Per: GUILHERME DIAS DA FONSECA (Universidade federal fluminense ), André Luiz Moraes Alves (UNIVERSIDADE FEDERAL FLUMINENSE ), Felipe da Silva Siqueira (UNIVERSIDADE FEDERAL FLUMINENSE ), Camila dos Santos Pinto (UNIVERSIDADE FEDERAL FLUMINENSE ), Weslley Luiz da Silva Assis (UNIVERSIDADE FEDERAL FLUMINENSE ), Paulo Rangel Rios (UNIVERSIDADE FEDERAL FLUMINENSE )
Abstract:
In this work, the kinetic behavior of phase transformations by nucleation and growth in the polyhedra interfaces (faces, edges and vertices), of Kelvin, Voronoi and Monte Carlo matrices was studied through computacional simulation. With the main objective to compare results of the simulations with the analytical models of theory of Johnson Mehl-Avrami-Kolmogorov (JMAK) and John W.Cahn, the matrices were generated by stochastic models and through the Casual Cone growth method. The understanding of engineering about the behavior of phase transformations by nucleation and growth are important to predict posible nucleations sites, as well as to understand the behavior of the constituents present in iron carbono diagram, decomposition of austenite, recrystallization process, among others. Thus, the computational modeling was used to study the phase transformations by nucleation and growth, getting results of volumetric fraction, the microstructural path and the contiguity. Both results were important for microstructural characterization and to describe the distribution of nuclei in space. Was observed from the results obtained, that if the nuclei are well distributed in the interfaces the impinge-me will be weak, leading to Voronoi and Kelvin simulations to corroborate with teh analytical modelo JMAK. On the other hand, the Monte Carlo model did not present the same behavior. It was evidenced that randomness will not be valid in all cases. It was also verified that the amount of nuclei increases significantly, the distribution loses the characteristic of randomness and starts behaving like clusters, corroborating with the analytical modelo of Cahn
