About this Abstract |
Meeting |
12th International Conference on Magnesium Alloys and their Applications (Mg2021)
|
Symposium
|
12th International Conference on Magnesium Alloys and their Applications (Mg 2021)
|
Presentation Title |
Oxygen Reduction during Degradation of Magnesium |
Author(s) |
Cheng Wang, Di Mei, Mikhail Zheludkevich, Sviatlana Lamaka |
On-Site Speaker (Planned) |
Sviatlana Lamaka |
Abstract Scope |
Understanding fundamental mechanisms of magnesium degradation is vital for predicting its corrosion behaviour, developing new alloys and establishing reliable research methodologies. Hydrogen evolution reaction is widely regarded as the only cathodic process during corrosion of magnesium. Hence, tracing the amount of released hydrogen was thought to be a reliable measure of degradation rate. Recently, we have shown, by different methods, that oxygen reduction reaction (ORR) is important secondary cathodic reaction. In this work, we quantify rate of ORR for different grades of Mg.
Contrary to expected, oxygen consumption was the highest during corrosion of ultra-high purity Mg, and slower for rapidly corroding commercial-purity Mg. This phenomena was linked with the growth rate, thickness, morphology and permeability of Mg(OH)2 layer that blocks the access of dissolved oxygen to electrochemically active Mg/MgO interface. |
Proceedings Inclusion? |
Planned: At-meeting proceedings |