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The rapid solidification of Pd-Ni alloys is studied with the constant-pressure and constant-temperature (TPN) and the constant-volume and constant-temperature (TVN) molecular dynamics technique to obtain an atomic description of glass formation in the alloy. Quantum Sutton-Chen potential for Pd-Ni binary system is applied in the simulations. We present some thermodynamic and structural results from simulations of such glasses over a range of compositions. The structural properties are analyzed by means of pair distribution function, volume, and enthalpy as a function of temperature and concentration at the cooling rates ranging from 5 K/ps to 0.05 K/ps to see whether the Pd-Ni alloy goes into glass formation or it crystallizes. The relation between the cooling rate and glass transition temperature is revealed. We have also investigated shear viscosity in the supercooled regime. Its temperature dependence indicates fragile-liquid behavior, typical of binary metallic glasses. The results shows that the atomic mismatch and having the eutectic composition are important parameters to form glassy state. [ABSTRACT FROM AUTHOR]

Abstract: The mechanical and thermodynamical properties of Pd, Ag pure metals and especially PdxAg1−x alloys are studied by using the molecular dynamics simulation. The effects of temperature and concentration on the physical properties of PdxAg1−x are analyzed. Sutton–Chen (SC) and quantum Sutton–Chen (Q-SC) many-body potentials are used as interatomic interactions which enable one to investigate the thermodynamic, static, and dynamical properties of transition metals. The calculated results such as cohesive energy, density, elastic constants, bulk modulus, pair distribution functions, melting points and phonon dispersion curves of Pd, Ag and PdxAg1−x are in good agreement with the available experimental data at the various temperatures. The predicted melting points of Pd, Ag and their binary alloys from Q-SC potential parameters are closer to experimental values than the ones predicted from SC potential parameters. [Copyright &y& Elsevier]