Abstract
Interaction energy values between substitutional 3d transition metal elements and interstitial carbon atom in α-Fe is obtained by the first-principles calculation method. Calculated values of interaction energy are in good agreement with experimental values reported for those of Co, Ni and Cu elements, showing a repulsive interaction experimentally. On the other hand, the interaction energy for such elements as Ti, V, Cr and Mn is estimated to be a repulsive characteristics, although the attractive interaction between them and a carbon atom is experimentally obtained. The cause for this contradiction is discussed based on a different formation energy of carbide precipitation from the atomic pair interaction energy.
