Effects of anisotropic growth on the deviations from Johnson–Mehl–Avrami kinetics

Abstract The effects of nucleation, growth and impingement on deviations from classical Johnson–Mehl–Avrami (JMA) kinetics are described. On the basis of Monte Carlo (MC) simulations of isothermal phase transformations, the deviations from the JMA kinetics due to the effects of anisotropic growth have been investigated further. An analytical approach has been adopted to describe phase transformations subjected to the effects of anisotropic growth. In combination with MC simulations, the effect of the “memory” time has been shown when the transition from JMA behavior to blocking behavior occurs during the transformation. On this basis, a physically realistic Avrami exponent has been deduced. A comparative study between the analytical description and a gamma–alpha transformation occurring in an Fe–Mn alloy under an applied load has been carried out.