NUMERICAL SIMULATION ON SOLIDIFICATION MICROSTRUCTURE OF CAST STEEL USING CELLULAR AUTOMATON METHOD

摘要

The microstructure evolution of ASTM A216 WCA cast steel during solidification and consequent cooling process was simulated using a cellular automaton (CA) model. In the simulation, the growth velocities of δ/L and γ /L interfaces were calculated based on the relationship between solid fraction and temperature predicted using Scheil model, and the growth velocities of γ /δ and α/γ interfaces were calculated using a mixed-mode model for multicomponent systems. The peritectic solidification, α phase precipitation, and eutectoid transformation were simulated, and the grain size and area fraction of a phase as well as the mean interlamellar spacing of pearlite were obtained. To validate the model, a sand mold step-shaped casting was produced and metallographic examination was carried out. It was shown that the simulated results are in good agreement with the experimental results.