ELECTROCHEMICAL AND SURFACE MODIFICATIONS ON N-ION IMPLANTED T-6A1-4VIMMERSED IN HBSS()

The effect of nitrogen-ion implantation on the electrochemical behavio ur of Ti-6Al-4V in a simulated physiological solution (HBSS-Hank's bal anced salt solution) was studied by open-circuit potential versus time and cyclic polarization techniques, with the aim of characterizing be tter the surface prior to biological testing and to choose the most ap propriate nitrogen-ion fluence. Three fluences (10(15), 10(16) and 10( 17)ions/cm(2)) were used. The 10(16)ions/cm(2) N+ fluence produced the lowest corrosion rate under passive conditions. The highest fluence o riginated a large increase in the corrosion rate and inhibited the for mation of a calcium- and phosphate-rich layer on the electrode surface .