Toyota Jidosha Kabushiki Kaisha

Fine Sinter Co., Ltd

Jfe Steel Corporation

Eisuke Hoshina

Toshiya Yamaguchi

Osamu Yamashita

Yusuke Oishi

Noritaka Miyamoto

Yasuhiro Endo

Kazutaka Tatematsu

Akira Kano

Dai Kobuchi

Kazuhiro Kawashima

Takashi Kawano

Ryoji Mizutani

Tetsuya Shoji

Naomichi Nakamura

Daisuke Ichigozaki

Tatsuhiko Hiratani

Takeshi Hattori

Daisuke Okamoto

Yutaka Komatsu

Hidefumi Kishimoto

Masaaki Tani

Kenji Harada

Shin Tajima

Noriko Makiishi

Junghwan Hwang

Tomoyasu Kitano

Daisuke Ichigosaki

A manufacturing method of a rare-earth magnet includes: manufacturing a sintered body having by performing pressing on a magnetic powder for a rare-earth magnet; and manufacturing a rare-earth magnet by putting the sintered body in a plastic working mold and by performing hot plastic working on the sintered body while pressing the sintered body to give anisotropy to the sintered body. The sintered body has a cuboid shape and includes at least one recessed side face that has a recessed portion curved inward. The plastic working mold includes a lower die, a side die forming a rectangular frame of four side faces, and an upper die slidable in the side die. The hot plastic working is hot upsetting.

Manufacturing method of rare-earth magnet

Provided is a method for manufacturing a rare-earth magnet capable of manufacturing a rare-earth magnet with high degree of orientation by sufficient plastic deformation while suppressing cracks at the side faces of a compact that is plastic-deformed during the hot deformation processing. The method includes a step of preparing a compact S, preparing a plastic processing mold including a die D in which a cavity Ca is provided, and punches P that are slidable in the cavity Ca, the cavity Ca having a cross section that is larger in cross-sectional dimensions than a cross section of the compact S that is orthogonal to a pressing direction by the punches P; and a step of placing the compact S in the cavity Ca and performing hot deformation processing, thus manufacturing an orientational magnet C. Let that Wdenotes a length of a short side of the cross section of the cavity Ca and tdenotes a length of a side of the cross section of the compact S that is placed in the cavity Ca, the side corresponding to the short side of the cavity Ca, t/Wis within a range of 0.55 to 0.85, and from some stage during the hot deformation processing, a part of the compact S is constrained at a side face of the cavity Ca so that deformation of the compact is suppressed, but another part of the compact is in a non-constraint state.

Manufacturing method for rare-earth magnet

A production method includes producing a rare-earth magnet precursor (S') by performing first hot working in which, in two side surfaces of a sintered body, which are parallel to a pressing direction and are opposite to each other, one side surface is brought to a constrained state to suppress deformation, and the other side surface is brought to an unconstrained state to permit deformation; and producing a rare-earth magnet by performing second hot working in which, in two side surfaces (S&#x2032;, S&#x2032;) of the rare-earth magnet precursor (S&#x2032;), which are parallel to the pressing direction, a side surface (S&#x2032;), which is in the unconstrained state in the first hot working, is brought to the constrained state to suppress deformation, and a side surface (S&#x2032;), which is in the constrained state in the first hot working, is brought to the unconstrained state to permit deformation.

Method of production rare-earth magnet

An iron powder for dust cores is provided which can be formed into a dust core having a high resistivity and having a low iron loss without degrading the mechanical strength. The iron powder for dust cores includes an iron powder and an oxide film on the surface thereof, wherein the oxide film is composed of a Si-based oxide in which the ratio of Si to Fe satisfies Si/Fe&#x2267;0.8 on an atomic number basis.

Iron powder for dust cores

A method for manufacturing a powder for a magnetic core including at least a process of performing a siliconizing treatment on a surface of an iron powder containing elemental carbon. In the process of siliconizing treatment, a powder containing at least a silicon dioxide is brought into contact with the surface of the iron powder, elemental silicon is detached from the silicon dioxide by heating the powder of silicon dioxide, and the siliconizing treatment is performed by causing the detached elemental silicon to permeate and diffuse into a surface layer of the iron powder. The invention provides a method for manufacturing a powder for a magnetic core, by which loss reduction is achieved.

Powder for magnetic core, method for manufacturing powder for magnetic core, and dust core

A powder for a dust core comprising a silicon-containing layer formed within a depth of less than 0.15 D from the surface of the surface layer of a soft magnetic metal powder having a particle diameter D and a method for producing the same are provided. The method for producing a powder for a dust corecomprising a silicon-containing layercomprises performing silicon impregnation of the surface of a soft magnetic metal powder (particle)containing a carbon element, wherein:

Powder for dust core and method for producing the same

In a stator core composed of a powder compacted magnetic body, a yoke part comprises a protrusion protruding from an axial end face of a tooth. The tooth has an axial length gradually decreases towards an outside along the radial direction of the stator core, and a circumferential length which gradually increases towards an outside along the radial direction of the stator core. In one of the cross sections of stator core perpendicular to a radial direction, the height difference between axial end faces of the yoke part and the tooth is substantially equal to an axial length of a coil end part. Further, a cross-sectional area of the tooth perpendicular to the radial direction is substantially maintained constant along the radial direction, and the cross-sectional area is secured at a junction between the tooth and the yoke part, while half of the cross-sectional area is secured in a circumferential cross section of the yoke part.

Motor generator and automobile carrying the same

A core comprises a plurality of core split members having yoke portions and tooth portions and arranged in such a circumferential shape that the yoke portions contact with each other while the tooth portions being directed inward. The core further comprises a ring contacting with the yoke portions, and stoppers mounted on the outer face sides of the yoke portions for fixing the ring on the yoke portions. The yoke portions and the ring are formed in corrugated shape to mesh with each other, and the stoppers are formed with projections that engage with the inner side of the ring. This structure provides both the rotating electrical machine core having the core split members arranged in the circumferential shape and fastened to each other while preventing occurrence of a stress and a positional displacement between the core split members, and a rotating electrical machine.

Rotating electrical machine core and rotating electrical machine

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Toyota, Japan

Eisuke Hoshina