B132 Experiments of Self-wastage Behavior due to Sodium-water Reaction in Steam Generator of Sodium-cooled Fast Reactor (2^ report)

Self-wastage comes from water/steam leak through the penetrating crack caused in the steam generator tube of sodium-cooled fast reactor. When the self-wastage proceeds to inside wall of tube, breach area and water leak rate will be larger, then, it will be likely to spread the affected area caused by sodium-water reaction. It is very important to clarify the self-wastage behavior for locally affected region and detection of the water leak in real plant. In the 1^ report, the authors have performed the self-wastage experiments for the pinhole type micro crack. In this report, fatigue crack type self-wastage experiments were carried out to evaluate the effect of wastage form/geometry and water leak rate, it was confirmed that initial defect geometry, such as pinhole and fatigue crack, does not strongly influence to self-wastage rate.