对流下二元合金凝固过程的相场法研究

The study of solidification process for binary alloy with convection by phase-field simulation

采用耦合流场的相场模型,以Ni-Cu二元合金为例模拟金属非等温凝固和等温凝固时的枝晶生长,把两种模拟结果作比较。发现:两种模型得出的结果都与溶质再分配理论相符合;潜热的释放在一定程度上抑制枝晶的生长,使得非等温凝固时的平衡再分配浓度比等温凝固时低;非等温凝固的生长Peclet数与Oseen-Ivantsov理论值吻合得更好。

The phase-field model coupled with the convection field was used to simulate the dendrite growth of the alloy Ni-Cu during isothermal and non-isothermal processes,and the comparison was also made with the results.It shows that the two models are coincident with the solute redistribution theory,the latent heat released inhibites the growth of dendrite,and the concentration of solute redistribution is lower during non-isothermal process.In addition,the growth Peclet number using the non-isothermal process is in accordance with Oseen-Ivantsov solution.