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arXiv · 2109.04107

Unraveling the magnetic softness in Fe-Ni-B based nanocrystalline material by magnetic small-angle neutron scattering

Mathias Bersweiler·Michael P. Adams·Inma Peral·Joachim Kohlbrecher·Kiyonori Suzuki·Andreas Michels
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Abstract

We employ magnetic small-angle neutron scattering to investigate the magnetic interactions in $(Fe_{0.7}Ni_{0.3})_{86}B_{14}$ alloy, a HiB-NANOPERM-type soft magnetic nanocrystalline material, which exhibits an ultrafine microstructure with an average grain size below 10 nm. The neutron data reveal a significant spin-misalignment scattering, which is mainly related to the jump of the longitudinal magnetization at internal particle-matrix interfaces. The field dependence of the neutron data can be well described by the micromagnetic small-angle neutron scattering theory. In particular, the theory explains the 'clover-leaf-type' angular anisotropy observed in the purely magnetic neutron scattering cross section. The presented neutron-data analysis also provides access to the magnetic interaction parameters, such as the exchange-stiffness constant, which plays a crucial role towards the optimization of the magnetic softness of Fe-based nanocrystalline materials.

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Mathias Bersweiler, Michael P. Adams, Inma Peral, Joachim Kohlbrecher, Kiyonori Suzuki, Andreas Michels. 2022-01-19. Unraveling the magnetic softness in Fe-Ni-B based nanocrystalline material by magnetic small-angle neutron scattering. https://doi.org/10.1107/s2052252521010605

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