Electron irradiation damage in austenitic stainless steels

Standard and Ti- and Nb-modified 316 SS specimens were irradiated with electrons in a high voltage electron microscope (HVEM) up to a dose of 40 dpa at 823 K. Void growth and carbide precipitate processes during irradiation were observed in situ and photographed. The experiment showed that 0.53% Ti-modified 316 SS had good resistance to void swelling, which is due to the small void size and low growth rate. The cold work did not increase the void swelling. In contrast, 0.49% and 0.78% Nb-modified 316 SS showed much higher void swelling than the others studied. However, the cold working of Nb-modified steels suppressed void swelling.