Chemo-Mechanical Effect in Erosion-Corrosion Process of Carbon Steel Available to Purchase

In this work, the chemo-mechanical effect in slurry-erosion was investigated and an attempt was made to understand the mechanism of the corrosion-enhanced erosion. The chemo-mechanical effect was evaluated with the hardness degradation due to the presence of anodic current on the surface. The micro-hardness measurements of A1045 steel was determined in de-ionized water and in an aqueous solution of 1M NaHCO₃ while anodic current was applied. The results showed that the hardness decreased with increasing anodic current density and the relative hardness degradation (ΔHv / ΔHv₀) is a linear function of the logarithm of the anodic current density. The dependence of hardness drop on the anodic current density is almost independent of the corrosive media although the carbon steels displayed different polarization behavior in the test solutions used in the current experiments. The erosion and erosion-corrosion tests were conducted with A1045 steel in a slurry comprising 0.1M Na₂SO₄ aqueous solution + 30% sand under condition of cathodic protection or action of constant applied anodic current, respectively, and the steel was annealed at different temperatures to achieve different hardness. The degradation of mechanical erosion resistance with decreasing hardness implied that a synergistic mechanism would result from the chemo-mechanical effect. It was confirmed again by the test results. The material loss rate due to the corrosion-enhanced erosion increased with increasing applied anodic current density.