Corrosion Behaviors of Fe13Cr5Al4Mo Alloy in HighTemperature High-PressureWater Environments

FeCrAl alloys are promising candidate materials for accident-tolerant-fuel (ATF) claddings owing to their good high-temperature mechanical property, irradiation-swelling resistance, and hightemperature steam-oxidation performance. However, excellent corrosion resistance is also required in high-temperature high-pressure water environments when the alloys are used as ATF claddings. Therefore, in this work, the corrosion behavior of a Fe13Cr5Al4Mo alloy in 360 degrees C, 18.6 MPa deionized water and 360 degrees C, 18.6 MPa, 3.5 mg/L Li + 1000 mg/L B aqueous solution was studied. Results revealed that the weight gain and growth rate of the Fe13Cr5Al4Mo alloy were lower than that of the reference zirconium alloy, indicating a better corrosion property of the Fe13Cr5Al4Mo alloy. Moreover, an oxide film comprising Fe(Cr, Al) O-2(4) nanospinels formed on the Fe13Cr5Al4Mo alloy in both water environments, and Fe 3O 4 outer-oxide particles were observed in deionized water. The good corrosion performance of Fe13Cr5Al4Mo alloy was attributed to the compact spinel-oxide film, which could inhibit the diffusion of oxygen ions and metal cations. Adding Li + B into water changed the corrosion weight gain and oxide-film thickness of the Fe13Cr5Al4Mo alloy and impeded the formation of outer-oxide particles, which may be related to the high pH of alkaline Li + B aqueous solution and the interactions between Li+ and B3+.