Effects of salts and its mixing ratio on the corrosion behavior of 316 stainless steel exposed to a simulated salt-lake atmospheric environment

• Published in: Materials chemistry and physics 2022-01, Vol.276, p.125380, Article 125380
• Main Authors: Guo, Mingxiao, Tang, Junrong, Peng, Can, Li, Xiaohan, Wang, Chuan, Pan, Chen, Wang, Zhenyao
• Format: Article
• Language: English
• Subjects: 316 stainless steel; Atmospheric corrosion; Austenitic stainless steels; Corrosion; Corrosion effects; Corrosion products; Corrosion rate; Dehydration; Deposition; Diffusion barriers; Humidification; Hydroxides; Magnesium chloride; Mixed MgCl2; Mixing ratio; NaCl salts; Pits; Pitting corrosion; Salt-lake atmosphere; Stainless steel
• ISSN: 0254-0584; 1879-3312
• DOI: 10.1016/j.matchemphys.2021.125380

The effect of mixed salts and mixing ratio on the corrosion behavior of 316 stainless steel exposed to a simulated salt-lake atmosphere has been firstly investigated. 316 stainless steel was mainly analyzed by the evolution of surface morphologies, composition of corrosion products, statistics of pits depth and width and electrochemical measurements. The results indicated a layered double hydroxides (LDH) was detected in the corrosion products formed on 316 stainless steel surface under different salt deposition conditions, except under single NaCl deposition condition. When the mole fraction of NaCl was 0.75 in mixed MgCl2 – NaCl salts, the corrosion rate of 316 stainless steel was the fastest. The width of the pits formed on the surface of 316 stainless steel under mixed MgCl2 - NaCl salts deposition conditions was smaller than that under single MgCl2 deposition condition. The differences in corrosion rate and pit width size of 316 stainless steel under mixed MgCl2 - NaCl salts deposition conditions and single MgCl2 deposition condition were related to diffusion barrier provided by the neighboring NaCl crystals precipitated in thin liquid film during the humidification process and dehydration process. •316 SS exposed to salt-lake atmosphere were corroded severely.•Mixed salts and mixing ratio on corrosion behavior of 316 SS were investigated.•This work simulated natural environment based on actual atmospheric environment.•This work is useful for rapid assessment of the corrosiveness of 316 SS.