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基于耦合流场的Wheeler模型,对界面各向异性作用下纯镍枝晶生长过程进行模拟,研究了界面动力学各向异性对枝晶形貌及尖端生长行为的影响。结果表明:在仅有界面能各向异性(ε4)时,晶粒以枝晶方式沿<100>方向生长;在仅有界面动力学各向异性(εk)时,晶粒以枝晶方式沿<110>方向生长。界面同时存在ε4、εk时,随着εk的增加,晶粒优先生长方向由<100>过渡到<110>方向,[100]和[-100]方向尖端稳态速度减小,稳态温度升高。当ε4=εk=0.04时,随着凝固时间的推移,晶粒形貌由伞状经类正方形向发达枝晶形貌转变。
Based on Wheeler model of coupled flow field, the growth of dendritic pure nickel under interface anisotropy was simulated, and the effect of interface kinetics anisotropy on dendritic morphology and tip growth behavior was studied. The results show that the grain grows dendritically along the <100> direction with only the interfacial anisotropy (ε4). In the case of the interface kinetic anisotropy (εk) only, <110> direction of growth. With the simultaneous existence of ε4 and εk, with the increase of εk, the direction of the grain preferential growth transits from <100> to the <110> direction, and the tip steady-state velocity decreases in the direction of [100] and [-100] high. When ε4 = εk = 0.04, with the solidification time, the crystal morphology changes from umbrella-like square to developed dendritic morphology.