Solid phase transformation in ductile iron - A benchmark for computational simulation of microstructure

To predict room temperature microstructure of ductile ir on through computer modeling, it is necessary to obtain a quantitative description of both the eutectic and eutectoid transformations. In this study, a series of quenching experiments were carried out, with the purpose of determining the temporal evolution of microstructural parameters during the eutectoid transformation. A quantitative description of microstructural evolution and of its thermal history was obtained. These data are extremely useful for macro-transport/transformation kinetics modeling of ductile iron. It was apparent that, in order to model the eutectoid transformation, the influence of graphite nodule count must be taken into account for ferritic ductile iron, while the effect of the number of austenite grains should be included for pearlitic ductile iron. The negative segregation characteristics for silicon and copper, and the positive segregation characteristics for chromium and manganese have been verified, and partition coefficients were quantified.