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We report the results of a comparative study of the magnetic microstructure of textured and isotropic Nd 2 Fe 14 B=α-Fe nanocomposites using magnetometry, transmission electron microscopy, synchrotron x-ray diffraction, and, in particular, magnetic small-angle neutron scattering (SANS). Analysis of the magnetic neutron data of the textured specimen and computation of the correlation function of the spinmisalignment SANS cross section suggests the existence of inhomogeneously magnetized regions on an intraparticle nanometer length scale, about 40-50 nm in the remanent state. Possible origins for this spin disorder are discussed: it may originate in thin-grain-boundary layers (where the material parameters are different than in the Nd 2 Fe 14 B grains), or it may reflect the presence of crystal defects (introduced via hot pressing), or the dispersion in the orientation distribution of the magnetocrystalline anisotropy axes of the Nd 2 Fe 14 B grains. X-ray powder diffraction data reveal a crystallographic texture in the direction perpendicular to the pressing direction-a finding which might be related to the presence of a texture in the magnetization distribution, as inferred from the magnetic SANS data.

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