Comparison of transformations with inhomogeneous nucleation and transformations with inhomogeneous growth velocity

Abstract

In this paper, we carry out computer simulations of transformations to compare two distinct situations regarding nucleation and growth. The first situation is that in which the nucleation is not homogeneous in space: the nuclei are located inhomogeneously within the matrix, but the growth velocity is the same everywhere. The second situation is that the nuclei are located homogeneously within the matrix, but the growth velocity is inhomogeneous. Microstructure and transformation kinetics of the two transformations are compared. The main result is that the transformation kinetics is affected by either inhomogeneous nucleation or inhomogeneous growth. Nonetheless, an inhomogeneity in nucleation appears to have a stronger effect on the microstructural inhomogeneity than an inhomogeneity in velocity. Keywords: Computer simulation, Microstructure, Phase transformations, Nucleation and growth transformations, Analytical methods