Molecular dynamics study of Cu-Pd ordered alloys

Journal of Achievements in Materials and Manufacturing Engineering 01/2008;
Source: DOAJ

ABSTRACT Purpose: The goal of the paper is to study the molecular dynamics of Cu-Pd ordered alloys.Design/methodology/approach: The thermal and mechanical properties of Cu, Pd pure metals and their ordered intermetallic alloys of Cu3Pd(L12) and CuPd3(L12) are studied by using the molecular dynamics simulation. The melting behavior of the metals considered in this work is studied by utilizing quantum Sutton-Chen (Q-SC) many-body potential. The effects of temperature and concentration on the physical properties of Cu-Pd system are analyzed.Findings: A wide range of properties of Cu, Pd pure metals and their Cu3Pd and CuPd3 ordered intermetallics is presented. It was found that this potential is suitable to give the general characteristics of the melting process in these systems. Practical implications: The simulation results such as cohesive energy, density, elastic constants, bulk modulus, heat capacity, thermal expansion and melting points are in good agreement with the available experimental data and other theoretical calculations.Originality/value: To the best our knowledge this work presents, for the first time, a wide range of physical properties of alloys focusing on Cu-Pd ordered compounds.

  • [Show abstract] [Hide abstract]
    ABSTRACT: In this study, the molecular dynamics (MD) simulation technique is employed to investigate the influence of nanowire diameter on the elastic properties of pure Cu and Pd as well as Cu–20%Pd, Cu–40%Pd, Cu–60%Pd and Cu–80%Pd (at%) nanowires. The interaction between atoms Cu–Cu, Pd–Pd as well as Cu–Pd were calculated by Quantum Sutton–Chen (Q–SC) many body potential. The temperature and pressure of the system were controlled by Nose–Hoover thermostat and Berendsen barostat, respectively. The effect of the nanowire thickness on the cohesive energy, Poisson ratio, elastic stiffness constants (C11, C12 and C44) as well as the bulk modulus (B) was studied in NPT ensemble at 10 K. The obtained results show that there is an initial change in the mechanical properties of B, C11 and C12 with the thickness of the nanowire, following which the properties remained unchanged as the nanowire grows in size. However the C44 value was found to be almost independent of nanowire thickness. Moreover, The MD results have shown the cohesive energy per atom and Poisson ratio depends to diameter of nanowires.
    Composites Part B Engineering 01/2012; 43(1):10–14. DOI:10.1016/j.compositesb.2011.04.023 · 2.60 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: First principles calculation based on density functional theory is used to comparatively investigate phase stability, elastic properties, and electronic structures of PdH and PdCuH phases with various H concentrations. Calculation shows that PdCuHx phases possess smaller heats of formation than corresponding PdHx as 0 � x < 0.105, whereas PdHx phases are energetically more stable when x exceeds 0.105. It is also revealed that the volume expansion of PdCuH phase as a result of H addition is smaller than that of PdH at low H concentrations, implying that the alloying of Cu could lower hydrogen embrittlement of PdH. Furthermore, it is indicated that Cu should have an important effect of solid-solution strengthening in the Pd lattice, and the PdCuH phase has bigger E, G, and G/B values than PdH. The calculated results are discussed in terms of electronic structures, and are in good agreements with experimental observations in the literature.
    International Journal of Hydrogen Energy 11/2013; 38(36):16485–16494. DOI:10.1016/j.ijhydene.2013.10.020 · 2.93 Impact Factor

Full-text (2 Sources)

Available from
May 21, 2014