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Chromium nitride and oxynitride coatings were deposited as monolayers ((Cr-N), Cr(N,O)) and bilayers (Cr-N/Cr(N,O), Cr(N,O)/Cr-N) on 304 steel substrates by reactive cathodic arc method. The coatings were characterised by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray spectrometry (EDS), surface profilometry, and scratch tester. The anticorrosive properties of the coatings were assessed by electrochemical tests in 0.10 M NaCl + 1.96 M H 2 O 2 , carried out at 24 • C. Cr 2 N, CrN, and Cr(N,O) phases were identified in the coatings by grazing incidence X-ray diffraction (GI-XRD) measurements. The measured adhesion values ranged from 19 N to 35 N, the highest value being obtained for the bilayer with Cr(N,O) on top. Electrochemical tests showed that Cr(N,O) presence in both mono-and bilayered coatings determined the lowest damage in corrosive solution, as compared to the Cr-N coatings. This improvement was ascribed to the more compact structure, lower coatings porosity, and smoother surface.

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