Theoretical results for nucleation and growth controlled transformations indicate that a non-isothermal generalization is only possible along the lines of the isokinetic hypothesis, i.e., the invariance of the rate equation under any thermal conditions. The alternative formalism, i.e., the general use of the isothermal law and the corresponding modification of the rate equation under non-isothermal conditions, is found to be incorrect. Different methods for the evaluation of kinetic parameters are compared, taking into account even thermal lag corrections. It is illustrated by experimental results for oxide, chalcogenide and metallic glasses that all of the non-isothermal methods that yield kinetic parameters in good agreement with the appropriate isothermal results are easily derived from the usual rate equation.
ASJC Scopus subject areas
- Condensed Matter Physics
- Physical and Theoretical Chemistry