On the possible generalization of JMAK-type kinetic functions

11th Hungarian Conference on Materials Science

Réti, T.^1 ; Deus, A.M.^2 ; Felde, I.^1 ; Réger, M.^1

Óbuda University, Budapest, Hungary^1

University of Lisbon, Lisbon, Portugal^2

关键词: Autonomous differential equation;    Decomposition process;    Fitting parameters;    Johnson-mehl-avrami-kolmogorov;    Kinetic equations;    Kinetic functions;    Multiphase model;    Solid-state diffusion;   

Others  :  https://iopscience.iop.org/article/10.1088/1757-899X/426/1/012039/pdf
DOI  :  10.1088/1757-899X/426/1/012039

来源: IOP

【 摘 要 】

The Johnson-Mehl-Avrami-Kolmogorov (JMAK) kinetic equation is generally used for describing the progress of solid state diffusion-controlled transformations. The traditional JMAK model is applicable for modeling only monophase decomposition (precipitation) processes. This paper deals with possible generalizations of the classical JMAK kinetic model by taking into consideration the simultaneous occurrence of more parallel transformations. It is revealed that the Jones-Bhadeshia kinetic model belonging to the family of the strongly coupled multiphase models has only a limited practical application because it contains only few fitting parameters. Moreover, it has been shown and demonstrated that for predicting decomposition processes it is more advantageous to use a multiphase kinetic model including a finite set of ordinary autonomous differential equations.