Spent nuclear fuels are stored after their use in reactors. Dry storage can favor the appearance in the fuel rod cladding of a mechanical-chemical phenomenon referred to as Delayed Hydride Cracking (DHC). DHC is divided into three iterative steps: (i) diffusion of hydrogen in solid solution; (ii) precipitation of this hydrogen into hydrides; (iii) brittle fracture of hydrides. To assess the risk of occurrence of this phenomenon, the fracture toughness is determined by calculating the stress intensity factor below which DHC is not observed (KIDHC) based on an experimental procedure and a numerical model.
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