electrochemical characterization of a martensitic stainless steel

this paper focused on the characterization of electrochemical behavior of a martensitic stainless steel inthe acidic solutions. for this purpose, electrochemical parameters were derived from potentiodynamicpolarization, mott schottky analysis and electrochemical impedance spectroscopy (eis) techniques.the potentiodynamic polarization results showed that corrosion current density of aisi 420 stainlesssteel was decreased with the decrease in the concentration of solution. eis studies also showed thatas concentration was decreased, the measured value of polarization resistance was increased. thistrend was due to the decrease in the corrosion current density, which corresponded to potentiodynamicpolarization curves. mott schottky analysis revealed that passive films behaved as n-type and p-typesemiconductors at potentials below and above the flat band potential, respectively. also, mott schottkyanalysis indicated that the donor and acceptor densities were increased with solution concentration.