Soft magnetic alloy powder, dust core, and coil component

Patent metadata

Field	Value
Publication number	US-11996220-B2
Application number	US-202217879862-A
Country	US
Kind code	B2
Filing date	Aug 3, 2022
Priority date	Aug 6, 2021
Publication date	May 28, 2024
Grant date	May 28, 2024

Abstract

A soft magnetic alloy powder contains soft magnetic alloy particles. The soft magnetic alloy particles contain Fe and Si. The soft magnetic alloy particles each include crystal grains and crystal grain boundary between the crystal grains. At least one of the crystal grains has a Si segregation part.

First claim

What is claimed is:

1. A soft magnetic alloy powder comprising soft magnetic alloy particles, wherein
the soft magnetic alloy particles consist of Fe, Si, and inevitable impurities,
an amount of Si in the soft magnetic alloy particles is 3.0 mass % or more and 11.0 mass % or less,
the soft magnetic alloy particles include crystal grains and a crystal grain boundary between the crystal grains,
an average particle size of the soft magnetic alloy particles is 1 μm or more and 50 μm or less,
at least one of the crystal grains has a Si segregation part,
the Si segregation part is a part having a Si concentration of 105% or more with respect to an average Si concentration of the soft magnetic alloy particles,
the Si segregation part exists in both the crystal grain boundary and at least one of the crystal grains, and
a size of one Si segregation part is 0.4 μm 2 or more.

2. A dust core comprising the soft magnetic alloy powder according to claim 1 .

3. A coil component comprising the dust core according to claim 2 .

4. The soft magnetic alloy powder according to claim 1 , wherein Ni is contained in an amount of 5.0 mass % or less.

5. The soft magnetic alloy powder according to claim 1 , wherein Ni is contained in an amount of 0.5 mass % or less.

6. The soft magnetic alloy powder according to claim 1 , wherein a total amount of the inevitable impurities is 2.0 mass % or less.

7. The soft magnetic alloy powder according to claim 1 , wherein a total amount of the inevitable impurities is 1.0 mass % or less.

8. The soft magnetic alloy powder according to claim 1 , wherein the Si segregation part is present in a net-like structure in the crystal grain.

9. The soft magnetic alloy powder according to claim 1 , wherein a total area of the Si segregation parts in the crystal grains is 5% or more of the total area of the crystal grains.

10. The soft magnetic alloy powder according to claim 1 , wherein a content ratio of the soft magnetic alloy particles including the Si segregation parts in the crystal grains is 50% or more based on the number of particles.

11. A soft magnetic alloy powder comprising soft magnetic particles, wherein
the soft magnetic alloy particles consist of Fe, Si, and inevitable impurities,
an amount of Si in the soft magnetic alloy particles is 3.0 mass % or more and 11.0 mass % or less,
the soft magnetic alloy particles include crystal grains and a crystal grain boundary between the crystal grains,
an average crystal grain size of the soft magnetic alloy particles is 0.5 μm or more and 20 μm or less,
at least one of the crystal grains has a Si segregation part,
the Si segregation part is a part having a Si concentration of 105% or more with respect to an average Si concentration of the soft magnetic alloy particles,
the Si segregation part exists in both the crystal grain boundary and at least one of the crystal grains, and
a size of one Si segregation part is 0.4 μm 2 or more.

12. A dust core comprising the soft magnetic alloy powder according to claim 11 .

13. A coil component comprising the dust core according to claim 12 .

14. The soft magnetic alloy powder according to claim 11 , wherein Ni is contained in an amount of 5.0 mass % or less.

15. The soft magnetic alloy powder according to claim 11 , wherein Ni is contained in an amount of 0.5 mass % or less.

16. The soft magnetic alloy powder according to claim 11 , wherein a total amount of the inevitable impurities is 2.0 mass % or less.

17. The soft magnetic alloy powder according to claim 11 , wherein a total amount of the inevitable impurities is 1.0 mass % or less.

18. The soft magnetic alloy powder according to claim 11 , wherein the Si segregation part is present in a net-like structure in the crystal grain.

19. The soft magnetic alloy powder according to claim 11 , wherein a total area of the Si segregation parts in the crystal grains is 5% or more of the total area of the crystal grains.

20. The soft magnetic alloy powder according to claim 11 , wherein a content ratio of the soft magnetic alloy particles including the Si segregation parts in the crystal grains is 50% or more based on the number of particles.

Assignees

• Tdk Corp

Inventors

• Yasuhara Katsushi
• Nakazawa Ryoma
• Taniguchi Yusuke
• Ono Hiroyuki

Classifications

• H01F1/14766 Primary

  Fe-Si based alloys · CPC title

• B22F1/052

  characterised by a mixture of particles of different sizes or by the particle size distribution · CPC title

• C22C38/02 Primary

  containing silicon · CPC title

• H01F1/20 Primary

  in the form of particles, e.g. powder (H01F1/147 takes precedence) · CPC title

• H01F3/08

  made from powder (powder coatings on sheets H01F3/02; on strips or ribbons H01F3/04; on wires H01F3/06) · CPC title