Effect of thermodynamics on transformation kinetics; Analysis of recipes

For transformations occurring in the vicinity of equilibrium transformation temperature, the thermodynamic terms affect significantly the transformation kinetics and thus the results of kinetic analyzing. Accordingly, the effects of two types of thermodynamic terms (i.e., temperature- and transformed fraction-dependent terms) on the traditional kinetic recipe analyzing are evaluated. The results of the Kissinger plot and the Starink-Zahra plot are influenced by temperature-dependent thermodynamic term. The results of the Ozawa plot, the Avrami plot and the Starink-Zahra plot are affected by transformed fraction-dependent thermodynamic terms. The kinetic parameters of the hcp/bcc allotropic phase transformation in pure Zr as measured by non-isothermal differential scanning calorimetry are determined by the traditional kinetic recipe analyzing. The results further confirm the theoretical analysis.