Low-temperature β-relaxation promotes crystallization in oxide glasses

Abstract

Primary (α) structural relaxation is known to influence the nucleation behavior in glasses and it has recently been proposed to account for the so-called classical nucleation theory “breakdown” in oxide glasses around the glass transition temperature. However, it is unclear whether secondary (β-) relaxation, predominant at lower temperatures, also plays a role in promoting crystallization. Here, we study the correlation between crystallization kinetics and β-relaxation of three types of oxide glasses with distinct chemical bonds by subjecting the glasses to low-temperature annealing. We find that the activation energy of crystallization (Ea) exhibits an exponential decay with increasing annealing duration for all studied glasses. Such a decrease in Ea is found to be associated with the structural rearrangements in the glasses, especially showing a negative correlation with the enhanced atomistic interplays around modifying cations. Our findings thus point to a universal linkage between β-relaxation and nucleation kinetics in oxide network glasses.