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基于晶体生长过程中的自由能变化,提出了一个新的模型来模拟枝晶生长。在新模型中,晶体生长由固-液界面处的自由能差来驱动,采用CA方法来跟踪新的界面单元。相对于KGT模型和溶质扩散型模型,该模型更加适合于难于寻找生长速度函数及生长过程基本无成分变化的晶体如金属间化合物等的微观组织模拟。新模型具有普适性。然后,基于新模型,构建了相应的算法并予以程序实现。在一个算法循环中,以当前计算单元为中心,同时考虑了计算网格中连续三层网格单元的状态-当前生长单元、生长单元的邻居单元、以及这些邻居单元的状态。计算结果与实际情况较为一致。
Based on the change of free energy in the process of crystal growth, a new model was proposed to simulate the growth of dendrites. In the new model, the crystal growth is driven by the difference in free energy at the solid-liquid interface, using the CA method to track new interface elements. Compared with the KGT model and the solute diffusion model, the model is more suitable for the microstructure simulation of the crystal, such as intermetallic compounds, which is difficult to find the growth rate function and the basic composition-free changes of the growth process. The new model is universal. Then, based on the new model, the corresponding algorithm is constructed and implemented. In an algorithm cycle, taking the current computing unit as the center, we consider the states of the continuous three grid cells in the computing grid - the current growth unit, the neighbor units of growth units, and the states of these neighbor units. The calculation results are more consistent with the actual situation.