Substrate temperature influence on W/WCNx bilayers grown by pulsed vacuum arc discharge

W/WCNx coatings were produced by using a repetitive pulsed vacuum arc discharge on stainless-steel 304 substrates, varying the substrate temperature from room temperature to 200 °C. Energy dispersive spectroscopy (EDS) was used for determining W, C and N concentrations dependence on the substrate temperature. A competition between C and N can be observed. Atomic force microscopy was employed for obtaining the thickness and grain size that present similar tendencies as a function of the temperature. X-ray diffraction characterization showed phases of W and α-WCN (hexagonal). Raman spectra for all substrate temperatures were obtained, presenting two peaks corresponding to D (disorder) and G (graphite) bands in the region of 1100-1700 cm−1 due to the amorphous carbon. As an important conclusion, it was stated that substrate temperature has strong influence on the structure, chemical composition and morphology of W/WCNx bilayers, caused by the competition between carbon and nitrogen.

► WCN coatings present C and N concentration competition depending on the process production parameters as the substrate temperature. ► WCN coatings studied by means of Raman spectroscopy showed D and G bands corresponding to an amorphous component. ► The increase in the carbon inclusion in the WCN lattice produces an increment in the amorphous component.