  The method of assessing porosity using images from scanning electron
microscopy is ineffective in situations where the substrate and the coating
have a significantly different average atomic number, which results in a
different contrast of backscattered electrons. For this reason, the analyzes
carried out to date were usually based on the manual distinction of important
microstructure elements, which was followed by selective thresholding. However,
this method depends on the subjective action of the researcher, and may result
in errors that are difficult to estimate. The presented method is based on the
simultaneous collection of both the image of backscattered electrons and
elemental maps obtained using an energy dispersive X-ray analyzer. Multivariate
comparative analysis of the matrix was used to characterize a technique of
distinguishing epoxy resin from a hydrated cement-based substrate. The proposed
algorithm significantly facilitates the detection of individual interface
components, and also makes comparative analyzes repeatable and reliable.
