Predicting microstructures from phase transformation kinetics: the case of isochronal heating and cooling from a supersaturated matrix

Microstructures resulting from nucleation and growth phase transformations occurring under various time–temperature programs were simulated and analysed. The transformation kinetics was described by a modular kinetic model and information from this model was used to provide 'global' rules for application in a geometric algorithm to simulate the microstructure. The microstructures for heating and cooling transformations, in particular as revealed by the grain-size distributions (GSDs), differ distinctly as a consequence of the different temperature dependences of the nucleation and growth rates. The differences in grain-size distributions on the basis of volume-weighted, area-weighted and line-intercept grain sizes were discussed in the light of their sensitivity for revealing the kinetics of the underlying phase transformation