Crystallization of glassy Fe40Ni40P14B6 alloy on heating and the melt amorphization during melt-spinning processing

Abstract

Crystallization of amorphous Fe40Ni40P14B6 melt-spun ribbons has been studied and analyzed using the classical theory equations. It was established that crystallization of this glass occurs by non-steady state homogeneous nucleation and interface controlled crystal growth. All parameters controlling the rates of crystal nucleation and growth including the temperature dependence of the transient time were estimated from comparison of the calculated kinetic curves with those experimentally measured. By substitution of these parameters and experimentally determined values of the heat transfer coefficient into the numerical approach describing crystallization in a melt-spinning technique amorphization of the Fe40Ni40P14B6 melt has been analyzed. The dominant role of the heterogeneous nucleating in this melt crystallization under rapid cooling in the majority of experiments has been confirmed and the most probable values of the heterogeneous sites density and wetting angle have been estimated by comparing of the experimental and calculated ‘temperature-time’ cooling curves.