Electrochemical corrosion performance of arc-directed energy deposited 308L austenitic stainless steel in sulfuric acid solution

This study investigates the electrochemical corrosion behavior and passive film characteristics of arc-directed energy deposited (arc-DED) 308L stainless steel in 0.1 M H 2 SO 4 solution compared to those of wrought 304 SS using a combination of DC and AC electrochemical techniques, supported by the point defect model (PDM). The results demonstrated that arc-DED 308L SS exhibited superior passivation behavior, with a lower corrosion current density and a more stable passive film compared to its wrought counterpart. Furthermore, the point defect density in the passive film formed on the arc-DED alloy was significantly lower. These improvements in corrosion resistance were attributed to the higher Cr content, increased dislocation density, and reduced defect diffusivity in the arc-DED alloy.