5th International Conference on Advances in Solidification Processes (ICASP-5) 5th International Symposium on Cutting Edge of Computer Simulation of Solidification, Casting and Refining (CSSCR-5)

The quantitative prediction of dendrite fragmentation has remained a major issue in the modeling of solidification processes. A systematic approach to this issue is presented that consists of two parts. First, a thorough analysis is carried out of existing and new experimental data. A suite of different image processing techniques is developed that allows for obtaining robust statistics of the complex history of dendrite fragments, ranging from the growth conditions of sidearms through their detachment to the buoyant motion as free dendrites. Second, an analytical model is proposed that incorporates local solidification conditions of the sidebranches as well as the dynamics of the pinch-off process, which has been characterized in a previous numerical study. The predictive potential of this model is discussed in the context of the columnar-to-equiaxed transition and formation of single-crystal defects.