Structural Features of the Extraordinary Low Glass Transition Temperature for Au65Cu18Si17 Bulk Metallic Glass
Structural Features of the Extraordinary Low Glass Transition Temperature for Au65Cu18Si17 Bulk Metallic Glass
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Au65Cu18Si17块体金属玻璃极低玻璃化转变温度的结构特征
DOI：
10.2320/matertrans.mf201307
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发表时间：
2013
影响因子：
1.2
通讯作者：
J. Mizuno
中科院分区：
文献类型：
--
作者：
M. Matsuura;Wei Zhang;S. Yamaura;T. Fujita;K. Ohara;S. Kohara;J. Mizuno
Au65Cu18Si17大块金属玻璃(BMG)具有极低的玻璃化转变温度(<；100℃)和较宽的过冷液相区。为了阐明Au65Cu18Si17 BMG的超低玻璃化转变温度和高玻璃形成能力的结构特征，用同步辐射进行了高能X射线衍射和扩展X射线吸收精细结构测量。结构因子S(Q)的第一个尖峰和高波数q的振荡可以归因于Au-Au关联的主导权重因子。用反蒙特卡罗(RMC)方法同时对HEXRD和EXAFS数据进行了模拟。得到的RMC模型显示出高度致密的堆积结构，在Au原子周围有大量的二十面体类型的团簇，而在Si原子周围有少量的二十面体类型的团簇。偏铜对分布函数Gcu，Cu(R)在较短的原子间距处出现一个尖峰，即2.38i。较短的原子间距和较大的热涨落是Au65Cu18Si17 BMG玻璃化转变温度较低的结构特征之一。
Au65Cu18Si17 bulk metallic glass (BMG) exhibits an extraordinary low glass transition temperature (<100°C) and a wide supercooled liquid region. In order to elucidate the structural features of the extraordinary low glass transition temperature and high glass forming ability of the Au65Cu18Si17 BMG, high-energy X-ray diffraction (HEXRD) and Extended X-ray Absorption Fine Structure (EXAFS) measurements were carried out using synchrotron radiation. A sharp first peak and oscillation of the structure factor S(Q) up to the high wave number Q can be attributed to the dominant weighting factor of the AuAu correlation over others. A reverse Monte Carlo (RMC) simulation was applied simultaneously to the HEXRD and EXAFS data. The obtained RMC model shows a quite highly dense packed structure with large amount of icosahedral type clusters around Au atoms while small ones around Si atoms. The partial CuCu pair distribution function gCu,Cu(r) shows a sharp peak at a short interatomic distance, i.e., 2.38 i. The CuCu pairs with short interatomic distances and the large thermal fluctuation around Cu atoms are considered to be one of the structural characteristics of the low glass transition temperature of the Au65Cu18Si17 BMG.
影响因子：
3.7
作者：
Chirawatkul, Prae;Zeidler, Anita;Fischer, Henry E.
通讯作者：
Fischer, Henry E.