X.L. Tian C.W. Zhan J.X. Hou X.C. Chen J.J. Sun
材料科学技术(英文)
A nanocrystal model for liquid metals and amorphous metals has been developed. With the nanocrystal model, the broadening peak profiles (BPPs) of Cu, Al, Al65Cu20Fe15 alloy, Cu70Ni30 alloy and Fe50Si50 alloy were gained by broadening the X-ray diffraction (XRD) peaks of a crystal lattice. By comparing the BPPs with the XRD intensity curves measured on the liquid metals, it is found that the BPPs are closely in agreement with the XRD intensity curves, respectively, except the Fe50Si50 alloy. Therefore, the nanocrystal model can be used to determine if the atomic cluster structure of the liquid metal is similar to the structure of its crystal lattice.
关键词:
Liquid metal
,
Atomic Cluster
,
Structure
,
Crystal Lattice
Rangsu LIU
,
Jiyong LI
,
K.J.Dong
,
R.P.Zou
,
A.B.Yu
材料科学技术(英文)
A molecular dynamics simulation of rapid cooling process has been performed for a large-scale system consisting of 400,000 Al atoms with a supercomputer. To study the formation and evolution mechanisms of nano-clusters in solidification, the so-called cluster-type index method has been applied to describe the structural configurations of the basic small clusters and combined larger clusters obtained from the simulation. The results show that relatively large nano-clusters are formed from small and medium sized clusters through continuous mutual competitions of annexation and evolution of small clusters in a seesaw manner, giving a structure different from the multi-shell structure where an atom acts as the center of a cluster and the surrounding atoms are arranged according to a certain rule.
关键词:
Liquid metal
,
null
,
null