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Potentiodynamic and cyclic voltammetric studies were carried out on nickel in borate buffered saline (pH = 8.49). The anodic excursion spans of nickel in borate buffer solution do not involve active/passive transition. The passive film starts to break down in the presence of Cl-ions, which causes pitting damage. The data reveal that the increasing Cl− concentration and solution temperature shifts the Epit to the active direction while the increasing in scan rate shifts the Epit to the positive direction. The pitting potential (Epit) shifted in a positive direction when increasing concentrations of Wo4−2 and MoO4−2 anions were added to a borate buffer solution containing Cl− ions, showing that the additional anions had an inhibitory influence on the pitting corrosion. While the NO3− anion is ineffectual as an inhibitor and rather speeds up pitting corrosion, the NO2− anion has a slight inhibitory impact on pitting corrosion. [ABSTRACT FROM AUTHOR]