MD study of the glass transition in binary liquid metals: Ni6Cu4 and Ag6Cu4

The structure, thermodynamic and kinetic evolution of the binary Ni6Cu4 and Ag6Cu4 liquids during a rapid cooling process were studied in detail by using the molecular dynamics (MD) simulation method. The Gibbs free-energy difference between the supercooled liquid and the crystal (ΔGlc) for the pure metals Ni and Ag and for alloys Ni6Cu4 and Ag6Cu4 is calculated. A time-temperature-nucleation diagram for Ni6Cu4 is constructed based on the temperature dependence of the characteristic relaxation times. The results indicate that the driving force for the crystallization ΔGlc plays an important role in the glass transition process. The increase of the metallic glass forming ability (GFA) is in consistent with the decrease of ΔGlc.