Relation between the vacancy migration energy in austenitic steels and their resistance to irradiation-induced swelling

Abstract

The effect of the vacancy migration energy in austenitic steels on their resistance to irradiation-induced swelling is studied. ChS68 and EK164 steels, whose energies of vacancy migration differ by 0.1 eV from each other, are used to show that the steady-state vacancy concentration in the EK164 steel is less than that in the ChS68 steel. This difference explains why the critical pore nucleus diameter (after which pore grows owing to an unbalanced vacancy flow) in the EK164 steel is larger than that in the ChS68 steel. As compared to the ChS68 steel, a larger number of helium atoms and, correspondingly, a longer incubation swelling time are required for such a pore nucleus to form in the EK164 steel.