Interatomic potential to predict the glass-forming ability of Ni–Nb–Mo ternary alloys

Abstract

With the recently proposed formulation, an interatomic n-body potential was first constructed for the Ni-Nb-Mo metal system, and then applied to atomistic simulations to investigate the glass formation of the NiNb-Mo ternary alloys. The simulations not only clarify the atomistic process of the metallic glass formation but also predict for the ternary system of a quantitative composition region within which metallic glass formation is energetically favored. In addition, the energy difference between crystalline solid solution and disordered phase i.e., the driving force for a supersaturated solid solution to amorphize could be considered as an indicator of the glassforming ability (GFA) for a specific alloy. The GFAs of a series of Ni-Nb-Mo alloys were derived from the simulations, leading to pinpoint the Ni 55 Nb 30 Mo 15 alloy with superior GFA in this ternary metal system. The Ni 55 Nb 30 Mo 15 alloy can be considered as the optimized ternary metallic glass for thermal stability and manufacturability.

Atomistic Simulations to Predict Favored Glass-Formation Composition and Ion-Beam-Mixing of Nano-Multiple-Metal-Layers to Produce Ternary Amorphous Films

“…Based on the long-range empirical potential [55,56], the potential energy E i of atom i can be calculated as follows:…”

“…The fitted potential parameters of the Ni-Nb-Mo (fcc-bcc-bcc) system [55] are presented in Table 1. Furthermore, the potential parameters of the Ni-Zr-Mo (fcc-hcp-bcc) system [56] constituted by three major different crystalline structures are presented in Table 2.…”

“…The constructed long-range empirical potentials turn out to effectively determine the interatomic Table 3. Lattice constants (a, Å), cohesive energies (E c , eV), and bulk moduli (B 0 , Mbar) of B2 and L1 2 compounds in the Ni-Nb-Mo system derived from the potential (first line) and first-principle calculation (second line) [55]. …”

“…Figure 5. The structure factor S(q) of the Ni52Nb35Mo13 alloy derived from MD simulation [55] and the corresponding selected area diffraction (SAD) patterns [71]. The q1, q2 and q3 represent the first, second and third peak positions of the structure factor S(q).…”

“…The amorphization driving force (ADF), i.e., energy difference between the solid solution and amorphous phase, can be computed by [55] and the corresponding selected area diffraction (SAD) patterns [71]. The q 1 , q 2 and q 3 represent the first, second and third peak positions of the structure factor S(q).…”