Phase field method simulation of faceted dendrite growth with arbitrary symmetries
(1. Department of Applied Physics, School of Science, Northwestern Polytechnical University, Xi’an 710129, China;
2. School of Software and Microelectronics, Northwestern Polytechnical University, Xi’an 710129, China;
3. Department of Applied Physics, School of Science, Xi’an University of Science and Technology, Xi’an 710054, China)
Abstract: A numerical simulation based on a regularized phase field model is developed to describe faceted dendrite growth morphology. The effects of mesh grid, anisotropy, supersaturation and fold symmetry on dendrite growth morphology were investigated, respectively. These results indicate that the nucleus grows into a hexagonal symmetry faceted dendrite. When the mesh grid is above 640×640, the size has no much effect on the shape. With the increase in the anisotropy value, the tip velocities of faceted dendrite increase and reach a balance value, and then decrease gradually. With the increase in the supersaturation value, crystal evolves from circle to the developed faceted dendrite morphology. Based on the Wulff theory and faceted symmetry morphology diagram, the proposed model was proved to be effective, and it can be generalized to arbitrary crystal symmetries.
Key words: phase field method; strong anisotropy; faceted dendrite; Wulff theory; tip velocity; symmetry