Effects of solution composition on corrosion behavior of 13 mass% Cr martensitic stainless steel in simulated oil and gas environments

Abstract

The effects of CH3COONa and CO2 on the corrosion behavior of 13 mass% Cr martensitic stainless steel in simulated oil and gas environments were investigated with electrochemical and surface analysis techniques. The electrochemical results showed that a plateau region and sudden increase in the current density of the anodic polarization curves. The current density of the plateau region decreased with increasing CH3COONa concentrations. The pitting corrosion potential shifted to the positive direction with increasing CH3COONa concentrations, and shifted to a negative value by adding CO2. From the surface analysis, a Cr enriched layer had formed on the sample surface after immersion tests, and the thickness of this layer became thinner with increasing CH3COONa concentration. The surface analysis results after the immersion tests suggested the presence of CH3COO− or HCO3− on the surface.

Keywords

• 13 mass% cr martensitic stainless steel
• ch₃coona
• co₂
• xps
• gds
• oxide film structure