References of "Krill, C. E"
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See detailMagnetic microstructure and properties of the nanocrystalline hard magnet terbium
Weissmüller, J.; Michels, D.; Michels, Andreas UL et al

in Physica Status Solidi A. Applied Research (2002), 189

We present an experimental study of the magnetic properties and magnetic microstructure in the nanocrystalline hard magnet Tb. Field-dependent small-angle neutron scattering (SANS) data suggest that up to ... [more ▼]

We present an experimental study of the magnetic properties and magnetic microstructure in the nanocrystalline hard magnet Tb. Field-dependent small-angle neutron scattering (SANS) data suggest that up to applied fields of several Tesla the magnetization remains locked in to the basal planes of the hcp crystal lattice of each individual crystallite; as a consequence, domain-wall movement along the basal planes is eliminated as a mechanism for magnetization reversal, and the coercive field is substantially increased. [less ▲]

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See detailMagnetic small-angle neutron scattering by nanocrystalline terbium
Weissmüller, J.; Michels, D.; Michels, Andreas UL et al

in Scripta Materialia (2001), 44(8), 2357-2361

We present an experimental study of the magnetic microstructure in the nanocrystalline hard magnet Tb. Field-dependent SANS data are analyzed quantitatively in terms of the correlation function of the ... [more ▼]

We present an experimental study of the magnetic microstructure in the nanocrystalline hard magnet Tb. Field-dependent SANS data are analyzed quantitatively in terms of the correlation function of the spin misalignment. We find that up to applied fields of several Tesla the magnetization remains ‘locked in’ to the basal planes of the hcp crystal lattice of each individual crystallite; But that the in-plane orientation of the spins is highly nonuniform within each particle. This internal structure can be suppressed by the applied field. [less ▲]

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See detailModelling the influence of grain-size-dependent solute drag on the kinetics of grain growth in nanocrystalline materials
Michels, Andreas UL; Krill, C. E.; Ehrhardt, H. et al

in Acta Materialia (1999), 47(7), 2143-2152

The large relative change in total grain-boundary area that accompanies grain growth in a nanocrystalline material has a potentially strong influence on the kinetics of grain growth whenever grain ... [more ▼]

The large relative change in total grain-boundary area that accompanies grain growth in a nanocrystalline material has a potentially strong influence on the kinetics of grain growth whenever grain-boundary migration is controlled by solute (impurity) drag. As the grain-boundary area decreases, the concentration of solute or impurity atoms segregated to the boundaries is expected to increase rapidly, introducing a grain-size dependence to the retarding force on boundary migration. We have modified the Burke equation—which assumes the drag force to be independent of the average grain size—to take into account a linear dependence of grain-boundary pinning on grain size. The form of the resulting grain-growth curve is surprisingly similar to Burke's solution; in fact, a constant rescaling of the boundary mobility parameter is sufficient to map one solution approximately onto the other. The activation energies for grain-boundary motion calculated from the temperature dependence of the mobility parameter are therefore identical for both models. This fact provides an explanation for the success of Burke's solution in fitting grain-growth data obtained in systems, such as nanocrystalline materials, for which the assumption of grain-size-independent solute drag is incorrect. [less ▲]

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See detailGrain-growth kinetics in nanocrystalline iron prepared by ball milling
Michels, Andreas UL; Krill, C. E.; Natter, H. et al

in Grain Growth in Polycrystalline Materials III (1998)

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