Abstract
In this work we investigate the evolution of the magnetic permeability and its time relaxation in different stages of nanocrystallization of four Fe73.5Cu1Nb3Si13.5B9 samples produced with different quenching rates. The results show that some typical features of the nanocrystallization process are different in alloys prepared with different quenching rates. The magnetic dis-accommodation is found to be extremely low in the nanocrystalline state. The increase in μ i upon nanocrystallization is observed to be strongly affected by the initial degree of disorder. In particular, ribbons produced with a higher quenching rate are characterized by a stronger magnetic permeability enhancement in the nanocrystalline state.