Physicochemical Interaction of EK-164 Steel with Uranium Dioxide During High-Temperature Irradiation

The aim of the investigations was to analyze the character and depth of the corrosion damage to EK-164 steel irradiated in contact with uranium dioxide at temperature 410-640A degrees C, maximum damaging dose 66-94 dpa, and burnup 10-13% h.a. These investigations were performed by means of full-scale electropotential scanning of irradiated elements as well as optical and scanning electron microscopy of the selected segments. Fuel-side intercrystallite corrosion of the steel at depth to 55 mu m was found at 450A degrees C. At irradiation temperature 580A degrees C in the presence of corrosive fission products, the damage acquired a mixed character involving continuous and intercrystallite corrosion to depth reaching 60 mu m. At intermediate temperature and maximum damaging dose, the corrosion depth in steel does not exceed 20 mu m.