Non-isothermal crystallization kinetics of Fe₇₁Nb₆B₂₃ amorphous ribbons

The Fe₇₁Nb₆B₂₃ amorphous ribbons were prepared using melt spinning method. Differential scanning calorimeter was applied to investigate non-isothermal crystallization kinetics of the amorphous ribbons at different heating rates from 10 to 40 K/min. As the heating rate is increased, the values of T_g, T_x, and T_p are shifted toward a higher temperature region, suggesting that the amorphous ribbons have obvious crystallization kinetics. The effective activation energies including E_g, E_x and E_p were calculated with Kissinger and Ozawa equations by means of DSC traces at different step-up temperature rates. Thermodynamical mechanism of the amorphous ribbons was explained. The results reveal that the nucleation is quite more difficult than growth of the grains because E_x is larger than E_p. And the crystallization kinetics is more obvious than that of glass transition.