10 – Void swelling and irradiation creep in light water reactor (LWR) environments

: Until 1993 it was assumed that swelling and irradiation creep were phenomena of little importance to light water cooled reactors. It is now recognized that swelling and irradiation creep are in progress in austenitic internals of pressurized water reactors (PWRs) especially, with boiling water reactors (BWRs) not being as vulnerable to these processes. Some manifestations of swelling and irradiation creep are already being observed in PWRs. Owing to the non-linear development of swelling with increasing neutron exposure, it is expected that consequences of swelling and irradiation creep will accelerate, especially as PWRs move beyond their original design lives of forty years.