Corrosion of aluminium: the contribution of hydrogen evolution Aqueous corrosion is an electrochemical reaction resulting in materials degradation, involving simultaneous oxidation of metal and reduction of species in a wet environment. The overall corrosion rate depends on how fast the two processes proceed. Although the reduction of oxygen is the most important cathodic reaction, for more reactive materials such as Al and Mg the reduction of hydrogen is thermodynamically allowed and could contribute to the overall rate. Now a team led by Michele Curioni at University of Manchester look at the hydrogen evolution behaviour of high purity aluminium and AA2024T3 alloy utilising coupled real-time hydrogen evolution and potentiodynamic measurements. Superfluous hydrogen evolution was observed during both anodic and cathodic polarisation and associated in both cases to local oxide disruption. The derived understanding of corrosion could enable us to develop new protection treatments.