Elevated temperature molten salt corrosion study of SS304L austenitic boiler steel

The aim of this study is to investigate the high-temperature corrosion behavior of 304L stainless steel in the environment of various molten salt mixtures in the temperature range of 550–850°C. Weight change measurement has been done and characterization of corroded specimen was carried out using XRD, SEM/EDS techniques. Findings indicate that high chloride concentration salts affect the corrosion resistance adversely. The protective behavior of Cr2O3 layer deteriorated and its passivation is hindered at higher temperature owing to the chlorination-oxidation process. Fe2O3 and (Fe, Cr)xOy were found to be the major phases in the corrosion product. The salts were found to significantly affect the corrosion of 304L stainless steel in the following order: K2SO4 + 60% NaCl > Na2SO4 + 50% NaCl > 40% K2SO4 + 40% Na2SO4 + 10% KCl + 10% NaCl > Na2SO4 + 60% V2O5 > Air.