Effect of various impurity additives on the corrosion behavior of structural materials in NaCl-MgCl2 salt

This study evaluated the corrosion behavior of Ni-based structural materials in high temperature NaCl-MgCl 2 eutectic salt under varying impurity conditions. Nickel 201, Incoloy 800H, and Inconel 625 specimens were immersed in molten salts containing impurities at 650 °C for 500 h, followed by corrosion analysis using scanning electron microscope (SEM) and energy dispersive spectroscopy (EDS). The results showed that the type and concentration of impurities significantly affected the corrosion behavior, including internal attack and the characteristics of surface corrosion products. The corrosion resistance of the three alloys was highest for Nickel 201, followed by Inconel 625, and lowest for Incoloy 800H. These findings highlight the importance of controlling initial impurities in material selection for chloride based molten salt systems.