Magnetron deposition of metal-ceramic protective coatings on glasses of windows of space vehicles

Transparent refractory metal-ceramic nanocomposite coatings with a high coefficient of elasticrecovery and microhardness on the basis of Ni/Si-Al-N are formed on a glass substrate by the pulse magnetron deposition method. The structure-phase states were investigated by TEM, SEM. It was established that the first layer consists of Ni nanograins with a fcc crystalline lattice, the second layer is two-phase: 5-10 nm nanocrystallites of the AlN phase with the hcp crystalline lattice in amorphous matrix of the Si3N4 phase

Magnetron deposition of metal-ceramic protective coatings on glasses of windows of space vehicles

Transparent refractory metal-ceramic nanocomposite coatings with a high coefficient of elasticrecovery and microhardness on the basis of Ni/Si-Al-N are formed on a glass substrate by the pulse magnetron deposition method. The structure-phase states were investigated by TEM, SEM. It was established that the first layer consists of Ni nanograins with a fcc crystalline lattice, the second layer is two-phase: 5-10 nm nanocrystallites of the AlN phase with the hcp crystalline lattice in amorphous matrix of the Si3N4 phase

Thermal stability of Ba1-xCaxF2 solid solutions

Ba1-xCaxF2 samples with fluorite-type structure were prepared by high-energy ball milling. DSC measurements revealed exothermic decomposition at temperatures of about 450 °C. Decomposition was also observed by high temperature X-ray experiments. As a product, two phases with compositions close to pure BaF2 and CaF2 were obtained. The decomposition temperature observed by X-ray measurements is lower than in the DSC experiments. This might indicate that X-ray irradiation could foster the decomposition

Diamond seed dependent luminescence properties of CVD diamond composite

Diamond-based X-ray luminescent composites are robust materials to be used in synchrotrons and free-electron lasers to detect and visualize high-intensity X-ray beams. Such composites consist of luminescent rare-earth (RE) particles embedded into an X-ray transparent diamond matrix. In this work, polycrystalline diamond composites with embedded particles of EuF3, SrF2:Eu and YAG:Ce were grown by microwave plasma CVD using diamond seeds with an average particle size difference of two orders of magnitude: from 5 nm up to 500 nm, with positive and negative zeta potentials. The structure, phase composition, and luminescent characteristics of the resulting composite films were investigated and analyzed. We found that various particle types can be better-suited for different composites, and the exact seeding should be selected on the case-by-case basis. The direct comparison of various diamond-based composites, grown in the identical CVD conditions but with various luminescent powders, show that YAG:Ce particles in diamond allow achieving a brighter photoluminescence (PL) in comparison to Eu-based fluorides. However, the set of fluoride powders doped with Eu3+ ions allow obtaining unusually narrow (FWHM = 0.9 nm) and intensive line near 611 nm in PL spectra, which might be better-suited for detection and characterization applications rather than a broad peak of Ce with FWHM ≈ 120 nm