Short-range and medium-range order in supercooled liquids of alloys
Short-range and medium-range order in supercooled liquids of alloys
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DOI：
10.1016/j.msea.2006.02.380
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发表时间：
2007-03
期刊：
影响因子：
6.4
通讯作者：
M. Shimono;H. Onodera
中科院分区：
文献类型：
--
作者：
M. Shimono;H. Onodera
采用分子动力学模拟方法研究了过冷液体等温退火过程中原子团簇结构变化的弛豫行为。模拟结果表明，随着退火时间的延长，短程序二十面体有序度增加。此外，二十面体团簇的空间分布显示出几个纳米的中程秩序。这种类型的几何短程有序的二十面体对称性大大增强了合金成分具有较大的原子尺寸差异和负混合热。另一方面，各种类型的化学短程有序根据混合热的组合而增长。
Relaxation behavior of structural change at the atomic cluster level in supercooled liquids during isothermal annealing processes is investigated for a model alloy system by using molecular dynamics simulations. The simulation results show that the short-range icosahedral order grows with the annealing time. Moreover, the spatial distribution of the icosahedral clusters shows a medium-range order of a few nanometers. This type of geometrical short-range order of icosahedral symmetry is drastically enhanced by alloying components with a large atomic size difference and negative heat of mixing. On the other hand, various types of chemical short-range order grow according to a combination of heats of mixing.