Powder magnetic core and magnetic element using the same

• US 8,366,837 B2
• Filed: 01/14/2010
• Issued: 02/05/2013
• Est. Priority Date: 03/09/2009
• Status: Active Grant

• Current Assignee: Panasonic Corporation (Panasonic Holdings Corporation)
• Original Assignee: Panasonic Corporation (Panasonic Holdings Corporation)
• Inventors: Wakabayashi, Yuya, Takahashi, Takeshi, Matsutani, Nobuya
• Primary Examiner(s): SHEEHAN, JOHN P
• Application Number:
  US13/255,615
• Publication Number:
  US 20120001710A1
• Time in Patent Office: 1,118 Days
• Field of Search: None
• US Class Current: 148/306
• CPC Class Codes: B22F 1/102 Metallic powder coated with organic material
• CPC Class Codes: B22F 1/105 containing inorganic lubricating or binding agents, e.g. metal salts
• CPC Class Codes: B22F 1/16 Metallic particles coated with a non-metal coated with lubricating or binding agents or with organic material B22F1/10
• CPC Class Codes: C22C 1/02 by melting C22C1/1036 takes precedence
• CPC Class Codes: C22C 19/03 based on nickel
• CPC Class Codes: C22C 30/00 Alloys containing less than 50% by weight of each constituent
• CPC Class Codes: C22C 33/0228 comprising other non-metallic compounds or more than 5% of graphite
• CPC Class Codes: C22C 38/02 containing silicon
• CPC Class Codes: C22C 38/06 containing aluminium
• CPC Class Codes: C22C 38/08 containing nickel C22C38/105 takes precedence
• CPC Class Codes: C22C 38/34 with more than 1.5% by weight of silicon
• CPC Class Codes: H01F 1/24 the particles being insulated
• CPC Class Codes: H01F 1/26 by macromolecular organic substances
• CPC Class Codes: H01F 2017/048 with encapsulating core, e.g. made of resin and magnetic powder
• CPC Class Codes: H01F 41/0246 Manufacturing of magnetic circuits by moulding or by pressing powder magnetic cores made by moulding or by pressing powder H01F27/255; soft magnetic particles H01F1/20, H01F1/36
• CPC Class Codes: Y10T 428/256 Heavy metal or aluminum or compound thereof

Abstract

The invention can provide a dust core that can counteract a large electric current, achieve an increase in frequency and miniaturization, and achieve an improvement in voltage resistance, and a magnetic element using the same. The dust core of the invention is a dust core including metallic magnetic powder, an inorganic insulating material, and a thermosetting resin, in which the metallic magnetic powder has a Vickers hardness (Hv) in a range of 230≦Hv≦1000, the inorganic insulating material has a compressive strength of 10000 kg/cm² or lower and is in a mechanical collapse state, and the inorganic insulating material in a mechanical collapse state and the thermosetting resin are interposed between the metallic magnetic powder particles.

Claims

1. A dust core comprising a metallic magnetic powder, an inorganic insulating material, and a thermosetting resin,

wherein the metallic magnetic powder has a Vickers hardness (Hv) in a range of 230≦

Hv≦

1000,

the inorganic insulating material has a compressive strength of 10000 kg/cm² or lower and is in a mechanical collapse state, and

the inorganic insulating material in a mechanical collapse state and the thermosetting resin are interposed between the metallic magnetic powder particles.

2. The dust core of claim 1,

wherein the metallic magnetic powder includes at least one kind of Fe—

Ni-based, Fe—

Si—

Al-based, Fe—

Si-based, Fe—

Si—

Cr-based, and other Fe-based metallic magnetic powder.

3. The dust core of claim 1,

wherein the average particle diameter of the metallic magnetic powder is 1 μ

m to 100 μ

m.

4. The dust core of claim 1,

wherein 1% by volume to 15% by volume of the inorganic insulating material is mixed with respect to 100% by volume of the metallic magnetic powder.

5. The dust core of claim 1,

wherein the packing factor of the metallic magnetic powder is 65% to 82% by volume conversion.

6. The dust core of claim 1,

wherein the electrical resistivity is 10⁵ Ω

·

cm or higher.

7. A magnetic element having a coil buried in the dust core of claim 1.