Comparative study of electrochemical behaviour of CP-titanium and Ti–6Al–4V with other titanium based alloys for biomedical applications. (February 2014)

• Record Type: Journal Article
• Authors: Revathi, A.; Vijayalakshmi, U.; Geetha, M.
• Is Part Of: Materials technology. Volume 29(2014)Supplement B1
• Page Start: B49
• Page End: B53
• Publication Date: 2014-02
• Subjects: Titanium alloys, -- Potentiodynamic studies, -- Electrochemical techniques; Materials -- Periodicals; Materials science -- Periodicals; Materials -- Technological innovations -- Periodicals; 620.1105
• DOI: 10.1179/1753555713Y.0000000109
• Languages: English
• ISSNs: 1066-7857

Abstract

Abstract : The electrochemical behaviour of CP-Ti (commercially pure-Ti) and Ti–6Al–4V, commonly used implant materials, particularly for orthopedic and osteosynthesis applications, were investigated together with that of other Ti based alloys viz. Ti–13Nb–13Zr, Ti–15V–3Cr–3Al–3Sn, Ti–13Nb–20Zr, Ti–20Nb–20Zr and gum metal. The corrosion properties were evaluated through the analysis of the corrosion potential variation with time, potentiodynamic polarisation curves, and electrochemical impedance spectroscopy (EIS) test results. Very low current densities were obtained (order of nA cm −2 ) from the polarisation curves, indicating a typical passive behaviour for all investigated alloys in artificial physiological solution. The corrosion rates obtained were in the order CP-Ti>Ti–6Al–4V>Ti–15V–3Cr–3Al–3Sn>Ti–20Nb–20Zr>Gum metal>Ti–13Nb–13Zr. The EIS results clearly revealed the capacitive behaviour (high corrosion resistance) with phase angles close to −60° and high impedance values (order of 10 4 Ω cm 2 ) at low and medium frequencies, which are indicative of the formation of highly stable film on these alloys in the test solution. The obtained EIS spectra indicated two relaxation time constants and their interpretation in terms of an 'equivalent circuit' with the circuit elements representing the electrochemical properties of a bi-layered structure, was in good agreement.