Enhancement of pure titanium localized corrosion resistance by anodic oxidation

The corrosion behavior of commercially pure titanium (UNS R50400, ASTM grade 2) was investigated in presence of aggressive, bromides containing, species, reported to cause severe localized corrosion compared to chlorides. To enhance localized corrosion resistance of the metal, several surface treatments were performed. Samples anodized at potentials between 10 and 200 V were characterized in term of oxide thickness and morphology and tested with potentiodynamic analyses in ammonium bromide solution. Base metal was prepared both with etching and mechanical polishing pre-treatment, to enlighten the effect of pre-treatment sample preparation on post-treatment corrosion resistance.