Modeling of Convection and Macrosegregation through Appropriate Consideration of Multiphase/Multiscale Phenomena during Alloy Solidification

Abstract

Solidification processes are complex in nature, involving multiple phases and several length scales. The properties of solidified products are dictated by the microstructure, the macrostructure, and various defects present in the casting. These, in turn, are governed by the multiphase transport phenomena occurring at different length scales. In order to control and improve the quality of cast products, it is important to have a thorough understanding of various physical and physicochemical phenomena occurring at various length scales, preferably through predictive models and controlled experiments. In this context, the modeling of transport phenomena during alloy solidification has evolved over the last few decades due to the complex multiscale nature of the problem. Despite this, a model accounting for all the important length scales directly is computationally prohibitive. Thus, in the past, single-phase continuum models have often been employed with respect to a single length scale to model solidification processing. However, continuous development in understanding the physics of solidification at various length scales on one hand and the phenomenal growth of computational power on the other have allowed researchers to use increasingly complex multiphase/multiscale models in recent times. These models have allowed greater understanding of the coupled micro/macro nature of the process and have made it possible to predict solute segregation and microstructure evolution at different length scales. In this paper, a brief overview of the current status of modeling of convection and macrosegregation in alloy solidification processing is presented.

Modelling of Columnar-to-Equiaxed Transition and Inclusion Distribution in Continuously Cast Steel Billets

“…Over the past few decades, modelling of solidification phenomena has received considerable attention [1][2][3]. In particular, several researchers have focussed their attention on modelling of columnar-to-equiaxed transition (CET) during solidification, since it strongly affects the material properties [4,5].…”