Merging of the α and β relaxations and aging via the Johari–Goldstein modes in rapidly quenched metallic glasses

Abstract

This paper provides evidence that the physical aging of deeply and rapidly quenched metallic glasses is promoted by the Johari–Goldstein slow β relaxation, resulting in a significant irreversible increase in the mechanical modulus on initial heating. Dynamic mechanical analysis has been used to characterize relaxation phenomena of a strong and a fragile metallic glass. In addition, we can extrapolate the temperature dependence of β- and α-relaxation peaks to higher temperatures and calculate the merging temperature for both types of glasses.