“…Other analytical tools, such as modern molecular spectroscopy, are capable of resolving compositional variations down to nm-scale, [56,57] but unfortunately are not often supported by proper SEM/EDS to confirm the observations, or they solely rely on SEM imaging. [53,58,59] Corrosion process steps, such as oxidation of metal matrix, are often concluded from grayscale SEM images without supporting elemental information.…”