from the conferences organized by TANGER Ltd.
The ZrB2–MoSi2 coating modified by Y2O3 and Al was prepared on a carbon/carbon composite substrate by a new multi-chamber detonation accelerator (MCDS). The thickness of deposited coatings ranged about 90-130 μm. The powder containing 41 mol.% of ZrB2, 5 mol.% of MoSi2, 1 mol.% of Y2O3 and 53 mol.% of Al (1-25 μm) has been used as the feedstock material to deposit a dense layer. The structural-phase state of the coatings was characterized by X-ray diffraction and scanning electron microscopy with energy-dispersive spectroscopy. The ZrB2–MoSi2 coating was well-adhered with carbon/carbon composites. The coating displayed compact microstructure with porosity lower than 1%. It was established that phase composition of ZrB2–MoSi2 powder under the influence of high temperatures and the atmosphere of detonation products changes with the formation of a complex heterogeneous structural-phase state in the coatings. As-sprayed coating consisted of t-AlZrO2, fcc-Al, m-ZrO2 and m-SiO2. ZrB2–MoSi2 coatings are characterized by the presence of nanodispersed particles. The most of the powder particles were melted and formed lamellar-like structure typical for thermally sprayed coatings. But small amount of partially-melted areas has non-uniform structure, ranging from lamella to sphere with a size range of 0.05-1.5 μm.
Keywords: Multi-chamber detonation accelerator, ZrB2–MoSi2 coatings, carbon/carbon composites, microstructure© This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.