Analysis of conditions of crystallization suppression in Fe40Ni40P14B6 melt

The critical cooling rates required for suppression of Fe40Ni40P14B6 melt crystallization were estimated in the framework of the formalism of classical theory of crystallization assuming homogeneous nucleation rate, linear isotropic growth and Kolmogorov-Johnson-Mehl-Arami kinetics. Both the calculated “time-temperature-transformation” diagrams and the integral form of the Kolmogov’s equation for the case of continuous cooling were used for the estimations. The temperature dependences of the rates of crystal nucleation and growth were calculated with using of the values of the thermodynamic and kinetic parameters governing the crystal formation in amorphous phase as well as with the three-parameter temperature dependence of diffusivity proposed in the study. The critical cooling rates for different combinations of the equations describing nucleation and growth of crystals were estimated and the conditions for the correct prediction of the glass forming ability of Fe40Ni40P14B6 melt were established.