Effects of temperature and applied strain on corrosion of X80 pipeline steel in chloride solutions

Abstract

In this work, corrosion of X80 pipeline steel was investigated in 3.5 wt-% NaCl solutions with two different dissolved oxygen (DO) concentrations by electrochemical measurements and surface analysis techniques. The effects of temperature and applied strain on the steel corrosion were determined. Results show that an elevated temperature increases the corrosion activity of the steel and its corrosion reaction kinetics, which is mainly realised by the anodic reaction, rather than cathodic reaction. At a high DO concentration (i.e. 7 mg L −1 ) in the solution, the corrosion is diffusion-controlled. When the DO concentration is reduced to 3 mg L −1 , it becomes mixed controlled. The applied strain, although increasing the thermodynamic activity of the steel, does not obviously affect the corrosion of the steel due to the generation of corrosion scales, primarily γ-FeOOH, which provides somewhat protection to the steel and offsets the increased corrosion activity.

Coupling Effect of Hydrostatic Pressure and Erosion on Corrosion Behavior of X70 Steel in Simulated Seawater

“…The anodic polarization curve with a lower slope has no inflection point at 0.1 MPa; the cathode polarization curve hardly changes in the potential range of −0.64 V to −0.7 V. The diffusion of oxygen is considered the key to controlling the corrosion rate. 16,26,28,35 In addition, the open circuit potential is much higher than other conditions at 0.1 MPa, indicating that the metal has higher thermodynamic stability and a lower tendency for corrosion. 29 Pressure increases the corrosion rate of the X70 steel not only by affecting the thermodynamic stability of the material but also by promoting corrosion kinetics of the material.…”

Hydrogen Diffusion and Its Effect on Hydrogen Embrittlement in DP Steels With Different Martensite Content

“…The device and specimen shape were shown in Figure 1. The same method was also described in literature (Yuan et al, 2018). The strain rate was selected as 1 × 10 −6 s −1 to facilitate keeping the diffusion of hydrogen atoms in step with the dislocation movement, thereby resulting in hydrogen embrittlement (Kumamoto et al, 2019).…”

Spatial characteristics of stray current corrosion of reinforcing bars in pseudo concrete

“…In this case, the stray current field, ion movement, charge transition, and polarization of electrodes mutually interact in the corrosion domain 10 . In addition to stray current itself, many other factors can also affect the corrosion reaction, such as the resistivity of medium, 11 concentration of chloride ions 12 and temperature 13 …”