公开(公告)号：US11581113B2

公开(公告)日：2023-02-14

申请号：US17543863

申请日：2021-12-07

Applicant: REGENTS OF THE UNIVERSITY OF MINNESOTA

Inventor： Jian-Ping Wang ,  YanFeng Jiang

IPC: C23C8/60 ,  H01F1/047 ,  H01F1/00 ,  H01F41/02 ,  C22C38/00 ,  C23C8/02 ,  C23C8/80 ,  C23C8/24 ,  C23C8/18 ,  C23C8/26

Abstract: A permanent magnet may include a Fe16N2 phase in a strained state. In some examples, strain may be preserved within the permanent magnet by a technique that includes etching an iron nitride-containing workpiece including Fe16N2 to introduce texture, straining the workpiece, and annealing the workpiece. In some examples, strain may be preserved within the permanent magnet by a technique that includes applying at a first temperature a layer of material to an iron nitride-containing workpiece including Fe16N2, and bringing the layer of material and the iron nitride-containing workpiece to a second temperature, where the material has a different coefficient of thermal expansion than the iron nitride-containing workpiece. A permanent magnet including an Fe16N2 phase with preserved strain also is disclosed.

公开(公告)号：US11996232B2

公开(公告)日：2024-05-28

申请号：US17245641

申请日：2021-04-30

Applicant: REGENTS OF THE UNIVERSITY OF MINNESOTA

Inventor： Jian-Ping Wang ,  YanFeng Jiang

IPC: H01F1/047 ,  B22D27/02 ,  C22C38/00 ,  H01F1/06 ,  H01F1/08 ,  H01F41/02 ,  H02K1/02

CPC classification number: H01F41/0273 ,  B22D27/02 ,  C22C38/001 ,  H01F1/047 ,  H01F1/06 ,  H01F1/08 ,  H01F41/0266 ,  H02K1/02

Abstract: Techniques are disclosed concerning applied magnetic field synthesis and processing of iron nitride magnetic materials. Some methods concern casting a material including iron in the presence of an applied magnetic field to form a workpiece including at least one iron-based phase domain including uniaxial magnetic anisotropy, wherein the applied magnetic field has a strength of at least about 0.01 Tesla (T). Also disclosed are workpieces made by such methods, apparatus for making such workpieces and bulk materials made by such methods.

公开(公告)号：US11875934B2

公开(公告)日：2024-01-16

申请号：US16423516

申请日：2019-05-28

Applicant: REGENTS OF THE UNIVERSITY OF MINNESOTA

Inventor： Jian-Ping Wang ,  Md Mehedi ,  YanFeng Jiang ,  Bin Ma ,  Delin Zhang ,  Fan Zhang ,  Jinming Liu

IPC: C01B21/06 ,  H01F1/10 ,  C22C38/00 ,  H01F41/02 ,  H01F1/03 ,  C22C38/06 ,  H01F1/00 ,  C22C38/16

CPC classification number: H01F41/0253 ,  C01B21/0622 ,  H01F1/10 ,  C21D2201/05 ,  C21D2211/008 ,  C22C38/001 ,  C22C38/06 ,  C22C38/16 ,  C22C2200/04 ,  C22C2202/02 ,  H01F1/0009 ,  H01F1/03

Abstract: The disclosure is directed to an iron-nitride material having a polycrystalline microstructure including a plurality of elongated crystallographic grains with grain boundaries, the iron-nitride material including at least one of an α″-Fe16N2 phase and a body-center-tetragonal (bct) phase comprising Fe and N. The disclosure is also directed a method producing an iron-nitride material. The method includes some combinations of preparing a raw material comprising iron, carrying out a microstructure build-up by annealing the prepared raw material at an elevated temperature and subsequently quenching the prepared raw material to produce a microstructure build-up material, annealing the microstructure build-up material, reducing the microstructure build-up material in a hydrogen environment, nitriding the reduced material to produce a nitrided material and subsequently quenching the nitrided material to a martensitic transformation temperature, stress annealing the nitrided material, and magnetic field annealing the stress-annealed material.

公开(公告)号：US11511344B2

公开(公告)日：2022-11-29

申请号：US16737156

申请日：2020-01-08

Applicant: REGENTS OF THE UNIVERSITY OF MINNESOTA

Inventor： Jian-Ping Wang ,  YanFeng Jiang

IPC: C01B21/00 ,  H01F1/08 ,  B22F9/04 ,  C22C33/02 ,  H01F1/06 ,  B22F1/054 ,  C01B21/06 ,  C23C8/26 ,  H01F41/02

Abstract: Techniques are disclosed for milling an iron-containing raw material in the presence of a nitrogen source to generate anisotropically shaped particles that include iron nitride and have an aspect ratio of at least 1.4. Techniques for nitridizing an anisotropic particle including iron, and annealing an anisotropic particle including iron nitride to form at least one α″-Fe16N2 phase domain within the anisotropic particle including iron nitride also are disclosed. In addition, techniques for aligning and joining anisotropic particles to form a bulk material including iron nitride, such as a bulk permanent magnet including at least one α″-Fe16N2 phase domain, are described. Milling apparatuses utilizing elongated bars, an electric field, and a magnetic field also are disclosed.

公开(公告)号：US11859271B2

公开(公告)日：2024-01-02

申请号：US16610285

申请日：2018-05-04

Applicant: REGENTS OF THE UNIVERSITY OF MINNESOTA

Inventor： Jian-Ping Wang ,  YanFeng Jiang ,  Md Mehedi ,  Yiming Wu ,  Bin Ma ,  Jinming Liu ,  Delin Zhang

IPC: C22C38/00 ,  C22C33/00 ,  H01F1/11 ,  H01F7/02 ,  H01F41/02

CPC classification number: C22C38/001 ,  C22C33/006 ,  H01F1/11 ,  H01F7/021 ,  H01F41/0253 ,  C22C2200/04 ,  C22C2202/02

Abstract: An example composition may include a plurality of grains including an iron nitride phase. The plurality of grains may have an average grain size between about 10 nm and about 200 nm. An example technique may include treating a composition including a plurality of grains including an iron-based phase to adjust an average grain size of the plurality of grains to between about 20 nm and about 100 nm. The example technique may include nitriding the plurality of grains to form or grow an iron nitride phase.

公开(公告)号：US11837393B2

公开(公告)日：2023-12-05

申请号：US17490800

申请日：2021-09-30

Applicant: REGENTS OF THE UNIVERSITY OF MINNESOTA

Inventor： Jian-Ping Wang ,  Bin Ma ,  Jinming Liu ,  Yiming Wu ,  YanFeng Jiang

IPC: H01F1/06 ,  C22C38/00 ,  B22F1/16 ,  B22F1/054 ,  B22F9/04 ,  C23C8/26 ,  C23C8/50 ,  C23C8/80 ,  H01F1/055 ,  H01F1/059 ,  C22C38/10 ,  B22F1/06

CPC classification number: H01F1/065 ,  B22F1/054 ,  B22F1/0553 ,  B22F1/06 ,  B22F9/04 ,  C22C38/00 ,  C22C38/001 ,  C22C38/10 ,  C23C8/26 ,  C23C8/50 ,  C23C8/80 ,  H01F1/059 ,  H01F1/0551 ,  H01F1/061 ,  B22F1/0547 ,  B22F2301/35 ,  B22F2302/20 ,  B22F2304/054 ,  H01F1/0552

Abstract: Example nanoparticles may include an iron-based core, and a shell. The shell may include a non-magnetic, anti-ferromagnetic, or ferrimagnetic material. Example alloy compositions may include an iron-based grain, and a grain boundary. The grain boundary may include a non-magnetic, anti-ferromagnetic, or ferrimagnetic material. Example techniques for forming iron-based core-shell nanoparticles may include depositing a shell on an iron-based core. The depositing may include immersing the iron-based core in a salt composition for a predetermined period of time. The depositing may include milling the iron-based core with a salt composition for a predetermined period of time. Example techniques for treating a composition comprising core-shell nanoparticles may include nitriding the composition.

公开(公告)号：US11217370B2

公开(公告)日：2022-01-04

申请号：US15546387

申请日：2016-01-22

Applicant: REGENTS OF THE UNIVERSITY OF MINNESOTA

Inventor： Jian-Ping Wang ,  YanFeng Jiang

IPC: H01F1/047 ,  H01F1/00 ,  H01F41/02 ,  C22C38/00 ,  C23C8/60 ,  C23C8/02 ,  C23C8/80 ,  C23C8/24 ,  C23C8/18 ,  C23C8/26

Abstract: A permanent magnet may include a Fe16N2 phase in a strained state. In some examples, strain may be preserved within the permanent magnet by a technique that includes etching an iron nitride-containing workpiece including Fe16N2 to introduce texture, straining the workpiece, and annealing the workpiece. In some examples, strain may be preserved within the permanent magnet by a technique that includes applying at a first temperature a layer of material to an iron nitride-containing workpiece including Fe16N2, and bringing the layer of material and the iron nitride-containing workpiece to a second temperature, where the material has a different coefficient of thermal expansion than the iron nitride-containing workpiece. A permanent magnet including an Fe16N2 phase with preserved strain also is disclosed.

公开(公告)号：US11214862B2

公开(公告)日：2022-01-04

申请号：US16446487

申请日：2019-06-19

Applicant: REGENTS OF THE UNIVERSITY OF MINNESOTA

Inventor： Jian-Ping Wang ,  YanFeng Jiang

IPC: C23C16/34 ,  C23C16/56 ,  C23C16/448 ,  C23C16/50

Abstract: The disclosure describes techniques for forming hard magnetic materials including α″-Fe16N2 using chemical vapor deposition or liquid phase epitaxy and hard materials formed according to these techniques. A method comprises heating an iron source to form a vapor comprising an iron-containing compound; depositing iron from the vapor comprising the iron-containing compound and nitrogen from a vapor comprising a nitrogen-containing compound on a substrate to form a layer comprising iron and nitrogen; and annealing the layer comprising iron and nitrogen to form at least some crystals comprising α″-Fe16N2.

公开(公告)号：US11161175B2

公开(公告)日：2021-11-02

申请号：US16340031

申请日：2017-10-06

Applicant: REGENTS OF THE UNIVERSITY OF MINNESOTA

Inventor： Jian-Ping Wang ,  Bin Ma ,  Jinming Liu ,  Yiming Wu ,  YanFeng Jiang

IPC: B22F1/02 ,  B22F1/00 ,  H01F1/055 ,  H01F1/059 ,  B22F9/04 ,  C23C8/26 ,  C23C8/50 ,  C23C8/80 ,  C22C38/00 ,  C22C38/10

Abstract: Example nanoparticles may include an iron-based core, and a shell. The shell may include a non-magnetic, anti-ferromagnetic, or ferrimagnetic material. Example alloy compositions may include an iron-based grain, and a grain boundary. The grain boundary may include a non-magnetic, anti-ferromagnetic, or ferrimagnetic material. Example techniques for forming iron-based core-shell nanoparticles may include depositing a shell on an iron-based core. The depositing may include immersing the iron-based core in a salt composition for a predetermined period of time. The depositing may include milling the iron-based core with a salt composition for a predetermined period of time. Example techniques for treating a composition comprising core-shell nanoparticles may include nitriding the composition.

公开(公告)号：US10562103B2

公开(公告)日：2020-02-18

申请号：US15546359

申请日：2016-01-22

Applicant: REGENTS OF THE UNIVERSITY OF MINNESOTA

Inventor： Jian-Ping Wang ,  YanFeng Jiang

IPC: B22F9/04 ,  B22F1/00 ,  C22C33/02 ,  H01F1/06 ,  H01F1/08 ,  C23C8/26 ,  H01F41/02

Abstract: Techniques are disclosed for milling an iron-containing raw material in the presence of a nitrogen source to generate anisotropically shaped particles that include iron nitride and have an aspect ratio of at least 1.4. Techniques for nitridizing an anisotropic particle including iron, and annealing an anisotropic particle including iron nitride to form at least one a″-Fe16N2 phase domain within the anisotropic particle including iron nitride also are disclosed. In addition, techniques for aligning and joining anisotropic particles to form a bulk material including iron nitride, such as a bulk permanent magnet including at least one a″-Fe16N2 phase domain, are described. Milling apparatuses utilizing elongated bars, an electric field, and a magnetic field also are disclosed.