Iron nitride magnetic material including coated nanoparticles

Patent metadata

Field	Value
Publication number	US-2022051835-A1
Application number	US-202117513084-A
Country	US
Kind code	A1
Filing date	Oct 28, 2021
Priority date	Mar 28, 2014
Publication date	Feb 17, 2022
Grant date	—

Abstract

The disclosure describes techniques for forming nanoparticles including Fe16N2 phase. In some examples, the nanoparticles may be formed by first forming nanoparticles including iron, nitrogen, and at least one of carbon or boron. The carbon or boron may be incorporated into the nanoparticles such that the iron, nitrogen, and at least one of carbon or boron are mixed. Alternatively, the at least one of carbon or boron may be coated on a surface of a nanoparticle including iron and nitrogen. The nanoparticle including iron, nitrogen, and at least one of carbon or boron then may be annealed to form at least one phase domain including at least one of Fe16N2, Fe16(NB)2, Fe16(NC)2, or Fe16(NCB)2.

First claim

What is claimed is:

1 . A nanoparticle comprising:
a core comprising at least one Fe 16 N 2 phase domain; and a coating comprising at least one of carbon or boron on the nanoparticle.

2 . The nanoparticle of claim 1 , wherein the coating defines a thickness between about 0.5 nanometers and about 50 nanometers, and wherein the nanoparticle comprises a diameter between about 0.5 nm and about 200 nm.

3 . The nanoparticle of claim 1 , further comprising at least one of a transition metal dopant, a rare earth metal dopant, or an oxide dopant.

4 . The nanoparticle of claim 3 , wherein the transition metal dopant is selected from Co, Mn, Cr, Ni, Ti, La, or combinations thereof.

5 . A bulk magnetic material comprising:
a plurality of consolidated nanoparticles, wherein at least one of the plurality of consolidated nanoparticles comprises: a core comprising at least one Fe 16 N 2 phase domain; and a coating comprising at least one of carbon or boron formed on the nanoparticle.

6 . The bulk magnetic material of claim 5 , wherein the coating defines a thickness between about 0.5 nanometers and about 50 nanometers, and wherein the nanoparticles comprises diameters between about 0.5 nm and about 200 nm.

7 . The bulk magnetic material of claim 5 , wherein the bulk permanent magnet material has a minimum dimension of at least 0.1 mm.

8 . The nanoparticle of claim 5 , further comprising at least one of a transition metal dopant, a rare earth metal dopant, or an oxide dopant.

9 . The nanoparticle of claim 8 , wherein the transition metal dopant is selected from Co, Mn, Cr, Ni, Ti, La, or combinations thereof.

10 . An iron nitride permanent magnet comprising:
a plurality of consolidated nanoparticles, wherein at least one of the plurality of consolidated nanoparticles comprises: a core comprising at least one Fe 16 N 2 phase domain; and a coating comprising at least one of carbon or boron formed on the nanoparticle, wherein the bulk permanent magnet material has a minimum dimension of at least 0.1 mm.

11 . The nanoparticle of claim 10 , further comprising at least one of a transition metal dopant, a rare earth metal dopant, or an oxide dopant.

12 . The nanoparticle of claim 10 , wherein the transition metal dopant is selected from Co, Mn, Cr, Ni, Ti, La, or combinations thereof.

Assignees

• Univ Minnesota
• Ut Battelle Llc
• Univ Tennessee Res Found

Inventors

• Wang Jian-Ping
• Jiang Yanfeng
• Bridges Craig A
• Brady Michael P
• Rios Orlando
• Meisner Roberta A
• Allard Jr Lawrence F
• Lara-Curzio Edgar
• He Shihai

Classifications

• B22F1/056

  Submicron particles having a size above 100 nm up to 300 nm · CPC title

• B22F1/054

  Nanosized particles · CPC title

• C23C14/586

  Nitriding · CPC title

• C23C14/185

  by cathodic sputtering · CPC title

• C23C14/3414

  Metallurgical or chemical aspects of target preparation, e.g. casting, powder metallurgy · CPC title