• Citation: R. Gröger, V. Vitek, and A. Dlouhý (2020), "Effective pair potential for random fcc CoCrFeMnNi alloys", Modelling and Simulation in Materials Science and Engineering, 28(7), 075006. DOI: 10.1088/1361-651x/ab7f8b.
    Abstract: The single-phase equiatomic CoCrFeMnNi alloy is a random solid solution of five elements on the face-centered cubic lattice, whose pure constituents crystallize in very different structures and exhibit diverse magnetic properties. Due to the randomness of the alloy, 80% of nearest neighbor bonds are between unlike elements and thus the details of bonding in pure structures are less important. The elastic moduli of this alloy give rise to small Cauchy pressure C12 − C44, which suggests that the dominant part of bonding may be described by a simple pair potential. We test this hypothesis by developing a long-range Lennard-Jones potential in which the equilibrium crystal structures of pure constituents are taken as reference. The standard mixing rules for regular solutions are then adopted to obtain parameters for bonds between unlike elements in the quinary system. The transferability of this potential to quaternary CoCrFeNi, ternary CoCrNi, and binary FeNi alloys is investigated and the predictions compared with experiments and density functional theory calculations. By sampling over a large number of random configurations, we investigate the effect of compositional randomness on misfit volumes, energies of point defects and stacking faults, and the dislocation friction stresses experienced by moving edge and screw dislocations.

    Notes: R. Gröger notes that "This is the Mie n-2n potential, where n=6 was found to give the best results - it is the same as the Lennard-Jones 6-12 potential. These potential files contain parameterizations of the Co-Cr-Fe-Mn-Ni system intended for studies of compositionally complex alloys with spatially random distributions of individual elements. Although it was developed primarily for studies of the quinary fcc CoCrFeMnNi system, the paper above demonstrates that it can be used equally well for quaternaries and ternaries. We emphasize that the model ceases to be applicable for binary and unary systems, where most or all first neighbor bonds are between the same elements."

  • See Computed Properties
    Notes: These files were provided by Roman Gröger on Oct 23, 2021 and posted with his permission. The file mie.mod shows how to include these potentials in LAMMPS simulations via "include mie.mod".
    File(s):
Date Created: October 5, 2010 | Last updated: November 20, 2024