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)

Multiple dendritic equiaxed grain formation is common to solidification in many technical alloys in industrial solidification processes. We investigate this type of grain formation and competition during directional solidification of grain-refined Al-3.5wt.-%Ni at various solidification conditions by comparison of experimental data and 3D dendrite needle network (DNN) modeling. For the experiments in-situ x-ray radiographic characterizations in thin samples reported in literature [1] are used. DNN modeling makes use of heterogeneous nucleation, branched dendritic growth and solutal interaction between branches and multiple equiaxed grains. Here, a first comparison using a 2D modeling approach valid at low Péclet numbers [2] is extended to account for thin samples in 3D, higher Péclet-number, as well as different grain orientations. [1] N. Mangelinck-Noël, J.E. Spinelli, Ch.-A. Gandin, G. Reinhart, H. Nguyen-Thi, B. Billia, IOP Conf. Ser.: Mater. Sci. Eng. 27 (2011) 012090. [2] L. Sturz, A. Theofilatos, Acta mat. 117 (2016) 356.