  High-pressure torsion (HPT), a technique of severe plastic deformation (SPD),
is shown as a promising processing method for exchange-spring magnetic
materials in bulk form. Powder mixtures of Fe and SmCo$_{5}$ are consolidated
and deformed by HPT exhibiting sample dimensions of several millimetres, being
essential for bulky magnetic applications. The structural evolution during HPT
deformation of Fe-SmCo$_{5}$ compounds at room- and elevated- temperatures of
chemical compositions consisting of 87, 47, 24 and 10 wt.% Fe is studied and
microstructurally analysed. Electron microscopy and synchrotron X-ray
diffraction reveal a dual-phase nanostructured composite for the as-deformed
samples with grain refinement after HPT deformation. SQUID magnetometry
measurements show hysteresis curves of an exchange coupled nanocomposite at
room temperature, while for low temperatures a decoupling of Fe and SmCo$_{5}$
is observed. Furthermore, exchange interactions between the hard- and
soft-magnetic phase can explain a shift of the hysteresis curve. Strong
emphasis is devoted to the correlation between the magnetic properties and the
evolving nano-structure during HPT deformation, which is conducted for a 1:1
composition ratio of Fe to SmCo$_{5}$. SQUID magnetometry measurements show an
increasing saturation magnetisation for increasing strain $\gamma$ and a
maximum of the coercive field strength at a shear strain of $\gamma$ = 75.
