Manufacturing method of rare-earth magnet

Patent metadata

Field	Value
Publication number	US-10062504-B2
Application number	US-201514833548-A
Country	US
Kind code	B2
Filing date	Aug 24, 2015
Priority date	Aug 25, 2014
Publication date	Aug 28, 2018
Grant date	Aug 28, 2018

Abstract

A manufacturing method of a rare-earth magnet includes: manufacturing a first sealing body by filling a graphite container with a magnetic powder to be a rare-earth magnet material and by sealing the graphite container; manufacturing a sintered body by sintering the first sealing body to manufacture a second sealing body in which the sintered body is accommodated; and manufacturing a rare-earth magnet by performing hot plastic working on the second sealing body to give magnetic anisotropy to the sintered body.

First claim

What is claimed is:

1. A manufacturing method of a rare-earth magnet, comprising:
manufacturing a first sealing body by filling a first graphite container with a magnetic powder to be a rare-earth magnet material, then inserting an open end of the first graphite container into an open end of a second graphite container to form a third graphite container, and sealing the third graphite container, wherein the third graphite container is constituted by the first graphite container and the second graphite container;
manufacturing a sintered body by sintering the first sealing body to manufacture a second sealing body in which the sintered body is accommodated; and
manufacturing a rare-earth magnet by performing hot plastic working on the second sealing body to give magnetic anisotropy to the sintered body,
wherein an inside dimension of the second graphite container is larger than an inside dimension of the first graphite container,
each of the first graphite container and the second graphite container is a tube-shaped body constituted by a deformed graphite sheet and having a rectangular section or a circular section, and
the tube-shaped body has a closed end provided with a graphite base plate;
the method further comprising:
forming the tube-shaped body by deforming a graphite sheet along a side surface of a tube-shaped stand, the side surface having a rectangular section or a circular section, the tube-shaped stand including a bottom face provided on an end surface of the side surface, and the bottom face having a through-hole;
filling graphite powder into the tube-shaped stand by moving the tube-shaped stand relative to the tube-shaped body; and
forming the base plate on an open end of the tube-shaped body by pushing the tube-shaped stand downward to perform press molding on the graphite powder after the graphite powder falls down below the bottom face of the tube-shaped stand through the through-hole.

2. The manufacturing method of a rare-earth magnet according to claim 1 , further comprising
manufacturing the graphite base plate by performing press molding on graphite powder filled into the tube-shaped body.

3. A manufacturing method of a rare-earth magnet, comprising:
manufacturing a first sealing body by filling a graphite container with a magnetic powder to be a rare-earth magnet material, disposing a graphite top plate on an open end of the graphite container, and sealing the graphite container;
manufacturing a sintered body by sintering the first sealing body to manufacture a second sealing body in which the sintered body is accommodated; and
manufacturing a rare-earth magnet by performing hot plastic working on the second sealing body to give magnetic anisotropy to the sintered body;
wherein the graphite container is a tube-shaped body constituted by a deformed graphite sheet and having a rectangular section or a circular section, and the tube-shaped body has a closed end provided with a graphite base plate;
the method further comprising:
forming the tube-shaped body by deforming a graphite sheet along a side surface of a tube-shaped stand, the side surface having a rectangular section or a circular section, the tube-shaped stand including a bottom face provided on an end surface of the side surface, and the bottom face having a through-hole;
filling graphite powder into the tube-shaped stand by moving the tube-shaped stand relative to the tube-shaped body; and
forming the base plate on an open end of the tube-shaped body by pushing the tube-shaped stand downward to perform press molding on the graphite powder after the graphite powder falls down below the bottom face of the tube-shaped stand through the through-hole.

4. The manufacturing method of a rare-earth magnet according to claim 3 , further comprising
manufacturing the graphite top plate by performing press molding on graphite powder.

Assignees

• Toyota Motor Co Ltd

Inventors

• Haga Kazuaki
• Ueno Noriyuki
• Kano Akira
• Inuzuka Tomonori
• Sakuma Noritsugu

Classifications

• B22F3/1216

  Container composition · CPC title

• B22F3/1258

  Container manufacturing · CPC title

• H01F1/086

  sintered · CPC title

• B22F2999/00

  Aspects linked to processes or compositions used in powder metallurgy · CPC title

• B22F3/17

  by forging · CPC title