Understanding the Corrosion of Mg and Mg Alloys

This article summarizes current, fundamental knowledge of the corrosion of magnesium, and highlights some latest developments. Mg is a most reactive metal. The high available reaction energy, and because the simultaneous exchange of two electrons is forbidden by quantum mechanics, means that there is a highly reactive intermediate that can chemically split water. Thus, part of the corrosion rate cannot be measured with electrochemical techniques. Furthermore, the evolving hydrogen can insulate part of the corroding surface from electrochemical measurement. It is best practice to simultaneously use several measurement techniques, and to compare the measured corrosion rates in the same units.