Microstructure of 18R-type long period ordered structure phase in Mg_(97)Y_2Zn_1 alloy  

Mg_(97)Y_2Zn_1合金中18R型长周期有序相的微观结构(英文)

作　　者：唐平英[1] 吴萌萌[1] 唐壁玉[1,2] 王继伟[2] 彭立明[3] 丁文江[3] 

机构地区：[1]广西大学化学化工学院,南宁530004 [2]湘潭大学材料与光电物理学院,湘潭411105 [3]上海交通大学材料科学与工程学院轻合金精密成型国家工程研究中心,上海200030

出　　处：《Transactions of Nonferrous Metals Society of China》2011年第4期801-806,共6页中国有色金属学报（英文版）

基　　金：Projects(50861002,51071053)supported by the National Natural Science Foundation of China;Project(0991051)supported by NaturalScience Foundation of Guangxi Province,China;Project(KF0803)supported by Open Project of Key Laboratory of Materials Design and Preparation Technology of Hunan Province,China;Project(X071117)supported by Scientific Research Foundation of Guangxi University,China

摘　　要：The microstructure of the 18R-type long period stacking ordered （LPSO） phase in Mg 97 Y 2 Zn 1 alloy was investigated by the first principles calculation. The arrangement rule of Zn and Y atoms in the LPSO structure is determined theoretically. The calculation results reveal that the additive atoms are firstly located in the fault layers at the two ends of the 18R-type LPSO structure, and then extend to fault layers in the interior, which is in good agreement with the experimental observations. This feature also implies the microstructural relationship between 18R and other LPSO structures. The cohesive energy and the formation heat indicate the dependence of the stability of 18R LPSO structure on contents of Y and Zn atoms. The calculated electronic structures reveal the underlying mechanism of microstructure and the stability of 18R LPSO structure.通过第一性原理计算研究Mg97Y2Zn1合金中18R型长周期有序相(LPSO)的微观结构,从理论上确定Zn和Y原子在LPSO相中的排列。结果表明:添加原子首先分布在18R型LPSO相两端的层错层,然后向内部的层错层延伸。计算结果与实验现象非常吻合。同时,也揭示了18R与其他LPSO相之间的微观结构关系;结合能和形成焓表明了18R型LPSO相的稳定性与Y和Zn原子含量之间的关系。计算得到的电子结构揭示了18R型LPSO相微观结构和稳定性潜在的机理。

关 键 词：Mg 97 Y 2 Zn 1 alloy 18R LPSO structure the first principles MICROSTRUCTURE electronic structure 

分 类 号：TG146.22[一般工业技术—材料科学与工程]