2.2.2. Coating Thickness Analysis

Coating thickness was assessed by analyzing cross-sections obtained (using the process described in Section 2.2.1) from the coated end mills. Thickness was measured using an FEI QUANTA 400 FEG (Field Electron and Ion Company, FEI, Hillboro, OR, USA) scanning electron microscope, provided with an EDAX Genesys Energy Dispersive X-ray Spectroscopy microanalysis system (Edax Ametak, Mahwah, NJ, USA). The mounted samples were analyzed in different areas of the cutting area, the coating thickness was measured, and its average value was determined. The same range of magnifications was used for all images obtained from the SEM analyses, allowing a better comparison between samples. EDS analyses were also carried out to assess the coating's chemical composition (this analysis does not provide fully accurate values; however, its accuracy is sufficient to be used to ascertain the chemical composition of these coatings, avoiding the use of more expensive and time-consuming technologies). EDS analyses were performed using a beam potential of 15 kV, which was sporadically reduced to 10 kV, to decrease the interaction volume, thus reducing the noise in the obtained spectra.
