| The steady state shapes of solid-liquid interface under various conditions, during directional solidification of pure materials between two straight walls, were calculated by numerical analysis. The transition from the interface shapes governed by the interface energy to that governed by the mobility can occur as the pulling rate changes. At a high pulling rate where the interface shapes are governed by the mobility anisotropy, there is a critical mobility anisotropy above which the faceted interface appears. At a high pulling velocity and with a high mobility anisotropy, the faceted interface shapes depend on the wetting angle, ψ between the interface and the wall only at the range of π/4$lt;ψ$lt;5π/4. At the other range of wetting angle the macroscopic interface shape is independent of the wetting angle. The faceted interface can be composed of the planes with high crystallographic indices if the mobility anisotropy, at the high pulling velocity, is slightly larger than the critical value or if the wetting angle, at the high pulling velocity and with the high mobility anisotropy, is at a range of π/4$lt;ψ$lt;π2. |
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