Magnet and motor using the same

Patent metadata

Field	Value
Publication number	US-10964464-B2
Application number	US-201816194521-A
Country	US
Kind code	B2
Filing date	Nov 19, 2018
Priority date	Nov 24, 2017
Publication date	Mar 30, 2021
Grant date	Mar 30, 2021

Abstract

The present invention aims to provide a novel magnet, whose surface's insulating property can be increased, and a motor using the same. The present invention provides a magnet comprising a magnet element containing a rare earth element R, a transition metal element T and boron B, and a phosphate layer including manganese-containing phosphate, wherein the phosphate layer is provided on the surface of the magnet element, and the thickness of the phosphate layer is 0.5 μm or more.

First claim

What is claimed is:

1. A magnet comprising:
a magnet element containing a rare earth element R, a transition metal element T and boron B; and
a phosphate layer including manganese-containing phosphate;
wherein the phosphate layer is provided on a surface of the magnet element, and a thickness of the phosphate layer is 0.5 μm or more and 5.0 μm or less,
wherein the surface of the magnet element has a main phase comprising a plurality of R 2 T 14 B crystal grains and a grain boundary phase arranged among the R 2 T 14 B crystal grains, and
the phosphate layer covers the main phase of the magnet element and does not cover the grain boundary phase of the magnet element.

2. A motor comprising:
a rotor having a core and two or more magnets; and
a stator;
wherein at least one of the magnets is the magnet according to claim 1 .

3. A motor comprising:
a rotor having a core and two or more magnets; and
a stator;
wherein at least one of the magnets is the magnet according to claim 1 ,
the core has slits, and
a plurality of the magnets according to claim 1 are arranged in each of the slits.

Assignees

• Tdk Corp

Inventors

• Takagi Nobuo

Classifications

• H02K1/02 Primary

  characterised by the magnetic material · CPC title

• H01F41/026

  protecting methods against environmental influences, e.g. oxygen, by surface treatment (magnetic particles with skin H01F1/061, H01F1/09, H01F1/24, H01F1/33 and G11B5/706) · CPC title

• H02K1/276

  Magnets embedded in the magnetic core, e.g. interior permanent magnets [IPM] · CPC title

• H01F41/0293

  diffusion of rare earth elements, e.g. Tb, Dy or Ho, into permanent magnets · CPC title

• H01F1/0577 Primary

  sintered · CPC title