Evaluation of crystallization kinetics of glasses by non-isothermal analysis

Based on Johnson-Mehl-Avrami transition equation, this paper proposes a new non-isothermal method for evaluating the crystallization kinetics of glasses. An equation relating the kinetic parameters of the crystallization activation energy, E, and the frequency factor, v, to the inflection-point temperature, T-f, and the heating rate, beta, of differential thermal analysis (DTA) experiment is established. The inflection-point temperature, T-f, can be easily determined from the derivative differential thermal analysis (DDTA) curves. The validity of the proposed method is ascertained by applying it to Li2O . 2SiO(2) glass. The acquired values of the crystallization kinetic parameters by this method are excellent agreement with the isothermal analysis results. In contrast, the traditional non-isothermal methods give much higher values. (C) 2001 Kluwer Academic Publishers.