Sintered ferrite magnet

Patent metadata

Field	Value
Publication number	US-11289250-B2
Application number	US-201816611517-A
Country	US
Kind code	B2
Filing date	May 17, 2018
Priority date	May 24, 2017
Publication date	Mar 29, 2022
Grant date	Mar 29, 2022

Abstract

A sintered ferrite magnet represented by the general formula of Ca1-xLaxFe2n-y-zCoyZnz expressing the atomic ratios of metal elements of Ca, La, Fe, Co and Zn, wherein x, y, z, and n [2n is a molar ratio represented by 2n=(Fe+Co+Zn)/(Ca+La)] meet 0.4<x<0.75, 0.15≤y<0.4, 0.11≤z<0.4, 0.26≤(y+z)<0.65, and 3≤n≤6.

First claim

What is claimed is:

1. A sintered ferrite magnet represented by the general formula of Ca 1-x La x Fe 2n-y-z Co y Zn z expressing the atomic ratios of metal elements of Ca, La, Fe, Co and Zn, wherein x, y, z, and n [2n is a molar ratio represented by 2n=(Fe+Co+Zn)/(Ca+La)] meet
0.4<x<0.75,
0.15≤y≤0.20,
0.25≤z<0.4,
0.40≤(y+z)<0.6, and
3≤n≤6,
wherein 0-0.45% by mass of Si calculated as SiO 2 is contained, and
wherein the sintered ferrite magnet has a remanence B r of 0.465 T or higher.

2. The sintered ferrite magnet according to claim 1 , wherein said y and z meet 0.15≤y≤0.20, and 0.25≤z≤0.35.

3. The sintered ferrite magnet according to claim 1 , wherein said x meets 0.475≤x≤0.7.

4. The sintered ferrite magnet according to claim 1 , wherein said y and z meet 0.40≤(y+z)≤0.55.

5. The sintered ferrite magnet according to claim 1 , wherein said x meets 0.55≤x≤0.7.

6. The sintered ferrite magnet according to claim 1 , wherein said x meets 0.6≤x≤0.7.

7. The sintered ferrite magnet according to claim 1 , wherein said y and z meet 0.40≤(y+z)≤0.5.

8. The sintered ferrite magnet according to claim 1 , wherein said y and z meet 0.40≤(y+z)≤0.45.

9. A sintered ferrite magnet represented by the general formula of Ca 1-x La x Fe 2n-y-z Co y Zn z expressing the atomic ratios of metal elements of Ca, La, Fe, Co and Zn, wherein x, y, z, and n [2n is a molar ratio represented by 2n=(Fe+Co+Zn)/(Ca+La)] meet
0.4<x<0.75,
0.15≤y≤0.20,
0.25≤z<0.4,
0.40≤(y+z)<0.6, and
3≤n≤6,
wherein part of La is substituted by at least one of rare earth elements excluding La in the above general formula,
wherein 0-0.45% by mass of Si calculated as SiO 2 is contained, and
wherein the sintered ferrite magnet has a remanence B r of 0.465 T or higher.

10. The sintered ferrite magnet according to claim 9 , wherein 50% or less by mol of La is substituted by at least one of rare earth elements excluding La in the above general formula.

11. The sintered ferrite magnet according to claim 9 , wherein said y and z meet 0.15≤y≤0.20, and 0.25≤z≤0.35.

12. The sintered ferrite magnet according to claim 9 , wherein said x meets 0.475≤x≤0.7.

13. The sintered ferrite magnet according to claim 9 , wherein said x meets 0.55≤x≤0.7.

14. The sintered ferrite magnet according to claim 9 , wherein said x meets 0.6≤x≤0.7.

15. The sintered ferrite magnet according to claim 9 , wherein said y and z meet 0.40≤(y+z)≤0.55.

16. The sintered ferrite magnet according to claim 9 , wherein said y and z meet 0.40≤(y+z)≤0.5.

17. The sintered ferrite magnet according to claim 9 , wherein said y and z meet 0.40≤(y+z)≤0.45.

18. A sintered ferrite magnet represented by the general formula of Ca 1-x La x Fe 2n-y-z Co y Zn z expressing the atomic ratios of metal elements of Ca, La, Fe, Co and Zn, wherein x, y, z, and n [2n is a molar ratio represented by 2n=(Fe+Co+Zn)/(Ca+La)] meet
0.4<x<0.75,
0.15≤y≤0.18,
0.20≤z<0.4,
0.35≤(y+z)<0.58, and
3≤n≤6,
wherein 0-0.45% by mass of Si calculated as SiO 2 is contained, and
wherein the sintered ferrite magnet has a remanence Br of 0.465 T or higher.

19. A sintered ferrite magnet represented by the general formula of Ca 1-x La x Fe 2n-y-z Co y Zn z expressing the atomic ratios of metal elements of Ca, La, Fe, Co and Zn, wherein x, y, z, and n [2n is a molar ratio represented by 2n=(Fe+Co+Zn)/(Ca+La)] meet
0.4<x<0.75,
0.15≤y≤0.18,
0.20≤z<0.4,
0.35≤(y+z)<0.58, and
3≤n≤6,
wherein part of La is substituted by at least one of rare earth elements excluding La in the above general formula,
wherein 0-0.45% by mass of Si calculated as SiO 2 is contained, and
wherein the sintered ferrite magnet has a remanence Br of 0.465 T or higher.

Assignees

• Hitachi Metals Ltd

Inventors

• Yamamoto Masaki
• Kobayashi Yoshinori

Classifications

• C01G51/70

  containing rare earths, e.g. LaCoO3  (C01G51/68 takes precedence) · CPC title

• H01F1/10 Primary

  non-metallic substances, e.g. ferrites {, e.g. [(Ba,Sr)O(Fe2O3)6] ferrites with hexagonal structure} · CPC title

• C01G49/00

  Compounds of iron · CPC title

• C01G49/009

  Compounds containing iron, with or without oxygen or hydrogen, and containing two or more other elements · CPC title

• C01P2002/52

  containing elements as dopants · CPC title