Nanocrystalline Fe-Zr-Si(Cu) boron-free alloys

► Formation of nanocrystalline Fe-Zr-Si(Cu) alloys by annealing amorphous precursors. ► Identification of crystalline phases by Mössbauer spectroscopy and X-ray diffraction. ► Primary crystallized solid solution Fe(SiZr) transformed to bcc-Fe(Si) upon elevated annealing temperature. ► Coercive fields increase significantly with the increase of annealing temperature.