Effects of Grain Boundary Engineering on the Corrosion Performance of Incoloy 800H in FLiNaK Melted at 850℃

To evaluate the effects of grain boundary engineering (GBE) on the corrosion performance of Incoloy 800H in FLiNaK melted at 850℃, GBE 800H alloy and 800H alloy were tested in static molten FLiNaK at 850℃ for 100 hours, respectively. SEM/EDS, FIB/SEM/EDS and electro-reading balance were used to measure the weight loss and micro-area element changes and observe corrosive morphology. The corrosion mechanism and process were analyzed. The results show that FLiNaK remarkably penetrated through grain boundaries; the corrosion depth and FLiNaK penetration through the grain boundaries of GBE 800H alloy are smaller than those of 800H alloy.