Kinetic Monte Carlo simulations of the sintering microstructural evolution in density graded stainless steel fabricated by SPS

Abstract

The microstructural evolution and sintering behavior of density graded stainless steel 304 L were evaluated using three-dimensional kinetic Potts Monte Carlo simulations. Density graded samples were fabricated using spark plasma sintering (SPS) and were axially divided into five regions in the thermal gradient direction to quantify the density variations using images obtained through scanning electron microscopy (SEM). Finite element analysis was then utilized to quantify the temperature gradient within the samples. Subsequently, two different kinetic Monte Carlo (kMC) simulations were applied to evaluate the microstructural evolution in the samples. The simulation results were compared with the density values obtained from the SEM images and the overall density measurements of the samples. Microstructural evolution parameters, such as densification and sintering stress profiles, were then obtained, followed by the evaluation of the effects of several parameters on the density profiles of the SPS-sintered samples. The results show that kMC simulations accurately evaluate the microstructural evolution of sintering, quantify the sintering behavior, and predict the effects of several parameters on the density profiles. kMC simulations of density graded material sintering provide predictive results to control the resulting sintered microstructure and to identify the sintering stage of each region of the density graded samples.