公开(公告)号：US10770207B2

公开(公告)日：2020-09-08

申请号：US14233286

申请日：2013-03-08

Applicant: NITTO DENKO CORPORATION

Inventor： Katsuya Kume ,  Toshiaki Okuno ,  Izumi Ozeki ,  Tomohiro Omure ,  Takashi Ozaki ,  Keisuke Taihaku ,  Takashi Yamamoto

IPC: H01F1/053 ,  B22F1/00 ,  H01F1/057 ,  H01F1/08 ,  B22F3/18 ,  B22F7/04 ,  C22C38/00 ,  H01F41/02

Abstract: There are provided a rare-earth permanent magnet and a manufacturing method of a rare-earth permanent magnet capable of preventing deterioration of magnet properties. In the method, magnet material is milled into magnet powder. Next, a mixture 12 is prepared by mixing the magnet powder and a binder, and the mixture 12 is formed into a sheet-like shape to obtain a green sheet 14. Thereafter, magnetic field orientation is performed to the green sheet 14, which is then held for several hours in a non-oxidizing atmosphere at a pressure higher than normal atmospheric pressure, at 200 through 900 degrees Celsius for calcination. Thereafter, the calcined green sheet 14 is sintered at a sintering temperature. Thereby a permanent magnet 1 is manufactured.

公开(公告)号：US10269475B2

公开(公告)日：2019-04-23

申请号：US15118116

申请日：2014-02-12

Applicant: NITTO DENKO CORPORATION

Inventor： Izumi Ozeki ,  Katsuya Kume ,  Toshiaki Okuno ,  Takashi Ozaki ,  Tomohiro Omure ,  Keisuke Taihaku ,  Takashi Yamamoto

IPC: H01F41/02 ,  H01F1/053 ,  C22C38/00 ,  B22F3/10 ,  B22F3/22 ,  B22F5/00 ,  B22F9/04 ,  C22C1/04 ,  H01F1/057 ,  C22C33/02

Abstract: Provided are a rare-earth permanent magnet whose magnet density after sintering is very high and a method for manufacturing a rare-earth permanent magnet. Thus, a magnet raw material is milled into magnet powder, and then, a compound 12 is formed by mixing the magnet powder thus milled with a binder. Next, the compound 12 thus formed is subjected to a hot-melt molding onto a supporting substrate 13 so as to form a green sheet 14 molded to a sheet-like shape. Thereafter, while the green sheet 14 thus molded is softened by heating, magnetic field orientation is carried out by applying a magnetic field to the green sheet 14 thus heated; and further, the green sheet 14 having been subjected to the magnetic field orientation is calcined by a vacuum sintering, which is further followed by a pressure sintering to produce a permanent magnet 1.