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采用常温常压分子动力学模拟技术,模拟了液态Ni3Al中原子团簇在快速凝固条件下的演变过程,模型采用的是TB(tight-binding)作用势.用偶分布函数、键对和多面体等结构参数来描述快速凝固条件下团簇种类和数量的变化,并将团簇结构可视化.在2000K下,液态Ni3Al中团簇数量较少,且都是由缺陷二十面体构成;在4×1013K·S-1的冷速下,团族的数量随温度的降低不断增加,且出现完整二十面体团簇,体系最终形成了由二十面体和缺陷二十面体团簇网络所组成的非晶结构.
The evolution process of atomic clusters in liquid Ni3Al under rapid solidification conditions was modeled using the molecular dynamics simulations at normal temperature and pressure, and the TB-tight (TB) -binding potential was used in the model.Using even distribution functions, bond pairs and polyhedron structures Parameters to describe the changes of cluster species and quantity under rapid solidification conditions and to visualize the cluster structure.At 2000K, the number of clusters in the liquid Ni3Al is small and both are composed of the defect icosahedron; at 4 × 1013K · Under the cooling rate of S-1, the number of the groups increased with decreasing temperature, and the complete icosahedral clusters appeared. The system finally formed an amorphous structure composed of icosahedral and defect icosahedral clusters .