A pair potential was constructed in order to describe Fe-Cu interactions. The potential was fitted to the vacancy-Cu binding energy of body-centered cubic Fe, and to the dilatational properties of coherent Cu precipitates. The properties of Cu point defect complexes in the body-centered cubic Fe matrix, and interactions between point defects and precipitates were calculated. The binding energy of a Cu atom to a small coherent precipitate (of up to 180 Cu atoms) was estimated as a function of the precipitate size. This was found to be a non-monotonic function in the case of small precipitates. The dilatational and structural properties of coherent precipitates were studied, and the relaxation of the matrix around precipitates was determined. The vacancy/precipitate interaction energy, and vacancy migration near to (and within) precipitates were also considered. It was found that the anisotropy of vacancy migration and interaction was related to the anisotropy of relaxation of matrix atoms around a precipitate.

J.N.Osetsky, A.Serra: Philosophical Magazine A, 1996, 73[1], 249-63