JP5958685B2 - Powder molded body manufacturing method, rotating machine part manufacturing method, and rotating machine part - Google Patents

Description

  The present invention relates to a rotating machine magnet used for a permanent magnet of a rotating machine such as a motor or a generator, a rotating machine part including the permanent magnet, and a rotating machine. In particular, the present invention relates to a rotating machine magnet, a rotating machine part, and a rotating machine that can contribute to an improvement in torque and an excitation voltage.

  Rare earth magnets are widely used as permanent magnets for motors (for example, specification 0027 of Patent Document 1). Rare earth magnets are R-Fe-B alloys (R: rare earth elements) such as Nd (neodymium) -Fe (iron) -B (boron) and R-Fe such as Sm (samarium) -Fe-N (nitrogen) alloys. Examples thereof include a bonded magnet formed by molding a mixture of -N based alloy powder and a binding resin. Bond magnets have a higher degree of freedom in shape than sintered magnets, and can be easily formed into a desired shape.

On the other hand, Patent Document 2 discloses an alloy containing rare earth elements and Fe (e.g., Sm ₂ Fe ₁₇ ) as a magnet powder from which a rare earth magnet having excellent magnet characteristics and excellent magnet characteristics is obtained. A multiphase powder having a structure in which rare earth element hydride phases (for example, SmH ₂ ) exist discretely in the contained phase has been proposed. By using this magnet powder, a powder compact with a high relative density can be obtained. By subjecting this dense powder compact to dehydrogenation and nitriding as appropriate, the proportion of the magnetic phase is high and the magnet characteristics are high. Rare earth magnets excellent in the above can be obtained.

JP 2008-301666 A JP 2011-137218 A

  Improvement of characteristics is desired in rotating machines such as motors and generators. For example, an improvement in torque is desired for a motor, and an excitation voltage is desired for a generator.

  As a method for improving the characteristics of the rotating machine, an air gap formed between the rotor and the stator, typically an air gap formed by one surface of a permanent magnet and an end surface of a tooth (magnetic pole) on which a coil is arranged. It is conceivable to increase

  Patent Document 1 discloses an axial gap type motor in which an air gap exists in a disc-shaped plane with the rotation axis of the motor as a normal line. In this motor, the rotor body has an umbrella shape, and the surface of the rotor body is inclined with respect to the rotation axis of the motor, and a rotor in which a permanent magnet having a rectangular cross section is fixed to the surface of the inclined rotor body; The stator body has a trapezoidal cross section, and the stator body surface is inclined with respect to the rotation axis of the motor, and the inclined surface is provided with a stator having a rectangular cross section. With the above configuration, one surface forming the air gap in the permanent magnet and the end surface forming the air gap in the teeth are both inclined with respect to the rotation axis of the motor, and as a result, the air gap is also inclined. Is done. Therefore, the motor has the same outer diameter as this motor (= the outer diameter of the rotor body = the outer diameter of the stator body), and one surface of the permanent magnet and the end surface of the teeth arranged opposite to the one surface are the motor. Compared with a configuration (hereinafter referred to as conventional configuration 1) arranged perpendicular to the rotation axis, the air gap provided between both surfaces is large, and the torque can be improved. However, because the rotor body is umbrella-shaped and the permanent magnets are arranged near the outer peripheral edge thereof, the weight balance of the rotor is biased. There is a possibility that the air gap cannot be maintained in a desired size by shaking in the direction. The torque cannot be improved sufficiently because the air gap cannot be maintained at a desired size.

  On the other hand, in a radial gap type motor in which an air gap is provided in a cylindrical outer peripheral surface with the rotation axis of the motor as a bus, the air gap is provided so as to be parallel to the rotation axis of the motor (hereinafter referred to as the conventional embodiment 2). Is called). In this embodiment, taking the inner rotor type as an example, the size of the air gap is uniquely determined by the outer diameter of the rotor and the length (axial length) of the rotor along the direction of the rotation axis of the motor. Accordingly, in order to increase the air gap, at least one of increasing the outer diameter of the rotor and increasing the shaft length may be performed, but in any case, the motor is increased in size. Therefore, in this embodiment, the torque is limited by the size of the motor, and it is difficult to improve the torque.

  Moreover, since the above-mentioned bond magnet has a binding resin, it has a small magnetic phase and is inferior in magnetic characteristics, so that it is difficult to further improve torque and excitation voltage.

  Therefore, one of the objects of the present invention is to provide a rotating machine magnet and a rotating machine part that can contribute to an improvement in torque and an excitation voltage. Another object of the present invention is to provide a rotating machine capable of obtaining high torque and high excitation voltage.

  Since the above-described multiphase powder is excellent in moldability, it can be molded into various shapes. Then, the said objective is achieved by setting it as the magnet (powder magnet) shape | molded in the specific shape using the above-mentioned multiphase powder.

  The magnet of the present invention is used for a rotating machine having an air gap between a rotor and a stator, and is composed of an alloy powder containing a rare earth element and Fe, and the filling rate of the alloy powder is 80. Volume% or more. And the magnet for rotary machines of this invention has the inclined surface by which the surface which forms the said air gap is arrange | positioned non-parallel and non-orthogonal with respect to the rotating shaft of a rotary machine.

  The rotating machine component of the present invention is used in a rotating machine including a permanent magnet, and includes the above-described rotating machine magnet as the permanent magnet. The rotating machine component includes a soft magnetic member made of a soft magnetic material and supporting the rotating machine magnet.

  The rotating machine of the present invention includes the magnet for the rotating machine of the present invention. Or the rotating machine of this invention comprises the said components for rotating machines of this invention.

  The magnet for a rotating machine of the present invention and the component for a rotating machine of the present invention are formed between another component member (typically, a tooth including a coil) constituting the rotating machine when assembled to the rotating machine. At least a part of the air gap is disposed to be inclined with respect to the rotation axis of the rotating machine. This air gap is larger than any of the air gaps of the above-described conventional embodiment 1 and conventional embodiment 2 when the outer diameter of the rotating machine is constant. Therefore, the present rotating machine including the magnet for the rotating machine of the present invention and the rotating machine of the present invention including the parts for the rotating machine of the present invention (hereinafter, referred to as the present rotating machine, etc.) In the case of a motor, the torque can be improved, and in the case of a generator, the excitation voltage can be improved.

  Further, since the magnet for a rotating machine of the present invention itself has an inclined surface, the rotor body and the stator body can be flat (typically in the case of a so-called axial gap type rotating machine) or cylindrical (typically, A simple shape such as a so-called radial gap type rotating machine can be used. Therefore, when the magnet of the present invention is used, it is not necessary to make the rotor main body and the stator main body incline with respect to the rotation axis of the motor or to incline them. Therefore, the rotating machine of the present invention can stably rotate the rotor, and is excellent in characteristics from this point.

  Furthermore, the magnet for a rotating machine of the present invention has a sufficiently high filling rate of the above-mentioned specific alloy powder, and is excellent in magnetic properties as compared to a bonded magnet (for example, a sufficiently high magnetic flux density). A rotating machine or the like can improve torque and excitation voltage.

As one form of the present invention, the alloy powder includes one or more elements selected from RE = Y, La, Pr, Nd, Sm, Dy and Ce, Me = Fe or Fe and Co, Ni, Mn and Ti. One or more elements selected from x, from 1.5 to 3.5, from RE ₂ Me ₁₄ B, RE ₂ Me ₁₄ C, RE ₂ Me ₁₇ N _x , RE ₁ Me ₁₂ N _x and RE ₁ Me ₁₂ The form comprised from the 1 or more types of selected alloy is mentioned.

RE ₂ Me ₁₄ B, RE ₂ Me ₁₄ C, RE ₂ Me ₁₇ N _x , RE ₁ Me ₁₂ N _x , RE ₁ Me ₁₂ (x = 1.5 to 3.5) are all excellent in magnetic properties. The rotating machine magnet and the rotating machine part can contribute to further improvement of the torque and the excitation voltage, and the rotating machine of the above configuration can further improve the torque and the excitation voltage.

  As one form of the parts for a rotating machine of the present invention, a form constituted by a molded body obtained by pressure-molding magnetic powder can be mentioned. In this form, the rotating machine magnet is composed of a compact (compact compact) in which the multiphase powder is pressure-molded, and the soft magnetic member is composed of a compact compact in which soft magnetic metal powder is compacted. The The rotating machine component includes a mixing region in which the soft magnetic metal powder and the alloy powder constituting the soft magnetic member are mixed and exist between the rotating machine magnet and the soft magnetic member. Have.

  The present inventor simultaneously forms the above-mentioned multiphase powder having excellent formability and soft magnetic metal powder such as pure iron powder and iron alloy powder used in the compacted body to perform dehydrogenation treatment, and further appropriately nitriding treatment. The magnet region having the above-mentioned inclined surface, which is composed of a recombined alloy powder (or an alloy powder further subjected to nitriding treatment) produced by performing dehydrogenation treatment on the multiphase powder when subjected to heat treatment such as And the member which has a soft-magnetic area | region comprised from a soft-magnetic metal powder was obtained. The obtained member has no clear boundary between the magnet region (magnet) composed of the above-described alloy powder and the region (soft magnetic member) composed of the soft magnetic metal powder, and the powder constituting each region is Interlaced area: A mixed area was formed, and both areas were joined.

  It can be said that the above-mentioned form having a mixed region was obtained by simultaneously forming the above-mentioned multiphase powder and soft magnetic metal powder and then performing heat treatment. The above-mentioned form obtained by this manufacturing method has fewer steps compared to the case where a permanent magnet and a compacted body made of soft magnetic powder are separately produced and integrated, and produces parts for rotating machines. Excellent in properties. In addition, heat treatment such as dehydrogenation treatment and nitriding treatment applied to the powder compact obtained after molding can be used as heat treatment for strain relief for soft magnetic members. Excellent.

  Furthermore, when independent members (permanent magnet and compacted body) manufactured separately as described above are combined and integrated, a minute gap may be generated between the two depending on the design likelihood. On the other hand, since the said form is obtained through simultaneous shaping | molding and heat processing as mentioned above, the said micro clearance gap cannot arise. In addition, both the above-described multiphase powder and soft magnetic metal powder are deformed in the molding step, and the multiphase particles constituting the multiphase powder and the metal particles constituting the soft magnetic metal powder are caused by unevenness on the particle surface. In addition to being able to mesh, multiphase particles and metal particles can also mesh. Therefore, a so-called necking strength is developed between the multiphase particles, between the metal particles, and between the multiphase particles and the metal particles, and a powder compact having excellent bonding properties between the particles can be obtained. This powder molded body is excellent in strength due to the expression of the necking strength and the absence of the minute gaps, and hardly collapses during production. The above-mentioned form obtained by subjecting the powder molded body having excellent strength to the heat treatment described above is also excellent in strength. In addition, the above-described configuration in which the fine gap is not provided between the magnet for a rotating machine and the soft magnetic member is excellent in magnetic characteristics because there is substantially no energy loss (leakage magnetic field) of the generated magnetic field of the magnet. Furthermore, when both the multiphase powder and the soft magnetic metal powder include an Fe component, it is expected that the adhesiveness is excellent and cracking is unlikely to occur between the rotating machine magnet and the soft magnetic member.

  The rotating machine magnet and rotating machine parts of the present invention can contribute to improvement of torque and excitation voltage. The rotating machine of the present invention can improve torque and excitation voltage.

(A) is a schematic perspective view showing a rotating machine part of Embodiment 1, and (B) is an exploded perspective view thereof. FIG. 5 is an explanatory view for explaining a rotating machine produced in Test Example 1. (A) is an explanatory view for explaining the shape of the magnet of form A produced in Test Example 1, and (B) is an explanatory view for explaining the shape of the magnet of Form B produced in Test Example 1. FIG. 5 is an explanatory view for explaining a molding die used for manufacturing the rotating machine component of the first and second embodiments. (A) is a plan view of a rotating machine component of Embodiment 3, and (B) is a schematic cross-sectional view of the rotating machine member cut along a (B)-(B) plane along the rotation axis. It is explanatory drawing explaining the metal mold | die used for manufacture of the components for rotary machines of Embodiment 3, 4. FIG.

Hereinafter, the present invention will be described in more detail.
[Magnet for rotating machine]
The magnet for a rotating machine of the present invention typically has a magnet powder as described in Patent Document 2, that is, a specific multiphase powder is pressure-molded into a desired shape, and then subjected to dehydrogenation treatment and appropriate nitriding treatment. Examples thereof include an alloy powder made of a recombination alloy produced through the process and an alloy powder made of a nitrided alloy. The specific alloy composition is one or more elements selected from RE = Y, La, Pr, Nd, Sm, Dy and Ce, Me = Fe alone, or selected from Co, Ni, Mn and Ti More than seed element and Fe, when x = 1.5 ~ 3.5, it is selected from RE ₂ Me ₁₄ B, RE ₂ Me ₁₄ C, RE ₂ Me ₁₇ N _x , RE ₁ Me ₁₂ N _x and RE ₁ Me ₁₂ One or more of them. More specifically, RE ₂ Me ₁₄ B is Nd ₂ Fe ₁₄ B, Nd ₂ (Co ₁ Fe ₁₃ ) B, RE ₂ Me ₁₄ C is Nd ₂ Fe ₁₄ C, RE ₂ Me ₁₇ N _x is Sm ₂ Fe ₁₇ N ₃ , Y ₂ Fe ₁₇ N ₃ , RE ₁ Me ₁₂ N _x are Sm ₁ (Ti ₁ Fe ₁₁ ) N ₂ , Sm ₁ (Mn ₁ Fe ₁₁ ) N ₂ , Y ₁ (Ti ₁ Fe ₁₁ ) N ₂ , Y ₁ (Mn ₁ Fe ₁₁ ) N ₂ , RE ₁ Me ₁₂ are Sm ₁ (Ti ₁ Fe ₁₁ ), Sm ₁ (Mn ₁ Fe ₁₁ ), Y ₁ (Ti ₁ Fe ₁₁ ), Y ₁ (Mn ₁ Fe ₁₁ ) and the like. In particular, an alloy in which RE is Nd or Sm, more specifically an Nd—Fe—B alloy or an Sm—Fe—N alloy is preferable because of excellent magnetic properties. Alloys are allowed to contain elements added for various purposes (eg, controlling crystal growth, etc.) during manufacture: Cu, Al, Cr, Si, Ga, Nb, and the like.

  The magnet for a rotating machine of the present invention has a high filling rate of the alloy powder constituting the magnet and is 80% by volume or more. For example, the filling rate tends to increase as the relative density increases in the molding step of the powder compact to be described later. The higher the filling rate, the better the magnetic properties, so the filling rate is more preferably 85% by volume or more.

  The average particle diameter of the alloy particles constituting the magnet for a rotating machine of the present invention is 10 μm to 500 μm, further 30 μm or more, and particularly 100 μm or more and 350 μm. Since the average particle size of the alloy particles in the magnet depends on the average particle size of the multiphase powder used for the raw material, the size of the raw material powder may be adjusted so that the alloy particles have a desired size. Unlike a sintered body, a magnet manufactured using a multiphase powder can confirm the grain boundary (alloy particle contour) of the powder.

  Typical shapes of the magnet for a rotating machine of the present invention include an annular body, a fan-shaped columnar body obtained by dividing the ring into predetermined inner angles, and a prismatic body similar to a fan-shaped body. In the magnet for a rotating machine according to the present invention, a surface that forms an air gap when assembled to the rotating machine (hereinafter referred to as a magnet gap surface) is non-parallel and non-orthogonal with respect to the rotating shaft of the rotating machine. It has an inclined surface to be arranged. This inclined surface takes a plane orthogonal to the rotation axis (= plane having the rotation axis as a normal line), and an angle formed by this plane and the inclined surface (hereinafter referred to as an inclination angle) is more than 0 ° and less than 90 ° It is a surface that satisfies.

  For example, in an axial gap type rotating machine, the larger the tilt angle is, the more the magnet gap surface is compared to the configuration in which the tilt angle is 0 °, that is, the magnet gap surface is arranged so as to be orthogonal to the rotation axis. The air gap can be increased. However, the greater the tilt angle, the larger the magnet length (length along the rotation axis direction), leading to an increase in the size of the rotating machine. When used in a so-called axial gap type rotating machine, the inclination angle of the inclined surface of the magnet for a rotating machine of the present invention is preferably 3 ° to 30 °, particularly preferably 10 ° to 30 °.

  On the other hand, in the radial gap type rotating machine, the smaller the tilt angle, the smaller the magnet gap surface compared to the configuration in which the tilt angle is 90 °, that is, the magnet gap surface is arranged so as to be parallel to the rotation axis. The air gap can be increased. However, the smaller the inclination angle, the larger the maximum width of the magnet (the length along the direction perpendicular to the rotation axis direction), leading to an increase in the size of the rotating machine. When used in a so-called radial gap type rotating machine, the inclination angle of the inclined surface of the magnet for a rotating machine of the present invention is preferably 60 ° to 87 °, particularly preferably 60 ° to 80 °.

  It can be set as the form which provided the some inclined surface from which an inclination angle differs in the magnet gap surface. This configuration makes it easier to further increase the magnet gap surface. On the other hand, the form with one inclined surface provided in the magnet gap surface has a simple magnet shape and is excellent in moldability and productivity. The magnet gap surface is configured only by an inclined surface, and in other magnets used in so-called axial gap type rotating machines, an inclined surface and a surface having an inclination angle of 0 ° (hereinafter referred to as an orthogonal surface) The magnet used for the so-called radial gap type rotating machine can be configured to have an inclined surface and a surface having an inclination angle of 90 ° (hereinafter referred to as a parallel surface). In the form having at least one orthogonal surface or parallel surface, the orthogonal surface or parallel surface can be used as a pressure-receiving surface (surface pressed by the punch) during molding, and the moldability is excellent. When the area ratio of the inclined surface in the magnet gap surface is 60% or more, particularly 70% or more, the area of the magnet gap surface can be sufficiently increased.

  In the form in which the magnet for a rotating machine of the present invention is independent of a soft magnetic member to be described later and is attached to the rotating machine main body, the surface facing the inclined surface is a contact surface with the rotating machine main body. In a magnet used for a so-called axial gap type rotating machine, this contact surface is provided so as to be orthogonal to the rotation axis of the rotating machine (parallel to the above-described orthogonal plane) and used for a so-called radial gap type rotating machine. The magnet is provided so as to be parallel to the rotating shaft of the rotating machine and the parallel plane described above.

[Rotating machine parts]
(Soft magnetic material)
The rotating machine component of the present invention includes the above-described rotating machine magnet and a soft magnetic member. The soft magnetic member mainly functions as a mechanical support member for the magnet for a rotating machine of the present invention and as a magnetic coupling member (yoke member) for constituting a magnetic circuit. Examples of the soft magnetic material constituting the soft magnetic member include a ceramic material such as a ferromagnetic transition metal such as Fe, Co, and Ni, an alloy containing a ferromagnetic transition metal element, and a spinel ferrite made of iron oxide. In particular, pure iron composed of Fe and inevitable impurities, and iron alloys mainly composed of Fe (eg Fe-Si alloys, Fe-Ni alloys, Fe-Al alloys, Fe-Co alloys, Fe-Cr alloys) Iron-based materials such as alloys, Fe-Si-Al alloys, and various steels such as silicon steel can easily obtain a soft magnetic member having a saturation magnetic flux density higher than that of the ferrite. A known soft magnetic material can be used.

  The soft magnetic member is a powder compact obtained by subjecting a powder compact obtained by pressure-molding the powder made of the soft magnetic material to a heat treatment (mainly for the purpose of removing distortion), and a sintered compact obtained by sintering the powder compact. Examples thereof include a combination and a laminate formed by laminating the above-described soft magnetic materials. In the green compact, the strength can be increased by arranging a reinforcing material on the outer periphery thereof (for example, by fitting a belt-like annular body).

  When the magnet for a rotating machine of the present invention and the soft magnetic member are independent members, they can be integrated using a fixing material such as an adhesive, a fastening member such as a bolt / nut or a screw. In addition, when the soft magnetic member is the above-mentioned green compact, the multiphase powder used for manufacturing the magnet and the soft magnetic powder (particularly metal powder) used for manufacturing the green compact are simultaneously used. A molded powder molded body (hereinafter referred to as a composite powder molded body) is produced, and the composite powder molded body is subjected to a heat treatment such as a dehydrogenation treatment without using the above-described fixing material. A rotating machine component in which a magnet and a soft magnetic member are integrated (one form of the rotating machine member of the present invention) is obtained. This rotating machine component is composed of the above-mentioned specific alloy powder, and includes an area having an inclined surface (magnet for rotating machine), an area consisting of soft magnetic metal powder (soft magnetic member), and a gap between both areas. And a mixed region where the alloy powder and the soft magnetic metal powder are mixed, the boundary between the magnet for the rotating machine and the soft magnetic member is unclear, and there is no clear boundary. This rotating machine component has (1) a small number of processes and excellent productivity, (2) high strength due to the above-mentioned necking strength manifestation and the absence of minute gaps, and (3) the aforementioned minute gaps. There is a unique effect of being excellent in magnetic characteristics when it is not present.

  Since the metal particles constituting the soft magnetic member maintain the composition of the soft magnetic metal powder used as a raw material, the metal particles are made of the above-described pure iron, iron alloy, or the like.

  When the soft magnetic member is a green compact, the average particle size of the soft magnetic particles constituting the green compact can be selected as appropriate. Since the composition and average particle diameter of the soft magnetic member depend on the soft magnetic powder used as the raw material, the size of the raw material powder is preferably adjusted so that the soft magnetic particles have a desired composition and size. In particular, when producing the above-mentioned composite powder molded body, the average particle diameter of the metal particles constituting the soft magnetic metal powder is 10 μm to 500 μm, more preferably 30 μm to 300 μm, and particularly 50 μm to 200 μm. Excellent.

  Thickness of the mixing zone (in the case of parts used for so-called axial gap type rotating machines, the length along the rotating axis direction, in the case of parts used for so-called radial gap type rotating machines, the direction orthogonal to the rotating axis direction The length along the length depends on the size of the alloy particles constituting the rotating machine magnet and the size of the soft magnetic metal particles constituting the soft magnetic member. The specific thickness may be equal to or greater than the larger average particle size of the average particle size of the alloy powder and the average particle size of the soft magnetic metal powder. In this case, the particles having a smaller average particle diameter can be sufficiently interposed in the gap formed by the larger particles. A more specific thickness is, for example, 100 μm or more.

[Rotating machine]
Examples of the rotating machine of the present invention include a motor or a generator including the above-described magnet for rotating machine of the present invention and parts for the rotating machine of the present invention. More specifically, a so-called axial gap type rotating machine (either a single type or a double type) or a so-called radial gap type rotating machine may be mentioned. The magnet for a rotating machine of the present invention is used as a permanent magnet in the stator or rotor of the rotating machine, and the component for a rotating machine of the present invention is used as a stator or rotor of the rotating machine.

[Production method]
The magnet for a rotating machine of the present invention can be manufactured, for example, through a process of preparation process: preparation of raw material powder ⇒ molding process: formation of a powder compact ⇒ dehydrogenation process: dehydrogenation heat treatment (⇒ nitriding process: nitriding process). it can. The rotating machine component of the present invention is manufactured, for example, by separately preparing a soft magnetic member made of the above-described soft magnetic material and attaching the rotating machine magnet of the present invention to a predetermined position using the above-described fixing material. Can do. Alternatively, when the component for a rotating machine of the present invention is an integrally molded product of the magnet for the rotating machine of the present invention and a soft magnetic member, the preparation step further includes a soft magnetic metal powder for constituting the soft magnetic member. Prepared in the molding process, producing a composite powder compact that was molded simultaneously with the raw material powder for the magnet and the soft magnetic metal powder. In the dehydrogenation process and nitriding process, the composite powder compact was manufactured by applying the heat treatment described above. can do. Hereinafter, the outline of each process will be described.

(Preparation process)
In the raw material powder of the magnet for a rotating machine of the present invention, a precursor powder that becomes a recombination alloy by dehydrogenation treatment, specifically, a rare earth element hydrogen compound phase and an Fe-containing material phase are discretely present. A multiphase powder composed of multiphase particles having a structure is prepared. When producing a composite powder compact, a soft magnetic metal powder is also prepared.

[Multiphase powder]
Each multi-phase particle constituting the multi-phase powder is a structure in a hydrogen disproportionation decomposition state, typically with the phase of the Fe-containing material as the parent phase (Fe-containing content: 60 vol% or more), The matrix has a structure in which granular rare earth element hydrogen compounds (more than 0 vol%, preferably 10 vol% or more) are dispersed. In the above structure, the spacing between the phases of the rare earth element hydrogen compounds adjacent to each other through the Fe-containing material phase is typically 0.5 μm or more (preferably 1 μm or more) and 3 μm or less. Fe content is (1) Fe (pure iron) only, (2) at least one element selected from Co, Ga, Cu, Al, Si, Cr and Nb (hereinafter referred to as a substitution element) and Fe, (3) A compound containing Fe (for example, FeTi, FeMn, Fe ₃ B, Fe ₂ B, FeB, etc.) and Fe, (4) any one of (1) to (4), which is a substitution element, the above compound and Fe The form is mentioned.

  The multiphase powder is obtained by subjecting the starting alloy powder to a hydrogenation treatment, and the production method described in Patent Document 2 can be suitably used for its production.

The starting alloy is, for example, selected from RE _x Me ₁₄ B, RE _x Me ₁₄ C, RE _x Me ₁₇ and RE _{x / 2} Me ₁₂ using the above-mentioned RE and Me (where x = 2.0 to 2.2). 1 type or more is mentioned. More specifically, RE _x Me ₁₄ B is Nd ₂ Fe ₁₄ B, Nd ₂ (Co ₁ Fe ₁₃ ) B, RE _x Me ₁₄ C is Nd ₂ Fe ₁₄ C, RE _x Me ₁₇ is Sm ₂ Fe ₁₇ , Y ₂ Fe ₁₇ , RE _{x / 2} Me ₁₂ are Sm ₁ (Ti ₁ Fe ₁₁ ), Sm ₁ (Mn ₁ Fe ₁₁ ), Y ₁ (Ti ₁ Fe ₁₁ ), Y ₁ (Mn ₁ Fe ₁₁ ). In particular, an alloy containing Sm or Nd can provide a magnet having excellent magnet characteristics. In addition, the starting alloy is allowed to contain an element (such as the above-mentioned Cu, Al, Si, Ga, Nb, etc.) that controls crystal growth when changing from a multiphase structure to a recombination alloy structure. A plurality of types of multiphase powders having different materials can be used in combination. A starting alloy powder having a desired composition is prepared, and a starting alloy powder is obtained by using a known powder manufacturing method (such as a gas atomizing method or a method including pulverization) as described in Patent Document 2. In particular, the atomization method is easy to produce a powder having a high sphericity and excellent filling properties at the time of molding.

The conditions for the hydrogenation treatment are as follows: atmosphere: single atmosphere of only hydrogen (H ₂ ), or mixed atmosphere of hydrogen (H ₂ ) and inert gas such as Ar and N ₂ , temperature: disproportionation temperature to 1100 ° C Holding time: 0.5 hours or more and 5 hours or less. The specific temperature is 700 ° C. or more and 900 ° C. or less, Nd ₂ Fe ₁₄ B, when the starting alloy is, for example, Sm ₂ Fe ₁₇ , Sm ₁ (Ti ₁ Fe ₁₁ ), Sm ₁ (Mn ₁ Fe ₁₁ ), etc. In the case of Nd ₂ (Co ₁ Fe ₁₃ ) B, Nd ₂ Fe ₁₄ C, and the like, the temperature may be 750 ° C. or higher and 900 ° C. or lower. For the hydrogenation treatment, the disproportionation conditions in the known HDDR treatment can be applied.

  In consideration of moldability and filling rate, the average particle size of the multiphase powder is preferably 10 μm or more and 500 μm or less, more preferably 30 μm or more, and even more preferably 100 μm or more and 350 μm or less. If the alloy particles constituting the magnet have a large particle size, deterioration of magnetic properties due to surface layer oxidation can be suppressed. Therefore, if a multiphase powder having a relatively large particle size is used as a raw material, a magnet having excellent magnetic properties can be obtained. Since the size of the multiphase powder depends on the starting alloy powder, the size of the starting alloy powder and the hydrogenation conditions may be adjusted so that the multiphase powder has a desired size. A plurality of powders having different average particle sizes may be used. By using finely mixed powder, the relative density of the powder compact can be increased, and a dense magnet can be formed.

  In addition, as described in Patent Document 2, if the form is provided with an anti-oxidation layer and an insulating film so as to cover the entire circumference of the multiphase particles, the anti-oxidation of the new surface generated at the time of molding, the increase in the electric resistance of the magnet, etc. Can be planned. The material of the insulating coating can be selected as appropriate. When the electrical resistance may be low (for example, when the application is a motor operating at a low speed, a rotor of a generator, or the like), the insulating coating may not be provided. The same applies to the soft magnetic metal powder described later.

[Soft magnetic metal powder]
As the soft magnetic metal powder, powders made of soft magnetic materials having various compositions conventionally used for compacted products can be used. The above-mentioned iron-based materials, especially pure iron and iron alloys with a small amount of additive elements (for example, Fe-Si alloys, Si content: 2.5 mass% or less, Fe-Al alloys, Fe-Ni alloys, etc.) ) Is excellent in moldability. A plurality of types of soft magnetic metal powders having different materials can be used in combination.

  It can be set as the form which provides an insulating film on the surface of the metal particle which comprises soft-magnetic metal powder. In this case, the soft magnetic member in the obtained rotating machine component has an insulating film (or an insulator generated by a heat treatment such as a dehydrogenation process, a subsequent nitriding process, or an annealing process described later) between the metal particles. As a result, the electrical resistance increases, and for example, eddy current loss can be reduced.

  The average particle size of the soft magnetic metal powder is preferably about 10 μm to 500 μm because it is easy to handle and excellent in moldability. A plurality of powders having different average particle sizes may be used. In particular, when a hard alloy powder is used, by using a finely mixed powder, the relative density of the powder compact can be increased and a dense soft magnetic member can be formed.

  The average particle size may be different between the multiphase powder and the soft magnetic metal powder, or may be equal. If the average particle size of both powders is the same, it depends on the strength and hardness of both powders, but it is easy to adjust the pressing pressure during molding, and it is possible to uniformly apply pressure, and it is a composite powder with excellent dimensional accuracy and appearance It is easy to obtain a molded body.

(Molding process)
A molding die is selected so as to obtain a magnet having a desired shape, the above-mentioned multiphase powder is supplied to the molding die, and pressed and compressed to form a powder molded body (hereinafter referred to as a multiphase powder molded body). Called). When forming a rotating machine part including a soft magnetic member, the multiphase powder and the soft magnetic powder are supplied to a molding die having a desired shape in a laminated state, and simultaneously pressed and compressed. A composite powder compact is formed. The order of feeding the multiphase powder and the soft magnetic metal powder is not particularly limited as long as a composite powder molded body having a desired shape is obtained.

  The higher the relative density (actual density with respect to the true density of the powder compact) of both the multiphase powder compact and the composite powder compact, the magnet or soft magnetic member with a high density of the magnetic phase finally Easy to get. Therefore, it is preferable to adjust the pressure so that the relative density of any powder compact is 85% or more, preferably 90% or more. In the form in which the multiphase powder is provided with the above-mentioned antioxidant layer, if the relative density of the multiphase powder molded body or the relative density of the region made of the multiphase powder in the composite powder molded body is about 90% to 95%, the post-process It is easy to remove the antioxidant layer by heat treatment.

Since the multiphase powder is excellent in moldability like the soft magnetic metal powder used as a raw material of a conventional compacted body, the pressure during molding can be made relatively small. For example, the pressure during molding of the multiphase powder molded body and the composite powder molded body can be 8 ton / cm ² or more and 15 ton / cm ² or less.

  Since multiphase powders containing rare earth elements are particularly easily oxidized, it is preferable to use a non-oxidizing atmosphere in the molding step because it can prevent oxidation of the multiphase powder and soft magnetic metal powder. In the form in which the multiphase powder includes the above-described antioxidant layer, the forming step may be performed in an oxygen-containing atmosphere such as an air atmosphere.

  In addition, in the molding process, by appropriately heating the molding die, it is possible to promote deformation of the multiphase powder, and it is easy to obtain a powder molded body having a complicated shape such as a high-density powder molded body or an inclined surface. . Moreover, it is easy to release the powder compact by applying a lubricant to the molding die as appropriate.

Further, the molding process may be pressurized and compressed in multiple stages. In particular, when molding a composite powder compact using different powders, pressurizing in multiple stages allows the next powder to be filled without disrupting the powder already filled in the molding die, and integrated molding with high accuracy. Is preferable. When multi-stage molding is performed, in the middle stage, the pressure at the time of molding is relatively small, and when the pressure is increased to some extent after the movement of the powder is completed, (1) density due to pressurization divided into multiple stages There are advantages such that stress due to the difference can be relieved, and (2) it is easy to mold and densify. The specific conditions are that the intermediate stage pressure is about ¹ ton / cm ² to ³ ton / cm ^2, and that the intermediate stage molded body (temporary molded body) has a relative density of about 75% or less. Is mentioned. Alternatively, the composite powder molded body can be formed by appropriately placing a shape-retaining material made of a material (for example, paraffin or the like) that can be lost by heat treatment after molding (such as dehydrogenation) in a molding die. Easy to mold.

  In the obtained multiphase powder molded body, the multiphase particles are meshed with each other, and the meshing provides high strength. The composite powder molded body includes a metal powder region made of soft magnetic metal powder and a multiphase powder region made of multiphase powder. In the multiphase powder region, the multiphase particles mesh with each other, and in the metal powder region, the metal particles Engage with each other. In addition, between the two regions, the multiphase particles and the soft magnetic metal particles are mixed and there is no clear boundary. In the region where the different kinds of particles are mixed, the multiphase particles and the metal particles are meshed with each other. Therefore, the obtained composite powder molded body has high strength due to the above-described meshing and is difficult to disintegrate during production. In addition, the thickness of the region where the multiphase particles and the soft magnetic metal particles are mixed varies depending on the particle diameters of the two powders, and depends on the powder having the larger average particle diameter.

(Dehydrogenation process)
In the dehydrogenation step, in the multiphase powder, hydrogen is separated from the multiphase particles, and the rare earth element and the Fe-containing material are combined to form a single-phase structure composed of a recombination alloy from the multiphase structure. It is a process. In the soft magnetic metal powder provided in the composite powder molded body, the dehydrogenation step is a step for removing strain introduced by the molding. For the hydrogen separation, the heat treatment (dehydrogenation treatment) atmosphere in the dehydrogenation step is a non-hydrogen atmosphere such as an inert atmosphere or a reduced pressure atmosphere. Examples of the inert atmosphere include Ar and N ₂ . The reduced-pressure atmosphere refers to a vacuum state in which the pressure is lower than that of a standard air atmosphere, and the degree of vacuum is preferably 100 Pa or less, and the final degree of vacuum is preferably 10 Pa or less, and more preferably 1 Pa or less. In a reduced pressure atmosphere, rare earth element hydrogen compounds are unlikely to remain, and a decrease in magnetic properties due to the remaining hydrogen compounds can be suppressed, and a magnet having excellent magnetic properties can be obtained.

  The temperature of the dehydrogenation treatment is not less than the recombination temperature of the multiphase particles and varies depending on the composition, but typically, it includes 600 ° C. or more when Sm is included, and 700 ° C. or more when Nd is included. The higher the dehydrogenation temperature, the more hydrogen can be removed from the multiphase particles and recombination can proceed, and the introduced strain can be easily removed from the metal particles constituting the soft magnetic metal powder. However, if the temperature of the dehydrogenation treatment is too high, there is a concern about volatilization of rare earth elements and coarsening of crystals of the recombination alloy. The retention time for the dehydrogenation treatment is 10 minutes or more and 600 minutes or less. The conditions for the dehydrogenation process can be the conditions for the DR process in the known HDR process.

  In the dehydrogenation step, the dehydrogenation treatment can be performed in a state where a strong magnetic field of 2 T or more is applied to the powder compact. In this embodiment, since the crystal orientation of the crystal nuclei of the recombination alloy can be oriented in one direction by magnetostriction, the magnet provided in the rotating machine magnet or the rotating machine part can be an oriented structure. With this orientation structure (a structure in which the easy axis of magnetization (typically c-axis) of the crystal is oriented in one direction), a magnet having excellent magnet characteristics can be obtained. Since the orientation is improved as the magnetic field is increased, the applied magnetic field can be 3 T or more, further 3.2 T or more, particularly 4 T or more.

  The application direction of the magnetic field is preferably the magnetic flux direction of the magnetic circuit formed in the rotating machine, since the magnetic characteristics of the obtained magnet can be fully utilized. Further, the application direction of the magnetic field is preferably the same as the molding direction (compression direction) when molding the powder compact.

  When applying a high-temperature superconducting magnet for the application of the magnetic field, (1) a strong magnetic field can be stably formed, (2) the magnetic field can be changed at high speed, and (2-1) heat treatment time is shortened, (2 -2) It has advantages such as suppression of coarsening of crystal grains and (2-3) continuous processing. This point can also be applied to the application of a magnetic field in a nitriding step described later.

As a multiphase powder, the above-mentioned RE _x Me ₁₄ B, RE _x Me ₁₄ C, and RE _{x / 2} Me ₁₂ are used as starting alloys, for example, a phase of RE hydride such as Nd, Fe, Fe ₃ B, etc. When a powder composed of multiphase particles including a phase of Fe-containing material is used, alloys such as RE ₂ Me ₁₄ B, RE ₂ Me ₁₄ C, RE ₁ Me ₁₂ etc. A magnet composed of a powder of (binding alloy) is obtained.

(Nitriding process)
On the other hand, as a multiphase powder, the above-mentioned RE _x Me ₁₇ and RE _{x / 2} Me ₁₂ are used as a starting alloy, for example, a phase of a hydrogen compound of RE such as Sm and a phase of an Fe-containing material such as Fe or FeTi. When a powder composed of multiphase particles is used, an alloy such as RE ₂ Me ₁₇ N _x , RE ₁ Me ₁₂ N _x, etc. A magnet composed of a powder of a nitrided alloy) is obtained.

The conditions described in Patent Document 2 can be used as the nitriding conditions. Specifically, atmosphere: atmosphere containing nitrogen element, temperature: nitriding temperature or more and nitrogen disproportionation temperature or less, holding time: 10 minutes or more and 600 minutes or less. Specific atmospheres include (1) a single atmosphere containing only nitrogen, (2) an ammonia (NH ₃ ) atmosphere, (3) a gas containing a nitrogen element such as nitrogen (N ₂ ) or ammonia, and an inert gas such as Ar. Any one of (1) to (4), such as a mixed gas atmosphere, and (4) a mixed gas atmosphere of a gas containing the nitrogen element and hydrogen (H ₂ ) may be mentioned. Since the atmosphere containing hydrogen gas is a reducing atmosphere, the generated nitride can be prevented from being oxidized or excessively nitrided. The nitriding temperature and the nitrogen disproportionation temperature vary depending on the alloy composition before nitriding.For example, in the case of Sm ₂ Fe ₁₇ , Sm ₁ Fe ₁₁ Ti ₁ , 200 ° C. or more and 550 ° C. or less, and further 200 ° C. to 450 ° C., In particular, 200 ° C to 300 ° C can be mentioned.

In the nitriding step in addition to the dehydrogenating step, the nitriding treatment can be performed with a strong magnetic field applied. In this form, the crystal lattice of the recombination alloy can be easily stretched in one direction, and N atoms are preferentially penetrated between the stretched Fe atoms-Fe atoms, and nitrides having an ideal atomic ratio (for example, Sm ₂ It is easy to obtain Fe ₁₇ N ₃ ). A magnet composed of nitride having an atomic ratio in an ideal state and having an oriented structure as described above is further excellent in magnet characteristics. The larger the magnetic field is, the more the magnetic field to be applied can be controlled. Therefore, the applied magnetic field is preferably 3T or more, more preferably 3.5T or more, particularly 3.7T or more, especially 4T or more. The application direction of the magnetic field in the nitriding step is also preferably the magnetic flux direction of the magnetic circuit described above. That is, it is preferable that the application direction of the magnetic field is the same in the dehydrogenation step and the nitridation step. By doing so, it is easy to maintain the oriented structure.

(Annealing process)
When the composite powder compact is subjected to dehydrogenation treatment, if the material after dehydrogenation treatment is further subjected to heat treatment (annealing treatment), thermal strain and interfacial stress that can occur in the material due to dehydrogenation treatment can be removed, and Degradation of characteristics due to strain and interface stress can be suppressed. The annealing conditions are as follows: atmosphere: inert atmosphere or reduced pressure atmosphere, temperature: 250 ° C. to 500 ° C. (preferably 250 ° C. to 450 ° C.), holding time: 1 minute to 600 minutes (preferably 6 minutes to 60 minutes) ). The matter described in the dehydrogenation process can be applied to the specific atmosphere.

  When performing the above-described nitriding step, the nitriding treatment also has the effect of the annealing treatment, so that it is not necessary to perform the annealing treatment separately and can be omitted.

  When the above-described strong magnetic field is applied in the dehydrogenation process or the nitriding process, dehydration can be performed by applying the above-described strong magnetic field (2T or more, preferably 3T or more) in the same direction as in the dehydrogenation process even in the annealing process. It is easy to maintain an aligned structure that is aligned in the elementary process.

  Hereinafter, more specific embodiments of the present invention will be described with reference to the drawings. In the figure, the same reference numerals indicate the same names.

[Embodiment 1]
An example of the rotating machine part of the present invention is a rotating machine part 1A shown in FIG. 1 (A). The rotating machine component 1A includes a rotating machine magnet 1 made of an alloy powder containing a rare earth element and Fe, and a soft magnetic member 2 made of a soft magnetic metal powder. This rotating machine part 1A can be used as a part of a so-called axial gap type rotating machine.

  Here, in the rotating machine component 1A, the rotating machine magnet 1 and the soft magnetic member 2 are independent members, and are integrated by an adhesive or the like.

  This rotating machine magnet 1 is a cylindrical body having a through hole in the center, and connects the inner peripheral surface 12, the outer peripheral surface 13, and both surfaces 12 and 13, and is attached to the soft magnetic member 2. With a contact surface 15 of. The inner peripheral surface 12 and the outer peripheral surface 13 of the magnet 1 are arranged in parallel to the rotating shaft of the rotating machine (indicated by a one-dot chain line in FIGS. 1 and 3) when the magnet 1 is assembled to the rotating machine. 15 is arranged orthogonal to the rotation axis. One of the features of the magnet 1 is that it includes an inclined surface 11 that is disposed non-parallel and non-orthogonally with respect to the rotation axis on the side facing the contact surface 15 (upper side in FIG. 1).

  The inclined surface 11 is another magnetic member (typically a coil as shown in FIGS. 2 and 3) that receives the magnetic flux generated by the magnet 1 in the rotating machine when the rotating machine magnet 1 is assembled to the rotating machine. It functions as a surface that forms an air gap together with the magnetic core 51) of the component 50. When a plane orthogonal to the rotation axis (horizontal plane in FIG. 3) is taken, an angle formed by this plane and the inclined surface 11: the inclination angle θ can be appropriately selected within a range of more than 0 ° and less than 90 ° (here Then, θ = 15 °). In particular, when the inclination angle θ is 10 ° or more and 30 ° or less, the magnet 1 is excellent in moldability, and the magnet 1 has a short length in the rotation axis direction, and can be a small magnet.

  Further, in the rotating machine magnet 1, the magnet gap surface forming the air gap is provided in parallel to the inclined surface 11 and the contact surface 15 (that is, orthogonal to the rotation axis), and is orthogonal to the inner peripheral surface 12 connected to the inner peripheral surface 12. The surface 14i and the outer orthogonal surface 14o connected to the outer peripheral surface 13 are configured. The smaller the total area ratio of the inner orthogonal surface 14i and the outer orthogonal surface 14o in the magnet gap surface, that is, the larger the area ratio of the inclined surface 11, the greater the air gap formation area, so the area ratio of the inclined surface 11 is 60% or more is preferable (70% here).

  This annular magnet 1 for a rotating machine, for example, prepares a multiphase powder as a raw material as described above, and forms a cylindrical powder molded body having an inclined surface using a molding die of a predetermined shape. The powder molded body can be manufactured by subjecting it to dehydrogenation treatment as appropriate and nitriding treatment as appropriate. For example, as shown in FIG. 4 (A), the molding die 300 includes a die 301 provided with a through-hole (here circular hole) 301h, and a cylindrical (here cylindrical) upper punch disposed oppositely. Examples include 302 and a lower punch 303, and a rod-like (cylindrical in this case) thick rod 304 that is inserted through the die 301 and forms a through-hole (inner peripheral surface 12). In the lower punch 303, the surface (pressing surface) facing the upper punch 302 is inclined with respect to the axial direction of the through hole 301h so that the inclined surface 11, the inner orthogonal surface 14i, and the outer orthogonal surface 14o can be formed. It is preferable to use a surface having a surface and a surface (hereinafter referred to as an orthogonal pressing surface) arranged in a direction orthogonal to the axial direction of the through hole 301h. The orthogonal pressing surface can sufficiently apply a pressing force to the multiphase powder P1 between the upper punch 302 and the powder compact can be molded with high dimensional accuracy.

  On the other hand, the soft magnetic member 2 is a circular plate having a through hole: a shaft hole 22 through which a shaft rod 10 (FIG. 2) serving as a shaft of the rotating machine is inserted, and one surface of which is a magnet 1 for the rotating machine. A mounting surface 21 to be attached.

  Here, the soft magnetic member 2 is a compacted body made of soft magnetic powder such as pure iron powder. A known method can be used for manufacturing the green compact.

[Embodiment 2]
Alternatively, as another form of the rotating machine part 1A shown in FIG. 1 (A), a form in which the rotating machine magnet 1 (powder magnet) and the soft magnetic member 2 (powder compact) are integrally molded can be cited. It is done. In the rotating machine component 1A of this embodiment, the above-described alloy powder constituting the rotating machine magnet 1 and the soft magnetic metal powder constituting the soft magnetic member 2 are mixed between the magnet 1 and the soft magnetic member 2. It has a mixed area that exists. The rotating machine component 1A according to the second embodiment is the same as the first embodiment except for the configuration including the above-described mixing region (for example, the shape of the inclined surface 11), and thus the description thereof is omitted.

  The rotating machine component 1A of the second embodiment uses, for example, a molding die 300 shown in FIG. 4 (C), the multiphase powder P1 that is a raw material of the rotating machine magnet 1, and the soft magnetic member 2. It can be produced by forming a composite powder molded body using the soft magnetic metal powder P2 as a raw material, and subjecting this composite powder molded body to dehydrogenation treatment and appropriate nitriding treatment as described above. The molding die 300 further includes a thin rod-shaped (here, cylindrical) thin rod 308 that is inserted into the center of the thick rod 304 to form the shaft hole 22 (FIG. 1). In order to form a composite powder molded body using this molding die 300, first, the lower punch 303 or the like is moved as appropriate, and the inner peripheral surface of the through hole 301h of the die 301 as shown in FIG. The bottomed cylindrical space formed by the pressing surface of the lower punch 303 and the outer peripheral surface of the thick rod 304 is filled with the multiphase powder P1. Next, the lower punch 303, the thick rod 304, etc. are moved as appropriate, and the inner peripheral surface of the through hole 301h of the die 301, the one surface of the multiphase powder P1 and the thick rod 304, and the fine as shown in FIG. The bottomed cylindrical space formed by the outer peripheral surface of the rod 306 is filled with the soft magnetic metal powder P2. Before forming the space filled with the magnetic metal powder P2, the multiphase powder P1 may be lightly pressed by the cylindrical upper punch 302 shown in FIG. Then, as shown in FIG. 4 (C), the multi-phase powder P1 and the magnetic metal powder P2 laminated in a multilayer are integrally formed by the upper punch 302 having the through hole of the thin rod 308, the lower punch 303 and the thick rod 304. A composite powder compact is obtained by pressurizing and compressing. When pressed in multiple stages as described above, a composite powder molded body can be molded with high accuracy.

[Embodiment 3]
Another rotating machine component of the present invention is, for example, a rotating machine component 1R shown in FIG. The rotating machine component 1R includes a rotating machine magnet 1 made of an alloy powder containing a rare earth element and Fe, and a soft magnetic member 2 made of a soft magnetic metal powder. This rotating machine part 1R can be used as a part of a so-called radial gap type rotating machine.

  Here, in the rotating machine component 1R, the rotating machine magnet 1 and the soft magnetic member 2 are independent members, and are integrated by an adhesive or the like.

  This rotating machine magnet 1 is configured by combining a pair of cylindrical bodies 1Ru, 1Rd. Each cylindrical body 1Ru, 1Rd is a deformed cylindrical body having a frustoconical appearance having a through-hole through which a cylindrical soft magnetic member 2 having a shaft hole 22 is inserted and arranged at the center. An inner peripheral surface 12 serving as a contact surface that contacts the outer peripheral surface of the member 2 and an outer peripheral surface that is non-parallel to the inner peripheral surface 12 are provided. This outer peripheral surface becomes an inclined surface 11 arranged non-parallel and non-orthogonal to the rotation axis of the rotating machine (the central axis of the shaft rod 10) when the magnet 1 is assembled to the rotating machine, and serves as a magnet gap surface. Function. Here, the magnet gap surface is substantially composed only of the inclined surface 11 (area ratio of the inclined surface 11 in the magnet gap surface: 100%). By combining a pair of cylindrical bodies 1Ru, 1Rd, the magnet 1 becomes a drum-like body with a wide central portion in the direction of the rotation axis and a narrower width toward the end face as shown in FIG. ing.

  In this embodiment, the inclination angle θ is an angle formed by this plane and the inclined surface 11 when taking a plane orthogonal to the rotation axis of the rotating machine (horizontal plane in FIG. 5 (B)), and the magnitude thereof is 0 It can be appropriately selected within the range of more than 90 ° and less than 90 ° (here, θ = 75 °). In particular, when the inclination angle θ is 60 ° or more and 80 ° or less, the mold 1 is excellent in moldability and the magnet 1 has a short maximum width in the direction perpendicular to the rotation axis, and can be a small magnet. In FIG. 5B, the magnet 1 is shown exaggerated so that the inclination angle θ can be easily understood.

  The frustoconical cylindrical bodies 1Ru, 1Rd are prepared by, for example, preparing a multiphase powder as a raw material as described above, and using a molding die having a predetermined shape, a cylindrical powder molded body having an inclined surface. And can be produced by subjecting this powder compact to a dehydrogenation treatment and a suitable nitriding treatment as described above. For example, as shown in FIG.6 (D), the molding die 400 is opposed to a die 401 provided with a through hole (here, a trapezoidal hole having an inclined surface corresponding to the inclination angle θ) 401h. A cylindrical (here cylindrical) upper punch 402 and lower punch 403, and a rod-like (here cylindrical) thicker that is inserted through the die 401 and forms a through hole (inner peripheral surface 12). A rod (in this embodiment, including two thick rods 404 and 405 shown in FIG. 6D) may be used. The pressing surface of the upper punch and the pressing surface of the lower punch may be appropriately selected according to the annular end surface shape of the cylindrical bodies 1Ru and 1Rd.

  On the other hand, the soft magnetic member 2 is a cylindrical body having a through-hole: shaft hole 22 through which the shaft 10 serving as the shaft of the rotating machine is inserted, and the outer peripheral surface thereof constitutes the rotating machine magnet 1 This is a mounting surface 21 to which the cylindrical bodies 1Ru and 1Rd to be mounted are attached. The soft magnetic member 2 is a compact formed body made of soft magnetic powder such as pure iron powder as in the first embodiment.

  In addition, in the magnetic core 61, which is another component of the rotating machine, the surface that is disposed opposite to the magnetic gap surface (the inclined surface 11 in this case) of the rotating machine magnet 1 and forms an air gap together with the magnet 1 is shown in FIG. As shown in 5 (B), the inclined shape is similar to the magnet gap surface.

[Embodiment 4]
Alternatively, another form of the rotating machine component 1R shown in FIG. 5 is a form in which the rotating machine magnet 1 (a dust magnet) and the soft magnetic member 2 (a dust compact) are integrally molded. In the rotating machine component 1R of this embodiment, the above-described alloy powder constituting the rotating machine magnet 1 and the soft magnetic metal powder constituting the soft magnetic member 2 are mixed between the magnet 1 and the soft magnetic member 2. It has a mixed area that exists. The rotating machine component 1R of the fourth embodiment is the same as that of the third embodiment except for the configuration including the above-described mixing region (for example, the shape of the inclined surface 11), and thus the description thereof is omitted.

  The rotating machine component 1R according to the fourth embodiment includes a truncated cone-shaped cylindrical body 1Ru (or cylindrical body 1Rd) and a cylindrical soft magnetic member 2 having the same length as the cylindrical body 1Ru (1Rd). Are integrated, and two differently shaped solid bodies having a shaft hole 22 at the center are combined. This irregularly shaped solid is obtained by using, for example, a molding die 400 shown in FIG. 6 (A), a multiphase powder P1 that is a raw material of a rotating machine magnet 1, and a soft material that is a raw material of a soft magnetic member 2. It can be produced by forming a composite powder compact using magnetic metal powder P2 and subjecting this composite powder compact to dehydrogenation treatment and appropriate nitriding treatment as described above. In the molding die 400, the lower punch 403 is constituted by a plurality of divided pieces (lower punch pieces 403a and 403b), and is inserted through the centers of the thick rods 404 and 405 to form the shaft hole 22 (FIG. 5). A thin rod-shaped rod 408 (here, a cylindrical shape) is further provided. In order to form a composite powder molded body using the molding die 400, first, the lower punch 403 or the like is appropriately moved and inserted into the through hole 401h of the die 401 as shown in FIG. 6 (A). The bottomed cylindrical space formed by the inner peripheral surface of the lower punch piece 403a, the end surface of the thick rod 404, and the outer peripheral surface of the thin rod 408 is filled with the soft magnetic metal powder P2. Next, as shown in FIG. 6 (B), the soft magnetic metal powder P2 is lightly pressed at the end surfaces of the thick rods 404 and 405 arranged to face each other, and temporary molding is performed. Next, the lower punch piece 403a and the like are appropriately moved, and as shown in FIG. 6C, the inner peripheral surface of the through hole 401h of the die 401, the outer peripheral surface of the soft magnetic metal powder P2 and the thick rod 404, and the lower punch A bottomed cylindrical space formed by the pressing surface of 403 (lower punch pieces 403a and 403b) is filled with the multiphase powder P1. Then, as shown in FIG. 6 (D), the soft magnetic metal powder P2 and the multiphase powder P1 arranged concentrically by the upper punch 402 and the thick rod 405 and the lower punch 403 and the thick rod 404 are integrally pressed and A composite powder molded body is obtained by compression. When pressed in multiple stages as described above, a composite powder molded body can be molded with high accuracy.

  Next, the characteristics of the rotating machine of the present invention including the magnet for rotating machine of the present invention will be described with reference to test examples.

[Test Example 1]
A rotating machine part 1A according to Embodiments 1 and 2 was manufactured, and the rotating machine part 1A was used as a rotor of a rotating machine (here, a generator), and characteristics of the rotating machine including the rotating machine part 1A were examined. .

  Here, the axial part 10 is the axis of the rotating machine, the soft magnetic member 2 is the rotor body, the rotating machine magnet 1 having the inclined surface 11 is the field, and the coil component 50 imitating the stator (FIG. 2) A rotating machine comprising

The rotating machine magnet 1 was manufactured as follows. As a raw material, a powder having an average particle size of 100 μm, and a multiphase powder made of an alloy having a structure in which granular NdH ₂ is discretely present in an Fe-containing material made of Fe, Fe ₃ B, Fe ₂ B, etc. Prepared. This multiphase powder was subjected to heat treatment (powder annealing: 1050 ° C. × 120 minutes, in high concentration argon) to gas atomized powder having an average particle diameter of 100 μm made of a rare earth-iron-boron alloy (Nd ₂ Fe ₁₄ B), The mixture was once cooled and then subjected to hydrogenation treatment at 800 ° C. for 1 hour in a hydrogen (H ₂ ) atmosphere. A cylindrical powder compact having an inclined surface was formed from the multiphase powder using a molding die as described above (see FIG. 4) (pressure at molding 10 ton / cm ² ). In addition, in the sample in which the magnet 1 and the soft magnetic member 2 are integrally molded, a bottomed cylindrical composite powder molded body was formed using the above-described multiphase powder and pure iron powder described later (at the time of integral molding). Pressure 10ton / cm ² ). When the relative density of the region formed with the multiphase powder in the obtained powder compact and composite powder compact was examined, it was 90%. For the measurement of the relative density, as described in Patent Document 2, the actual density was measured with a commercially available density measuring device, and the true density was obtained by calculation.

The obtained powder compact and composite powder compact were heated to 750 ° C. in a hydrogen atmosphere, then switched to vacuum (VAC), in vacuum (VAC) (final vacuum: 1.0 Pa), 750 ° C. × Dehydrogenation treatment was performed for 60 minutes. Through this process, a cylindrical magnet 1 having an inclined surface 11 (FIG. 1), or a cylindrical magnet 1 having an inclined surface 11 (FIG. 1) and a disk-shaped soft magnetic member 2 are used. 1A was obtained. In the obtained magnet 1, Nd ₂ Fe ₁₄ B was the main phase (85% by volume or more), and it was confirmed that hydrogen was removed by the dehydrogenation treatment.

For the soft magnetic member 2, pure iron powder (ABC100.30 manufactured by Höganäs AB) having an average particle diameter of 50 μm was used as a raw material. In the sample with the soft magnetic member 2 as a separate body, the raw material powder is pressed and compressed using a separately prepared molding die (pressure during molding: 10 ton / cm ² ), and a disk-shaped powder compact is obtained. It was manufactured by heat treatment (350 ° C. × 2 hours, Ar atmosphere). In addition, as for the average particle diameter, the particle diameter (50% particle diameter) at which the integrated weight is 50% was measured with a laser diffraction particle size distribution apparatus.

  When the filling rate Vf of the alloy powder in the magnet 1 provided in the obtained magnet 1 and the rotating machine component 1A was examined, it was confirmed that it was 87% by volume and 80% by volume or more. The filling rate Vf is obtained as follows. In magnet 1, five or more planes in three directions normal to any three orthogonal axes (x, y, z) are cut out in five or more locations in each direction. Observe and measure with a microscope. The plane filling rate at each cut surface in the x-axis direction is Vx1 to Vx5, respectively, the plane filling rate at each cut surface in the y-axis direction is Vy1 to Vy5, respectively, and the plane filling rate at each cut surface in the z-axis direction is Vz1, respectively. ~ Vz5 ... When the average values of the plane filling rates in the respective axial directions are Vx_ave, Vy_ave, and Vz_ave, the filling rate Vf is Vf = √ (Vx_ave × Vy_ave × Vz_ave). Further, the filling rate of the soft magnetic metal powder (here, pure iron powder) in the soft magnetic member 2 was measured in the same manner. The results are shown in Table 1.

  As shown in FIG. 2, the coil component 50 includes a columnar (here, rectangular parallelepiped) magnetic core 51 made of a soft magnetic material (melted electromagnetic soft iron (SUY-0)), and a winding (enamel) on the outer periphery of the magnetic core 51. And a coil 52 formed by spirally winding a copper wire having a coating. The surface forming the air gap in the magnetic core 51 (the surface facing the inclined surface 11 of the magnet 1 for a rotating machine) and the inclined surface 51s having the same angle as the inclined surface 11 of the magnet 1 are orthogonal to the inner side of the magnet. Like the surface 14i and the outer orthogonal surface 14o, the inner orthogonal surface 51i and the outer orthogonal surface 51o are arranged so as to be orthogonal to the rotation axis of the rotating machine (the central axis of the shaft 10).

  The specifications of the rotating machine member 1A including the rotating machine magnet 1 and the soft magnetic member 2 and the specifications of the coil component 50 are as follows (see FIGS. 2 and 3). The rotating machines having the rotating machine member 1A including the magnet 1 including the inclined surface 11 as constituent members are referred to as sample Nos. 1-1 and 1-2. Sample No. 1-1 is a sample in which the soft magnetic member 2 is a separate member, and Sample No. 1-2 is a sample in which the magnet 1 and the soft magnetic member 2 are integrally formed. The length along the rotation axis direction of the rotating machine (vertical direction in FIGS. 2 and 3) is `` length '', and the length in the direction orthogonal to the rotation axis direction of the rotating machine (horizontal direction in FIGS. 2 and 3). This is called “width”.

(Magnet for rotating machine)
Maximum length l _max1 = 15mm Tilt angle θ = 15 °
Width W ₁ = 10 mm, horizontal length W _{11 of} inclined surface 11 = 7 mm, inner orthogonal surface 14 i width W _14i = outer orthogonal surface ₁₄ o width W _14o = 1.5 mm
Inner diameter r ₁₂ (diameter of inner peripheral surface 12) = 40 mm, outer diameter r ₁₃ (diameter of outer peripheral surface 13) = 60 mm
(Soft magnetic material)
Soft magnetic member outer diameter r ₂ = 60mm
Diameter of shaft rod 10 (shaft hole 22) r ₁₀ = 5 mm
(Coil parts)
Maximum length of magnetic core 51 l ₅₁ = 25mm
Width W ₅₁ = 10 mm of the magnetic core 51, the horizontal length = 7 mm of the inclined surface 51 s, the width of the inner orthogonal plane 51i = outer orthogonal surfaces 51o width = 1.5 mm
Number of turns of coil 52: N = 25
Air gap between rotating machine magnet 1 and coil component 50: g = 1 mm

As a comparison, a bond magnet having the same shape and size as the rotating machine magnet 1, that is, a bond magnet having an inclined surface was prepared. This bond magnet was prepared using a commercially available Nd ₂ Fe ₁₄ B powder (average particle size 50 μm) and a binder resin (polyethylene resin powder), and using a mixture of this powder and resin. A bonded magnet having an inclined surface is attached to the same soft magnetic member 2 as in sample No. 1-1 to produce a rotating machine part, and this rotating machine part and the same coil part 50 as in sample No. 1-1 Rotating machine with sample No.1-100. A magnet having an inclined surface such as the magnet 1 provided in the sample No. 1-1 and the bonded magnet provided in the sample No. 1-100 is referred to as form A.

  As another comparison, in the magnetic core of the magnet and the coil component, the surface that forms the air gap is arranged in a direction orthogonal to the rotation axis of the rotating machine, that is, the surface that forms the air gap is a flat surface. Prepared what will be. Specifically, as shown in FIG. 3 (B), a rectangular parallelepiped magnet 100 whose end face is a rectangular surface and a rectangular parallelepiped magnetic core 510 whose end face is also a rectangular surface were prepared. One rectangular end surface 101 of the magnet 100 and one rectangular end surface 511 of the magnetic core 510 are arranged to face each other, and a space between the both end surfaces 101 and 511 becomes an air gap. A magnet in which the surface that forms the air gap, such as the magnet 100, is configured by a plane orthogonal to the rotation axis is referred to as form B.

Width W ₅₁₀ of the width W ₁₀₀ and magnetic core 510 of the magnet 100 of Form B, the same city as the width W ₅₁ of the width W ₁ and the magnetic core 51 of the magnet in the form A (10 mm), the length of the magnet 100 form B l ₁₀₀ is the average value of the maximum length l _max1 of the magnet 1 and the shortest length, the length l ₅₁₀ of the magnetic core 510 of form B is the average value of the maximum length l ₅₁ of the magnetic core ₅₁ and the shortest length did. The magnetic core 510 is the same as the magnetic core 51 except for the points other than the shape.

This form B magnet was prepared using the same multiphase powder as the raw material used for the magnet 1 of the sample No. 1-1 described above, under the same molding conditions and dehydrogenation conditions as the sample No. 1-1. A magnet (a dust magnet mainly made of Nd ₂ Fe ₁₄ B) and a bonded magnet manufactured using the same raw material as that used for the bonded magnet of Sample No. 1-100 described above were prepared. The powder magnet of this form B is attached to the same soft magnetic member 2 as in sample No. 1-1 with an adhesive to produce a rotating machine part, and this rotating machine part and the magnetic core 510 are provided with a coil 52 (the number of turns). = No. 1-111 is a rotating machine provided with a coil component in which 25) is arranged. A bonded magnet of form B is attached to the same soft magnetic member 2 as sample No. 1-1 with an adhesive to produce a rotating machine component, and this rotating machine component and a magnetic core 510 are provided with a coil 52 (the number of turns = 25). Sample No. 1-112 is a rotating machine provided with a coil component in which is provided). The same multi-phase powder as the raw material used for the magnet 1 of the sample No. 1-1 described above and the pure iron powder described above are integrally formed, and the powder magnet of form B and the soft magnetic member 2 are integrally provided. A rotating machine including a rotating machine component and a coil component in which a coil 52 (the number of turns = 25) is arranged on a magnetic core 510 is referred to as Sample No. 1-113.

  The prepared rotating machine parts of each sample were rotated at 60 rpm by a driving device (not shown), and the maximum excitation voltage of the coil 52 included in the coil parts at this time was measured. The results are shown in Table 1. For sample Nos. 1-100, 1-111, 1-112, and 1-113, in the same way as sample Nos. 1-1 and 1-2, the filling rate of the magnet component in the magnet included in each sample The filling rate of the soft magnetic powder in the soft magnetic member was measured. The results are also shown in Table 1.

  As shown in Table 1, when rotating machines with the same outer diameter are compared with each other, the rotating machine has a rotating machine component comprising a form A magnet having an inclined surface on the surface forming the air gap. It can be seen that the excitation voltage is higher in the machine than in the case where the surface forming the air gap is provided with a magnet of form B configured by a surface orthogonal to the rotation axis. In particular, it can be seen that Sample Nos. 1-1 and 1-2 including a dust magnet made of a specific alloy powder have a higher excitation voltage than Sample No. 1-100 including a bond magnet. The reason for this is considered that the magnets provided in sample Nos. 1-1 and 1-2 have a higher magnetic phase ratio and superior magnet characteristics than the bonded magnets provided in sample No. 1-100.

  In addition, comparing Samples Nos. 1-1 and 1-2, the rotating machine of Sample No. 1-2, which includes a rotating machine part in which a magnet and a soft magnetic member are integrally formed, has a magnet and a soft magnetic member. It can be seen that the excitation voltage is higher than the rotating machine of sample No. 1-1, which is a separate member. Further, when sample No. 1-2 was observed, it had a region where the alloy powder constituting the magnet and the soft magnetic metal powder constituting the soft magnetic member were mixed between the magnet and the soft magnetic member. It was. From this, it is considered that Sample No. 1-2 has a high excitation voltage because there is substantially no gap between the magnet and the soft magnetic member, and substantially no leakage magnetic flux is generated in the gap. It is done.

  The present invention is not limited to the above-described embodiment, and can be modified as appropriate without departing from the gist of the present invention. For example, the specifications of the magnet for a rotating machine (length, width, height, angle of inclination of the inclined surface, area, shape, composition of the inclined surface), manufacturing conditions (temperature during heat treatment, atmosphere, application of magnetic field, etc.), soft The specifications (shape, composition, etc.) of the magnetic member can be changed as appropriate.

  The rotating machine of the present invention can construct various motors such as a high-speed motor provided in, for example, a hybrid vehicle (HEV) and a hard disk drive (HDD), and other generators. The magnet for a rotating machine of the present invention and the parts for a rotating machine of the present invention are used for various motors such as a high-speed motor provided in a hybrid vehicle (HEV), a hard disk drive (HDD), and the like (particularly a rotor). It can be suitably used.

1 Magnet for rotating machine 1A, 1R Parts for rotating machine 1Ru, 1Rd Cylindrical body
10 Shaft bar 11 Inclined surface 12 Inner peripheral surface 13 Outer peripheral surface 14i Inner orthogonal surface
14o Outer orthogonal surface 15 Contact surface
2 Soft magnetic member 21 Mounting surface 22 Shaft hole
50 Coil parts 51,510,61 Magnetic core 52 Coils
51s Inclined surface 51i Inner orthogonal surface 51o Outer orthogonal surface
100 Magnet 101,511 End face
300,400 Mold 301,401 Die 301h, 401h Through hole
302,402 Upper punch 303,403 Lower punch 403a, 403b Lower punch piece
304,404,405 Thick rod 308,408 Thin rod
P1 Multiphase powder P2 Soft magnetic metal powder

Claims (8)

Rotating with an air gap between the rotor and the stator by pressing the magnetic powder using a molding die comprising a die provided with a through hole and an upper punch and a lower punch arranged opposite to each other. and rotating turning point for a magnet used in the machine, it is composed of a soft magnetic material, the production of the powder compact for producing a powder compact for use in rotary machine parts Ru comprising a soft magnetic member for supporting the magnet the rotating machine A method,
The pressing surface of the lower punch or the inner peripheral surface of the die has a mold side inclined surface inclined with respect to the axial direction of the through hole, and the mold side inclined surface and the axial direction of the through hole are in the axial direction. The angle formed by the orthogonal plane is 3 ° or more and 30 ° or less, or 60 ° or more and 87 ° or less,
A multi-phase powder comprising a rare earth element hydrogen compound phase and an Fe-containing material phase is prepared as a raw material for the rotating machine magnet, and a soft magnetic metal powder is prepared as a raw material for the soft magnetic member. A preparatory step of filling the molding die in a laminated state;
A step of simultaneously compressing and compressing the multiphase powder and the soft magnetic metal powder filled in the molding die to produce the powder compact,
In the molding step,
A method for producing a powder compact, wherein the powder compact is compressed and compressed so that the relative density of the powder compact is 85% or more, and the multiphase powder is molded by the mold-side inclined surface.   2. The powder molded body according to claim 1, wherein the pressing surface of the lower punch further includes an orthogonal pressing surface arranged in a direction orthogonal to the axial direction of the through-hole and connected to the mold-side inclined surface. Production method.   The manufacturing method of the powder compact | molding | casting of Claim 1 or Claim 2 compressed and compressed in the state which heated the said metal mold | die.   The rare earth element is Nd or Sm;
  The soft magnetic metal powder is at least one selected from pure iron, Fe-Co alloy, Fe-Si alloy, Fe-Al alloy, and Fe-Ni alloy. The manufacturing method of the powder molded object of any one of these.   The manufacturing method of the components for rotary machines which provide the process of performing a dehydrogenation process to the powder compact manufactured by the manufacturing method of the powder compact of any one of Claims 1-4.   A step of performing a dehydrogenation treatment on the powder molded body produced by the method for producing a powder molded body according to any one of claims 1 to 4,
  A method of manufacturing a rotating machine part comprising a step of performing nitriding treatment or annealing treatment on the material subjected to the dehydrogenation treatment. A magnet for a rotating machine used in a rotating machine having an air gap between the rotor and the stator ;
A soft magnetic member made of a soft magnetic material and supporting the magnet for the rotating machine;
The rotating machine magnet is:
It is composed of an alloy powder containing a rare earth element and Fe, and the filling rate of the alloy powder is 80% by volume or more,
Surface forming the air gap, with respect to the rotational axis of the rotating machine, an inclined surface disposed in a non-parallel and non-orthogonal, continuous with the inclined surface is arranged in a direction perpendicular to the rotational axis and the orthogonal plane ingredients example,
An inclination angle formed by the inclined surface and a plane orthogonal to the rotation axis is 3 ° or more and 30 ° or less,
A rotating machine component comprising a mixed region in which the soft magnetic metal powder and the alloy powder constituting the soft magnetic member are mixed and present between the rotating machine magnet and the soft magnetic member . Used in a rotating machine having an air gap between a rotor and a stator, and a magnet for a rotating machine configured by superposing a pair of truncated cone-shaped cylindrical bodies ;
Composed of a soft magnetic material, integrated inside each deformed cylindrical body, and comprising a cylindrical soft magnetic member that supports each deformed tubular body,
The pair of deformed cylindrical bodies are combined such that the width of the central portion in the rotation axis direction of the rotating machine is wide and the width is narrowed toward the end face,
Each of the modified cylindrical bodies is
It is composed of an alloy powder containing a rare earth element and Fe, and the filling rate of the alloy powder is 80% by volume or more,
Surface forming the air gap, with respect to the rotational axis of the rotating machine, it is arranged in non-parallel and non-orthogonal, the angle of inclination with respect to a plane perpendicular to the rotation axis Ru 87 ° der 60 ° or more inclined surfaces ingredients example,
A rotating machine component comprising a mixed region in which the soft magnetic metal powder and the alloy powder constituting the soft magnetic member are mixed and present between the deformed cylindrical body and the cylindrical soft magnetic member .

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