Simulations of the initial transient during directional solidification of multicomponent alloys using the phase field method

This paper presents simulations of directional solidification of multicomponent alloys using the phase field method. In order to calculate thermodynamic quantities of the alloy, the phase field model has been coupled to multicomponent thermodynamic databases in an `online' mode using the TQ-Interface of the software Thermo-Calc. Simulations of directional solidification of several alloys from the Ni-Al-Cr-Co-Ti system are presented for different pulling speeds. The results predict oscillations of the solidification velocity and the element concentrations evolving in the course of the initial transient as has been analytically shown for binary systems. In multicomponent systems these oscillations not only depend on the pulling speed but also on alloy composition.