Domain-wall pinning at inhomogenities of arbitrary cross-sectional geometry

Ralph Skomski, Jian Zhou, Arti Kashyap, David J. Sellmyer

Research output: Contribution to journalArticle

10 Citations (Scopus)

Abstract

The coercivity of cellular Sm-Co based permanent magnets is investigated by model calculations. The grain boundaries responsible for the pinning coercivity are modeled as planar inhomogenities with arbitrary cross-sectional geometry. The calculation yields a physically transparent integral equation for the pinning energy, whose derivative is the pinning force. The theory rationalizes experimental data on a semiquantitative level, but without adjustable parameters, and bridges the gap between smooth concentration gradients and abrupt interfaces. Explicit results are obtained for sinoidal profiles, for very thin grain boundaries, and for profiles intermediate between attractive and repulsive pinning. The corrections predicted by the present model elucidate the occurrence of coercivity when the main and grain-boundary phases have the same wall energy.

Original languageEnglish (US)
Pages (from-to)2946-2948
Number of pages3
JournalIEEE Transactions on Magnetics
Volume40
Issue number4 II
DOIs
StatePublished - Jul 1 2004

Fingerprint

Domain walls
Coercive force
domain wall
Grain boundaries
coercivity
Geometry
grain boundaries
geometry
Permanent magnets
Integral equations
profiles
permanent magnets
Derivatives
integral equations
occurrences
gradients
energy

Keywords

  • Coercive force
  • Magnetic anisotropy
  • Magnetic films
  • Permanent magnets
  • Samarium alloys

ASJC Scopus subject areas

  • Electronic, Optical and Magnetic Materials
  • Electrical and Electronic Engineering

Cite this

Domain-wall pinning at inhomogenities of arbitrary cross-sectional geometry. / Skomski, Ralph; Zhou, Jian; Kashyap, Arti; Sellmyer, David J.

In: IEEE Transactions on Magnetics, Vol. 40, No. 4 II, 01.07.2004, p. 2946-2948.

Research output: Contribution to journalArticle

Skomski, Ralph ; Zhou, Jian ; Kashyap, Arti ; Sellmyer, David J. / Domain-wall pinning at inhomogenities of arbitrary cross-sectional geometry. In: IEEE Transactions on Magnetics. 2004 ; Vol. 40, No. 4 II. pp. 2946-2948.
@article{1d2a7ea5aa3548688531eecb5718e16c,
title = "Domain-wall pinning at inhomogenities of arbitrary cross-sectional geometry",
abstract = "The coercivity of cellular Sm-Co based permanent magnets is investigated by model calculations. The grain boundaries responsible for the pinning coercivity are modeled as planar inhomogenities with arbitrary cross-sectional geometry. The calculation yields a physically transparent integral equation for the pinning energy, whose derivative is the pinning force. The theory rationalizes experimental data on a semiquantitative level, but without adjustable parameters, and bridges the gap between smooth concentration gradients and abrupt interfaces. Explicit results are obtained for sinoidal profiles, for very thin grain boundaries, and for profiles intermediate between attractive and repulsive pinning. The corrections predicted by the present model elucidate the occurrence of coercivity when the main and grain-boundary phases have the same wall energy.",
keywords = "Coercive force, Magnetic anisotropy, Magnetic films, Permanent magnets, Samarium alloys",
author = "Ralph Skomski and Jian Zhou and Arti Kashyap and Sellmyer, {David J.}",
year = "2004",
month = "7",
day = "1",
doi = "10.1109/TMAG.2004.832163",
language = "English (US)",
volume = "40",
pages = "2946--2948",
journal = "IEEE Transactions on Magnetics",
issn = "0018-9464",
publisher = "Institute of Electrical and Electronics Engineers Inc.",
number = "4 II",

}

TY - JOUR

T1 - Domain-wall pinning at inhomogenities of arbitrary cross-sectional geometry

AU - Skomski, Ralph

AU - Zhou, Jian

AU - Kashyap, Arti

AU - Sellmyer, David J.

PY - 2004/7/1

Y1 - 2004/7/1

N2 - The coercivity of cellular Sm-Co based permanent magnets is investigated by model calculations. The grain boundaries responsible for the pinning coercivity are modeled as planar inhomogenities with arbitrary cross-sectional geometry. The calculation yields a physically transparent integral equation for the pinning energy, whose derivative is the pinning force. The theory rationalizes experimental data on a semiquantitative level, but without adjustable parameters, and bridges the gap between smooth concentration gradients and abrupt interfaces. Explicit results are obtained for sinoidal profiles, for very thin grain boundaries, and for profiles intermediate between attractive and repulsive pinning. The corrections predicted by the present model elucidate the occurrence of coercivity when the main and grain-boundary phases have the same wall energy.

AB - The coercivity of cellular Sm-Co based permanent magnets is investigated by model calculations. The grain boundaries responsible for the pinning coercivity are modeled as planar inhomogenities with arbitrary cross-sectional geometry. The calculation yields a physically transparent integral equation for the pinning energy, whose derivative is the pinning force. The theory rationalizes experimental data on a semiquantitative level, but without adjustable parameters, and bridges the gap between smooth concentration gradients and abrupt interfaces. Explicit results are obtained for sinoidal profiles, for very thin grain boundaries, and for profiles intermediate between attractive and repulsive pinning. The corrections predicted by the present model elucidate the occurrence of coercivity when the main and grain-boundary phases have the same wall energy.

KW - Coercive force

KW - Magnetic anisotropy

KW - Magnetic films

KW - Permanent magnets

KW - Samarium alloys

UR - http://www.scopus.com/inward/record.url?scp=4444261829&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=4444261829&partnerID=8YFLogxK

U2 - 10.1109/TMAG.2004.832163

DO - 10.1109/TMAG.2004.832163

M3 - Article

AN - SCOPUS:4444261829

VL - 40

SP - 2946

EP - 2948

JO - IEEE Transactions on Magnetics

JF - IEEE Transactions on Magnetics

SN - 0018-9464

IS - 4 II

ER -