Irradiation and Oxygen Effects on Silicon Carbide Corrosion under Hydrothermal Conditions

Abstract

Ceramic material silicon carbide (SiC) is proposed to be used in nuclear reactors as a component material such as fuel cladding because of its high mechanical strength, resistance to irradiation, and chemical stability. However, the corrosion behavior of SiC under reactor operation conditions, one of the key factors that determines fuel and material performance, is not well understood. This paper reports the corrosion behavior of SiC at 300 °C under various pH values, redox conditions, and gamma irradiation doses. The results showed that dissolved oxygen concentration is a significant contributing factor to SiC degradation under the chemistry conditions of water cooled nuclear reactors. The corrosion rate of SiC can be well presented by empirical corrosion models. Overall, SiC is resistant to corrosion and irradiation in high temperature alkaline solutions, such as those encountered in the primary heat transport system in water-cooled reactors and could potentially be used as a structural material of advanced reactor components.