Correlation between Barkhausen Noise and Coercivity in Amorphous and Nanocrystalline Fe-Cu-Nb-Si-B Alloys

Samples of amorphous and nanocrystalline alloys were prepared by proper annealing of the metallic glasses: Fe$\text{}_{73.5}$Cu$\text{}_{1}$Nb$\text{}_{3}$Si$\text{}_{13.5}$B$\text{}_{9}$ and Fe$\text{}_{73.5}$Cu$\text{}_{1}$Nb$\text{}_{3}$Si $\text{}_{17.5}$B$\text{}_{5}$. Magnetic hardening of the alloys at the onset of crystallization was studied by the two independent techniques, i.e. measurements of the magnetization hysteresis loops and Barkhausen effect. A good correlation between the coercivity and the maximum power of the Barkhausen noise has been found in these two compositions of the alloys.