Atomic structure evolutions and mechanisms of the crystallization pathway of liquid Al during rapid cooling.
Atomic structure evolutions and mechanisms of the crystallization pathway of liquid Al during rapid cooling.
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液态铝快速冷却过程中原子结构演变及结晶途径机制
DOI：
10.1039/d1ra06777j
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发表时间：
2021-12-13
期刊：
影响因子：
3.9
通讯作者：
Dong, Ke-jun
中科院分区：
文献类型：
--
作者：
Zhou, Li-li;Pan, Jia-ming;Lang, Lin;Tian, Ze-an;Mo, Yun-fei;Dong, Ke-jun
采用大尺度分子动力学模拟方法研究了纯铝的凝固过程。研究了PDF曲线第一峰和第一谷的势能、位置D、高度H和宽度W以及局部结构。发现纯Al的fcc结晶能力很强，在非晶化固体中仍存在局部晶体区域。随着温度的降低，除了Dp（第一峰的D）有反直觉的增加外，Hp单调增加；Wp、Dv、Hv单调减小；只有Wv先减小后增大。当相变发生时，它们都发生了剧烈的变化。在成核后，取向紊乱的hcp -区域作为FCC晶体的晶界或缺陷迅速转变为FCC结构，然后残存的hcp -区域规则化为少数平行层或取向紊乱的hcp -区域。如果平行层导致位错钉住，则结构演化终止；否则，它将继续。这些发现将对凝固成核理论的发展产生积极的影响。
The solidification of pure aluminum has been studied by a large-scale molecular dynamic simulation. The potential energy, position D, height H, and width W of the first peak and valley of PDF curves, and the local structures were investigated. It was found that the FCC-crystallization ability of pure Al is so strong that still local crystal regions exist in the amorphized solid. As the temperature decreases, besides the counter-intuitive increase in Dp (D of the first peak), Hp increases monotonically; Wp, Dv, and Hv decrease monotonically; only Wv first decreases and then increases. They all change critically when phase transition happens. After the nucleation, orientation-disordered HCP-regions, as the grain boundaries or defects of FCC crystals, rapidly transform into FCC structures, and then the surviving HCP-regions regularize into few parallel layers or orientation-disordered HCP-regions. If parallel layers result in dislocation pinning, structural evolution terminates; otherwise, it continues. These findings will have a positive impact on the development of the solidification and nucleation theory.
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影响因子：
4.4
作者：
Desgranges, Caroline;Delhommelle, Jerome
通讯作者：
Delhommelle, Jerome
影响因子：
3.5
作者：
Mo, Jinyong;Shen, Baolong;Liang, Xiubing
通讯作者：
Liang, Xiubing
影响因子：
4.1
作者：
PLIMPTON, S
通讯作者：
PLIMPTON, S
影响因子：
1.6
作者：
Mendelev, M. I.;Kramer, M. J.;Asta, M.
通讯作者：
Asta, M.
DOI：
10.1016/0921-5093(94)90425-1
发表时间：
1994-12-20
影响因子：
6.4
作者：
GHOSH, G
通讯作者：
GHOSH, G