Construction Of An N-Body Fe-Cu Potential And Its Application In Atomistic Modeling Of Fe-Cu Solid Solutions

By means of the embedded-atom method, a Fe-Cu potential has been constructed through a newly mathematic form of cross potential. The newly constructed Fe-Cu potential has demonstrated to be more reliable than the five reported Fe-Cu potentials. Based on the Fe-Cu potential, the mechanical and thermodynamic properties and the structural stability of Fe-Cu solid solutions in the whole composition range are derived by molecular dynamics simulation. It is found that the heat of formation curves of the FexCu100 (- x) solid solutions with body-centered-cubic (BCC) and face-centered-cubic (FCC) structures intersect at the point of x = 65, implying that FexCu100 (- x) solid solutions with FCC and BCC structures are thermodynamically stable when 0 <= x <= 65 and 65 <= x <= 100, respectively. In addition, the derived lattice constants, structural stability, elastic constants, elastic moduli, heat capacity, and coefficients of thermal expansion of Fe-Cu solid solutions from the new Fe-Cu potential agree well with the data of the experiments, first-principles calculation, and the Miedema model. Published under license by AIP Publishing.