Generalized kinetics of overall phase transition useful for crystallization when assuming heat inertia

TL;DR

This paper develops a generalized kinetic model for phase transitions during crystallization under heat inertia, extending the KJMA equation to non-isothermal conditions with variable activation energy.

Contribution

It introduces an analogue of the KJMA equation applicable to non-isothermal crystallization with variable activation energy, enhancing modeling accuracy.

Findings

The new model accurately describes transformation degree during heating.

Reliable activation energy information can be obtained from specific experimental plots.

The model remains valid even when activation energy varies.

Abstract

Modeling of process for reaction kinetics is a fashionable subject of publications. The meaning of both the mortality and fertility terms are mathematically analyzed in details involving variation of their power exponents. We developed an analogue of the KJMA equation under non-isothermal conditions that describes the dependence of degree of transformation {\alpha}(T) at a constant rate ,q, of heating with characteristic temperature {\theta}(q) and power N. This equation is valid even when the activation energy of the process is not constant. We demonstrate that reliable information about the activation energy is obtained when the experimental data are plotted in the following coordinates: log q (heating rate) against log Tp (Peak Temperature).