J. Mater. Sci. Technol. ›› 2023, Vol. 148: 41-51.DOI: 10.1016/j.jmst.2022.10.083

• Research article • Previous Articles     Next Articles

Effects of Sc on the vacancy and solute behaviours in aluminium

Xingpu Zhanga,b,1, Liangliang Xuc,1, Wenxin Hud, Haofei Zhoue, Jiangwei Wanga,b,*   

  1. aCenter of Electron Microscopy and State Key Laboratory of Silicon Materials, School of Materials Science and Engineering, Zhejiang University, Hangzhou 310027, China;
    bWenzhou Key Laboratory of Novel Optoelectronic and Nano Materials, Institute of Wenzhou, Zhejiang University, Wenzhou 325006, China;
    cDepartment of Electrical Engineering, Hanyang University, Seoul 04763, South Korea;
    dState Key Laboratory of Baiyunobo Rare Earth Resource Researches and Comprehensive Utilization, Baotou Research Institute of Rare Earths, Baotou 014030, China;
    eDepartment of Engineering Mechanics, Center for X-Mechanics, Zhejiang University, Hangzhou 310027, China
  • Received:2022-09-28 Revised:2022-10-19 Accepted:2022-10-19 Published:2023-06-10 Online:2023-06-05
  • Contact: *Center of Electron Microscopy and State Key Labo- ratory of Silicon Materials, School of Materials Science and Engineering, Zhejiang University, Hangzhou 310027, China. E-mail address:. jiangwei_wang@zju.edu.cn (J. Wang)
  • About author:1These authors contributed equally to this work.

Abstract: Element Sc is a promising candidate for optimizing the high-temperature mechanical properties of Al alloys. In this study, the Sc-solute, Al3Sc-vacancy and Al3Sc-solute interactions in aluminium are investigated extensively by using first-principles calculations. The correlation between the various interaction energies and the solute atomic size, and the Sc-solute compound formation energy has been evaluated. A negative correlation between the first nearest neighbour Sc-solute binding energies and the lowest Sc-solute compound formation energies has been identified, while the second nearest neighbour Sc-solute binding energies increase monotonically with the solute atomic size. Al3Sc precipitates can bind vacancy strongly at the specific atomic site, but their relatively low number density limits their influence on vacancy behaviours during the ageing period shortly after quenching. Compared to the atomic size, the trend for solute segregating at the interface between Al3Sc precipitate and Al bulk is more strongly related to the Sc-solute binding energy. The calculated results can clarify the available experimental observations for Al-Sc, Al-Cu, Al-Mg-Si and Al-Zn-Mg-Cu alloys, and it is hoped to guide the design of high-performance Al alloys.

Key words: Al alloys, First-principles calculations, Sc-solute binding, Al3Sc-vacancy interaction, Al3Sc-solute interaction