Temperature effect on structural, mechanical properties and corrosion behaviour of CrN thin films deposited by magnetron sputtering

Abstract

Chromium nitride (CrN) thin films have been synthesised on Si(100) and stainless steel (SS304) substrates by direct current (DC) magnetron sputtering at different temperatures (25–100–200°C). The effects of temperature on structural and mechanical properties of the prepared films have been investigated. The CrN thin films have been described by X-ray diffraction to reveal their crystalline quality and texture. Results indicate that the grain size decreases with the temperature. The thickness of CrN films have been determined by scanning electron microscopy and their stoichiometry was measured by energy dispersive X-ray spectroscopy. Atomic force microscopy was employed to characterise the morphology of the surface for thin films and to calculate the roughness value. The results show that the hardness of films depends strongly on the grain size of the film. The micro-hardness of these films decreased with the increase in temperature. The corrosion of the CrN coating deposited was studied with corrosion potential, polarisation resistance, as well as electrochemical impedance spectroscopy techniques.