Phosphoric acid anodization of Ti–6Al–4V – Structural and corrosion aspects

Electrodeposited anodic oxide coatings were produced on Ti–6Al–4V from phosphoric acid electrolyte. Different coatings were produced by varying the time periods. Structure of the coatings was analysed by X-ray diffraction, scanning electron microscopy and transmission electron microscopy. The coatings were exposed to simulated body fluid for a period of 1 month and the weight loss is used to calculate the corrosion rate. Electrochemical polarization and ac impedance studies were performed on the coatings in simulated body fluid and it was found that coatings produced from shorter times showed very good resistance to the attack by this medium.