Formation of grain boundary segregations in alloy Fe-Cr-Ni during strong deformation and under radiation

Segregation of nickel in grain boundaries (GBs) in the Fe-Cr-Ni alloy induced by radiation (RIS) or plastic deformation (DIS) has been studied in the framework of a model which considers the generation of point defects, their mutual recombination, and absorption in GBs. It has been demonstrated that at sufficiently high rates of generation of point defects and in certain temperature ranges the achievement of a stationary state can be preceded by the stage of “rapid” segregation at which the Ni concentration in GBs reaches its maximum. Such mode of formation of segregations can be observed not only upon radiation (“rapid” RIS mode), but also under the conditions of severe deformation (cold rolling, equal-channel angular pressing); in the latter case, the segregates are inherited after the termination of deformation.