From the use of the SEM methods for the evaluation of the organic matrix (figure 5a), which is obtained from the residues of the coating collected from the disbonded segments, it is clear that the elements that compose the sample correspond to the expected elements, which is reported in the specifications from the manufacturer. The fundamental application of XRD is the identification of crystalline samples; because this method is based on the optical interference between X-rays when they diffract in the atomistic array of the samples. This particular behavior is studied under the fulfilling of “Bragg law�, that allows identifying the conditions to diffract beams in a lattice. The use of this technique was to identify the iron phases and the possible identification of major contaminant materials. In figure 5b a common X-ray pattern is shown, where the peaks are associated to the expected iron crystals (alpha iron and hematite phases). The Fourier transformed Infrared spectroscopy (FT-IR) technique is based on the infrared light absorption capability of materials; the use of the vibrational analysis of molecules allows identifying species that can determine the presence of a surface component on the back of the FBE film, which could be the reason for the poor adhesion over the prepared substrate (Fig. 6a).
Figure 5. Spectroscopy analysis of collected samples by a) FT-IR and b) DSC.
In the laboratory analysis there were no evidences of any contaminating agent that could be the cause of the identified failures. The differential scanning calorimetry (DSC) technique is used to determine, between several other properties, the degree of cure of several coatings, FBE among them. The results of the analysis indicate that the product reached its cure satisfactory (Fig. 6b).