摘要
用元胞自动机(Cellular Automaton,CA)模型研究了界面能各向异性对二维定向凝固胞晶的生长形态的影响,建立了判定胞晶生长达到稳态的判据.结果显示,当界面能各向异性强度非常小时,胞晶尖端很容易分岔,胞晶形态不容易稳定.而当界面能各向异性强度足够大时,容易形成稳定的胞晶形态,同时界面能各向异性强度会显著影响稳定胞晶的形态,界面能各向异性越强,稳态胞晶间距越小,胞晶尖端半径越小,尖端半径与胞晶间距的比值越小,固液界面前沿的浓度与过冷度越小.
The growth patterns of cellulars in directional solidification are investigated numerically using the cellular automata （CA） model in two dimensions. A criterion which determine whether the cellulars reach stable state is derived from the analysis of simulated results. The simulated results also show that it is easy for tip splitting to appear for cellulars when the surface tention anisotropy is very small. So it is hard to obtain stable cellular arrays. However, if the amplitude of surface tention anisotropy is strong enough, it is easy to obtain stable cellular arrays. And the intensity of surface energy anisotropy can considerably influence the stable cellular patterns. The stronger the surface energy anisotropy, the smaller the stable cellular spacing and the cellular tip radius are, and the smaller the ratio between tip radius and cellular spacing, the smaller the tip concentration and the tip undercooling are.
出处
《物理学报》
SCIE
EI
CAS
CSCD
北大核心
2012年第22期484-491,共8页
Acta Physica Sinica
基金
国家自然科学基金(批准号:50971102
50901061)
国家重点基础研究发展计划(973)(批准号:2011CB610402)
高等学校学科创新引智计划(批准号:08040)
西北工业大学凝固技术国家重点实验室基金(批准号:02-TZ-2008)资助的课题~~
关键词
元胞自动机
胞晶
各向异性
cellular automata, cellular growth, anisotropy.
