Semi-Empirical Parameterization of Interatomic Interactions and Kinetics   of the Atomic Ordering in Ni-Fe-C Permalloys and Elinvars
  Within the framework of the lattice-statics and static fluctuation-wave methods, the available energies of strain-induced interaction of interstitial-interstitial, interstitial-substitutional and substitutional-substitutional impurity atomic pairs are collected and analysed for f.c.c.-(Ni,Fe)-C solutions allowing for discrete atomic structure of the host-crystal lattice. The lattice spacings, elasticity moduli and/or quasi-elastic force parameters of the host-crystal lattice, and concentration coefficients of the dilatation of solid-solution lattice due to the respective solutes are selected as the input numerical experimental data used. The above-mentioned interaction energies prove to have non-monotonically decreasing and anisotropic dependences on discrete interatomic radius-vector, and themselves are strong and long-range. In all f.c.c.-(Ni,Fe)-base solutions, there is strain-induced attraction in many coordination shells. In general, the strain-induced interaction between impurity atoms in gamma-Fe is weaker than in alpha-Ni. The verification of applicability of the approximation of strain-induced interaction of impurities for f.c.c.-(Ni,Fe)-C alloys showed that it must be supplemented with additional short-range (electrochemical) repulsion in the first coordination shell. Nevertheless, in any case, the strain-induced interaction of impurity atoms must be taken into account for analysis of structure and properties of f.c.c.-(Ni,Fe)-base solutions. The Monte Carlo simulation procedures applied for constitution of a nanoscale Fe-C-austenite crystallite and based on analysis of the dependences of numbers of the different atomic configurations on C-C interatomic-interaction energies reveal correlation between the potential energy of such a modeling system and the numbers of iterations as well as Monte Carlo steps for the approach to constrained equilibrium. 
V. A. Tatarenko, S. M. Bokoch, V. M. Nadutov, T. M. Radchenko, and Y.   B. Park
cond-mat.mtrl-sci