Influence of defect thickness on the angular dependence of coercivity in rare-earth permanent magnets

Bance, S, et al. (2014), Influence of defect thickness on the angular dependence of coercivity in rare-earth permanent magnets, Appl. Phys. Lett., 104(18), 182408, doi:10.1063/1.4876451.

Abstract

The coercive field and angular dependence of the coercive field of single-grain Nd2Fe14B permanent magnets are computed using finite element micromagnetics. It is shown that the thickness of surface defects plays a critical role in determining the reversal process. For small defect thicknesses reversal is heavily driven by nucleation, whereas with increasing defect thickness domain wall de-pinning becomes more important. This change results in an observable shift between two well-known behavioral models. A similar trend is observed in experimental measurements of bulk samples, where an Nd-Cu infiltration process has been used to enhance coercivity by modifying the grain boundaries. When account is taken of the imperfect grain alignment of real magnets, the single-grain computed results appears to closely match experimental behaviour.

Further information

• http://dx.doi.org/10.1063/1.4876451

BibTeX

@article{id1994,
  author = {S Bance and H Oezelt and T Schrefl and G Ciuta and N M  Dempsey and D Givord and M Winklhofer and G Hrkac and G Zimanyi and O Gutfleisch and T G Woodcock and T Shoji and M Yano and A Kato and A Manabe},
  journal = {Appl. Phys. Lett.},
  month = {may},
  number = {18},
  pages = {182408},
  title = {{Influence of defect thickness on the angular dependence of coercivity in rare-earth permanent magnets}},
  volume = {104},
  year = {2014},
  url = {http://dx.doi.org/10.1063/1.4876451},
  doi = {10.1063/1.4876451},
}

EndNote

%0 Journal Article
%A Bance, S
%A Oezelt, H
%A Schrefl, T
%A Ciuta, G
%A Dempsey, N M 
%A Givord, D
%A Winklhofer, M
%A Hrkac, G
%A Zimanyi, G
%A Gutfleisch, O
%A Woodcock, T G
%A Shoji, T
%A Yano, M
%A Kato, A
%A Manabe, A
%D 2014
%N 18
%V 104
%J Appl. Phys. Lett.
%P 182408
%T Influence of defect thickness on the angular dependence of coercivity in rare-earth permanent magnets
%U http://dx.doi.org/10.1063/1.4876451
%8 may