Effect of cold rolling on the corrosion properties of low-alloy steel in an acid-chloride solution

This study examines the effect of a cold-rolling process on the electrochemical properties of low-alloy steel with different rolling percentages ranging from 0 to 80% in terms of the thickness reduction in an acid-chloride solution. From X-ray diffraction analysis, a cold-rolled texture is composed mainly of <111>//ND γ-fibers and the pole density increases with an increase in the degree of deformation. Scanning electron microscopy shows a decrease in the grain size of low-alloy steel with an increase in the degree of cold reduction. Moreover, the corrosion rate decreases with an increase in the degree of cold reduction due to the low-energy grain boundaries of the oriented grains. From potentiodynamic test, it was confirmed that the potential and the current density were decreased with increasing cold rolling reduction. In addition, electrochemical impedance spectroscopy results revealed an increase in the charge transfer resistance of the low-alloy steel with increased levels of cold rolling.