VOID SWELLING OF PROTON-IRRADIATED FE-15CR-20NI TERNARY ALLOY

Studies have been made on the void swelling of solution-annealed Fe-15 Cr-20Ni alloy irradiated with 180 keV protons at temperatures from 723 K to 923 K. The displacement damage levels were 5; 10 and 20 dpa for samples preinjected with 10 appm He at room temperature, and 5 dpa for samples without He. In comparison with previously reported results of nickel-ion bombardment, void nucleation seemed to finish at earlier s tage of irradiation in samples injected with He. Subsequent void growt h was rather fast and, as a consequence, relatively large swelling was observed. Void microstructure and swelling were similar at 723 and 77 3 K between the samples with and without preinjected He, but they were quite different at 823 K probably due to helium effect which persists even at high temperatures. The results suggest that hydrogen introduc ed into the material by proton irradiation may play a significant role , which is similar and comparable to that of helium, in the microstruc ture evolution during irradiation at temperatures up to 773 K.