TY - JOUR
T1 - Corrosion of aluminium in ordinary Portland cement paste
T2 - Influence of matrix porosity and the presence of LiNO3 corrosion inhibitor
AU - Caes, Sébastien
AU - Gurning, Alfred
AU - Li, Xiang
AU - De Souza, Valdir
AU - Kursten, Bruno
N1 - Score=10
PY - 2022/9/1
Y1 - 2022/9/1
N2 - The Belgian reactor 1 fuel cladding is made of aluminium. If disposed of in a geological disposal repository, aluminium could come into contact with ordinary Portland cement and is going to corrode to form hydrogen gas and aluminium hydroxide. In this study, the long‐term corrosion was evaluated by electrochemical impedance spectroscopy on metal embedded in cement paste immersed in saturated calcium hydroxide solution under anaerobic conditions. Mass transfer effects were investigated by embedding aluminium in cement paste with two different porosities. LiNO3 was also added to the systems to study its corrosion inhibiting effect. After high initial values, the corrosion rate rapidly declined to reach a steady state after a few days. After ~100 days, the corrosion rate was the lowest when cement paste possessing a low porosity with the addition of LiNO3 was used and the highest when cement paste with high porosity without LiNO3 was used. Finally, scanning electron microscopy–energy X‐ray dispersive spectroscopy revealed that the corrosion product layer was thicker than expected by electrochemical impedance spectroscopy measurements, while it is only composed of aluminium and oxygen. Aluminium was found to diffuse into the cement paste close to this corrosion product layer.
AB - The Belgian reactor 1 fuel cladding is made of aluminium. If disposed of in a geological disposal repository, aluminium could come into contact with ordinary Portland cement and is going to corrode to form hydrogen gas and aluminium hydroxide. In this study, the long‐term corrosion was evaluated by electrochemical impedance spectroscopy on metal embedded in cement paste immersed in saturated calcium hydroxide solution under anaerobic conditions. Mass transfer effects were investigated by embedding aluminium in cement paste with two different porosities. LiNO3 was also added to the systems to study its corrosion inhibiting effect. After high initial values, the corrosion rate rapidly declined to reach a steady state after a few days. After ~100 days, the corrosion rate was the lowest when cement paste possessing a low porosity with the addition of LiNO3 was used and the highest when cement paste with high porosity without LiNO3 was used. Finally, scanning electron microscopy–energy X‐ray dispersive spectroscopy revealed that the corrosion product layer was thicker than expected by electrochemical impedance spectroscopy measurements, while it is only composed of aluminium and oxygen. Aluminium was found to diffuse into the cement paste close to this corrosion product layer.
KW - Aluminium
KW - Anaerobic corrosion
KW - LiNO3
KW - Mass transfer limitation
KW - Ordinary Portland Cement
UR - https://ecm.sckcen.be/OTCS/llisapi.dll/open/50875293
U2 - 10.1002/maco.202213296
DO - 10.1002/maco.202213296
M3 - Article
SN - 0947-5117
SP - 1
EP - 13
JO - Materials and Corrosion
JF - Materials and Corrosion
M1 - 202213296
ER -