Resin-bonded magnet, its product, and ferrite magnet powder and compound used therefor

• US 6,537,463 B2
• Filed: 12/11/2000
• Issued: 03/25/2003
• Est. Priority Date: 03/12/1999
• Status: Expired due to Fees

• Current Assignee: Hitachi Metals (Thailand) Ltd.
• Original Assignee: Hitachi Metals (Thailand) Ltd.
• Inventors: Tobise, Masahiro, Iwasaki, Katsunori, Okajima, Hiroshi, Shindo, Mikio, Ogata, Yasunobu
• Primary Examiner(s): Koslow, C. Melissa
• Application Number:
  US09/732,744
• Publication Number:
  US 20020084001A1
• Time in Patent Office: 834 Days
• Field of Search: 252/62.63, 252/62.57, 252/62.55, 252/62.54, 252/62.59, 248/301
• US Class Current: 252/62.54
• CPC Class Codes: H01F 1/059 and Va elements, e.g. Sm2Fe17N2
• CPC Class Codes: H01F 1/09 mixtures of metallic and non-metallic particles; metallic particles having oxide skin
• CPC Class Codes: H01F 7/0268 Magnetic cylinders

Abstract

A resin-bonded magnet composed substantially of (a) an R—T—N-based magnetic powder having a basic composition of R_αT_{100−α−β}N_β, wherein R is at least one selected form the group consisting of rare earth elements including Y, T is Fe or Fe and Co, 5≦α≦20, and 5≦β≦30, (b) a ferrite magnetic powder having a substantially magnetoplumbite-type crystal structure and a basic composition represented by (A_1−xR′_x) O[(Fe_1−yM_y)₂O₃] by atomic ratio, wherein A is Sr and/or Ba, R′ is at least one selected from the group consisting of rare earth elements including Y, La being indispensable, M is Co or Co and Zn, 0.01≦x<0.4, 0.005≦y≦0.04, and 5.0≦n≦6.4, and (c) a binder. The ferrite magnet powder is preferably an anisotropic, granulated powder or an anisotropic, sintered ferrite magnet powder.

Claims

1. A ferrite magnet powder for resin-bonded magnets comprising powder obtained by disintegrating a sintered ferrite magnetic material, said sintered ferrite magnet powder having a substantially magnetoplumbite-type crystal structure and a basic composition represented by the following general formula:

2. The ferrite magnet powder for resin-bonded magnets according to claim 1, wherein said sintered ferrite magnet powder contains SiO₂ and CaO in amounts of 0.05-0.55% by weight and 0.35-1% by weight, respectively, based on 100% by weight of the sintered ferrite magnet powder.

3. The ferrite magnet powder for resin-bonded magnets according to claim 1 or 2, wherein said ferrite magnet powder has an average particle size of 2-300 μ

m and is used for molding in a magnetic field.

4. A compound for resin-bonded magnets composed substantially of:

(a) an R—

T—

N-based magnet powder having a basic composition of R_α

T<sub>100−

α

−

β</sub>

N_β

, wherein R is at least one member selected from the group consisting of rare earth elements including Y;

T is Fe or Fe and Co; and

α and

β

satisfy 5≦

α

≦

20 and 5≦

β

≦

30, respectively, by atomic %,

(b) a ferrite magnetic powder for resin-bonded magnets comprising powder obtained by disintegrating a sintered ferrite magnetic material, said sintered ferrite magnetic powder having a substantially magnetoplumbite-type crystal structure and a basic composition represented by the following general formula;

5. The compound for resin-bonded magnets according to claim 4, wherein said R—

T—

N-based magnet powder has an average particle size of 1-10 μ

m and said ferrite magnet powder has an average particle size of 0.9-2 μ

m.

6. A compound for resin-bonded magnets composed substantially of:

(a) an R—

T—

N-based magnetic powder having a basic composition of R_α

T<sub>100−

α

β</sub>

N_β

, wherein R is at least one element selected from the group consisting of rare earth elements including Y;

T is Fe, or Fe and Co;

α and

β

satisfy 5≦

α

≦

20 and 5≦

β

≦

30, respectively, by atomic %,

(b) a ferrite magnetic powder for resin-bonded magnets comprising powder obtained by disintegrating a sintered ferrite magnetic material, said sintered ferrite magnetic powder having a substantially magnetoplumbite-type crystal structure and a basic composition represented by the following general formula;

7. A compound for resin-bonded magnets, composed substantially of:

(a) an R—

T—

N-based magnetic powder having a basic composition of R_α

T<sub>100−

α

−

β</sub>

N_β

, wherein R is at least one element selected from the group consisting of rare earth elements including Y;

T is Fe, or Fe and Co;

α and

β

satisfy 5≦

α

≦

20 and 5≦

β

≦

30, respectively, by atomic %,

(b) a ferrite magnetic powder for resin-bonded magnets comprising powder obtained by disintegrating a sintered ferrite magnetic material, said sintered ferrite magnetic powder having a substantially magnetoplumbite-type crystal structure and a basic composition represented by the following general formula;

8. A resin-bonded magnet composed substantially of:

(a) an R—

T—

N-based magnet powder having a basic composition of R_α

T<sub>100−

α

−

β</sub>

N_β

, wherein R is at least one element selected from the group consisting of rare earth elements including Y;

T is Fe or Fe and Co; and

α and

β

satisfy 5≦

α

≦

20 and 5≦

β

≦

30, respectively, by atomic %,

(b) a ferrite magnetic powder for resin-bonded magnets comprising powder obtained by disintegrating a sintered ferrite magnetic material, said sintered ferrite magnetic powder having a substantially magnetoplumbite crystal structure and a basic composition represented by the following general formula;

9. The resin-bonded magnet according to claim 8, wherein said R—

T—

N-based magnet powder has an average particle size of 1-10 μ

m, and said ferrite magnet powder is an anisotropic, granulated powder or an anisotropic sintered magnet powder, each having an average particle size of 2-300 μ

m.

10. The resin-bonded magnet according to claim 8, wherein said R—

T—

N-based magnet powder has an average particle size of 1-10 μ

m, and said ferrite magnet powder is an anisotropic, granulated powder and whose magnet has anisotropy imparted during molding in a magnetic field.

11. The resin-bonded magnet according to claim 8, wherein said R—

T—

N-based magnet powder has an average particle size of 1-10 μ

m, and said ferrite magnet powder is an anisotropic, sintered ferrite magnet powder and whose magnet has anisotropy imparted during molding in a magnetic field.

12. The resin-bonded magnet according to any one of claims 8-11, which has a ring shape, a cylindrical shape or an arc-segment shape.

13. The resin-bonded magnet according to any one of claims 8-11, which has radial or polar anisotropy.

14. A rotor constituted by a resin-bonded magnet composed substantially of:

(a) an R—

T—

N-based magnet powder having a basic composition of R_α

T<sub>100−

α

−

β</sub>

N_β

, wherein R is at least one element selected from the group consisting of rare earth elements including Y;

T is Fe or Fe and Co; and

α and

β

satisfy 5≦

α

≦

20 and 5≦

β

≦

30, respectively, by atomic %,

(b) a ferrite magnetic powder for resin-bonded magnets comprising powder obtained by disintegrating a sintered ferrite magnetic material, said sintered ferrite magnetic powder having a substantially magnetoplumbite crystal structure and a basic composition represented by the following general formula;

15. The rotor according to claim 14, wherein said R—

T—

N-based magnet powder has an average particle size of 1-10 μ

m, and said ferrite magnet powder is an anisotropic, granulated powder or an anisotropic, sintered ferrite magnet powder.

16. A magnet roll constituted by a resin-bonded magnet composed substantially of:

(a) an R—

T—

N-based magnet powder having a basic composition of R_α

T<sub>100−

α

−

β</sub>

N_β

, wherein R is at least one element selected from the group consisting of rare earth elements including Y;

T is Fe or Fe and Co; and

α and

β

satisfy 5≦

α

≦

20 and 5≦

β

≦

30, respectively, by atomic %,

(b) a ferrite magnetic powder for resin-bonded magnets comprising powder obtained by disintegrating a sintered ferrite magnetic material, said sintered ferrite magnetic powder having a substantially magnetoplumbite crystal structure and a basic composition represented by the following general formula;

17. The magnet roll according to claim 16, wherein said R—

T—

N-based magnet powder has an average particle size of 1-10 μ

m, and said ferrite magnet powder is an anisotropic, granulated powder or an anisotropic, sintered ferrite magnet powder.