Influence of alloying elements on the pitting corrosion of dispersion-strengthened-high-strength steel in the marine atmospheric environment

Abstract

The effect of alloying elements in dispersion-strengthened-high-strength (DSHS) steel on the pitting corrosion in the marine atmospheric environment was investigated. The results showed that Cr, Ni and Mo showed a degree of bias in the rust layer with increasing exposure time, repairing defects in the rust layer and spreading to the interior of the rust layer. The generation of the protective product α-FeOOH was promoted, slowing down the corrosion reaction. The alloying elements made the rust layer cation-selective and the enhanced protective effect of the rust layer inhibits the vertical development of pitting corrosion at 25 °C. However, the vertical development of pitting corrosion in the late stages of corrosion at 65 °C with 3.5 wt.% NaCl was slightly increased.

Keywords

• Alloying elements
• Dispersion-strengthened-high-strength steel
• Pitting corrosion
• Marine atmospheric
• Rust layer