论文部分内容阅读
利用耦合溶质场的相场模型模拟计算了Ni-Cu二元合金单晶粒和多晶粒枝晶生长过程。计算结果表明:枝晶生长初期,在枝晶相互接触碰撞前,晶粒间无相互影响,与单晶粒生长过程相同;在枝晶相互接触碰撞的区域和计算区域边界出现溶质的富集,造成了实际过冷度的减小从而抑制了枝晶的生长速度,致使枝晶的生长受到了抑制,出现了枝晶弯曲、尖端变秃等现象;在枝晶没有相互接触区域因实际过冷度不同出现了择优现象,多晶粒生长过程不能简单地看成是多个独立单晶粒在空间上的叠加。将计算模拟结果和实验结果进行了比较,两者吻合良好。
The phase-field model of coupled solute field was used to simulate the growth of single-crystal and multi-crystal dendrites in Ni-Cu binary alloys. The results show that there is no interaction between the dendrites before the dendrite contacts with each other in the initial stage of dendrite growth, which is the same as that of the single grain growth. In the dendrite intercluster and solute zone, Resulting in the reduction of the actual undercooled and thus dendrite growth rate, resulting in dendrite growth has been suppressed, there dendrite bending, tip bald phenomenon; no dendrite mutual contact area due to the actual subcooling The degree of preference shows the phenomenon of merit. The growth of multi-grains can not simply be regarded as the superposition of multiple independent single grains in space. The simulation results are compared with the experimental results, and the two are in good agreement.