Evaluating the Flow Accelerated Corrosion and Erosion-Corrosion Behavior of a Pipeline Grade Carbon Steel (AISI 1030) for Sustainable Operations

Erosion-corrosion behavior of pipeline grade carbon steel alloy (AISI 1030) was investigated using a state-of-the-art jet impingement flow loop. Different impingement velocities (3 to 12 m/s) and angles (15 degrees, 30 degrees, 45 degrees, 60 degrees, and 90 degrees) were employed (with/without sand particles) to study the degradation behavior of this pipeline grade steel in 0.2 M NaCl solution at room temperature. Experiments were conducted for a duration of 24 h at room temperature. The maximum erosion-corrosion (EC) rate was observed at an impingement angle of 45 degrees at all velocities (3 to 12 m/s), as both the shear and normal impact stresses were of the same order of magnitude at this angle. At lower impingement angles, the effect of shear stress was more dominant and vice versa at higher impingement angles. The synergistic affect was found to be maximum at 45 degrees due to enhancement of erosion by corrosion and/or corrosion by erosion. Ploughing, deep craters, raised lips, dimples, micro-forging/plastic deformation, and extrusion were the dominant erosion-corrosion mechanisms as observed by Field Emission Scanning Electron Microscopy (FE-SEM). The maximum corrosion wear scar depth was found to be 57 mu m (average) at an impingement angle of 45 degrees, as measured using an optical profilometer. The obtained results are very significant and can be used in process parameter optimizations to enhance infrastructure reliability. These results will also be the part of in-house database to develop a comprehensive erosion and erosion-corrosion model for erosion-corrosion prediction of different materials under various operational conditions.