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
• 来源期刊: 金属学报（英文版）
• 年，卷（期）: 2021,（7）
• 页码范围: 955-962
• 页数: 8页
• 语种: 英文

摘要

First-principles energetics analyses were performed to investigate the nucleation of (Y-Si-O) nano-clusters (NCs) in nano-structured 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.