Influence of Magnesium Ions in the Seawater Environment on the Improvement of the Corrosion Resistance of Low-Chromium-Alloy Steel

Sol-Ji Song; Jung-Gu Kim

doi:10.3390/ma11010162

Influence of Magnesium Ions in the Seawater Environment on the Improvement of the Corrosion Resistance of Low-Chromium-Alloy Steel

Materials (Basel). 2018 Jan 20;11(1):162. doi: 10.3390/ma11010162.

Authors

Sol-Ji Song¹, Jung-Gu Kim²

Affiliations

¹ School of Advanced Materials Science and Engineering, Sungkyunkwan University, 300 Chunchun-Dong, Jangan-Gu, Suwon 440-746, Korea. mysolgi@gmail.com.
² School of Advanced Materials Science and Engineering, Sungkyunkwan University, 300 Chunchun-Dong, Jangan-Gu, Suwon 440-746, Korea. kimjg@skku.edu.

Abstract

This study examined the synergic effect of alloying the element Cr and the environmental element Mg²⁺ ions on the corrosion property of a low-alloy steel in seawater at 60 °C, by means of electrochemical impedance spectroscopy (EIS), linear polarization resistance (LPR) tests and weight-loss tests. The Mg²⁺ ions in seawater played an important role in lowering the electron transfer of the rust layer in the Cr-containing steel. The corrosion resistance of the Cr-containing steel is superior to that of blank steel in Mg²⁺ ions containing seawater. XPS and XRD results indicated that the formation of MgFe₂O₄ and a mixed layer (Cr oxide + FeCr₂O₄ + MgCr₂O₄) improved the corrosion resistance of the low-alloy steel in the seawater.

Keywords: EPMA; corrosion; electrochemistry; low-alloy steel; rust layer.