Kinetics of crystallization of Zr52Cu18Ni14Al10Ti6 metallic glass

Metallic glasses have received considerable attention in comparison to normal metallic materials due to their superior physical and mechanical properties. These systems possess large under cooled region, a dagger T (a dagger T = T (x) - T (g) where, T (x) is crystallization temperature and T (g) is glass transition temperature) and hence increased thermal stability against crystallization. Due to this, the study of their crystallization kinetics is important and interesting. It is interesting because of the fact that, crystallization becomes multi-step process due to several components present in these systems. In this paper, we report the experimental investigations of crystallization of Zr52Cu18Ni14Al10Ti6 glassy alloy system, which is among the best non-beryllium containing glasses, using differential scanning calorimetry (DSC). The crystallization, as expected, consists of multiple steps. Interestingly, the peak heights of these steps vary with heating rate. At lower heating rates, first peak is most prominent and subsequently diminishes with increase in heating rate with last peak prominence visible at highest heating rate. Both, iso-kinetic and iso-conversional methods of analysis of kinetics of crystallization have been used to evaluate the activation energy and Avrami exponents and consistent results are obtained.