Modified Angell Plot of Viscous Flow with Application to Silicate and Metallic Glass-Forming Liquids

摘要

The behavior of the Vogel-Fulcher-Tammann (VFT), Avramov and Milchev (AM) and Mauro, Yue, Ellison, Gupta and Allan (MYEGA) functions of viscous flow in relation to t = T_g/( T- T_0) is analyzed, where T_g is glass transition temperature and T_0 is the temperature in the VFT equation at which the configurational entropy becomes zero. The T_g-scaled Arrhe-nius plot (the Angell plot) has been modified. The log η - (T_g/T) relationships in the Angell plot were modified as log η-(T_g)/(T-T_0) relationships (T_g-scaled VFT plot). The values of parameter m_1 = d(log η)/dt| T=T_g for some silicate and metallic glass-forming liquids are presented too. The parameter m_1 still exhibits "fragility" effect as does the kinetic fragility parameter m = d(log η)/d (T_g/T)| T=T_g in the Angell plot. The plot of log η_(VFE) in relation to t = T_g/(T-T_0) is the linear function unlike the Angell plot. The dependences of log η_(MYEGA) and log η_(AM) on t are not linear. It is possible to present the dependences of log η as functions of m_1 and t in the form of 3D graphs.