Chromium Salt: A Review of Salt Formation, Hygroscopic Properties, and Impact on 316 L Corrosion in Hydrochloric Acid

ABSTRACT This article examines the impact of externally introduced chromium compounds on the localized corrosion of 316 L stainless steel in acidic chloride environments such as hydrochloric acid. While the corrosion resistance of 316 L relies on the formation of a chromium‐rich passive oxide layer, industrial conditions may expose the steel to various chromium species. Due to their hygroscopic nature, chromium salts can absorb moisture and form persistent thin electrolyte films on metal surfaces, creating aggressive microenvironments that promote localized corrosion. Despite their potential impact, the formation, stability, and corrosive effects of such deposits remain poorly documented. This review highlights the role of hygroscopic chromium salts in destabilizing the passive film of 316 L and increasing susceptibility to pitting and stress corrosion cracking in chloride media, emphasizing the need for further investigation to better assess corrosion risks in industrial environments.