Interaction energies between substitutional 3d transition metal elements and an interstitial C atom in α Fe were estimated using the first-principles calculation. Calculated interaction energies were in good agreement with the experimental values reported for Co, Ni and Cu, showing a repulsive interaction experimentally. However, the interaction for such elements as Ti, V, Cr and Mn were also estimated to be repulsive, although the interaction between these elements and a C atom was known to be attractive experimentally. This apparent contradiction may be due to a difference in the formation energy of carbide precipitation from the atomic pair interaction energy.

Interaction between Substitutional and Interstitial Elements in α-Iron Studied by First-Principles Calculation. H.Sawada, K.Kawakami, M.Sugiyama: Materials Transactions, 2005, 46[6], 1140-7