Corrosion of Be-based fusion-specific waste materials

Future fusion power reactors will generate activated metallic waste. Although the majority of this waste will be cleared or recycled, there will remain an important volume for which the solution may be surface or geological disposal. In current reactor concepts, the most important remaining fractions will be constituted by neutron irradiated beryllium, EUROFER, Li4SiO4, and tungsten. In particular, the beryllium presents a disposal problem because of its chemotoxicity in addition to its radiotoxicity. In order to support waste management decisions and environmental impact studies of fusion waste, data are needed on the corrosion of metallic wastes in a disposal environment. Therefore, we started a research programme aimed at providing such data. In a first phase, we focus on the corrosion of beryllium in argillaceous and cementitious environments. In these environments, the main form of corrosion attack on beryllium is pitting. To determine the susceptibility of Be to pitting, we used both short-term (potentiodynamic polarisation measurements) and long-term corrosion tests (monitoring the evolution of the corrosion potential over extended periods of time).