In vitro corrosion behaviour of titanium alloys without vanadium

The corrosion behaviour of three new non-toxic titanium alloys for use as biomaterials has been investigated. The corrosion current densities of these Ti alloys have low values, indicating a passive state that is stable with time. These values were calculated by using both direct and alternate current methods. The comparison with Ti-6Al-4V, widely used as biomaterial, shows slightly lower corrosion rates for the non V-containing alloys. To determine the pitting corrosion resistance, anodic polarisation curves were performed. Those alloys containing Zr, with very low passivation current densities, show the best behaviour. This indicates a low susceptibility to localised corrosion in these alloys. The chemical surface analysis performed on the samples suggests an influence of the passive layer composition on the passivation current density. (C) 2002 Elsevier Science Ltd. All rights reserved.