Mathematical modeling of microstructural development in hypoeutectic cast iron

A mathematical heat-transfer/microstructural model has been developed to pr edict the evolution of proeutectic austenite, white iron eutectic, and gray iron eutectic during solidification of hypoeutectic cast iron, based on th e commercial finite-element code ABAQUS. Specialized routines which employ relationships describing nucleation and growth of equiaxed primary austenit e, gray iron eutectic, and white iron eutectic have been formulated and inc orporated into ABAQUS through user-specified subroutines. The relationships used in the model to describe microstructural evolution have been adapted from relationships describing equiaxed growth in the literature. The model has been validated/fine tuned against temperature data collected from a Qui K-Cup sample, which contained a thermocouple embedded approximately in the center of the casting. The phase distribution predicted with the model has been compared to the measured phase distribution inferred from the variatio n in hardness within the QuiK-Cup sample and from image analysis of photomi crographs of the polished and etched microstructure, Overall, the model res ults were found to agree well with the measured distribution of the microst ructure.