Investigating the influence of metallic impurities on the properties of Cu coatings intended for used nuclear fuel containers
Canada’s use of nuclear power has led to an inventory of used fuel, which requires a strategy for safe, permanent containment. The current long-term disposal plan uses both natural and engineered barriers in a deep geological repository. A key engineered barrier in this concept is the used fuel container (UFC), made of copper-coated carbon steel. The Cu coating will be applied by two additive manufacturing techniques, electrodeposition (ED) and cold spray (CS) deposition. A major element in the UFC design is the establishment of specifications that will ensure efficient and cost-effective fabrication on the scale needed for the UFC, while avoiding any concerns related to performance. Since the CS-Cu coatings, proposed to cover the weld region of the container will inevitably contain trace metallic and non-metallic impurities, tolerances must be assigned. However, the absence of relevant studies in the literature suggests that the impacts of these impurities on the corrosion performance of Cu coatings remain unknown. The proposed research will develop an understanding of how impurities impact the corrosion of CS-Cu coatings, helping the Nuclear Waste Management Organization (NWMO) and the National Research Council (NRC) in assessing the performance of CS coatings and assigning specifications for large scale UFC fabrication.