Phase-field simulation of tip splitting in dendritic growth of Fe-C alloy
Phase-field simulation of tip splitting in dendritic growth of Fe-C alloy
复制标题
Fe-C合金枝晶生长过程中尖端分裂的相场模拟
DOI：
10.1016/s1006-706x(17)30024-9
复制
发表时间：
2017-02-01
影响因子：
2.5
通讯作者：
Chen, Li-wen
中科院分区：
文献类型：
--
作者：
Kang, Yong-sheng;Jin, Yu-chun;Chen, Li-wen
Two types of dendrite tip splitting including dendrite orientation transition and twinned-like dendrites in Fe-C alloys were investigated by phase-field method. In equiaxed growth, the possible dendrite growth directions and the effect of supersaturation on tip splitting were discussed; the dendrite orientation transition was observed, and it was found that the orientation regions of anisotropy parameters were reduced from three to two with increasing the supersaturation, which was due to the effect of interfacial anisotropy controlled by the solute in front of S/L interface changing with the increase of supersaturation. In directional solidification, it was found that the twinned-like dendrites were formed with the fixed anisotropy couples and no seaweed dendrites were observed; these were concluded from the results of competition between process anisotropy and inherent anisotropy. The formation process of twinned-like dendrite was investigated by tip splitting phenomenon, which was related to the changes of dendrite tips growth velocity. Then, the critical speed of tips splitting and solute concentration of twinned-like dendrites were investigated, and a new type of microsegregation in Fe-C alloys was proposed to supplement the dendrite growth theories.
