An analytical expression is proposed that combines the susceptibility of liquid cast iron to solidify according to the Fe-C-X metastable system (also known as the chilling tendency of cast iron, CT). The proposed analysis incorporates the nucleation and growth processes associated with the eutectic transformation. As a result, a relationship is found between CT and factors such as the physicochemical state of liquid, the eutectic cells in flake graphite or nodule count in nodular cast iron. In particular, the CT can be related to the critical wall thickness Scr or chill width Wcr in wedge shaped castings. Finally, this work serves as a guide for an understanding of the effect of technological factors such as the melt chemistry, the spheroidizing and inoculation practice, and the holding time and temperature on the resultant CT and chill of the cast iron. Theoretical calculations of Scr and Wcr were made and then compared with experimental outcome for flake graphite and nodular cast iron. It was found that the predictions of the theoretical analysis are in rather good agreement with the experimental data.
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