A Modified Embedded-Atom Method Interatomic Potential for the Mg–Mn Binary System

Abstract

Magnesium, the lightest structural metal, needs to improve its strength and formability at room temperature for commercialization. Manganese is an alloying element that can improve the strength of magnesium through forming intermetallic compounds. However, its effect on the formability of magnesium has not yet been clarified. To identify the effect, an interatomic potential for the Mg–Mn binary system has been developed on the basis of the second nearest-neighbor modified embedded-atom method formalism. The Mg–Mn potential reproduces the structural, elastic, and thermodynamic properties of the compound and solution phases of its associated alloy system, consistent with experimental data and higher-level calculations. The applicability of the developed potential is demonstrated by calculating the generalized stacking fault energy for various slip systems of the Mg–Mn alloy.

Fig. 4 Calculated GSFE (mJ/m²) curves of pure Mg and Mg–Mn, models on the (a) basal plane along the <10-10> direction, (b) basal plane along the <11-20> direction, (c) prismatic plane along the <11-20> direction, (d) pyramidal I plane along the <11-20> direction, (e) pyramidal I plane along the <11-23> direction, and (f) pyramidal II plane along the <11-23> direction, using the present 2NN MEAM potential.