The influence of Desulfovibrio desulfuricans bacteria on a Ni-Ti alloy: electrochemical behavior and surface analysis

Evident influence of SRB on the surface of the NiTi alloy was observed, and the most intense effect was observed after 168 h of bioexposure. Biofilm-covered NiTi alloy was characterized by reduced resistance (Ri) and higher capacitance (Ci) in the barrier region of the oxide. However, some restoration of the protective properties of the passive film was observed in samples that had been exposed to bacteria for 720 h. XPS studies showed that no significant changes from the surface chemistry of the abiotic NiTi samples were induced by biofilm formation.