Dependence of Dendritic Side-branches on Parameters in Phase-Field Simulations

Abstract

The influence of phase-field parameters on dendritic side-branches is studied by using a phase-field model coupled with thermal noise. The result of calculation indicates that, the thermal diffusion layer collected around the dendrite tends to become thinner with the undercooling increasing, which is favorable to the growth of the side-branches and the dendrite takes on the morphology of developed side-branches; The less coupling coefficient is, the quicker the dendrite tip velocity converges on the Green function calculation, the more developed the side-branches are; The anisotropy coefficient " influences the steady state of the dendrite tip, the largeris, the greater the dendrite tip velocity is, the more developed the side-branches are and the smaller the DAS is; The magnitude of thermal noise F u has an obvious effect upon temperature field, when appropriate value is assigned to F u , the noise can promote the emergence of side-branches, but it does not influence the tip operating state.

Phase-field modeling of the microstructure evolution and heterogeneous nucleation in solidifying ternary Al–Cu–Ni alloys

“…An interface noise is added to the evolution equations for the phase fields represented by Langevin forces in accordance to the results of fluctuation theory described in Refs. [19][20][21] to simulate the heterogeneous nucleation on the macroscale.…”