自适应有限元法对合金定向倾斜枝晶生长的相场法模拟

建立了合金定向倾斜枝晶生长的相场模型,采用非均匀网格的自适应有限元法求解薄界面层厚度条件下的相场模型,研究了Al-Cu(w(Cu)=4％)合金的倾斜枝晶演化过程,定量分析了冷却速率、主晶间距对凝固组织的影响.结果表明:冷却速率、主晶间距和抽拉速度可以控制倾斜枝晶的生长角度,随着冷却速率的增加,枝晶的生长会偏离择优取角向...

Phase field method study on oriented tilted dendrite growth of alloy by adaptive finite element method

The article established a phase field model that is an oriented tilted dendrite of alloy, and used a non-uniform grid adaptive finite element method to solve the phase field model of thin interface layer thickness. The thesis also researched the evolution process of the tilting dendrite of Al-Cu(w(Cu)=4%) alloy, and quantitatively analyzed the effect of cooling rate and the main crystal spacing on solidification structure. The results demonstrated that the cooling rate and the main crystal spacing and the pulling speed can control the growth angle of the tilting dendrite. With the increase of the cooling rate, the growth of dendrite will deviate from the preferred direction to the direction of temperature gradient. On the contrary, with the increase of main crystal spacing and pulling speed, the growth angle of dendrite will gradually deviate from the temperature gradient direction to the preferred crystal direction. In addition, compared with the uniform grid method, the adaptive finite element method reduces the running time of the CPU by an order of magnitude. And as the computational domain increases, the computational efficiency of the adaptive finite element method is higher.