Superalloys are a class of alloys aiming at high temperature applications. Single crystal turbine blades are manufactured through directional solidification and subsequent heat treatment, in a highly sophisticated process. Detailed knowledge of microstructural evolution is a key issue. A phase-field based method for the simulation of microstructural evolution in a spatial resolved manner is presented. The simulations are done using a unit cell model to represent transverse sections through directionally growing dendrites. Within the unit cell the micros tincture formation is simulated with the phase-field code MICRESS~R. The constitution of phases and diffusion of the alloying elements is taken into account via coupling to thermodynamic calculations. The as-cast microstructures obtained from the solidification simulations define the starting conditions for the homogenization simulations. The simulations were supplemented by experiments. Samples of a 5 component superalloy were directionally solidified under various conditions. Metallographic sections were analysed in terms of primary spacing, microsegregation, phase formation and the solidification interval. Selected samples were exposed to solution heat treatment for different durations and temperatures. Good agreement between the simulations and experimental results is found.
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