Role of a chromium ion implantation on the corrosion behaviour of nickel in artificial sea water

Ni bulk specimens have been implanted with Cr ions (60 keV, 4.1016 ions/cm2), and classical corrosion experiments performed in artificial sea water by means of potentiodynamics i(E) and potentiostatics i(t) studies. Both experiments show that an important decrease of the current density is obtained in comparison with pure nickel. Moreover, a significant extension of the passivation region can be observed, with mainly an increase of the pitting potential. This behaviour is respectively related to an X-ray photoelectron spectroscopy (XPS) analysis of the passive film formed on Ni (Ni, Cr and O environments), and to previous results obtained on similar alloys