Theoretical evaluation of oxidation behavior of fuel cladding in light-waterreactor for prediction of fuel reliability
山本 泰功 Yasunori YAMAMOTO 森下 和功 Kazunori MORISHITA 岩切 友 Hirotomo IWAKIRI 金田 保則 Yasunori KANETA
First principle calculationFuel claddingOxidationOxide filmStressZirconiaZirconium
In order to establish the nuclear power system with sufficient safety, a lot of continuous efforts towards pursuing further plant safety should be made, not only at the plant design and construction stages, but also at the plant maintenance after start using as aging management. In many cases, plant aging are associated with material's degradation due to irradiation, cycle fatigue loading, high temperature, high pressure, etc. It is therefore very important that the degradation of materials under those severe environments should be accurately inspected and, ba sed on the obtained results the appropriate repair and exchange of materials should be done timely to keep the plant safety, which is so-called the condition-based maintenance. To do so, the methodology to predict the behavior of materials under severe environments on a basis of de gradation mechanism should be established. In the present study, as a first step towards the development of the methodology, the theoretical investigation was done, where atomistic calculations were performed to clarify the mechanism of degradation of fuel cladding due to oxidation.