Microstructure development in Kolmogorov, Johnson-Mehl, and Avrami nucleation and growth kinetics

A statistical model with the ability to evaluate the microstructure develop ed in nucleation and growth kinetics is built in the framework of the Kolmo gorov, Johnson-Mehl, and Avrami theory. A populational approach is used to compute the observed grain-size distribution. The impingement process which delays grain growth is analyzed, and the effective growth rate of each pop ulation is estimated considering the previous grain history. The proposed m odel is integrated for a wide range of nucleation and growth protocols, inc luding constant nucleation, pre-existing nuclei, and intermittent nucleatio n with interface or diffusion-controlled grain growth. The results are comp ared with Monte Carlo simulations, giving quantitative agreement even in ca ses where previous models fail. [S0163-1829(99)01629-X].