Nanoscale Failure Analysis of an Aluminium Alloy for Space Applications

This study has used focused ion beam (FIB) and transmission electron microscopy (TEM) to investigate the corrosion behaviour of AA7108 alloy at nanoscale. The high-resolution characterization allowed the analysis of microstructure evolution during corrosion process from microscale to nanoscale. This provides previously unseen details of trenching corrosion. For example, the dealloying of Fe-containing particle occurs immediately with the initiation of trenching corrosion. Based on these details, the relevant corrosion mechanisms are proposed.