Solute-second phase interaction for Mg, Ag and Zn in Al–Li alloys

ABSTRACT

Early experiments have shown the promises of alloying with Mg + Ag (or Mg + Zn) on the performance of Al–Li alloys. To better understand the interaction between solutes and second phases in Al–Li alloys, Mg, Ag and Zn segregation to Al/δ′ interface as well as their substitution in δ′ bulk were investigated at the atomic level using first principles modelling and calculations. Energetics results and local charge analyses revealed that Mg, Ag and Zn can segregate to Al/δ′ interface by different preference, but have no significant influence on the interface adhesion. Ag and Zn can also dissolve into δ′ bulk, and enhance the local metallic bonding with nearest-neighboring Al atoms. Based on these results, a multi-fold benefit mechanism was suggested for the combined alloying with Mg + Ag (or Mg + Zn) in Al–Li alloys.

KEYWORDS:

• Al–Li alloy
• Al₃Li
• interface
• segregation
• first principles

Acknowledgements

The authors would like to acknowledge the financial support from the Natural Science Foundation of China (No. 51971249), the Natural Science Foundation of Shandong Province (No. ZR201808200231), the Project of Shandong Province Higher Educational Youth Innovation Science and Technology (2019KJA019), and the Science and Technology Program of High Education of Shandong Province (grant number J18KA037, J18KA039).

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This work was supported by National Natural Science Foundation of China [grant number No. 51971249]; the Science and Technology Program of High Education of Shandong Province [grant number No. J18KA039, J18KA037]; Natural Science Foundation of Shan Dong Province [grant number No. ZR201808200231]; the Project of Shandong Province Higher Educational Youth Innovation Science and Technology [grant number No. 2019KJA019].