# Coercivity limits in Nd-Fe-B hot-deformed magnets with ultrafine microstructure

https://mdr.nims.go.jp/datasets/c503f948-a7ef-4e21-b3ed-515e88b84a2e

## Download

- [Final_manuscript.pdf](https://mdr.nims.go.jp/filesets/4747476b-5183-4c82-9fcc-2d55b922447e/download)
- [Supplementary.pdf](https://mdr.nims.go.jp/filesets/36b92bab-0c3b-49f7-8bc1-a42813d8f4b8/download)

## Id

c503f948-a7ef-4e21-b3ed-515e88b84a2e

## Local identifier



## Visibility

open_to_public

## State

published

## Created at

2024-10-23T00:24:32.793465Z

## Updated at

2024-10-23T01:08:35.767939Z

## Published at

2026-06-30T23:29:57.968279Z

## Doi

https://doi.org/10.48505/nims.4882

## First published url

https://doi.org/10.1016/j.actamat.2024.120159

## Date published

2024-07-01

## Recorded date published

2024-9

## Resource type

journal_article

## Manuscript type

accepted_manuscript

## Collection



## Title

- title: Coercivity limits in Nd-Fe-B hot-deformed magnets with ultrafine microstructure
  title_type: original
  lang: en

## Description

- description: In this work, we developed a series of anisotropic hot-deformed Nd-Fe-B
    magnets with ultrafine grain sizes varying from 125 nm to 234 nm in the lateral
    direction. Although grain refinement is known to increase the coercivity of magnets,
    all samples exhibited identical record high coercivity of 2 T. Microstructural
    analysis showed similar intergranular phase (IGP) composition and crystallographic
    texture, but an increased number of coarse and isotropic equiaxed grains in the
    flake boundary regions of the magnets with larger grain size. Although this could
    explain significant differences in the initial magnetization curves and magnetic
    domain patterns, the experimental data alone were not enough to identify the main
    factors limiting the coercivity. To elucidate these, a micromagnetic simulation
    was performed using a realistic 1:1 scale model. We showed that grain refinement
    below 200 nm has a limited potential for coercivity enhancement of hot-deformed
    Nd-Fe-B magnets unless the exchange interaction is weakened by reducing the magnetization
    of the IGP. Negative contributions to the coercivity from texture deterioration,
    coarse grains, and magnetostatic interaction were quantified for different values
    of IGP magnetization. A clear direction on how to further improve the coercivity
    of hot-deformed magnets was provided.
  description_type: abstract
  lang: und

## Creator

- name: N. Kulesh
  role: author
  orcid: https://orcid.org/0000-0001-7046-2671
- name: A. Bolyachkin
  role: author
  orcid: https://orcid.org/0000-0003-0420-1806
- name: E. Dengina
  role: author
  orcid: https://orcid.org/0000-0001-7942-6247
- name: Xin Tang
  role: author
  orcid: https://orcid.org/0000-0001-6762-6145
- name: T. Ohkubo
  role: author
  orcid: https://orcid.org/0000-0003-3548-1951
- name: T. Kajiwara
  role: author
- name: H. Miyawaki
  role: author
- name: H. Sepehri-Amin
  role: author
  orcid: https://orcid.org/0000-0002-7856-7897
- name: K. Hono
  role: author
  orcid: https://orcid.org/0000-0001-7367-0193

## Contact agent



## Publisher

organization: Elsevier BV

## Managing organization



## Keyword

- subject: permanent magnet
  schema: not_defined
- subject: coercivity
  schema: not_defined
- subject: microstructure
  schema: not_defined
- subject: micromagnetic simulation
  schema: not_defined

## Rights

- identifier: https://creativecommons.org/licenses/by-nc-nd/4.0/

## Other identifier(s)



## Data origin

- data_origin_type: other

## Embargo

start_date: 2024-07-01
end_date: 2026-07-01

## Journal

- title: Acta Materialia
  issn: '13596454'
  volume: '276'
  article_number: '120159'

## Conference



## Related item



## Funding

- identifier: JP23H01674
  funder_name: JSPS
- identifier: JPMXP1122715503
  funder_name: 'MEXT Program: Data Creation and Utilization-Type Material Research
    and Development Project'
  description: Digital Transformation Initiative Center for Magnetic Materials

## Instrument



## Instrument operator



## Instrument managing organization



## Measurement method



## Specimen



## Chemical composition



## Structure for specimen



## Structural feature for specimen



## Specific property for specimen



## Process for specimen treatment



## Computational method



## Energy level/transition state



## Software



## Custom property



## Fileset

- id: 4747476b-5183-4c82-9fcc-2d55b922447e
  filename: Final_manuscript.pdf
  content_type: application/pdf
  size: 2032578
  md5: 2b4b66c10abfb8631243a7b40295f81b
- id: 36b92bab-0c3b-49f7-8bc1-a42813d8f4b8
  filename: Supplementary.pdf
  content_type: application/pdf
  size: 807288
  md5: a6dcd7bce9158e8de563638c54d2a449

## Thumbnail

fileset_id: 36b92bab-0c3b-49f7-8bc1-a42813d8f4b8
filename: Supplementary.pdf