The structure of MB2MCC (MZr, Hf, Ta) multi-phase ceramic coatings on graphite

A new class of MB2MCC multi-phase ceramic coatings were fabricated via pilling up MB2 (MZr, Hf, Ta) powders on the surface of graphite plates followed by heating at 2823 K. Results showed that with the increase of atomic number of Zr, Hf, and Ta, the wettability of the ceramics on graphite plates increased. The surface and inside morphology of the ceramic coatings were different from each other. The graphite inside these ceramic coatings was highly ordered with graphite interlayer distance closing to that of single crystal graphite (0.3354 nm) and some B of MB2 diffused into graphite causing the decrease of local symmetry without disrupting the graphite structure. This approach is envisaged as a promising path to develop new kinds of ultra-high temperature material coatings for carbon materials.