Electrochemical Behavior of Cobalt-Chromium Alloy as Biomaterial in Different pH Environments

Abstract:

The paper discusses the electrochemical interactions of Co-Cr alloy with different physiological solutions and organic substances, containing different ions and different pH values, which should play a key role in the materials lifetime. The physical and chemical reactions are numerous and the passivity of the Co-Cr alloy is submitted to the influence of the liquid environment. Some electrochemical investigations were carried out for understanding and predicting the passivity and the corrosion resistance of Co-Cr alloy in three types of simulated body fluids (SBF), namely Fusayama Meyer artificial saliva (pH=5), Hank’s solution (pH=7.4), Ringer's solution (pH=6.6) and citric acid as organic solution. The reason of using another type of environment (other than SBF), such as citric acid is that this medium is a powerful oxidant and has a lower pH value (pH=1.8). This acid environment can influence the state (the formation and growth) of the oxide layer on the surface of the alloy. Research has shown different behavior of the cobalt chromium alloy according to the pH, the chloride content and the oxidizing nature of the environment. Co-Cr alloy biomaterial, immersed in four aqueous media reveals that there are different levels of stabilization of the potential and different current densities depending on the pH value. The Co-Cr alloy biomaterial is very sensitive to localized corrosion (pitting) in Hank solution.

• Periodical: Advanced Materials Research (Volume 1139)
• Pages: 59-63
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.1139.59
• Online since: July 2016
• Authors: Lidia Benea*, Valentin Marian Dumitraşcu, Eliza Dănăilă
• Keywords: Biomaterial, Co-Cr Alloy, Corrosion, Cyclic Voltammetry, Dentistry, Electrochemical Impedance Spectroscopy, Open Circuit Potential, pH, Physiological Solutions

References

[1] P. Bartolo, J. -P. Kurth, J. Silva, G. Levy, A. Malshe, K. Rajurkar, M. Mitsuishi, J. Ciurana, M. Leu, CIRP Ann. Manuf. Technol. 61, (2012) p.635.

DOI: 10.1016/j.cirp.2012.05.005

[2] S. Madhavi, S.R. Allahkaram, J. Alloys Compd. 635, (2015) p.150.

[3] Z. Guo, X. Pang, Y. Yan, K. Gao, A.A. Volinsky, T. -Y. Zhang, Appl. Surf. Sci. 347, (2015) p.23.

[4] G. Saravanan, S. Mohan, J. Alloys Compd. 522, (2012) p.162.

[5] J.J. Ramsden, D.M. Allen, D.J. Stephenson, J.R. Alcock, G.N. Peggs, G. Fuller, G. Goch, CIRP Ann. Manuf. Technol. 56, (2007) p.687.

DOI: 10.1016/j.cirp.2007.10.001

[6] Y.S. Li, K. Wang, P.P. He, B.X. Huang, P. Kovacs, J. Raman Spectrosc. 30, (1999) p.97.