bonded SmFeN magnets”, Polymer Bonded Magnet 2002, Chicago (2002)]. By using a surface magnet (SPM) rotor to which such an anisotropic Sm ₂ Fe ₁₇ N ₃ bonded magnet with an injection molding radial anisotropy (BH) _{max of} 80 kJ / m ³ is used, a ferrite sintered magnet motor is used. There is also a report that achieved high efficiency [Atsushi Matsuoka, Togo Yamazaki, Hitoshi Kawaguchi, “Examination of high performance brushless DC motor for blower”, IEEJ rotating machine workshop, (2001) RM-01-161] . (Refer nonpatent literature 20, 21, and 22).

However, in the radial orientation magnetic field, when the mold ring cavity is reduced in diameter (or lengthened), most of the magnetomotive force is consumed as the leakage magnetic flux, so that the orientation magnetic field is reduced. Therefore, as the degree of orientation decreases, the (BH) _max decreases as the diameter decreases regardless of the bond magnet or sintered magnet [for example, Motoharu Shimizu, Nobuyuki Hirai, “Nd—Fe—B based sintering” Type anisotropic ring magnet ", Hitachi Metals Technical Report, Vol. 6, pp. 33-36 (1990)]. In addition, it is difficult to generate a homogeneous radial magnetic field, and there is a problem that productivity is low compared to isotropic bonded magnets (see Non-Patent Document 23).

However, if the magnetic properties in the radial direction do not depend on the shape, uniform orientation is possible, and high productivity can be realized, a high (BH) _max radial magnetic anisotropic magnet useful for improving the performance of permanent magnet motors. Is expected to spread. Therefore, the present inventors compression-molded a compound of a binder and magnet powder, mechanically stretched the macromolecules between crosslinks of the binder formed after self-assembly, Disclosed is a technique for producing a radial magnetic anisotropy magnet that controls flexibility and uses the flexibility to change the direction of magnetic anisotropy to the radial direction [F. Yamashita, S .; Tsusumumi, H .; Fukunaga, “Radially Anisotropic Ring-or Arc-Shaped Rare-Earth Bonded Magnets Using Self-Organization Technique”, IEEE Trans. Magn. , Vol. 40, no. 4 pp. 2059-2064 (2004)]. This makes it possible to manufacture a radial magnetic anisotropic magnet in which the radial magnetic characteristics hardly deteriorate even when the diameter is reduced (or lengthened). (Refer nonpatent literature 24).
JP-A-62-196057 R. W. Lee, E .; G. Brewer, N.M. A. Schaffel, “Hot-pressed Neodymium-Iron-Boron magnets” IEEE Trans. Magn. , Vol. 21, 1958 (1985) T.A. Shimoda, “Compression molding magnet made rapid-quenched powder”, PERMANENT MAGNETS 1988 UPDATE ”, Wheeler Associate INC (1988) W. Baran “Case history of NdFeB in the European community”, The European Business and Technical Outlook for NdFeB Magnets, Nov. (1989) G. X. Huang, W.H. M.M. Gao, S .; F. Yu "Application of melt-spun Nd-Fe-B bonded magnet to the micro-motor", Proc. of the 11th International Rare-Earth Magnets and Their Applications, Pittsburgh, USA, pp. 583-595 (1990) Kasai “MQ1, 2 & 3 magnets applied to motors and actors”, Polymer Bonded Magnets '92, Embassiy Suite O'Hare-Rosemont, Illinois, USA (USA), 19 Kasai “MQ1, 2 & 3 magnets applied to motors and actors”, Polymer Bonded Magnets '92, Embassiy Suite O'Hare-Rosemont, Illinois, USA (USA), 19 B. H. Rabin, B.M. M.M. Ma, “Recent developments in Nd—Fe—B powder”, 120th Topical Symposium of the Magnetic Society of Japan, pp. 23-28 (2001) B. M.M. Ma, “Recent powder development at magneque”, Polymer Bonded Magnets 2002, Chicago (2002) S. Hirazawa, H .; Kanekiyo, T .; Miyoshi, K .; Murakami, Y .; Shigemoto, T .; Nishiuchi, “Structure and magnetic properties of Nd2Fe14B / FexB-type nanocomposite permanent magnets pre-prepared by MMM” 5G H. A. Davies, J .; I. Betancourt, C.I. L. Harland, “Nanophase Pr and Nd / Pr based rare-earth-iron-boron alloys”, Proc. of 16th Int. Works on Rare-Earth Magnets and Their Applications, Sendai, pp. 485-495 (2000) Fumitoshi Yamashita, “Application and Prospect of Rare Earth Magnets for Electronic Equipment”, Ministry of Education, Culture, Sports, Science and Technology Innovation Creation Project / Effective Utilization of Rare Earth Resources and Advanced Materials Symposium, Tokyo, (2002) Masaaki Tokunaga, “Magnetic Properties of Rare Earth Bond Magnets”, Powder and Powder Metallurgy, Vol. 35, pp. 3-7, (1988) H. Sakamoto, M .; Fujikura and T. Mukai, “Fully-dense Nd-Fe-B magnets prepared from hot-rolled anisotropic powders”, Proc. 11th Int. Workshop on Rare-earth Magnets and Ther Applications, Pittsburg, pp. 72-84 (1990) M.M. Doser, V.M. Panchanthan, and R.A. K. Misra, “Pulverizing anisotropy rapidly solidified Nd—Fe—B materials for bonded magnets”, J. Am. Appl. Phys. , Vol. 70, pp. 6603-6805 (1991) T.A. Iriyama, “Anisotropic bonded NdFeB magnets made from hot-upset powders”, Polymer Bonded Magnet 2002, Chicago (2002) T.A. Takeshita, and R.A. Nakayama, "Magnetic properties and micro-structure of the Nd-Fe-B magnet powders produced by hydrogen treatment", Proc. 10th Int. Works on Rare-earth Magnets and Ther Applications, Kyoto, pp. 551-562 (1989) K. Morimoto, R.A. Nakayama, K .; Mori, K .; Igarashi, Y. et al. Ishii, M .; Itakura, N .; Kuwano, K .; Oki, “Nd 2 Fe 14 B-based magnetic powder with high remanufactured produced by modified HDDR process”, IEEE. Trans. Magn. , Vol. 35, pp. 3253-3255 (1999) C. Misima, N .; Hamada, H .; Mitarai, and Y.M. Honkura, “Development of a Co-free NdFeB anisotropy magnet produced produced d-HDDR processes powder”, IEEE. Trans. Magn. Vol. 37, pp. 2467-2470 (2001) N. Hamada, C.I. Misima, H .; Mitarai and Y.M. Honkura, “Development of anisotrophic bonded with 27 MGOe” IEEE. Trans. Magn. , Vol. 39, pp. 2953-2956 (2003) Satoshi Kawamoto, Kayo Shiraishi, Kazutoshi Ishizaka, Junichi Yasuda, “15MGOe-class SmFeN injection molding compound”, The Institute of Electrical Engineers of Japan, (2001) MAG-01-173 K. Ohmori, “New era of anisotropic bonded SmFeN magnets”, Polymer Bonded Magnet 2002, Chicago (2002) Atsushi Matsuoka, Togo Yamazaki, Hitoshi Kawaguchi, “Examination of high performance brushless DC motor for blower”, The Institute of Electrical Engineers of Japan, (2001) RM-01-161 Motoharu Shimizu, Nobuyuki Hirai, “Nd—Fe—B sintered anisotropic ring magnet”, Hitachi Metals, Vol. 6, pp. 33-36 (1990) F. Yamashita, S .; Tsusumumi, H .; Fukunaga, “Radially Anisotropic Ring-or Arc-Shaped Rare-Earth Bonded Magnets Using Self-Organization Technique”, IEEE Trans. Magn. , Vol. 40, no. 4 pp. 2059-2064 (2004)

For example, a thin plate-like anisotropic rare earth bonded magnet having a self-organized binder (BH) _max = 162 kJ / m ³ and a thickness of 0.97 mm is anisotropically stretched to have an inner radius of 3.55 mm, The outer radius is 3.65 mm, the maximum thickness is 0.88 mm, and the length is 10 mm. When this magnet is magnetized with a pulse magnetic field of 4 MA / m, the magnetic flux is 1.53 times the amount of magnetic flux of an isotropic Nd ₂ Fe ₁₄ B bond magnet of (BH) _max 72 kJ / m ³ , which is a permanent magnet type. Increase the starting torque of the motor by 1.4 times or more. However, there is a drawback that the torque pulsation accompanying the rotation of the motor increases 15 times or more.

If the magnet shape and the configuration of the magnetic circuit including the iron core are the same, the gap magnetic flux density between the iron core and the magnet is approximately proportional to the square root of the ratio of (BH) _max of the magnet, so isotropic Nd ₂ Fe _14. It is possible to increase the output of a permanent magnet type motor using a B bond magnet, or to reduce the thickness and weight. However, a high (BH) _max radial magnetic anisotropic magnet motor undergoes a magnetization reversal of approximately 180 degrees between multipole magnetized magnetic poles. Therefore, the air gap magnetic flux density distribution between the iron core and the magnet is rectangular.

On the other hand, the isotropic Nd ₂ Fe ₁₄ B bond magnet to be compared in the present invention has a magnetization pattern in which magnetization is concentrated at the center of each magnetic pole of the multipolar magnetized ring magnet when multipolar magnetization is performed. In between, the magnetization component in the in-plane direction is increased instead of the radial magnetization. For this reason, the gap magnetic flux density distribution between the iron core and the magnet has a pseudo sine wave shape.

As described above, the radial magnetic anisotropic magnet motor is expected to be about 1.4 times higher in output and 30% thinner and lighter than the isotropic Nd ₂ Fe ₁₄ B bonded magnet motor, but strong. The static magnetic field and the rectangular wave-shaped gap magnetic flux density distribution inevitably increase the torque pulsation accompanying the rotation of the motor. Torque pulsation requires a tooth and a slot in the iron core on the surface facing the magnet because of the structure of the motor combined with the stator on which the electromagnetic winding is arranged on the outer peripheral surface of the iron core facing the magnet. For this reason, it is a torque pulsation for the permeance coefficient Pc to inevitably change as the motor rotates. In addition, in the arc-shaped magnet as described above, 1) the radius of curvature of the inner and outer circumferences of the magnet is decentered so that the thickness between the magnetic pole center and the magnetic pole is unequal. 2) By changing the shape of the magnet (permeance), for example, by reducing the corners of the circumferential end corresponding to the gap between the magnetic poles of the magnet, the gap magnetic flux density distribution between the iron core and the arc-shaped magnet is made sinusoidal. It is possible to approach. (For example, Shun Zhong, “Application of permanent magnets in small motors”, Proceedings of Small Motor Technology Symposium, p7, 1983).

However, when multipolar magnetization is applied to an annular magnet, it is often difficult to accurately change the magnet shape (permeance) by means of grinding such as an arc magnet. Therefore, it is common to skew either the iron core or the magnetic pole of the magnet on an axial basis. However, when the axial distance of the iron core or magnet is reduced to, for example, about 1 mm, the skew based on the axial direction becomes difficult. That is, a high (BH) _max radial magnetic anisotropic magnet motor can be thinned in terms of output, but the gap magnetic flux density between the iron core and the magnet can be reduced by combining conventional techniques such as magnet thinning and magnetic pole skew. It becomes substantially difficult to approximate the sine wave.
The present invention maintains a high (BH) max, discloses a technique for changing the direction of anisotropy of a perpendicular magnetic anisotropic thin plate magnet to a radial direction, and a specific condition for controlling the orientation between magnetic poles. By maintaining the strength of the static magnetic field in the gap between the generated iron core and the motor, the deterioration of the output characteristics of the motor is suppressed. In addition, the object is to provide a radial magnetic anisotropic magnet motor that can reduce the torque pulsation by reducing the gap magnetic flux density distribution between the iron core and the magnet to a sinusoidal shape and suppress the low vibration noise or the decrease in position control accuracy. To do. In particular, iron cores and magnets are difficult to achieve by combining conventional techniques, such as making magnets thinner and providing magnetic pole skew, such as spindle motors for various recording media that are desired to be thin while maintaining output characteristics. It is possible to make the gap magnetic flux density close to a sine wave shape.

In the present invention, assuming that the maximum magnetization in the vertical direction is Mmax⊥ and the maximum magnetization in the in-plane direction is Mmax //, there is no difference in the mother dispersion and the population mean of Mmax⊥ / Mmax // before and after rolling with a probability of 95%. A perpendicular magnetic anisotropic thin plate magnet is used. In particular, when Mmax⊥ / Mmax // is 1.45 or more, the coercivity in the vertical direction is HcJ⊥, and the coercivity in the in-plane direction is HcJ //, HcJ⊥.
This is a method for manufacturing a radial magnetic anisotropic magnet motor, in which a perpendicular magnetic anisotropic thin plate magnet rolled under the condition of / HcJ // is 0.90 ± 0.01 and the direction of the anisotropy is changed to the radial direction. .

  A more preferable form is a radial magnetic anisotropy that changes the anisotropy direction of the perpendicular magnetic anisotropic thin plate magnet in which Mmax / Mmax // between the magnetic poles is smaller than Mmax / Mmax // between the magnetic pole centers. It is a manufacturing method of a direction magnet motor.

More preferably, the thickness of the magnet at the center of the magnetic pole is 1.35 mm or less, and the magnetic powder is mixed with the single domain particle type Sm ₂ Fe ₁₇ N ₃ fine powder and the polycrystalline aggregated Nd ₂ Fe ₁₄ B particles ( BH) A radial magnetic anisotropic magnet motor manufacturing method in which _max is 140 kJ / m ³ or more. As a result, motor torque pulsation is suppressed along with high (BH) _{max, making} it thinner, smaller, and higher output, reducing motor thickness, size, higher output, lower vibration noise, and improving position controllability. It can correspond to.

  In the present invention, a perpendicular magnetic anisotropic thin plate magnet produced by compression molding a compound of a binder and magnet powder is self-assembled to form a macromolecular chain between crosslinks. When the maximum magnetization in the vertical direction is Mmax⊥ and the maximum magnetization in the in-plane direction is Mmax //, there is a 95% probability that there is no difference in the mother dispersion of Mmax 母 / Mmax // before and after rolling and the population average. A magnetic anisotropic thin plate magnet is used. Further, when Mmax⊥ / Mmax // is 1.45 or more, the coercive force in the vertical direction is HcJ⊥, and the coercivity in the in-plane direction is HcJ //, HcJ⊥ / HcJ // is 0.90 ± 0. This is a method of manufacturing a radial magnetic anisotropic magnet motor which is a perpendicular magnetic anisotropic thin plate magnet rolled at .01 and multi-pole magnetization is performed by changing the direction of anisotropy to the radial direction.

  In a more preferred embodiment, the direction of anisotropy of a perpendicular magnetic anisotropic thin plate magnet in which Mmax / Mmax // between magnetic poles is smaller than Mmax / Mmax // at the magnetic pole center is changed to a radial direction. This is a method of manufacturing a magnetized radial magnetic anisotropic magnet motor.

More preferably, the thickness of the magnet at the center of the magnetic pole is 1.35 mm or less, and the magnet powder is a mixture of single domain particle type Sm ₂ Fe ₁₇ N ₃ fine powder and polycrystalline aggregated Nd ₂ Fe ₁₄ B particles. This is a radial magnetic anisotropic magnet motor in which (BH) _max of a magnetic pole portion of a magnet including molecules is 140 kJ / m ³ or more. This suppresses the torque pulsation of a radial magnetic anisotropic magnet motor that can be thinned, miniaturized and increased in output at a high (BH) _max , making the motor thinner, smaller, higher output, and less vibration noise. And improved position controllability.

  First, the anisotropic rare earth magnet powder suitable for the magnet according to the present invention will be described.

The polycrystalline aggregated Nd ₂ Fe ₁₄ B particles referred to in the present invention are HDDR treatment (hydrogen decomposition / recombination), that is, hydrogenation of a rare earth-iron alloy (R ₂ [Fe, Co] ₁₄ B) phase. , R ₂ [Fe, Co] ₁₄ BHx), phase decomposition at 650 to 1000 ° C. (Decomposition, RH ₂ + Fe + Fe ₂ B), dehydrogenation (desorption), recombination (recombination), and so-called HDDR treatment. Say magnet powder.

If the essential element R is less than 10 atomic%, the crystal structure has the same cubic structure as that of α-Fe. Therefore, high magnetic properties, particularly high coercive force H _CJ cannot be obtained. The rich nonmagnetic phase increases and the saturation magnetization Js decreases. Therefore, R is preferably in the range of 10 to 30 atomic%. In addition, when the essential element B is less than 2 atomic%, the rhombohedral structure becomes the main phase, and a high coercive force H _CJ cannot be obtained, and when it exceeds 28 atomic%, the B-rich nonmagnetic phase increases and the saturation magnetization Js is increased. descend. Therefore, B is preferably in the range of 2 to 28 atomic%.

On the other hand, if the essential element Fe is less than 65 atomic%, the saturation magnetization Js decreases, and if it exceeds 80 atomic%, a high coercive force H _CJ cannot be obtained. Therefore, the Fe content is desirably 65 to 80 atomic%. Further, replacing part of Fe with Co can improve the temperature coefficient of the residual magnetization Jr in the actual operating temperature range by increasing the Curie temperature Tc without impairing the magnetic properties of the magnet powder. However, the saturation magnetization Js decreases when the Fe substitution amount of Co exceeds 20 atomic%. That is, when the Co substitution amount is in the range of 5 to 15 atomic%, the residual magnetization Jr generally increases, which is preferable for obtaining a high (BH) _max .

  On the other hand, in addition to R, B and Fe, the presence of impurities unavoidable for industrial production is acceptable. For example, it is a general allowable range that a part of B is 4 wt% or less of C, or at least one of P, S, and Cu, and the total amount is 2 wt% or less.

Furthermore, at least one of Al, Ti, V, Cr, Mn, Bi, Nb, Ta, Mo, W, Sb, Ge, Ga, Sn, Zr, Ni, Si, Zn, and Hf is a powder holding agent. It can be added as appropriate in order to improve the magnetic force H _CJ and the squareness Hk / H _CJ of the demagnetization curve. The rare earth element R occupying 10 atomic% to 30 atomic% of the composition is at least one of Nd, Pr, Dy, Ho, and Tb, or La, Ce, Sm, Gd, Er, Eu, Tm, At least one of Yb, Lu, and Y is included. Usually, one kind of R is sufficient, but in practice, a mixture of two or more kinds (Misch metal, shijim, etc.) can also be used. In addition, this R can contain impurities unavoidable in production within a commercially available range.

Next, the single domain particle type Sm ₂ Fe ₁₇ N ₃ fine powder referred to in the present invention is, for example, a melt casting method described in JP-A-2-57663, Japanese Patent No. 17025441 or JP-A-9-157803. An R—Fe-based alloy or an R— (Fe, Co) -based alloy is produced by a reduction diffusion method disclosed in a gazette or the like, nitrided, and finely pulverized. The fine pulverization refers to a finely pulverized product such as a jet mill, a vibrating ball mill, a rotating ball mill, etc., which is finely pulverized so as to have a Fisher average particle size of 1.5 μm or less, preferably 1.2 μm or less. In order to improve handling properties such as prevention of ignition, fine powders are disclosed in, for example, JP-A-52-54998, JP-A-59-170201, JP-A-60-128202, JP-A-3-211203. As described in JP-A-46-7153, JP-A-56-55503, JP-A-61-154112, JP-A-3-126801, etc. What formed the oxide film on the surface is desirable. In addition, JP-A-5-230501, JP-A-5-234729, JP-A-8-143913, JP-A-7-268632, and the outline of the presentation of the Japan Institute of Metals (Spring convention 1996, No. 446, p184) and the like, a method of forming a metal film, JP-B-6-17015, JP-A-1-234502, JP-A-4-217024, JP-A-5-213601, One or more kinds of surface-treated Sm ₂ Fe ₁₇ N ₃ fine powder may be used, such as a method of forming an inorganic film according to 7-326508, JP-A-8-153613, JP-A-8-183601, or the like. Absent.

  Next, formation of a macromolecule between crosslinks will be described with reference to the conceptual diagram of the molecular structure in FIG. In the figure, A is an oligomer as a magnet powder fixing component, for example, a novolak type epoxy having an epoxy equivalent of 205 to 220 g / eq and a melting point of 70 to 76 ° C. B is a linear polymer forming the macromolecule D between crosslinks, for example, a polyamide having a melting point of 80 ° C. and a molecular weight of 4000 to 12000. C is a chemical contact, for example, an imidazole derivative having a melting point of 80 to 100 ° C.

In the present invention, for example, 38 parts by weight of single domain particle type Sm ₂ Fe ₁₇ N ₃ fine powder and 57 parts by weight of polycrystalline aggregated Nd ₂ Fe ₁₄ B particles are coated with 1 part by weight of oligomer A. After melt-kneading with polymer B at 120-130 ° C., cooling to room temperature and coarsely pulverizing, filling compound mixed with 0.28 parts by weight of chemical contact C into a mold cavity at 160 ° C., 1.5 MA / m In the above parallel magnetic field, compression-molding is performed at 50 MPa, and a perpendicular magnetic anisotropic thin plate magnet having a thickness of 1.35 mm or less including the inter-crosslinking macromolecule D is produced by heat treatment at 150 ° C. for about 20 minutes.

  The tensile strength at 20 ° C before heat treatment of compression molded thickness 1.15mm x width 6mm x length 60mm is about 1.8MPa, but when the heat temperature exceeds 120 ° C when heat treated for 20min, A crosslinking reaction occurs between oligomer A and polymer B centering on C, and the tensile strength at room temperature starts to increase. And it exceeds 9 MPa at 150 ° C., and saturates at about 9.5 MPa at 160-200 ° C. Thus, the tensile strength of the magnet reaches 5 times or more of that before the heat treatment by the optimized heat treatment. In this example, there is also a direct reaction between the epoxy group of oligomer A and the amino active hydrogen (-NHCO-) of polymer B, but the main reaction appears to be the amino active hydrogen of chemical contact C (imidazole derivative).

  By the crosslinking reaction, the binder has a three-dimensional network structure. In particular, the oligomer A firmly adheres and fixes the magnet powder with its polarity and high crosslink density. Also, one polymer B forms a macromolecule D between crosslinks. The thin plate magnet can be rolled by including the inter-crosslinking macromolecule D in the thin plate magnet. In addition, the stretching of the inter-crosslinking macromolecules D by rolling becomes a flexible carrier of the thin plate magnet, and the anisotropic direction can be changed to the radial direction.

  In the above magnet, in the present invention, when the maximum magnetization in the vertical direction is Mmax 内 and the maximum magnetization in the in-plane direction is Mmax //, the mother dispersion of Mmax⊥ / Mmax // before and after rolling and the probability of 95% in the mother average When there is no difference and their Mmax / Mmax // is 1.45 or more, the coercivity in the vertical direction is HcJｃ, and the coercivity in the in-plane direction is HcJ //, HcJ⊥ / HcJ / before and after rolling / Is 0.90 ± 0.01.

  The present invention is a method of manufacturing a radial magnetic anisotropic magnet motor that changes the direction of anisotropy of a perpendicular magnetic anisotropic thin plate magnet rolled as described above to a radial direction.

  As a more preferable magnet configuration in the present invention, the magnetic anisotropy direction of the perpendicular magnetic anisotropic thin plate magnet in which Mmax / Mmax // between the magnetic poles is smaller than Mmax / Mmax // at the magnetic pole center is changed to the radial direction. This is a method of manufacturing a radial magnetic anisotropic magnet motor.

This suppresses torque pulsation of the motor that can be thinned, downsized, and increased in output power at a high (BH) _max , making the motor thinner, downsized, increased output, reduced vibration noise, and position controllability. It can cope with improvement.

  Hereinafter, the present invention will be described in more detail with reference to examples. However, the present invention is not limited to the examples.

[1. Fabrication of perpendicular anisotropic thin plate magnet]
Single domain particle type Sm ₂ Fe ₁₇ N ₃ fine powder 38.20 parts by weight, polycrystalline aggregated Nd ₂ Fe ₁₄ B particles 57.44 parts by weight, 1 part by weight of oligomer A, and polymer at 120 to 130 ° C. After melt kneading with B, the mixture is cooled to room temperature and coarsely pulverized, and a compound mixed with 0.28 parts by weight of chemical contact C is filled into a 160 ° C. mold cavity, and in a parallel magnetic field of 1.5 MA / m or more, A perpendicular magnetic anisotropic thin plate magnet having a thickness of 1.3 mm or less including a macromolecular chain D between crosslinks was produced by compression molding at 50 MPa and heat treatment at 150 ° C. for about 20 minutes. In addition,
The obtained magnet had a tensile strength at room temperature of 9.2 MPa.

However, the polycrystalline aggregated Nd ₂ Fe ₁₄ B particles are HDDR-treated particles having an alloy composition of Nd _12.3 Dy _0.3 Fe _64.7 Co _12.3 B _6.0 Ga _0.6 Zr _0.1 , and oligomer A has an epoxy equivalent of 205 to 220 g / eq, melting point of 70 to 76 ° C. Polyglycidyl ether-o-cresol novolak type epoxy, polymer B has a melting point of 80 ° C., acid value of 10 or less, amine value of 20 or less, and polyamide powder having a molecular weight of 4000 to 12000, chemical contact C has an average particle diameter of 3 μm, melting point of 80 It is an imidazole derivative at −100 ° C.

[2. Magnetic properties of perpendicular magnetic anisotropic thin plate magnets]
In FIG. 2, a magnet (sample shape 8 × 3.5 × 8 mm, permeance coefficient Pc≈5.36) is pulse magnetized at 4 MA / m, and a demagnetizing field coefficient N is set to 0 using a sample vibration magnetometer (VSM). .157 shows the temperature dependence of the demagnetization curve after demagnetizing field correction. As shown in the figure, the room temperature demagnetization curves of the Sm ₂ Fe ₁₇ N ₃ / Nd ₂ Fe ₁₄ B and Nd ₂ Fe ₁₄ B bonded magnets almost coincide from the residual magnetization Jr to around B / μ ₀ H = 1. (BH) max was approximately 160 kJ / m ³ . However, the squareness (Hk / HcJ) of the demagnetization curve varies as the temperature rises, and Sm ₂ Fe ₁₇ N ₃ / Nd ₂ Fe ₁₄ B has a lower Hk / HcJ than the Nd ₂ Fe ₁₄ B magnet. Few.

FIG. 3 shows a fracture surface of a magnet molded at 50 MPa. Nd ₂ Fe ₁₄ B particles are isolated by Sm ₂ Fe ₁₇ N ₃ fine powder, and crushing and surface damage during molding of Nd ₂ Fe ₁₄ B particles are suppressed, so the Hk of the demagnetization curve at high temperature / HcJ improves. In addition, in the Sm ₂ Fe ₁₇ N ₃ / Nd ₂ Fe ₁₄ B bonded magnet molded at 1.5 GPa, no improvement in Hk is observed due to the influence of the new surface and surface defects caused by the crushing of the Nd ₂ Fe ₁₄ B particles (K. Noguchi). , K. Machida, G. Adachi, “Preparation and characterization of composite-type bonded magnets of Sm ₂ Fe ₁₇ Nx and Nd-Fe-B HDDR powers, Proc.
Applications, pp. 845-854, 2000).

FIG. 4 shows the relationship between (BH) max and the density of 400- 1350 μm thick thin plate magnets manufactured under the same conditions as the 1029 μm thick perpendicular magnetic anisotropic thin plate magnet used in this experiment. However, in the figure, 1 is a standard composition thin plate magnet containing the additive PESTE, and 2 does not contain PESTE. Reference numeral ³ denotes a Sm ₂ Fe ₁₇ N ₃ injection-molded bonded magnet having a thickness of 350 μm, a density of 4.79 Mg / m ³ and a (BH) max of 94.7 kJ / m ³ as a comparison. (K. Ohmori, S. Hayashi, S. Yoshizawa, “Injection molded Sm-Fe-Nanitropic magnets using unsaturated polyresin”, Proc. Rare-Earths'04.
in NARA, (2004) JO-02) As compared with the Sm ₂ Fe ₁₇ N ₃ injection-molded bonded magnet 3, the density of the thin plate magnets 1 and 2 containing Nd ₂ Fe ₁₄ B particles is higher. Further, the density of 1 is stable at 5.72-5.94 Mg / m ³ as compared with the thin plate magnet 2, and the minimum thickness can be made up to 400 μm, which is 1/2 of the thin plate magnet 2. Further, when (BH) max is compared at the same density, the value of the standard composition thin plate magnet 1 is approximately 10 kJ / m ³ higher than 2. This is because when the molding process is performed in an axial magnetic field (1.4 MA / m), the apparent melt viscosity increases when a velocity gradient occurs during melt flow as shown in FIG. Shear stress occurs between them. This shear stress is thought to hinder thinning and orientation. The standard composition thin plate magnet 1 becomes a melt flow with slipping as shown in FIG. 5 (a) due to the external sliding action of the non-polar long chain aliphatic hydrocarbon of the additive PESTE (F. Yamashita, H. Fukunaga: “Anisotropic”). rare-earth thin bonded magnets prepared by compacting using slip-flow phenomenon ", IEEE Trans. Magn., vol. 41, (in press
).

The above effect is due to Ga (M. Tokunaga, N. Nozawa, K. Iwasaki, M. Endoh, S. Tanigawa, and H. Harada, "Ga added Nd-Fe-B sintered and died in Die-upset Nd ₂ Fe ₁₄ B. -Up set magnets ", IEEE Trans. Magn., Vol. 25, pp. 3561-3566, (1989) .26), Cu (T. Mukai, Y. Okazaki, H. Sakamoto, M. Fujikura, and T.-M. Inaguma, “Fully-dense Nd-Fe-B magnets prepared from hot-rolled anisotropic powders,” Proc. 11th Int. Workshop. RE Magnets and Their Applications, workability present magnet similar to the improvement of by the addition of pp.72-84 (1990)) is effective in orienting and thinning.

[3. Anisotropy change due to rolling]
FIG. 6 shows the rolling of a magnet according to the present invention. In the figure, 1 is a constant-speed rolling roll having a diameter of 90 mm, 2 is a state in which a macromolecule between crosslinks contained in the magnet is uniaxially stretched by rolling, and 3 is a direction of anisotropy of the magnet by utilizing flexibility generated in the stretching direction Shows a state in which the vertical direction is changed from the vertical direction to the radial direction, and a reduction ratio of 3 to 5% is required to develop such flexibility.

  FIG. 7 shows a result of normalizing a change in magnetic flux when a magnet having a thickness of 0.85 to 2.50 mm is pulse-magnetized in advance at 4 MA / m and rolled at 80 ° C. with reference to a magnetic flux of 2.5 mm before rolling. Show. In the figure, symbol □ indicates the magnetic flux before rolling, and ○ indicates the magnetic flux after rolling. Moreover, the curve in a figure has shown the thickness dependence of the magnetic flux before rolling. When the magnetic flux of a magnet having a thickness of 2.1 to 2.5 mm is compared with a curve indicating the magnetic flux before rolling, a remarkable reduction in magnetic flux is observed. This is presumed to be a disorder in the orientation of the magnet powder due to rolling. On the other hand, the magnetic flux before and after rolling substantially matches in the thickness range of 0.85 to 1.35 mm.

By the way, the thickness of the isotropic Nd ₂ Fe ₁₄ B bond magnet used in the small motor is about 1 mm. Accordingly, FIG. 8 shows an example of the MH loop when a perpendicular magnetic anisotropic thin plate magnet having a thickness of about 1029 μm is rolled to a thickness of about 830 μm (a reduction rate of 0 to 20%). However, the reduction rate of the magnet (5 mm × 5 mm) is 7 levels, the number of samples n of each level is 5, and the MH loops in the vertical and in-plane directions of all the samples are set to VSM (maximum measurement magnetic field Hm = 2.2. 4 MA / m). In FIG. 8, the decrease in the vertical magnetization M⊥ and the in-plane magnetization M // seen in the vicinity of the maximum measurement magnetic field Hm is due to the mirror effect. The MH loop is not demagnetized.

  Table 1 shows a reduction ratio of 7 levels, n = 5 coercivity HcJ⊥ in the vertical direction obtained from all MH loops at each level, coercivity HcJ // in the in-plane direction, maximum magnetization Mmax⊥ in the vertical direction, surface The maximum magnetization Mmax // in the inner direction is shown collectively.

  Next, in order to clarify the anisotropy change of the perpendicular magnetic anisotropic thin plate magnet by rolling, first, the maximum magnetization Mmax⊥ in the vertical direction and the maximum magnetization Mmax // in the in-plane direction, Mmax⊥ / Mmax // was evaluated. However, since the standard Ni of the same shape as the sample is necessary for correcting the mirror effect of magnetization, the value of Mmax⊥ / Mmax // here is the magnetization in the maximum magnetic field before the occurrence of the mirror effect of FIG. .

  FIG. 9 shows the reduction rate dependence of Mmax / Mmax //. A magnetically isotropic magnet is strongly influenced by a demagnetizing field in the direction perpendicular to the surface. Therefore, Mmax / Mmax // = 0.9 in the state without demagnetizing correction as in this experiment. Therefore, if MmaxＭ / Mmax // is 0.9 or more, it is anisotropic in the vertical direction. Moreover, it means that the anisotropy in the vertical direction increases as the value of Mmax / Mmax // increases. As shown in the figure, in this experiment, the average value of Mmax / Mmax // is 1.45 or more even for a sample with a reduction ratio of 0%, but the value decreases as the reduction ratio increases. However, as shown in FIG. 6 and 3 in the figure, a rolling reduction of about 3 to 5% may be used to change the anisotropic direction from the perpendicular to the radial direction by utilizing the flexibility in the stretching direction.

  Therefore, when the difference between the population variance and the population mean of Mmax⊥ / Mmax // with a reduction rate of 0 and 5.11% shown in Table 1 is tested, Fo = 4.83 <F (4,4; 0.025 ) = 9.60, to = 0.679 <t (8,0.10) = 1.860, the risk is 5%, there is no difference between them, and the anisotropy does not change. Further, when the difference between the population variance and the population mean of Mmax ／/ Mmax // with a rolling reduction of 0 and 7.21% is tested, Fo = 1.708 <F (4,4; 0.025) = 9.60. To = 4.078> t (8,0.10) = 1.860, and there is no difference in population variance at a risk rate of 5%, but there is a difference in population mean. Furthermore, it became clear that the anisotropy changed as the rolling reduction increased.

  Subsequently, in the case of a perpendicular anisotropic thin plate magnet as in this experiment, when the coercive force in the vertical direction is HcJ 内 and the coercive force in the in-plane direction is HcJ //, as apparent from the MH loop shown in FIG. , HcJ⊥ ≦ HcJ //. Therefore, HcJ⊥ / HcJ // was evaluated.

  FIG. 10 shows the reduction rate dependency of HcJＨ / HcJ //. HcJ /// HcJ⊥ is 1 in a magnetically isotropic magnet regardless of the influence of the demagnetizing field. However, in this experiment, the average value of HcJ⊥ / HcJ // was 0.90 ± 0.01 in the range of 0-15%, and a tendency toward 1 was observed when the reduction rate exceeded 15%. .

  As described above, in order to change the anisotropy direction of the rigid thin plate magnet from the plane perpendicular to the radial direction, a rolling reduction of 3-5% is required. However, the degree of anisotropy as shown in FIG. Flexibility can be controlled while maintaining Further, when assuming multipolar magnetization, by setting the rolling reduction ratio of the portion between the magnetic poles to 15% or more, only the portion of the magnetic pole that is magnetically close to isotropic as shown in the conceptual diagram of FIG. It is also possible to control the orientation between. In addition, since the gap distance between the magnetic poles and the iron core is increased, the magnetic flux density distribution between the radial anisotropic magnet and the iron core can be made close to a sine wave.

  Therefore, it is possible to reduce the torque pulsation accompanying rotation while increasing the output of the motor or reducing the thickness while maintaining the output characteristics. Although the present radial magnetic anisotropic magnet motor is magnetized with multiple poles, the magnetization may be performed before or after the direction of anisotropy is changed to the radial direction.

  The method for manufacturing a radial magnetic anisotropic magnet motor according to the present invention is useful for making the motor thinner, smaller, higher output, lower vibration noise, and improving position controllability.

Conceptual diagram of molecular structure of macromolecular chain between crosslinks Characteristic diagram showing demagnetization curve of bulk magnet Broken section of perpendicular magnetic anisotropic thin plate magnet Characteristic diagram showing the relationship between the density of thin magnets and (BH) max Conceptual diagram of melt flow with slip External view showing rolling Characteristic diagram showing the relationship between magnet thickness and magnetic flux before and after rolling Characteristic chart showing MH curves in the vertical direction before and after rolling and in the in-plane direction Characteristic diagram showing the ratio of the maximum magnetization Mmax⊥ in the vertical direction and the maximum magnetization Mmax // in the in-plane direction and the reduction ratio dependency Characteristic diagram showing the reduction ratio dependency of the ratio of the coercive force HcJ⊥ in the vertical direction and the coercive force HcJ // in the in-plane direction Conceptual diagram of simultaneous control of anisotropy and flexibility by rolling, and control of anisotropy between electrodes

Explanation of symbols

A oligomer B polymer C chemical contact N type of magnetic pole (the direction of the arrow is the magnetization direction of the magnet)
S Type of magnetic pole (the direction of the arrow is the magnetization direction of the magnet)
HcJ⊥ vertical coercive force HcJ // in-plane coercive force Mmax⊥ vertical maximum magnetization Mmax // in-plane maximum magnetization

Claims (6)

When the maximum magnetization in the vertical direction is Mmax⊥ and the maximum magnetization in the in-plane direction is Mmax //, the Mmax⊥ / Mmax // population dispersion before and after rolling, and the perpendicular magnetic anisotropy with no difference in the population mean with a probability of 95% For manufacturing a radial magnetic anisotropic magnet motor that changes the direction of anisotropy of a magnetic thin plate magnet to a radial direction. When the lower limit of Mmax / Mmax // is 1.45, the coercivity in the vertical direction is HcJ⊥, and the coercivity in the in-plane direction is HcJ //, HcJＪ / HcJ // is 0.90 ± 0.00. The method for manufacturing a radial magnetic anisotropic magnet motor according to claim 1, wherein the direction of anisotropy of the perpendicular magnetic anisotropic thin plate magnet which is 01 is changed to the radial direction. 2. A radial according to claim 1, wherein the direction of the magnetic anisotropy of the perpendicular magnetic anisotropic thin plate magnet in which Mmax / Mmax // between the magnetic poles is smaller than Mmax / Mmax // at the center of the magnetic pole is changed to the radial direction. Manufacturing method of magnetic anisotropic magnet motor. 2. The method of manufacturing a radial magnetic anisotropic magnet motor according to claim 1, wherein the thickness of the magnet at the magnetic pole center is 1.35 mm or less. Claim 1 radial anisotropic magnet motor manufacturing method according to the magnet powder is a mixed magnets of Sm ₂ Fe ₁₇ N ₃ fine powder and polycrystalline aggregate-type Nd ₂ Fe ₁₄ B grains. The radial magnetic anisotropic magnet motor according to claim 1, wherein a maximum energy product (BH) _{max of the} magnetic pole portion is 140 kJ / m ³ or more.

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