%0 Journal Article
%T NUMERICAL SIMULATION OF CELLULAR/DENDRITE TRANSITION AND ITS GROWTH DURING DIRECTIONAL SOLIDIFICATION OF Ti44Al ALLOY<br>Numerical simulaton of cellular/dendritic transition and its growth during unidirectional solidificationin of Ti–Al alloy
%A WANGNG Kuangfei
%A LI Bangsheng
%A MI Guofa
%A GUO Jingjie
%A FU Hengzhi
%A <br>王狂飞
%A 李邦盛
%A 米国发
%A 郭景杰
%A 傅恒志
%J 金属学报
%D 2007
%I 
%X The CA method based on solute diffusion controlled model was adopted to simulate cell to dendrite transition of Ti44Al alloys at the initial stage of directional solidification with different velocities. The simulation results show that during cell/dendrite transition the mixed structure is composed of cells and dendrites, in which the secondary dendrites are absent at facing surface of some parallel closely spaced dendrites. The dendrite spacing is larger than cellular spacing at a given rate. The colmnnar grain spacing sharply increases to a maximum as solidification advanced to coexistence zone. In addition, the simulation also revealed that the increase in the number of the seeds decreased the non-uniform degree of the colmnnar grain spacing. The main influence factor affecting cell/dendrite transition is slight fluctuations of liquid composition at growth front. The simulation results also are in reasonable agreement with experiment observation at low cooling rate.
%K Ti-Al alloy
%K cell/dendrite transition
%K solute diffusion controlled model<br>Ti-Al合金
%K 胞/枝晶转变
%K 溶质扩散控制模型
%K 合金
%K 转变过程
%K 枝晶生长
%K 数值模拟
%K CELLULAR
%K SIMULATION
%K NUMERICAL
%K ALLOY
%K DIRECTIONAL
%K SOLIDIFICATION
%K DURING
%K GROWTH
%K TRANSITION
%K 模拟结果
%K 实验
%K 波动
%K 成分
%K 液界面
%K 起固
%K 程度
%K 非均匀化
%U http://www.alljournals.cn/get_abstract_url.aspx?pcid=5B3AB970F71A803DEACDC0559115BFCF0A068CD97DD29835&cid=AB188D3B70B071C57EB64E395D864ECE&jid=B061E1135F1CBDEE96CD96C109FEAD65&aid=874A1CE7C8235F7F26ABEF6CC1047069&yid=A732AF04DDA03BB3&vid=BE33CC7147FEFCA4&iid=0B39A22176CE99FB&sid=CC0ECB9C52F1B85F&eid=CEC789B3C68C3BB3&journal_id=0412-1961&journal_name=金属学报&referenced_num=5&reference_num=17