Vogel–Fulcher–Tammann plot for viscosity scaled with temperature interval between actual and ideal glass transitions for metallic glasses in liquid and supercooled liquid states

Abstract

The glass transition temperature- ( T g-) scaled Arrhenius plot (Angell plot) has been modified by considering viscosity ( η) of metallic glasses in a liquid and supercooled liquid state with absolute temperature ( T). The log η−( T g/ T) relationships in Angell plot were modified as log η−[( T g− T 0)/( T− T 0)] relationships where T 0 is the ideal glass transition temperature from Vogel–Fulcher–Tammann (VFT) parameters. Introducing Δ T g−0 (≡ T g− T 0) makes it possible to regard the modified plot as Δ T g−0-scaled VFT plot. Using B from VFT parameters provides a relationship D* VFT = B/Δ T g−0 ∼38, in which T g was principally measured at a heating rate of 0.333 K s −1. The analyses revealed that Δ T g−0-scaled VFT plot reflects α relaxation due to a motion of groups of atoms, and that Δ T g−0/( T l− T 0) where T l is the liquidus temperature can be a glass-forming parameter.