Modeling of Nd-Oxide Grain Boundary Phases in Nd-Fe-B Sintered Magnets

G. Hrkac, K. Butler, T.G. Woodcock, L. Saharan, T. Schrefl, O. Gutfleisch

Research output: Contribution to journalArticle

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Abstract

We use atomistic and micromagnetic simulations combined with atomic-scale, aberration-corrected transmission electron microscopy to study the anisotropy profile of the interface between a Nd2O3-hP5 and a Nd2Fe14B phase. It is shown that a hybrid Morse-Buckingham potential approach can be used to study mixed-metallic and oxide-rich systems and to calculate surface-energy-induced large strains and potentially large relaxation effects on the adjacent grains. These are used to derive a magnetoelastic anisotropy energy from a first-order perturbation of the magnetoelastic Hamiltonian and are used to evaluate its effect on coercivity. It is shown that the change in coercivity originates from these distortions in the Nd2Fe14B crystal lattice close to the grain boundary, and the coercivity can be evaluated using such a multiscale modeling approach.

Original languageEnglish
Pages (from-to)1138-1143
JournalJOM
Volume66
Issue number7
DOIs
Publication statusPublished - Jul 2014

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Coercive force
Oxides
Magnets
Grain boundaries
Anisotropy
Morse potential
Hamiltonians
Aberrations
Interfacial energy
Crystal lattices
Transmission electron microscopy

Cite this

Hrkac, G., Butler, K., Woodcock, T. G., Saharan, L., Schrefl, T., & Gutfleisch, O. (2014). Modeling of Nd-Oxide Grain Boundary Phases in Nd-Fe-B Sintered Magnets. JOM, 66(7), 1138-1143. https://doi.org/10.1007/s11837-014-0980-5

Modeling of Nd-Oxide Grain Boundary Phases in Nd-Fe-B Sintered Magnets. / Hrkac, G.; Butler, K.; Woodcock, T.G.; Saharan, L.; Schrefl, T.; Gutfleisch, O.

In: JOM, Vol. 66, No. 7, 07.2014, p. 1138-1143.

Research output: Contribution to journalArticle

Hrkac, G, Butler, K, Woodcock, TG, Saharan, L, Schrefl, T & Gutfleisch, O 2014, 'Modeling of Nd-Oxide Grain Boundary Phases in Nd-Fe-B Sintered Magnets', JOM, vol. 66, no. 7, pp. 1138-1143. https://doi.org/10.1007/s11837-014-0980-5
Hrkac G, Butler K, Woodcock TG, Saharan L, Schrefl T, Gutfleisch O. Modeling of Nd-Oxide Grain Boundary Phases in Nd-Fe-B Sintered Magnets. JOM. 2014 Jul;66(7):1138-1143. https://doi.org/10.1007/s11837-014-0980-5
Hrkac, G. ; Butler, K. ; Woodcock, T.G. ; Saharan, L. ; Schrefl, T. ; Gutfleisch, O. / Modeling of Nd-Oxide Grain Boundary Phases in Nd-Fe-B Sintered Magnets. In: JOM. 2014 ; Vol. 66, No. 7. pp. 1138-1143.
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