Analysis of the nanocrystalline phase formation process in amorphous Fe-X-Si-B alloys

Abstract

The process of nanocrystalline phase formation, affecting magnetic properties, in amorphous Fe78Si8 Bι4, Fe76 ΑI2 Si8 Β14 , Fe76 Cr2 Si8 B14 and Fe76 Mo2 Si8 B14 alloys has been studied in the paper. Investigations have been carried out using the electrical resistivity method, magnetic methods, transmission electron microscopy and X-ray diffraction. A nanocrystalline phase in the amorphous matrix has been obtained by isochronous or isothermal vacuum annealing. Phase composition of samples has been determined directly after manufacturing and after crystallization annealing on the basis of X-ray diffraction and electron diffraction. Transmission electron microscopy was used to determine phase morphology, dimensions of formed nanocrystalline phase and transition phase. Alloying elements have been found to affect changes of magnetic properties in amorphous and nanocrystalline states. For Fe76Mo2 Si8 Β14 alloys a significant increase in crystallization temperature, making difficult nanocrystalline phase growth and increase in thermal stability of magnetic permeability have been observed.