Static measurements of α- and β-relaxations in Zr-based bulk metallic glasses

The high- and low-temperature relaxations in Zr-based bulk metallic glasses (BMGs) were investigated in terms of volume relaxation. Both relaxations exhibited the decrease of volume during the relaxation, and their behaviors were well described with a stretched exponential relaxation function. The kinetics of high-temperature relaxation was represented by a Vogel-Fulcher-Tammann equation for the relaxation time and by Kohlrausch indices linearly increased with temperature. On the other hand, the kinetics of low-temperature relaxation for respective Zr₅₅Cu₃₀Ni5Al₁₀ BMG was characterized by an Arrhenius type temperature dependence of the relaxation time, and by almost constant value of Kohlrausch index. Consequently, the high- and low-temperature relaxations were regarded as α-relaxation and slow β-relaxation reported for dynamical measurements of the structural relaxation, respectively.