  We report the results of a comparative study of the magnetic microstructure
of textured and isotropic
$\mathrm{Nd}_2\mathrm{Fe}_{14}\mathrm{B}/\alpha$-$\mathrm{Fe}$ 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 spin misalignment SANS cross
section suggests the existence of inhomogeneously magnetized regions on an
intraparticle nanometer length scale, about $40-50 \, \mathrm{nm}$ in the
remanent state. Possible origins for this spin disorder are discussed: it may
originate in thin grain-boundary layers (where the materials parameters are
different than in the $\mathrm{Nd}_2\mathrm{Fe}_{14}\mathrm{B}$ 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 $\mathrm{Nd}_2\mathrm{Fe}_{14}\mathrm{B}$ 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.
