Studies on corrosion behaviour of low carbon steel canister with and without γ-irradiation in China’s HLW disposal repository

Abstract

Carbon steel is the candidate material of the canister in high level radioactive nuclear waste disposal repository in China. The corrosion behaviour of X65 grade low carbon steel exposed to bentonite thermally aged at 363.15 K after exposure to 0 and 2.98 kGy h−1 γ-irradiation for 1007 h was studied using optical microscopy, scanning electron microscopy, energy dispersive X-ray spectroscopy, X-ray diffraction, micro-Raman spectroscopy (μ-Raman), weight loss measurements and white-light interferometry. The results show that 2.98 kGy h−1 γ-irradiation causes the formation of new phases of siderite and maghemite, and accelerates the corrosion rate by ∼33%.This paper is part of a supplement on the 6th International Workshop on Long-Term Prediction of Corrosion Damage in Nuclear Waste Systems.