The used fuel container is a key barrier to isolate and contain used nuclear fuels in a deep geological repository (DGR). The consequences of hydrogen absorption into copper-coated containers has been recently raised in the safety assessment, hence it is necessary to investigate whether this process poses a risk to the long-term integrity of containers. In this study, electrochemical methods were used to produce hydrogen on different copper surfaces at various rates and for different durations. Consequently, surface analysis techniques, local probe techniques, and thermal desorption analysis (TDA) were applied to investigate hydrogen uptake by the copper metal. Analysis of the binding energy of hydrogen in copper reveals different trapping sites in the copper microstructure that are occupied by hydrogen atoms. The results to date show that the efficiency of hydrogen absorption by the copper is both current- and time-dependent.

7th International Workshop on Long-term Prediction of Corrosion Damage in Nuclear Waste Systems (LTC 2019)