Unified approach for determining the enthalpic fictive temperature of glasses with arbitrary thermal history

We propose a unified routine to determine the enthalpic fictive temperature of a glass with arbitrary thermal history under isobaric conditions. The technique is validated both experimentally and numerically using a novel approach for modeling of glass relaxation behavior. The technique is applicable to glasses of any thermal history, as proved through a series of numerical simulations where the enthalpic fictive temperature is precisely known within the model. Also, we demonstrate that the enthalpic fictive temperature of a glass can be determined at any calorimetric scan rate in excellent agreement with modeled values.

► The graphical fictive temperature approach unifies Moynihan's and Yue's methods.
► This approach is validated experimentally and theoretically.
► The fictive temperature is independent of the upscan rate in the DSC measurement.