Stress-assisted corrosion behaviour of Hastelloy N in FLiNaK molten salt environment

Abstract The use of molten-salt–based energy production and storage systems requires high-temperature corrosion- creep-resistant structural materials. This study investigated the microstructure evolution corrosion characteristics Hastelloy N under working stress in a molten salt environment. Selective diffusion Cr at grain boundaries (GBs) degraded properties GBs, making them preferred locations for crack invasion. Stress further promoted accelerated GB carbide precipitation, thereby forming couple between matrix that facilitated expansion intergranular cracks into grains. These findings are useful providing advances design novel alloys with extraordinary property-microstructure stability combinations resistant to complex environments.