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In France, deep geological disposal is considered for the storage of high and intermediate‐level long‐lived radioactive wastes. For aluminium, the possibility to encapsulate the wastes in a cement‐based matrix is studied. However, cement being an alkaline environment, aluminium can lose its passivity, starts to corrode leading to hydrogen evolution in the infrastructures and generate a possible explosive hazard after decades of storage if hydrogen can accumulate somewhere in the facility. It is therefore necessary to study the corrosion behaviour of aluminium in the different cements considered for the encapsulation to estimate the possible amount of hydrogen that could be generated through corrosion and design the cement capsules accordingly. This work mainly focused on the reaction occurring at the aluminium‐cement interface. Raman spectroscopy did not highlight significant differences in the nature of the corrosion products forming at the cement/aluminium interface, leading to the conclusion that it is not the chemistry of the cement that is the key factor controlling the corrosion rate but rather the physical properties of the cement matrix. [ABSTRACT FROM AUTHOR]

Depending on the lifetime and level of radioactivity of radioactive wastes, different disposal facilities are considered. Though low‐ and intermediate‐level short‐lived waste can be disposed in surface disposal facilities, deep geological disposal is considered for high‐ and intermediate‐level long‐lived waste. In France and Belgium, long‐term disposal is studied in clay host rock media. For aluminum, the disposal concept is based on encapsulation of the waste in a cement‐based matrix. It is also well‐known that aluminum is prone to severe corrosion in sufficiently alkaline environments leading to possible hydrogen production. To ensure the safety of the disposal facilities and the integrity of the cement capsules, the amount of aluminum that is disposed in each waste package must be specified and is limited to mitigate the level of hydrogen production by aluminum corrosion. In the present study, the corrosion resistance of an aluminum alloy (grade EN‐AW‐5754/H111) in two different cement matrices was studied in different configurations at room temperature. In each case, the evolution of hydrogen production was monitored to address the corrosion rate variation versus time. [ABSTRACT FROM AUTHOR]