Role of electronic structure of grain boundaries in the processes of impurity segregation and particle precipitation

A calculation has been performed of the electronic structures of several clusters which imitate local environment of impurity atoms inside the grains and at their boundaries. In order to describe the structure of the latter the idea has been employed of the atomic structural units among which trigonal prismatic groups were chosen. The electronic states spectra have been obtained for a number of two- and three-component clusters containing atoms of Fe, Mn, V and C. On the base of the calculated energetic effects of these clusters formation the sequency of the segregation and particle precipitation processes in the austenite phase of HSLA-steels has been predicted