Influence of solution acidification on corrosion behavior of 316L SS in simulated crevice environment

Purpose The purpose of this paper is to investigate the influence of solution acidification on corrosion behavior of 316L stainless steel (SS) in simulated crevice environment. Design/methodology/approach In this paper, the double electrolytic cell device was used to simulate the different environment inside and outside of the crevice, and the effect of solution acidification inside the crevice on the crevice corrosion of 316L SS was investigated by electrochemical measurement and microstructure observation. Findings The results shows that the positive shift in the potential of the 316L SS inside the crevice due to the significant galvanic effect between the inside and outside of the crevice generate the passive effect facilitating the formation of passive films. However, the passive effect only mitigates the development of corrosion to a certain extent. In the weak acid environment, pitting corrosion occurs on the 316L SS inside the crevice. With the continuous acidification of the solution, the passive effect of 316L SS within the crevice weakens and corrosion intensifies. Finally, the environment factor plays the predominate role in the strong acid environment, leading to overall thinning of the 316L SS within the crevice. Originality/value The research findings further elucidates the mechanism of crevice corrosion of SS in seawater and provides valuable insights for the practical application of SS in marine engineering equipment.