On the corrosion cracking of austenitic stainless steel in molten solar salt: Experiments and modeling

The mechanical behaviors of 304 and 316 L steels was investigated in air and in solar salt with different contents of chloride impurity under slow strain rate tensile (SSRT) tests using a novel experimental approach at 565 °C. Results show that the yield strength (YS) and ultimate tensile strength (UTS) are negligibly affected by the molten salt corrosion whereas the ductility decreases with increasing contents of chloride. Corrosion cracks initiate and propagate along the grain boundary due to its higher corrosion rate and incremental oxide rupture. Moreover, a damage model that captures the corrosion and chloride effects is proposed and validated.