Formation and Relative Stabilities of Core-Shelled L12-Phase Nano-structures in Dilute Al–Sc–Er Alloys  

作　　者：Chaomin Zhangi Yong Jiang Xiuhua Guo Kexing Song 

机构地区：[1]School of Materials Science and Engineering,Henan University of Science and Technology,Luoyang 471023,People's Republic of China [2]School of Materials Science and Engineering,Central South University,Changsha 410083,China [3]Henan Province Key Laboratory of Nonferrous Metal Material Science and Processing Technology,Luoyang 471023,People's Republic of China [4]Collaborative Innovation Center of Nonferrous Metals,Luoyang 471023,Henan Province,China [5]Provincial and Ministerial Co-construction of Collaborative Innovation Center for Non-ferrous Metal New Materials and Advanced Processing Technology,Luoyang 471023,Henan Province,People's Republic of China

出　　处：《Acta Metallurgica Sinica(English Letters)》2020年第12期1627-1634,共8页金属学报（英文版）

基　　金：financially supported by the National Natural Science Foundation of China(No.51971249);the National MCF Energy R&D Program of China(Project No.2018YFE0306100);the Key Research and Development Projects of Shandong Province(No.2017GGX20130)。

摘　　要：First-principles thermodynamic calculations were carried out at the interface level for understanding the precipitation of coherent L12-phase nano-structures in dilute Al–Sc–Er alloys.All energetics,relevant to bulk substitution,interface formation,interfacial coherent strain and segregation,were calculated and used to evaluate the nucleation and relative stabilities of various possible L12 nano-structures.Only matrix-dissolved solute Er(or Sc)can substitute Sc(or Er)in L12-Al3Sc(or Al3Er).The inter-substitution between L12-Al3Sc and Al3Er is not energy feasible.Ternary L12-Al3(Er x Sc 1.x)precipitates tend to form the Al3Er-core and Al3Sc-shell structure with a sharp core/shell interface.Three possible formation mechanisms were proposed and examined.The eff ects of Er/Sc ratio and aging temperature on the relative stabilities of L12-phase nanostructures in Al were also discussed.

关 键 词：Al–Sc–Er alloy L12 phase CORE-SHELL Interface First-principles 

分 类 号：TG146.21[一般工业技术—材料科学与工程]