Effect of icosahedral clusters on β-relaxations in metallic glasses  

作　　者：X Q Gao Y T Sun Z Wang M Z Li H Y Bai 高选乔;孙奕韬;王峥;李茂枝;白海洋(Institute of Physics,Chinese Academy of Sciences;Department of Physics,Renmin University of China)

机构地区：[1]Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China [2]Department of Physics, Renmin University of China, Beijing 100872, China

出　　处：《Chinese Physics B》2017年第1期86-90,共5页中国物理B（英文版）

基　　金：supported by the National Basic Research Program of China(Grant No.2010CB731603);the National Natural Science Foundation of China(Grant Nos.50921091 and 51071170)

摘　　要：The most pronounced β-relaxation was found in the Y-based binary metallic glasses（MGs）. The correlation betweenβ-relaxation and local atomic structure was studied. The dynamic mechanical measurements were performed for three chosen binary systems： Zr-, Ti-, and Y-based MGs. The experimental results show that, in each system,the larger negative enthalpy of mixing（？Hm） between the component elements makes β-relaxation become more pronounced. The less negative value of ？Hm facilitates the formation of icosahedral clusters, which have a pinning effect on the excitation of β-relaxations and correspondingly make the β-relaxation become less pronounced. These chemical effects on β-relaxations can only be compared in the same MG system, and it is not suitable for the comparison between different systems due to the different features of the major metallic elements.The most pronounced β-relaxation was found in the Y-based binary metallic glasses（MGs）. The correlation betweenβ-relaxation and local atomic structure was studied. The dynamic mechanical measurements were performed for three chosen binary systems： Zr-, Ti-, and Y-based MGs. The experimental results show that, in each system,the larger negative enthalpy of mixing（？Hm） between the component elements makes β-relaxation become more pronounced. The less negative value of ？Hm facilitates the formation of icosahedral clusters, which have a pinning effect on the excitation of β-relaxations and correspondingly make the β-relaxation become less pronounced. These chemical effects on β-relaxations can only be compared in the same MG system, and it is not suitable for the comparison between different systems due to the different features of the major metallic elements.

关 键 词：metallic glass β-relaxation enthalpy of mixing icosahedral clusters 

分 类 号：TG139.8[一般工业技术—材料科学与工程]