来流对Al-Cu合金三维树枝晶生长的影响

• 作 者: 张显飞 赵九洲
• 机 构: 中国科学院金属研究所,沈阳理工大学材料科学与工程学院,
• 出 处: 金属学报
• 发表日期: 2012年05期
• 关键词: Al-Cu合金 三维树枝晶生长 来流 元胞自动机

建立了模拟二元合金树枝晶生长的三维元胞自动机模型,以Al-4%Cu(质量分数)为模型合金,模拟了合金过冷熔体中树枝晶的生长过程,研究了来流对枝晶生长的影响.结果表明,来流对合金过冷熔体中三维树枝晶生长影响显著,迎流侧枝晶尖端生长速度随来流速度的增大而增大,枝晶尖端半径随来流速度的增大而减小;随着来流速度的增大,枝晶尖端选择参数减小;在给定过冷度条件下,随界面能各向异性的增大,来流对枝晶尖端选择参数的影响增强;对于给定的合金(或界面能各向异性),来流对枝晶尖端选择参数的影响随着过冷度的增大而增强.

A three-dimensional cellular automata model was established to simulate the growth of dendrite in binary alloy. The growth process of dendrite was simulated with Al-4% Cu (mass fraction) as model alloy. The results show that the flow has a significant effect on the dendrite growth of the three-dimensional dendrite in the undercooled melt, and the growth rate of the dendrite tip increases with the increase of the velocity of flow, With the increase of the velocity of flow, the selection parameter of dendritic tip decreases; under the condition of given degree of supercooling, with the increase of interfacial energy anisotropy, the flow of dendrite tip The effect of the choice of parameters is enhanced; for a given alloy (or interfacial anisotropy), the effect of incoming flow on the dendrite tip selection parameters increases with increasing undercooling.