Onset of sidebranching in directional solidification
Onset of sidebranching in directional solidification
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DOI：
10.1103/physreve.57.3189
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发表时间：
1998-03
影响因子：
2.4
通讯作者：
M. Georgelin;A. Pocheau
中科院分区：
文献类型：
--
作者：
M. Georgelin;A. Pocheau
我们研究了不纯丁二腈定向凝固中生长细胞侧支化的发生。注意在大距离上获得均匀的单元间距，以便将该变量用作真正的控制参数。两个侧支化模式指的是不同的晶体取向观察和它们的物理等价性。侧支化的发病确定根据一个顺序参数和扫描相对于拉速，热梯度，和细胞间距。其演变与控制参数令人惊讶地揭示，在其他固定的速度和细胞间距增加热梯度增强侧支化。这些结果表明，需要改善定向凝固中的侧向分支的实验表征和理论描述。
We study the onset of sidebranching of growth cells in directional solidification of impure succinonitrile. Care is taken to obtain uniform cell spacing over large distances in order to use this variable as a true control parameter. Two sidebranching modes referring to different crystalline orientations are observed and their physical equivalence is shown. The onset of sidebranching is identified according to an order parameter and scanned with respect to pulling velocity, thermal gradient, and cell spacing. Its evolution with the control parameters surprisingly reveals that increasing thermal gradient at otherwise fixed velocity and cell spacing enhances sidebranching. These results show the need for improving the experimental characterization and the theoretical description of sidebranching in directional solidification.