摘要
应用同步辐射X射线衍射(XRD)和广延X射线吸收精细结构边方法(EXAFS),结合反蒙特卡罗(RMC)拟合、Voronoi分形技术等对Zr50Cu50二元和Zr48Cu45Al7三元金属玻璃材料的微观结构进行了系统的研究.结果表明:ZrCuAl三元金属玻璃中Al原子与Zr原子、Cu原子之间存在强相互作用,表现为键长的明显缩短,导致其微观结构中的Voronoi团簇体积普遍小于Zr50Cu50,即前者的团簇内部原子更加密堆.这种原子密堆团簇可望从微观结构上解释CuZr体系掺Al后非晶形成能力大大提高的原因.
Atomic structures of Zr48Cu45Al7 ternary and Zr50Cu50 binary metallic glasses were investigated by performing reverse Monte Carlo （RMC） simulation upon synchrotron radiation based X-ray diffraction （XRD） and extended X-ray absorption fine structure （EXAFS） data. Bond shortening in Zr-Al and Cu-Al atomic pairs was detected in Zr48 Cu45 Al7,which is attributed to strong interactions between Al atoms and its neighbors. Subsequently,their atomic structure was further analyzed by Voronoi tessellation method,it was found that all kinds of Voronoi clusters have smaller volume in Zr48Cu45Al7 than their counterparts in Zr50Cu50. Accordingly it is suggested that atoms may be more densely packed in atomic structure of Zr48Cu45Al7 ternary than in corresponding Zr50Cu50 binary MG at cluster scale,which may be the structural origin of high glass-forming ability of CuZr-based bulk metallic glass prepared by Al addition.
出处
《物理学报》
SCIE
EI
CAS
CSCD
北大核心
2011年第1期443-448,共6页
Acta Physica Sinica
基金
国家自然科学基金(批准号:10805027)
江苏省自然科学基金(批准号:BK2008397)
浙江省自然科学基金(批准号:Y4090167)
南京航空航天大学基本科研业务费专项科研项目(批准号:NS2010168)资助的课题~~
关键词
大块金属玻璃
原子结构
玻璃形成能力
同步辐射技术
bulk metallic glass（BMG）
atomic structure
glass-forming ability（GFA）
synchrotron radiation techniques
