AUTHOR=Muñoz Andrés G. , Abdelouas Abdesselam , Alonso Ursula , Fernández Ana María , Bernier-Latmani Rizlan , Cherkouk Andrea , Gaggiano Roberto , Hesketh James , Smart Nick , Padovani Cristiano , Mijnendonckx Kristel , Montoya Vanessa , Idiart Andrés , Pont Arnau , Riba Olga , Finck Nicolas , Singh Ashutosh R. , King Fraser , Diomidis Nikitas TITLE=WP15 ConCorD state-of-the-art report (container corrosion under disposal conditions) JOURNAL=Frontiers in Nuclear Engineering VOLUME=Volume 3 - 2024 YEAR=2024 URL=https://www.frontiersin.org/journals/nuclear-engineering/articles/10.3389/fnuen.2024.1404739 DOI=10.3389/fnuen.2024.1404739 ISSN=2813-3412 ABSTRACT=A sealed container for the geological disposal of spent nuclear fuel and vitrified high-level waste is the only component of the deep geological repository that provides complete containment of radionuclides. As such, attention is focused on its lifetime. The lifetime of the container is influenced by materials degradation processes during disposal and is typically of the order of several millennia and, for some container materials, up to one million years. Designing, manufacturing, and predicting the performance of containers over such long periods requires an in-depth understanding of their materials properties, fabrication processes, and degradation mechanisms. Scientific and technological progress can improve both the performance of containers as well as the robustness of lifetime predictions. For many national radioactive waste disposal programs, optimization of these aspects is of primary importance. In this paper, the state of the art of complex coupled degradation processes, as well as the optimization potential of novel container materials is presented. Furthermore, the existing tools allowing the prediction of long-term barrier integrity are discussed.