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Heavy Rare Earth-free Hot-deformed Magnet for Traction Motor

Article of Honda R&D Technical Review Vol.28 No.2


A technology has been developed making it possible to do away with the use of the heavy rare earths dysprosium and terbium, which are added to the magnets employed in traction motors for application in electric vehicles and hybrid electric vehicles in order to increase heat resistance. The research focused on the hot-deformation method of magnet manufacture, which offers greater potential for the realization of heat resistance than the sintering method, the main method of manufacturing the magnets currently in use. The magnetic properties of the developed magnet were boosted by reduction of the temperature for hot-deformation and the optimization of the rate of hot-deformation and the composition design of the magnet material. These approaches made it possible to develop a completely heavy rare earth-free magnet able to be employed in mass-production vehicles.


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Author (organization or company)

Haruhiko SHIMIZU(Automobile R&D Center)、Ryutaro KATO(Automobile R&D Center)、Yoshiyuki NAKAZAWA(Automobile R&D Center)、Atsushi HATTORI(Daido Steel Co., Ltd.)、Keiko HIOKI(Daido Steel Co., Ltd.)、Takashi OIKAWA(Daido Steel Co., Ltd.)

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