(POS-09) Corrosion Behavior of Hastelloy C-276 and SS316 in KCl-LiCl Molten Salt at 500°C: A Comparative Study

Jessika Rojas – Associate Professor, Mechanical and Nuclear Engineering, Virginia Commonwealth University

This study compares the corrosion behavior of flat coupon and cylindrical rod samples of Hastelloy C-276 and SS316 in a KCl-LiCl molten salt environment at 500°C. The samples were evaluated based on weight loss, surface morphology, and elemental composition to assess differences in degradation mechanisms due to geometry. Corrosion products and structural integrity were analyzed using scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), and X-ray diffraction (XRD). The results indicate that sample geometry significantly influences corrosion rates, with flat coupons exhibiting more uniform attack while cylindrical rods showed localized degradation due to differences in surface area exposure and salt flow dynamics. Hastelloy C-276 demonstrated superior corrosion resistance, forming a protective oxide layer, whereas SS316 suffered from chromium depletion and chloride-induced attack. These findings provide critical insights for optimizing material selection and sample geometry in high-temperature molten salt applications, particularly in nuclear reactors and thermal energy storage systems.