Figure 3 explains the morphology and distribution in each of the three
constituent powders. The granulometry difference is highlighted in the
images, as well as the distribution of nanometric particles around the
micrometric agglomerations that occurs in the mixture of NM powders.
Figure 3 also shows EDS analysis representative to the NM composition.
Beyond those expected elements constituents of the powder, Zr and Al are
detected in the HEM processed powders, but in higher content for the
Nano powder. The contamination comes from the Zr grinding bodies and the
alumina addition during the HEM process. It is a limiting factor of the
HEM process with respect to the degree of purity of the coatings.