物理学报2012，Vol.61Issue(10)：455-462,8.
基于改进元胞自动机模型的三元合金枝晶生长的数值模拟
Simulation of dendritic growth for ternary alloys based on modified cellular automaton model
摘要
Abstract
Based on the binary cellular automaton method, a modified cellular automaton model for temary alloys is developed to simulate dendrite growth controlled by solutal effects and microsegregation in the low Peclet number regime by coupling PanEngine, which is a multicomponent thermodynamic and equilibrium calculation engine. The model can be used to calculate the interfacial equilibrium composition by considering the influence of Gibbs-Thomson effect induced curvature undercooling, and multicomponents contributed constitutional undercooling. Meanwhile, the growth velocity of interface is determined by solving the solute conservation equation simultaneously with dimensionless solute supersaturation equation for each alloying element. Moreover, equilibrium liquidus temper- ature and equilibrium solid concentration at the interface are derived by PanEngine. Free dendrite growth of A1-7%Si-χMg temary alloys is simulated by the present model, which shows that the increase of solute Mg can suppress the growths of both primary and secondary dendrite arms. Meanwhile, constrained columnar dendrite growth of A1-7%Si-0.5%Mg with the increases of pulling veloc- ity and constant thermal gradient during directional solidification is calculated. The results reveal the competitive growth of columnar dendrites, and demonstrate that the primary dendrite arm spacing would decrease as the pulling velocity increases, which accords well with the Hunt model.关键词
改进的元胞自动机/三元合金/枝晶生长Key words
modified cellular automation/ternary alloys/dendrite growth分类
矿业与冶金引用本文复制引用
石玉峰,许庆彦,柳百成..基于改进元胞自动机模型的三元合金枝晶生长的数值模拟[J].物理学报,2012,61(10):455-462,8.基金项目
国家重点基础研究发展计划（批准号：2005CB724105和2011CB706801）、国家自然科学基金（批准号：10477010和51171089）、国家高技术研究发展计划（批准号：2007AA042141）和国家科技重大专项（批准号：2009ZX04006-041-04和2011ZX04014-052）资助的课题. （）
