Mechanical spectroscopy and X-ray diffraction measurements were employed to investigate the thermally induced structural evolution of nanocrystalline iron, prepared by mechanical attrition through tiflerent bail milling equipment in dfferent structural states. The evolution of the elastic modulus, grain size and microstrain as a finction of temperature and after selected isothermal treatments indicates that the rearrangement of structural configuration at the interfaces may stabilise the nanostructure against grain growth.