On the Formation of Macrosegregations in Steel Ingot Castings

A multiphase approach is used to study macrosegregation phenomena that occur during solidification of steel ingot castings. The goal is to enhance the understanding of different mechanisms of macrosegregation formation. 4 different cases are presented consecutively with increasing complexity of the model assumptions and increasing dimensions: (1) feeding-induced macrosegregations in 1-dimentional unidirectional solidification situation, (2) macrosegregations caused by thermosolutal buoyancy driven flow in a 2-dimensional axially symmetric benchmark ingot, (3) macrosegregations caused by grain sedimentation in the same 2-dimensional ingot, and (4) macrosegregations which form during mixed equiaxed-columnar solidification in a full 3-dimensional benchmark ingot.