Molecular-dynamics simulations of binary Pd-Si metal alloys: Glass formation, crystallisation and cluster properties

Using Quantum Sutton-Chen potentials, Molecular Dynamics was used to obtain an atomistic description of melting, glass formation and crystallisation processes for palladium metal, metallic silicon and their alloys, from PdSi to Pd5Si. Glass formation and crystallisation were investigated using different cooling rates, by analysing the radial distribution function, enthalpy, density, volume, and diffusion coefficient. As expected, glass forms at high cooling rates, while crystallisation occurs at slower rates. The glass transition temperature was estimated from the Wendt-Abraham parameter vs temperature curves and the splitting of peaks in the radial distribution function. The effect of the Pd/Si ratio on the glass transition was studied by analysing the volume change during cooling of the Pd-Si alloys. The glass forming ability was found to increase with increasing Pd concentration in the alloys. Overall, our results reveal that Quantum Sutton-Chen potentials allow good descriptions of the melting, glass transition, and crystallisation during the heating and cooling processes.