Solidification modelling

The modelling of solidification of a metal/alloy in a mold cavity is increasingly becoming popular with numerous attempts being made to understand the phenomena that occur at the level of the casting (macro level) and those that occur at the microscopic level (micro level). An attempt has been made to describe the phenomena occurring at both the macro and the micro levels. At the macro level, the effect of fluid flow on various thermal and solidification parameters has been studied. The results were compared with simulations carried out considering conduction alone and with experimental results. The relative importance of including fluid flow on solidification simulation of a casting has been brought out. At the micro level, an algorithm based on the macro-micro model to take the melt superheat into account while numerically predicting the grain size and dendritic arm spacing at different locations of an Al-7%Si alloy sand casting has been developed. The results are compared with the experimental values.