Effect of localized corrosion on the galvanic corrosion of nitinol and dental alloys
Abstract
Purpose
The purpose of this paper is to evaluate the galvanic corrosion of nitinol orthodontic wires with six dental alloys in artificial saliva and consider the effect of initiated localized corrosion and real surfaces of anode and cathode on galvanic current.
Design/methodology/approach
Linear polarization and cyclic polarization curves for each alloy in de‐aerated Duffo and Castillo's artificial saliva are obtained. Galvanic corrosion investigation is conducted by polarization curve intersection and mixed potential theory methods. In order to verify the initiation of localized corrosion, scanning electron microscopy is used.
Findings
Initiation of localized corrosion on the anode increases the galvanic current up to 45 times and therefore considering the effect of localized corrosion on galvanic corrosion is necessary. Placing stainless steel brackets or Aristaloy amalgam in direct contact to nitinol arch wire is not recommended.
Originality/value
In order not to underestimate the galvanic corrosion between two alloys, it is recommended to consider the effects of localized corrosion and anode/cathode surface area ratio. In this paper, an electrochemical method for estimating these factors is proposed.
Keywords
Citation
Afshar, A., Shirazi, M., Rahman, M. and Fakheri, E. (2009), "Effect of localized corrosion on the galvanic corrosion of nitinol and dental alloys", Anti-Corrosion Methods and Materials, Vol. 56 No. 6, pp. 323-329. https://doi.org/10.1108/00035590911000304
Publisher
:Emerald Group Publishing Limited
Copyright © 2009, Emerald Group Publishing Limited