The effects of dissolved hydrogen on the corrosion behavior of Alloy 182 in simulated primary water

The effects of dissolved hydrogen (DH) on the corrosion behavior of Alloy 182 in high temperature (320 °C) water were studied using in situ electrochemical measurements and ex situ surface analyses. The film resistance and thickness increased with decreasing DH. Under conditions of DH = 50 cm3/kg and 30 cm3/kg, the oxide film was very thin and predominantly consisted of Cr3+. At DH = 5 cm3/kg, the oxide film grew thicker, and the outer part consisted of NiO and spinel, with Cr3+ primarily located in the inner part. The underlying mechanism of stress corrosion cracking (SCC) susceptibility was considered.