Investigation on static and dynamic corrosion behaviors of thermal energy transfer and storage system materials by molten salts in concentrating solar power plants

With the emergence of the concentrating solar power (CSP) technology, the corrosion behaviors of potential materials applied in thermal energy transfer and storage system attract tremendous attentions. Corrosion behaviors of X80 carbon steel, 304, 316L stainless steels, and 600, 825 nickel alloys in the molten salt mixtures at different temperatures were comparatively investigated using immersion tests under static and dynamic states and electrochemical scans. The corrosion resistance of stainless steels and nickel-based alloys in molten salt at 530 degrees C followed the sequence of 304<316L<600<825. The aggressiveness of different molten salt mixtures was compared, indicating that the ternary system was more aggressive than the binary system. The corrosion aggressiveness under dynamic state was more severe when compared to that under the static state. The N-2 atmosphere was proved to be protective for alloys immersed in high temperature molten salts.