Although not a true surface technique, SEM-EDS often provides useful information in regard to surface corrosion mechanism. The ubiquitous nature, low cost, and ease of use of this technique cause it to be used as a tool in many failure analyses involving corrosion. This results in the necessity of almost no sample preparation for many different kinds of samples. Added advantages are greater magnification and depth of field. The contrast in backscattered electron images is mainly dependent on atomic number, so these images provide rough elemental distribution information.
Quantification can be quite good if appropriate standards are used.
This output can then be used to generate elemental distribution maps, or line scans. Some applications of SEM-EDS analysis are given in the metallography chapter of this manual.