Electrochemical investigation of Fe- and Zr-based alloys in standard conditions and under gamma irradiation in contact with H2O2

Abstract

Radiation induced corrosion is a major problem for the longevity of nuclear power plants, and the research into this field is hampered by the requirement to accurately simulate reactor conditions in experiments. This study attempts to electrochemically investigate the interaction between hydrogen peroxide (H2O2) and the alloys AISI 441 and Zircalloy-2 (Zry2), both under standard conditions and under γ irradiation. The results from the linear scan voltammetry (LSV) indicate that the anodic oxidation reaction between AISI 441 and H2O2 might be catalyzed by γ irradiation. Whereas the cathodic reduction reaction may be inhibited by the radiation. With regards to Zry2 the anodic LSV results show a possible surface area limitation on the reaction. The cathodic experiments highlight the chemical inertness that the alloy is known for, though there appears to be a inhibitory effect of γ radiation upon the evolution of hydrogen. These findings highlight the greater sensitivity of AISI 441 to radioactive environments, which may have implications for material selection in reactor design.