Corrosion behavior of aluminum alloy 5754 in cement‐based matrix‐simulating nuclear waste disposal conditions

Abstract

AbstractDepending 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.