Fitting interatomic potentials consistent with thermodynamics: Fe, Cu, Ni and their alloys

Giovanni Bonny (1) , Roberto C Pasianot (2) , Lorenzo Malerba (3)

1 Nuclear Materials Science Institute
2 Materials Department
3 Nuclear Materials Science Institute

In computational materials science, many atomistic methods hinge on an interatomic potential to describe the material properties. In alloys, besides a proper description of problem specific properties, a reasonable reproduction of the experimental phase diagram by the potential is essential. In this framework, we develop two complementary methods to fit interatomic potentials to the thermodynamic properties of the alloy. The first method involves the zero Kelvin phase diagram and makes use of the concept of the configuration polyhedron. The second method involves phase boundaries at finite temperature and is based on the cluster variation method. As an example for both techniques, they are applied to the Fe-Cu, Fe-Ni and Cu-Ni systems. The resulting potentials are compared to those found in the literature and are found to reproduce the experimental phase diagram more consistently than the latter.

Mots clés: Physical Sciences

Giovanni Bonny, Roberto C Pasianot, Lorenzo Malerba. Fitting interatomic potentials consistent with thermodynamics: Fe, Cu, Ni and their alloys. Philosophical Magazine, 2009, 89 (34-36), pp.3451-3464. ⟨10.1080/14786430903299337⟩. ⟨hal-00541686⟩