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 λ is, the quicker the dendrite tip velocity converges on the Green function calculation, the more developed the side-branches are; The anisotropy coefficient ε influences the steady state of the dendrite tip, the largeris, the greater the dendrite tip velocity is, the more developed the side-branches arc and the smaller the DAS is; The magnitude of thermal noise Fu has an obvious effect upon temperature field, when appropriate value is assigned to Fu, the noise can promote the emergence of side-branches, but it does not influence the tip operating state. ©2005 The Japan Institute of Metals.