Effect of dissolved oxygen on corrosion properties of F82H in high temperature pressurized water

Nakajima, Motoki; Hirose, Takanori; Tanigawa, Hisashi; Kawamura, Yoshinori

For blanket application, the structural material is required to be as thin as possible for tritium breeding. On the other hand, the pressure tightness is required to withstand 15 MPa of internal pressure. Therefore it is necessary to understand the corrosion mechanism in high temperature pressurized water. This work reports results of corrosion tests on a reduced activation ferritic/martensitic steel, F82H as a structural material for the blanket. Moreover, the effects of water flow and dissolved oxygen (DO) on corrosion properties were investigated using rotating disk specimen in autoclave. In previous study, it was reported that the weight loss by water flow becomes significant with lowering DO concentration. Based on the XRD and EPMA results, it seemed that the formation of FeO was effective for the suppression of weight loss. In this study, we discussed the relationship between stable oxide film and corrosion.