Magnetic material and production method therefor

Patent metadata

Field	Value
Publication number	US-11056258-B2
Application number	US-201615547681-A
Country	US
Kind code	B2
Filing date	Jan 28, 2016
Priority date	Feb 4, 2015
Publication date	Jul 6, 2021
Grant date	Jul 6, 2021

Abstract

A production method for a magnetic material, which is expressed by a chemical structure formula Fe(Al1-xMnx)2O4, where 0<x<1, and exhibits ferromagnetism, includes: preparing a mixed aqueous solution by dissolving, in distilled water, Fe nitrate, Al nitrate, and an oxide including Mn, the Fe nitrate, the Al nitrate, and the oxide being parent materials; preparing a metal-citric acid complex by mixing citric acid and ethylene glycol with the mixed aqueous solution; obtaining a precursor by boiling the metal-citric acid complex to a gel and drying the gel; and obtaining the magnetic material by sintering the precursor.

First claim

The invention claimed is:

1. A magnetic material which is expressed by a chemical structure formula Fe(Al 1-x Mn x ) 2 O 4 , where x is ≥0.2 and x is <1, and exhibits ferromagnetism.

2. The magnetic material according to claim 1 ,
wherein a range of a value of mass magnetic susceptibility σ s [emu/g] of the magnetic material is expressed as σ s ≥10.

3. The magnetic material according to claim 1 ,
wherein the magnetic material comprises manganese dioxide MnO 2 as a raw material.

4. A production method for a magnetic material,
wherein the magnetic material is expressed by a chemical structure formula Fe(Al 1-x Mn x ) 2 O 4 , where 0<x<1, and exhibits ferromagnetism,
the production method comprising:
preparing a mixed aqueous solution by dissolving, in distilled water, Fe nitrate, Al nitrate, and an oxide including Mn, the Fe nitrate, the Al nitrate, and the oxide being parent materials;
preparing a metal-citric acid complex by mixing citric acid and ethylene glycol with the mixed aqueous solution;
obtaining a precursor by boiling the metal-citric acid complex to a gel and drying the gel; and
obtaining the magnetic material by sintering the precursor.

5. The production method according to claim 4 ,
wherein, in the obtaining of the magnetic material, a trivalent Fe ion and a tetravalent Mn ion are reduced to a divalent Fe ion and a trivalent Mn ion, respectively.

6. The production method according to claim 4 ,
wherein the Fe nitrate is iron(III) nitrate nonahydrate Fe(NO 3 ) 3 .9H 2 O,
the Al nitrate is aluminum(III) nitrate nonahydrate Al(NO 3 ) 2 .9H 2 O, and
the oxide including Mn is manganese dioxide MnO 2 .

7. The production method according to claim 4 ,
wherein, in the preparing of the metal-citric acid complex, a molar ratio among a metal ion, the citric acid, and the ethylene glycol in the mixed aqueous solution is 1:3:9.

8. The magnetic material according to claim 2 ,
wherein the magnetic material comprises manganese dioxide MnO 2 as a raw material.

9. The production method according to claim 5 ,
wherein the Fe nitrate is iron(III) nitrate nonahydrate Fe(NO 3 ) 3 .9H 2 O,
the Al nitrate is aluminum(III) nitrate nonahydrate Al(NO 3 ) 2 .9H 2 O, and
the oxide including Mn is manganese dioxide MnO 2 .

10. The production method according to claim 5 ,
wherein, in the preparing of the metal-citric acid complex, a molar ratio among a metal ion, the citric acid, and the ethylene glycol in the mixed aqueous solution is 1:3:9.

11. The production method according to claim 6 ,
wherein, in the preparing of the metal-citric acid complex, a molar ratio among a metal ion, the citric acid, and the ethylene glycol in the mixed aqueous solution is 1:3:9.

12. The production method according to claim 9 ,
wherein, in the preparing of the metal-citric acid complex, a molar ratio among a metal ion, the citric acid, and the ethylene glycol in the mixed aqueous solution is 1:3:9.

Assignees

• Panasonic Ip Man Co Ltd
• The Doshisha

Inventors

• Hirota Ken
• Kato Masaki
• Kotani Junichi
• Matsutani Nobuya

Classifications

• C01G49/0072 Primary

  containing manganese · CPC title

• H01F1/344

  Ferrites, e.g. having a cubic spinel structure (X2+O)(Y23+O3), e.g. magnetite Fe3O4 · CPC title

• C01P2002/72

  by d-values or two theta-values, e.g. as X-ray diagram · CPC title

• C01P2004/03

  obtained by SEM · CPC title

• H01F41/0246

  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 title