Structural relaxation in Fe78Nb2B20 amorphous alloy studied by Mossbauer Spectroscopy

It was shown that soft magnetic properties of Fe78Nb2B20 amorphous alloy can be significantly improved by applying 1-h annealing at temperature 623 K (permeability increases even about 8 times). The Mössbauer Spectroscopy technique indicated that the optimized microstructure (corresponding to the maximum magnetic permeability) is free of iron nanograins and should be attributed to annealing out of free volume and a reduction of internal stresses i.e. to the relaxed amorphous phase