公开(公告)号：US20180025841A1

公开(公告)日：2018-01-25

申请号：US15546407

申请日：2015-07-22

Applicant: REGENTS OF THE UNIVERSITY OF MINNESOTA

Inventor： Jian-Ping WANG ,  YanFeng JIANG

IPC: H01F41/02 ,  H02K1/02 ,  H01F1/06 ,  H01F1/047

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 ironbased 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：US20240112855A1

公开(公告)日：2024-04-04

申请号：US18529331

申请日：2023-12-05

Applicant: REGENTS OF THE UNIVERSITY OF MINNESOTA

Inventor： Jian-Ping WANG ,  Md MEHEDI ,  YanFeng JIANG ,  Bin MA ,  Delin ZHANG ,  Fan ZHANG ,  Jinming LIU

IPC: H01F41/02 ,  C01B21/06 ,  H01F1/10

CPC classification number: H01F41/0253 ,  C01B21/0622 ,  H01F1/10 ,  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：US20210180174A1

公开(公告)日：2021-06-17

申请号：US17182857

申请日：2021-02-23

Applicant: Regents of the University of Minnesota ,  UT-BATTELLE, LLC

Inventor： Michael P. BRADY ,  Orlando RIOS ,  YanFeng JIANG ,  Gerard M. LUDTKA ,  Craig A. BRIDGES ,  Jian-Ping WANG ,  Xiaowei ZHANG ,  Lawrence F. ALLARD ,  Edgar LARA-CURZIO

IPC: C23C8/26 ,  C21D1/26 ,  C21D6/00 ,  C22C38/00 ,  C23C28/00 ,  C01B21/06 ,  C22C33/00 ,  H01F1/06

Abstract: A method may include annealing a material including iron and nitrogen in the presence of an applied magnetic field to form at least one Fe16N2 phase domain. The applied magnetic field may have a strength of at least about 0.2 Tesla (T).

公开(公告)号：US20200038951A1

公开(公告)日：2020-02-06

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 ,  H01F1/059 ,  H01F1/055 ,  B22F1/00 ,  B22F9/04 ,  C23C8/50 ,  C23C8/26 ,  C23C8/80

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：US20190316253A1

公开(公告)日：2019-10-17

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 ,  C23C16/448 ,  C23C16/50 ,  C23C16/56

Abstract: The disclosure describes hard magnetic materials including α″-Fe16N2 and techniques for forming hard magnetic materials including α″-Fe16N2 using chemical vapor deposition or liquid phase epitaxy.

公开(公告)号：US20170365381A1

公开(公告)日：2017-12-21

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 ,  H01F41/02 ,  H01F1/00

CPC classification number: H01F1/047 ,  C22C38/001 ,  C23C8/02 ,  C23C8/18 ,  C23C8/24 ,  C23C8/26 ,  C23C8/60 ,  C23C8/80 ,  H01F1/0063 ,  H01F41/0253

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.