Modified embedded-atom method interatomic potentials for Mg-Al-Ca and Mg-Al-Zn ternary systems

Al, Ca, and Zn are representative commercial alloying elements for Mg alloys. To investigate the effects of these elements on the deformation and recrystallization behaviors of Mg alloys, we develop interatomic potentials for the Al-Ca, Al-Zn, Mg-Al-Ca and Mg-Al-Zn systems based on the second nearest-neighbor modified embedded-atom method formalism. The developed potentials describe structural, elastic, and thermodynamic properties of compounds and solutions of associated alloy systems in reasonable agreement with experimental data and higher-level calculations. The applicability of these potentials to the present investigation is confirmed by calculating the generalized stacking fault energy for various slip systems and the segregation energy on twin boundaries of the Mg-Al-Ca and Mg-Al-Zn alloys, accompanied with the thermal expansion coefficient and crystal structure maintenance of stable compounds in those alloys. (C) 2020 Published by Elsevier B.V. on behalf of Chongqing University.