Abstract
The correlation between passive film and AC corrosion behavior of 2507 super duplex stainless steel (SDSS) has been investigated in NaCl solution under various AC current densities using the polarization curve, EIS test, Mott-Schottky curve and with immersion test. Additionally, the corrosion mechanism of passive film under AC interference was studied by X-ray photoelectron spectroscopy (XPS) and atomic force microscope (AFM). The test results indicate that the roughness of the passive film increases and the composition as well as electronic properties change under AC interference. Moreover, AC interference can enhance the dissolution of passive film, resulting in a non-uniform destructive effect to the film. The passivity of stainless steel degrades and pitting sensitivity increases as the increase of iAC. When iAC is less than 100A/m2, the pit initiation sites mainly concentrate on the austenite phase and the boundary between ferrite and austenite phase. However, a great number of pits occur on the ferrite phase while iAC equals to 200A/m2.
| Original language | English |
|---|---|
| Article number | 114072 |
| Journal | Journal of Electroanalytical Chemistry |
| Volume | 864 |
| DOIs | |
| Publication status | Published - May 1 2020 |
| Externally published | Yes |
Bibliographical note
Publisher Copyright:© 2018 Elsevier B.V.
ASJC Scopus Subject Areas
- Analytical Chemistry
- General Chemical Engineering
- Electrochemistry
Keywords
- 2507 SDSS
- AC current density
- AFM
- Corrosion behavior
- Passive film
