Corrosion Behavior of Cr-Mo Alloy Steel in Direct Contact with Elemental Sulfur

The chemical degradation of stainless steel components in sulfur-containing environments is a major concern in oil and gas production. 4130 Cr-Mo alloy steel is widely used as tubing and tubular components in sour services. According to the previous research in aqueous conditions, contact of solid sulfur with alloy steel can initiate catastrophic corrosion problems. This paper discusses elemental sulfur corrosion of Cr-Mo alloy steel in 3.5% sodium chloride solution at pH 2 and 5 during 20 and 30 hours immersion time. The corrosion behavior was monitored by potentiodynamic polarization technique during the experiments. Energy Dispersive X-ray Spectroscopy (EDS), and Scanning Electron Microscopy (SEM) have been applied to characterize the corrosion products after each experiment.