Modelling of microsegregation

After a brief review of existing models of microsegregation in the dendritic arm spaces of binary alloys, a numerical microsegregation model based on conservative variables (to account for the solidification phase change) and a coordinate transformation (to account for coarsening) is outlined. In the context of this model appropriate conditions and parameters required for a comprehensive description of microsegregation are discussed and summarised. The role of submodels describing density changes and undercooling phenomena is investigated, and predictions from the model are compared with the results of recent directional solidification experiments.