运用基于界面追踪法的数值自洽模型研究了界面能各向异性对定向凝固枝晶生长的影响. 模拟结果表明,对于给定的凝固条件, 对应不同的一次间距P eclect数范围, 存在2个不同的界面形态解区间, 其中较小的间距P eclect数解区间对应的界面形态类似胞状晶, 较大的间距P eclect数解区间对应的界面形态类似枝状晶, 界面能各向异性的增大有利于枝晶解区间的扩大. 同时, 枝晶生长的尖端临界稳定性参数σ^*与界面能各向异性参数E₄存在幂指数关系, 并基于Fisher枝晶扩散解, 得到包含界面能各向异性参数的枝晶尖端半径表达式: R_IMS=2.5646[гD_L/Vk₀△T₀]^0.5E₄^-0.1905,△T₀=mC₀(k₀-1)/k₀; 界面能各向异性增大, 枝晶生长界面前沿过冷度减小. 枝晶生长稳态一次间距的选择主要取决于枝晶间溶质扩散场的相互作用, 而由于界面能各向异性在枝晶尖端作用的局域化, 使得界面能各向异性对定向凝固稳态一次枝晶间距影响较小.

The dendritic growth with the different solid/liquid (S/L) interface energy anisotropies in theunidirectional solidification has been investigated using the self-consistent front tracking model. It is found that,for a given solidification condition, there were two kind of interface shape solutions with the different spacing Peclect number ranges. The interface shape with the small spacing Peclect number range was similar with cellular tip, and that with the large spacing Peclect number range referred to dendritic tip.The higher S/L interface energy anisotropy was in favor of the widening of the dendritic growth solution range. There was a certain power exponential relationship between the dendritic tip marginal stability parameterσ^* and the S/L interface energy anisotropic parameter E₄. A modified Fisher dendritic tip solution, which considered the effect of S/L interface energy anisotropy, was obtained as follows: R_IMS=2.5646[гD_L/Vk₀△T₀]^0.5E₄^-0.1905,△T₀=mC₀(k₀-1)/k₀. The undercooling in front of the S/L interface decreased with increasing the anisotropic parameter. The primary dendritic spacing mainly depended on the interaction of solute diffusion field between the adjacent dendrite, and the S/L interface energy had little influence on the primary dendritic spacing due to its localized effect on the solute diffusion field near the dendritic tip.