EFFECT OF NICKEL CONTENT OF 9CR-1MOVNB AND 12CR-1MOVW STEELS ON THE AGING AND IRRADIATION RESPONSE OF IMPACT PROPERTIES

Irradiating nickel-containing alloys in a mixed-spectrum reactor can simulate both transmutation helium and displacement damage expected in a fusion reactor first wall. Impact properties of 9Cr-1MoVNb and 12Cr-1MoVW steels doped with nickel were determined in the as-heat treated, thermally aged, and irradiated conditions to determine if nickel doping affects the behavior. Only limited property changes resulted from thermal aging or irradiation to 12 dpa at 450 to 550 degree C. Irradiation of the 12Cr-1MoVW steel at 390 degree produced severe degradation of impact properties. Nickel additions affected the unirradiated material properties, but radiation-induced changes were similar. The results indicate that nickel doping and subsequent irradiation in a mixed spectrum reactor is a viable method for simulating irradiation effects in a fusion reactor first wall.