Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
1469627 | Corrosion Science | 2012 | 9 Pages |
Corrosion of magnesium alloys was studied during exposure to simulated body fluid (SBF). Microgalvanic processes dominate degradation morphology and formation of the corrosion/conversion layer. Localized corrosion with vigorous hydrogen evolution was observed at zirconium- and iron-rich precipitates that act as micro-cathodes. These are surrounded by volcano-shaped deposits of Mg(OH)2. Circular areas around cathodic centers were found to be protected from corrosion, while bulk degradation takes place in between. In SBF, conversion to a corrosion double layer was demonstrated. Differences observed for WE43 and pure magnesium (Mg) are discussed within the framework of a comprehensive model of the mechanisms of corrosion.
► Localized Corrosion of WE43 and pure magnesium under static exposure to SBF. ► Vigorous hydrogen evolution at particles, which act as micro-cathodes. ► Zr at WE43 and Fe at pure magnesium are dominant micro-cathodes. ► Protection of surrounding bulk and volcano-shaped depositions. ► A comprehensive corrosion model including a corrosion double-layer is proposed.