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[References: 56 tit.]

Nickel-chromium coatings were deposited on Zr1Nb alloy using magnetron sputtering systems with «hot» Ni and cooled Cr targets. The effect of coating composition on high-temperature oxidation resistance and hydrogen uptake of Zr1Nb was studied. Hydrogen uptake of the alloy was measured in situ under gas-phase hydrogenation at 633?K. High-temperature oxidation was performed in air atmosphere at 1173–1373?K for 20?min. It was shown that the coating with high Ni content (83?at.%) drastically increases hydrogen uptake of the Zr1Nb alloy and demonstrates low oxidation resistance even at 1173?K. The coatings with Cr content =45?at.% have low hydrogen permeability which reduces the rate of hydrogen uptake of the alloy. The oxidation resistance of the NiCr coatings increases with Cr content in the as-deposited coatings. The pure Cr coating exhibits the best oxidation resistance: only 8?µm-thick oxide layer was observed. There is also found the intensive diffusion of nickel into the alloy during high-temperature oxidation of the samples coated by NiCr films with 55 and 17?at.% Ni. The as-deposited NiCr coatings are less brittle than the pure Cr coating, but their mechanical properties degrade stronger than for the Cr coating after the oxidation test.