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Coatings in the Ta-Zr-Si-B-C-N system were produced by magnetron sputtering of a TaSi2-Ta3B4-(Ta,Zr)B2 ceramic target in the Ar medium and Ar-N2 and Ar-C2H4 gas mixtures. The structure and composition of coatings were studied using scanning electron microscopy, glow discharge optical emission spectroscopy, energy-dispersion spectroscopy, and X-ray diffraction. Mechanical and tribological properties of coatings were determined using nanoindentation and pin-on-disk tests using 100Cr6 and Al2O3 balls. The oxidation resistance of coatings was evaluated by microscopy and X-ray diffraction after annealing in air at temperatures up to 1200 °C. The reactively-deposited coatings containing from 30% to 40% nitrogen or carbon have the highest hardness up to 29 GPa and elastic recovery up to 78%. Additionally, coatings with a high carbon content demonstrated a low coefficient of friction of 0.2 and no visible signs of wear when tested against 100Cr6 ball. All coatings except for the non-reactive ones can resist oxidation up to a temperature of 1200 °C thanks to the formation of a protective film based on Ta2O5 and SiO2 on their surface. Coatings deposited in Ar-N2 and Ar-C2H4 demonstrated superior resistance to thermal cycling in conditions 20-T−20 °C (where T = 200–1000 °C). The present article compares the structure and properties of reactive and “standard-inert atmosphere” deposited coatings to develop recommendations for optimizing the composition.

Coatings were deposited by pulsed cathodic arc evaporation (PCAE) of a TiC–NiCr–Eu2O3 cathode fabricated by the powder metallurgy method. The deposition was carried out in different gas media, including Ar, N2, and C2H4. The structure, elemental, and phase compositions of coatings were studied by scanning electron microscopy (SEM), X-ray diffraction (XRD), energy-dispersive spectroscopy (EDS), Raman spectroscopy, and glow discharge optical emission spectroscopy (GDOES). Coatings were tested in terms of their hardness, elastic modulus, elastic recovery, friction coefficient, and wear and corrosion resistance. The obtained results demonstrated that the coatings deposited in Ar possessed higher hardness up to 20 GPa and an elastic recovery of 92%. Coatings produced using С2H4 showed the minimum friction coefficient (0.35 ± 0.01). The use of nitrogen as a gas medium led to the formation of coatings with the best corrosion resistance in sulfuric acid. Coatings formed in N2 had a free corrosion potential of +0.28 V and a corrosion current density of 0.012 µA/cm2.

Mo-Zr-Si-B coatings were deposited by high-power impulse magnetron sputtering at a pulse frequency of 10, 50, and 200 Hz. The coating structure was studied by scanning electron microscopy, energy-dispersive spectroscopy, glow-discharge optical-emission spectroscopy, transmission electron microscopy, and X-ray diffraction. The mechanical characteristics, adhesive strength, coefficient of friction, wear resistance, resistance to cyclic-dynamic-impact loading, high-temperature oxidation resistance, and thermal stability of the coatings were determined. The coatings, obtained at 10 and 50 Hz, had an amorphous structure. Increasing the frequency to 200 Hz led to the formation of the h-MoSi2 phase. As the pulse frequency increased from 10 to 50 and 200 Hz, the deposition rate rose by 2.3 and 9.0 times, while hardness increased by 1.9 and 2.9 times, respectively. The Mo-Zr-Si-B coating deposited at 50 Hz was characterized by better wear resistance, resistance to cyclic-dynamic-impact loading, and oxidation resistance at 1500 °C. Thermal stability tests of the coating samples heated in the transmission electron microscope column showed that the coating deposited at 50 Hz remained amorphous in the temperature range of 20–1000 °C. Long-term annealing in a vacuum furnace at 1000 °C caused partial recrystallization and the formation of a nanocomposite structure, as well as an increased hardness from 15 to 37 GPa and an increased Young’s modulus from 250 to 380 GPa, compared to those of the as-deposited coatings.