engleski

Stress Generation during the Growth of Anodic Oxide Films on Titanium-Aluminium Alloys

The formation of stable passive oxide films is critical to the design engineering of new biomaterials for orthopaedic implants. The growth of anodic oxide films on titanium, Ti6Al4V and Ti6Al6Nb alloys has been investigated in physiological solution at 37^o C. During anodic film growth, the electric field strength within the film was of the order of 107 V cm^-1. This electric field exerts significant electrostriction on the film and yields high internal compressive stress of the order of a few GPa. The observed transformation from amorphous to crystalline structure at 2 V for all investigated materials and the onset of pitting corrosion and passivity breakdown for the Ti6Al4V alloy are accompanied by the appearance of compressive stress within the oxide film. The results are discussed with respect to the relevant reactions occurring at the metal/oxide and oxide/electrolyte interface during oxide growth.

biomaterials, anodic oxide film, electric field, compressive stress, structural transformation, passivity breakdown

Rad je kao poster prezentiran na skupu 50th International Society of Electrochemistry Meeting, održanom od 05-10.09.1999., Pavia, Italija ; kao prosireni sažetak objavljen u Knjizi sažetaka ; Pavia, 1999., str. 832.