Nucleation of Y-Si-O Nano-clusters in Multi-microalloyed Nano-structured Ferritic Alloys:a First-principles Study  

作　　者：Shiyu He Qi Qian Zhe Huang Yuxiang Gong Jiajing Chen Yiren Wang Yong Jiang 

机构地区：[1]School of Materials Science and Engineering,Central South University,Changsha 410083,China [2]State Key Laboratory for Powder Metallurgy,Central South University,Changsha 410083,China

出　　处：《Acta Metallurgica Sinica(English Letters)》2021年第7期955-962,共8页金属学报（英文版）

基　　金：financially suppor ted by the National MCF Energy R&D Program of China(Project No.2018YFE0306100);the National Natural Science Foundation of China(No.51971249)。

摘　　要：First-principles energetics analyses were performed to investigate the nucleation of(Y-Si-O)nano-clusters(NCs)in nanostructured ferritic alloys(NFAs).It was predicted that the nucleation of(Y-Si-O)NCs follows the same general pathway as previously found for(Y-Ti/Al/Zr-O)NCs in NFAs:they all tend to begin with the(O-O)pairs and grow to(O-Y)-cores and further to larger NCs by attracting Y and other solute elements nearby.Nucleation of a hexa-atomic-[2Y-Si-3O]-cluster can reduce the total energy by 4.71 eV.Among various microalloying-induced NCs,the nucleation preference ordering was predicted as(Y-Zr-O)>(Y-Ti-O)>(Y-Al-O)>(Y-Si-O).The number densities and chemical compositions of NCs in multi-microalloyed NFAs would largely depend on the number availability of(O,Y)-cores,as well as the relative abundance and atomic diffusivities of microalloying solute elements nearby.

关 键 词：Nano-structured ferritic alloy Y-Si-O Nano-cluster FIRST-PRINCIPLES 

分 类 号：TG131[一般工业技术—材料科学与工程]