EXAFS and molecular dynamics simulation studies of Cu-Zr metallic glass: Short-to-medium range order and glass forming ability
EXAFS and molecular dynamics simulation studies of Cu-Zr metallic glass: Short-to-medium range order and glass forming ability
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Cu-Zr金属玻璃的EXAFS和分子动力学模拟研究：中短程有序度和玻璃形成能力
DOI：
10.1016/j.matchar.2018.04.036
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发表时间：
2018-07
影响因子：
4.7
通讯作者：
Li JF
中科院分区：
文献类型：
--
作者：
Lu B. F.;Kong L. T.;Li J. F.;Zhou Y. H.;Lu B. F.;Laws K. J.;Xu W. Q.;Ferry M.;Jiang Z.;Huang Y. Y.;Li JF
通过扩展 X 射线吸收精细结构 (EXAFS) 光谱和分子动力学 (MD) 模拟研究了 Cu100−xZrx(x=41.18–66.67) 金属玻璃的原子结构。结果表明，以沃罗诺伊胞为特征的典型原子团簇的分数和平均体积均具有成分依赖性。随着Zr含量的增加，以Cu和Zr为中心的配位数分别低于11和14的Voronoi团簇比例增加，而配位数较大的团簇比例减少。在主要的沃罗诺伊星团中，以铜为中心的二十面体是独特的。它们的平均体积远小于具有相同配位数的其他以铜为中心的沃罗诺伊细胞。更重要的是，它们更喜欢互连成富含五边形的二十面体超级星团。然而，与它们的邻居相比，x=44和x=50的玻璃在以Cu为中心的二十面体中没有表现出其他特殊性，除了在x=50处略微增强的互连之外，尽管玻璃形成能力（GFA）在这两种成分下达到局部最大值，这表明还有其他因素主导着GFA随成分的变化。当 x=44 和 x=50 时，松散堆积区域的自由体积显着减少，因此相应的 Cu-Zr 金属玻璃具有最大的显微硬度。
Atomic structures of Cu100−xZrx(x= 41.18–66.67) metallic glasses were investigated by extended X-ray absorption fine structure (EXAFS) spectroscopy and molecular dynamics (MD) simulations. It is demonstrated that both the fraction and average volume of the typical atomic clusters, characterized by Voronoi cells, are of compositional dependence. With the increasing of Zr content, the fraction of Cu and Zr centered Voronoi clusters with coordination number lower than 11 and 14 respectively increases, while that of clusters with larger coordination numbers reduces. Among the major Voronoi clusters, the Cu-centered icosahedra are distinctive. Their average volume is far smaller than that of the other Cu-centered Voronoi cells with the same coordination number. More importantly, they prefer to interlink into pentagon-rich icosahedral super-clusters. However, compared with their neighbors, the glasses with x = 44 and x = 50 exhibit no other particularity in Cu-centered icosahedra than a slightly enhanced interlink at x = 50 although glass forming ability (GFA) reaches a local maximum at these two compositions, indicating that there are other factors dominating the GFA change with composition. A significant reduction in free volume for the loosely packed regions takes place at x = 44 and x = 50, due to which the corresponding Cu-Zr metallic glasses have the maximum microhardness.
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影响因子：
8.6
作者：
Bin Xu;M. Falk;J. Li;L. Kong
通讯作者：
Bin Xu;M. Falk;J. Li;L. Kong
影响因子：
41.2
作者：
Ma, D.;Stoica, A. D.;Wang, X. -L.
通讯作者：
Wang, X. -L.
影响因子：
8.6
作者：
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L. Yang;G. Guo;Lianyi Chen;C. L. Huang;T. Ge;D. Chen;P. K. Liaw;Karel Saksl;Yang Ren;Qiaoshi Zeng;B. LaQua;Fugang Chen;Jianzhong Jiang
影响因子：
3.7
作者：
Li Huang;C. Wang;K. Ho
通讯作者：
Li Huang;C. Wang;K. Ho
影响因子：
3.7
作者：
D. Ma;A. Stoica;Xun-li Wang;Zhaoping Lu;M. Xu;M. Kramer
通讯作者：
D. Ma;A. Stoica;Xun-li Wang;Zhaoping Lu;M. Xu;M. Kramer