J. Mater. Sci. Technol. ›› 2021, Vol. 61: 197-203.DOI: 10.1016/j.jmst.2020.05.061

• Research Article • Previous Articles     Next Articles

Coarsening kinetics and strengthening mechanisms of core-shell nanoscale precipitates in Al-Li-Yb-Er-Sc-Zr alloy

Yang Wanga, Shun Zhanga, Ruizhi Wua,b,*(), Nodir Turakhodjaevc, Legan Houa, Jinghuai Zhanga, Sergey Betsofend   

  1. aKey Laboratory of Superlight Materials & Surface Technology, Ministry of Education, Harbin Engineering University, Harbin 150001, China
    bCollege of Science, Heihe University, Heihe 164300, China
    cDepartment of Machine Building, Tashkent State Technical University, Tashkent 100056, Uzbekistan
    dMoscow Aviation Institute, National Research University, Moscow 109383, Russia
  • Received:2020-04-14 Revised:2020-05-05 Accepted:2020-05-14 Published:2021-01-20 Online:2021-01-20
  • Contact: Ruizhi Wu


The tailored nanoparticles with a complex core/shell structure can satisfy a variety of demands, such as lattice misfit, shearability and coarsening resistance. In this research, core-shell nanoscale Al3(Yb, Er, Sc, Zr, Li) composite particles were precipitated in Al-2Li-0.1Yb-0.1Er-0.1Sc-0.1 Zr (wt%) alloy through the double-aging treatment, in which the core was (Yb, Er, Sc, Zr)-rich formed at 300 °C and the shell was Li-rich formed at 150 °C. The coarsening kinetics and precipitate size distributions (PSDs) of Al3(Yb, Er, Sc, Zr, Li) particles aged at 150 °C previously aged at 300 °C for 24 h showed a better fit to the relation of <r>2kt and normal distribution, indicating that the coarsening of precipitates was controlled by interface reaction, not diffusion. The Orowan bypass strengthening was operative mechanism at 150 °C.

Key words: Al-Li alloys, Aging, Core-shell structure, Coarsening kinetics, Strengthening mechanisms