Magnetization Reversal Process in Pr-Cu Infiltrated Nd-Fe-B Nanocrystalline Magnet Investigated by Small-Angle Neutron Scattering

Magnetization reversal of a Nd-Cu-infiltrated Nd-Fe-B nanocrystalline magnet observed with small-angle neutron scattering

“…This indicates that single-particle reversal is dominant because of the magnetic isolation of Nd 2 Fe 14 B grains along the [001]-perpendicular direction due to infiltration. 12 On the other hand, the corresponding peak heights of the two q ranges for the Nd-Cu-infiltrated sample, which are similar to the as-deformed sample, indicate an incomplete magnetic isolation of the Nd 2 Fe 14 B grains along the [001]-perpendicular direction.…”

“…At À5 T, with nearly fully magnetized state in the opposite direction from the initial state, the oval shape appears to be similar with that of 5 T. This magnetic-field dependence for the SANS patterns agrees with those observed in the as-deformed and Pr-Cu-infiltrated samples. 8,11,12 SANS intensity consists of nuclear and magnetic scattering contributions, where nuclear-scattering intensity originates from the microstructure and texture of the Nd 2 Fe 14 B grains, grain boundaries, and intergranular phases, which are insensitive to the external magnetic field. Thus, we assume that magnetic-dependent SANS intensity comes from the magnetic scattering contributions, i.e., the change in spatial fluctuation of magnetic moments and development of magnetic domains.…”

“…12 In this report, we present experimental SANS results of the magnetization reversal process of Nd-Cu-infiltrated Nd-Fe-B nanocrystalline magnets and compare these results with those from as-deformed samples. The magnetic-field dependence of SANS intensity for certain q ranges shows a distinct difference between the two sample types, indicating a suppressed spatial fluctuation of magnetic moments in the Nd-Cu samples.…”

Multiple magnetic scattering in small-angle neutron scattering of Nd–Fe–B nanocrystalline magnet

“…Small-angle neutron scattering (SANS) has been recognized as a powerful experimental technique to characterize permanent magnet materials 1 2 such as Nd 2 Fe 14 B single crystal 3 , Nd-Fe-B sintered magnets 4 5 6 , hot-deformed nanocrystalline magnets 7 8 9 10 , and nanocomposites 11 12 . Because of the magnetic sensitivity and the high transparency of neutrons to matter, one can probe the magnetic properties of the materials to generate bulk averaged information.…”

“…For the development of high-performance permanent magnet materials, it is necessary to investigate magnetic structures and to reveal the origin of the coercivity. We have been reported so far SANS studies of Nd-Fe-B nanocrystalline magnets 7 8 9 10 . In previous papers, we qualitatively discussed the magnetic SANS in the magnetization reversal process.…”