Localised corrosion behaviour of biomedical implant materials using electrochemical potentiokinetic reactivation and critical pitting potential methods

Abstract

In this study, localised corrosion properties of the biomedical grade Ti-Nb-Cu alloy and AISI 316 austenitic stainless steel specimens were investigated. Ti-Nb-Cu alloy specimens were produced by powder metallurgy method. Nb was used for beta-phase Ti stabiliser. Beta-Ti phase has low Young's modulus close to bone, higher wear resistance and biocompatibility. Cu was added to enhance sinterability of the Ti-Nb-Cu alloy; in addition, Cu is antibacterial. The AISI 316 austenitic stainless steel alloy was investigated as wrought (fully dense) specimens. Localised corrosion properties of the Ti-Nb-Cu and AISI 316 stainless steel alloys were examined by electrochemical potentiokinetic reactivation, critical pitting potential and Tsujikawa-Hisamatsu electrochemical tests in Hank's simulated body fluid solution. Effect of the Cu content of the Ti-Nb-Cu alloys and pH level of the simulated body fluid on the corrosion behaviour of the specimens was studied.